Prepared in cooperation with the U.S. Fish and Wildlife Service

The History of Patuxent: America’s Wildlife Research Story

Circular 1422

U.S. Department of the Interior

U.S. Geological Survey
Cover. Clockwise from top, left: Dedication of Patuxent Research Refuge at Snowden Hall, Laurel, MD, June 1939 (Photo by Bureau of 

Biological Survey); Dr. Lucille Stickel, U.S. Fish and Wildlife Service, an important research scientist in 1940s to 1960s and Director of Patuxent 

Wildlife Research Center in 1970s to 1980s (Photo by U.S. Fish and Wildlife Service); banded young ospreys on nest in Chesapeake Bay, 

2012 (Photo by Rebecca S. Lazarus, U.S. Geological Survey); Chuck Henny, U.S. Fish and Wildlife Service, holding a red-tailed hawk prior to 

banding, Patuxent Research Refuge, spring 1972 (Photo by Matthew C. Perry, U.S. Fish and Wildlife Service); Barnett Rattner, U.S. Geological 

Survey (left), and Pete McGowan, U.S. Fish and Wildlife Service, Chesapeake Bay, 2013 (Photo by Reese F. Lukei, Jr., Center for Conservation 

Biology, College of William and Mary, Williamsburg, VA); whooping crane named Canus at Patuxent Wildlife Research Center, 1991 (Photo 

by Matthew C. Perry, U.S. Fish and Wildlife Service); Alicia Berlin, U.S. Geological Survey, weighing common eider in seaduck colony for 

selenium study at Patuxent Wildlife Research Center, 2004 (Photo by Matthew C. Perry, U.S. Geological Survey); wolf with collar-mounted 

transmitter being tracked by David Mech, U.S. Fish and Wildlife Service, in Minnesota (Photo by U.S. Fish and Wildlife Service). Center: 

Chan Robbins, U.S. Fish and Wildlife Service, recording data on birds in trap at Patuxent Research Refuge, late 1940s (Photo by U.S. Fish and 

Wildlife Service).
The History of Patuxent:

America’s Wildlife Research Story

Edited by Matthew C. Perry

Prepared in cooperation with the U.S. Fish and Wildlife Service

Circular 1422

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

SALLY JEWELL, Secretary

U.S. Geological Survey

Suzette M. Kimball, Director

U.S. Geological Survey, Reston, Virginia: 2016

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visit http://store.usgs.gov/.

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the 

U.S. Government.

Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials 

as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.

Suggested citation:

Perry, M.C., ed., 2016, The history of Patuxent—America’s wildlife research story: U.S. Geological Survey 

Circular 1422, 255 p., https://doi.org/10.3133/cir1422.

Library of Congress Cataloging-in-Publication Data

Names: Perry, Matthew Calbraith, editor. | U.S. Fish and Wildlife Service. |

 Geological Survey (U.S.), issuing body.

Title: The History of Patuxent : America’s wildlife research story / edited

 by Matthew C. Perry ; prepared in cooperation with the U.S. Fish and

 Wildlife Service.

Other titles: U.S. Geological Survey circular ; 1422. 1067-084X

Description: Reston, Virginia : U.S. Geological Survey, 2016. | Series:

 Circular, ISSN 1067-084X ; 1422 | Includes bibliographical references.

Identifiers: LCCN 2016055774| ISBN 9781411340992 (paperback) | ISBN

 141134099X (paperback)

Subjects: LCSH: Patuxent Wildlife Research Center--History. | Patuxent

 Research Refuge (U.S.)--History.

Classification: LCC QL84.22.M3 H57 2016 | DDC 333.95/4097524--dc23 | SUDOC I

 19.4/2:1422

LC record available at https://lccn.loc.gov/2016055774

ISSN 1067-084X (print)

ISSN 2330-5703 (online)

ISBN 978-1-4113-4099-2
iii

Foreword

The facility known as Patuxent has evolved from the original Patuxent Research Refuge to 

the Patuxent Wildlife Research Center, and eventually to a two-agency facility with two clear, 

though distinct, missions. President Franklin D. Roosevelt established Patuxent as the Nation’s 

first wildlife research station through an Executive Order in 1936. Originally, the research and 

wildlife conservation missions were conjoined; these missions continue today, but under two 

different agencies in a collaborative partnership. The U.S. Geological Survey (USGS) administers 

Patuxent Wildlife Research Center and the U.S. Fish and Wildlife Service (USFWS) administers 

Patuxent Research Refuge. Together, they are “Patuxent.”

Great conservation icons such as Mr. J.N. “Ding” Darling and Dr. Ira N. Gabrielson were 

instrumental in establishing Patuxent and investing in America’s great conservation future, 

even as the country was in the midst of the Great Depression. Through the years, the staff of 

Patuxent has been at the forefront of scientific achievement in the study of migratory birds, 

environmental contaminants, and endangered species. Innovations of Patuxent scientists have 

pushed the limits of techniques for field investigations, including the use of satellite telemetry, 

that have facilitated successful biological investigations throughout the world. Changes in 

research methods through the years have been prodigious, inasmuch as some naturalists 

early in Patuxent’s history believed that banding and color-marking of birds were too invasive. 

Since then, USGS and USFWS staff at Patuxent have spearheaded the development and 

successful application of adaptive strategies and structured decision-making tools to realworld conservation and management issues. Patuxent’s vision and mission define its purpose 

and direction. Working with a wide variety of partners is Patuxent’s approach to ensuring that 

relevant, high-quality, objective science continues to support society’s needs while maintaining 

its role as an active and productive Federal research institution.

Patuxent evolved from its origin in the U.S. Biological Survey to become the only research refuge 

of the USFWS, and then to assume its current position as one of 17 Biological Research Centers 

of the USGS, which is the natural resources research arm of the Department of the Interior. 

The USFWS, through the National Wildlife Refuge System, administers the Patuxent Research 

Refuge, and the two agencies remain focused on their primary mission of research and wildlife 

conservation. We invite you to explore Patuxent’s history and the information presented in the 

pages that follow.

John B. French Bradley A. Knudsen

Director, Patuxent Wildlife Research Center Manager, Patuxent Research Refuge
iv

Preface

This report, based on a symposium held on 

October 13, 2011, at the National Wildlife 

Visitor Center at the Patuxent Research 

Refuge in Laurel, MD, documents the 

history of the Patuxent Research Refuge 

and the Patuxent Wildlife Research 

Center, collectively known as Patuxent. 

The symposium was one of the many 

activities occurring at that time to 

celebrate the 75th anniversary of the 

creation of the Patuxent Research Refuge 

in 1936. The Patuxent Wildlife Research 

Center is located at the refuge, and the 

research center director, Dr. Gregory J. 

Smith, with great enthusiasm, personally 

supervised all aspects of the celebration. 

The symposium was coordinated by Dr. 

Matthew C. Perry, the editor of this report, 

with Dr. Smith’s strong support. The refuge and the research center have been essentially 

synonymous for the almost 80 years of their history.

Dr. Smith’s strong interest in Patuxent history and the symposium were major factors in the 

overwhelming success of the 75th anniversary celebration, in which he played a major role. 

Symposium attendees included a large number of dignitaries as well as virtually the entire staffs 

of the Patuxent Wildlife Research Center and the Patuxent Research Refuge.

Unfortunately, Dr. Gregory James Smith passed away at the age of 58 on April 11, 2014, while 

on official business in Beijing, China, where he was contributing to ongoing discussions on avian 

influenza and global climate change. Because of the importance of his contributions to wildlife 

science in general and Patuxent in particular, and because of his dedication to the publication of 

this report, a brief description of his life and career is included below.

Greg enrolled in Northern Michigan University and received his bachelor’s degree in biology in 

1978. He went on to earn a master’s degree in wildlife ecology and a Ph.D. in wildlife ecology 

and veterinary science from the University of Wisconsin—Madison in 1984. Greg’s passion for 

the environment directed his entire career path.

Having more than 35 years of ecological research and management experience, Greg 

spearheaded many environmental initiatives. His career began with post-doctoral studies at 

the Patuxent Wildlife Research Center and came full circle when he became the director of 

the research center in 2009. During his career, he also was appointed director of the National 

Wetlands Research Center in Lafayette, LA, in 2004, and the Great Lakes Science Center in Ann 

Arbor, MI, in 1996, making him the first and only person to direct three different U.S. Geological 

Survey wildlife research centers.

Photo by Kinard Boone, U.S. Geological Survey.
v

Greg felt privileged to work in partnership with scientists and friends in Russia and Southeast 

Asia. He was particularly proud of projects on the Mekong River and his relationships with the 

many partners who live and work there. He was honored to serve on the board of the National 

Wildlife Federation and devoted time and energy to the mission of that organization.

In his first year as director of the National Wetlands Research Center, the Gulf Coast and 

particularly New Orleans were ravaged by two hurricanes, Katrina and Rita. Greg rushed into 

action, using the Center’s boats as life-saving vessels for New Orleans victims, and personally 

rescuing families in dire trouble during the aftermath. For these efforts, his team was awarded 

the Service to America Medal by the nonpartisan Partnership for Public Service, to honor 

excellence in Federal civil service.

Greg had not only a passion for his work, but also a passion for life. He loved the sea and was 

an avid sailor, building boats and chartering trips around the Caribbean during his college days. 

Greg continued to pursue this interest throughout his life, racing sailboats in Chesapeake Bay 

and around the world. He shared his love of the sea with his family, marrying Kathy, his wife, on 

their boat and spending weekends with their two children on the water.

He traveled to more than 65 countries, making friends and finding adventure with every step—

from hiking through the Tibetan Himalayas, to diving the oceans, to trekking through jungles and 

savannahs. The lives he touched span the world.

Greg loved Patuxent and took pride in its long and distinguished history. He was director during 

the 75th anniversary and supported all of the celebratory activities with great excitement. He 

was especially supportive of this project—to publish a report based on the proceedings of the 

symposium held at Patuxent during the anniversary celebration. The Patuxent community misses 

him greatly; we acknowledge his contributions to wildlife science and honor his memory by 

fulfilling his wish to publish this report about the history of Patuxent.
vi

Acknowledgments

The authors gratefully acknowledge Shannon Beliew of the U.S. Geological Survey (USGS) 

Patuxent Wildlife Research Center (Patuxent) for logistical assistance; Lynda J. Garrett, USGS 

Patuxent librarian (retired), for invaluable assistance with literature searches and editing; and

Dale L. Simmons, USGS, for outstanding editing.
vii

Contents

Foreword ...............................................................................................................................................iii

Preface ..................................................................................................................................................iv

Acknowledgments...............................................................................................................................vi

Topic 1: The Early Years of Patuxent Research

Patuxent’s Development: The People and the Projects

By Matthew C. Perry ................................................................................................................. 1

Early Avian Studies at Patuxent

Chandler S. Robbins ................................................................................................................ 13

Early Population And Contaminant Studies At Patuxent

By Russell J. Hall...................................................................................................................... 25

Topic 2: Migratory Bird Research, Monitoring, and Management

Migratory Bird Program at the U.S. Geological Survey Patuxent Wildlife Research Center/

U.S. Fish and Wildlife Service Patuxent Research Refuge: Transformations in 

Management and Research

By R. Michael Erwin and Robert J. Blohm........................................................................... 29

The Bird Banding Laboratory: Support for and Collaboration with Research at Patuxent

By John Tautin.......................................................................................................................... 45

Patuxent’s Role in the Development of the North American Breeding Bird Survey

John R. Sauer........................................................................................................................... 53

The Migratory Bird and Habitat Research Laboratory and the Accelerated Research 

Program

By Richard A. Coon.................................................................................................................. 65

Patuxent’s American Black Duck Studies from Chesapeake Bay to Maine and Beyond

By Jerry R. Longcore............................................................................................................... 69

Topic 3: Environmental Contaminant Research Program 

Lucille and Bill Stickel: A Personal Perspective

By Nancy C. Coon .................................................................................................................... 87

Lead Poisoning Studies and Shooting Tests with Soft-Iron Shot

By Jerry R. Longcore and Ralph Andrews .......................................................................... 91

Patuxent Researchers Tackle Heavy Metal Poisoning in Wildlife

By Gary H. Heinz..................................................................................................................... 101

Role of Raptors in Contaminant Research at Patuxent

By Charles J. Henny .............................................................................................................. 107

Research on Amphibians and Reptiles at Patuxent: A Synopsis

By Donald W. Sparling .......................................................................................................... 121

Chesapeake Bay Contaminant Studies by Patuxent Wildlife Research Center Scientists

By Barnett A. Rattner............................................................................................................ 127
viii

Topic 4: Endangered Species Research Program

Overview of the Endangered Species Program

Glen Smart............................................................................................................................... 141

Conserving California Condors in the 1980s

Noel F.R. Snyder..................................................................................................................... 147

Endangered Species Research in the Caribbean

James W. Wiley ..................................................................................................................... 157

A Personal Perspective on Searching for the Ivory-Billed Woodpecker: A 41-Year Quest

Paul W. Sykes, Jr.................................................................................................................... 171

Endangered Species Research in Hawaii: The Early Years (1965–87)

J. Michael Scott and Cameron B. Kepler .......................................................................... 183

Patuxent’s Long-Term Research on Wolves

L. David Mech......................................................................................................................... 197

Topic 5: Other Programs at Patuxent

Wildlife Disease Studies at Patuxent

Glenn H. Olsen........................................................................................................................ 213

Urban Wildlife Research at Patuxent

Lowell W. Adams ................................................................................................................... 221

Patuxent Research Refuge—Supporting Wildlife Science

Bradley A. Knudsen............................................................................................................... 231

History of the Library at Patuxent Wildlife Research Center

By Lynda J. Garrett................................................................................................................ 235

Patuxent’s Research Program in an Era of Transitions

James A. Kushlan .................................................................................................................. 239

Facility and Research Initiatives at Patuxent for the New Millennium

Judd A. Howell ....................................................................................................................... 249

Appendix 1. Contributors and Contact Information, September 2016......................................253
ix

Conversion Factors

[Inch/Pound to International System of Units]

Multiply By To obtain

Length

inch (in.) 2.54 centimeter (cm)

inch (in.) 25.4 millimeter (mm)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

Area

acre 4,047 square meter (m2

)

acre 0.4047 hectare (ha)

acre 0.004047 square kilometer (km2

)

square foot (ft2

) 0.09290 square meter (m2)

square mile (mi2

) 259.0 hectare (ha)

square mile (mi2

) 2.590 square kilometer (km2) 

Volume

gallon (gal) 3.785 liter (L) 

cubic foot (ft3) 0.02832 cubic meter (m3) 

Mass

ounce, avoirdupois (oz) 28.35 gram (g) 

pound, avoirdupois (lb) 0.4536 kilogram (kg) 

Application rate

pounds per acre per year 

[(lb/acre)/yr]

1.121 kilograms per hectare per year

[(kg/ha)/yr]

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as:

°F = (1.8 × °C) + 32.

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as:

°C = (°F – 32) / 1.8.

Datum

Vertical coordinate information is referenced to the North American Vertical Datum of 1988 

(NAVD 88).

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).

Altitude, as used in this report, refers to distance above the vertical datum.
x

Abbreviations

< less than

> greater than

AHM Adaptive Harvest Management

ALAD aminolevulinic acid dehydratase

AOU American Ornithologists’ Union

ARM Adaptive Resource Management

ARMI USGS Amphibian Research and Monitoring Initiative

ARP Accelerated Research Program

BARC Beltsville Agricultural Research Center

BBL Bird Banding Laboratory

BBS Breeding Bird Survey

BDJV Black Duck Joint Venture

BHC benzene hexachloride

BLM Bureau of Land Management

BRD Biological Resources Discipline

BSFW Bureau of Sport Fisheries and Wildlife

CBC Christmas Bird Count

CCC Civilian Conservation Corps

CCS Call-Count Survey

ChE cholinesterase

CPV canine parvovirus

CSA Cambridge Scientific Abstracts

DDD dichlorodiphenyldichloroethane

DDE dichlorodiphenyldichloroethylene

DDT dichlorodiphenyltrichloroethane

DEW Distant Early Warning

DLNR Department of Land and Natural Resources

DMBM Division of Migratory Bird Management

DNA deoxyribonucleic acid 

DNR Department of Natural Resources

DOI Department of the Interior

EDTA ethylenediaminetetraacetic acid

FEPCA Federal Environmental Pesticides Control Act
xi

FY fiscal year

GAP Gap Analysis Program

GPS global positioning system

GS General Schedule

HAB harmful algal bloom

HCP habitat conservation plan

HDFW Hawaii Department of Forestry and Wildlife

HFBS Hawaiian Forest Bird Survey

HIP Harvest Information Program

IAFWA International Association of Fish and Wildlife Agencies

IBCC International Bird Census Committee

IBWO ivory-billed woodpecker

IIT-RI Illinois Institute of Technology-Research Institute

IITF International Institute of Tropical Forestry

ILL interlibrary loan

IPDS Information Product Data System

IRM Information Resources Management

IWBO ivory-billed woodpecker

LSU Louisiana State University

MBHRL Migratory Bird and Habitat Research Laboratory

MBMO Office of Migratory Bird Management (now, DMBM)

MBPS Migratory Bird Population Station

MCP minimum convex polygon

min minute

MN Minnesota

MOA memorandum of agreement

MOS Maryland Ornithological Society

MWI Mid-winter inventory

NAAMP Patuxent North American Amphibian Monitoring Program

NABCI North American Bird Conservation Initiative

NAWMP North American Waterfowl Management Plan

NBS National Biological Survey

NGO nongovernmental agency

NLCD National Land Cover Data

NPS National Park Service
xii

NRDA Natural Resource Damage Assessment

NWR National Wildlife Refuge

OC organochlorine

OCLC Online Computer Library Center, Inc.

OP organophosphate

PAH polynuclear aromatic hydrocarbon

PBDE polybrominated diphenyl ether

PC personal computer

PCB polychlorinated biphenyl

ppm parts per million

PRDNR Puerto Rico Department of Natural Resources

PRR Patuxent Research Refuge

PWRC Patuxent Wildlife Research Center

SAAMI Sporting Arms and Ammunition Manufacturers’ Institute

SDM Structured Decision-Making

SE standard error

SGS Singing-Ground Survey

SNF Superior National Forest

SOS Save Our Shearwaters

TQM total quality management

URL Universal Resource Locator

USDA U.S. Department of Agriculture

USFWS U.S. Fish and Wildlife Service

USGS U.S. Geological Survey

WBS Winter Bird Survey

WMA wildlife management area

ww wet weight
The Early Years of Patuxent Research

Patuxent’s Development: The People and the Projects

By Matthew C. Perry

Dedication of Patuxent Research Refuge at Snowden Hall, Laurel, MD, 

June 1939. Photo by Bureau of Biological Survey.

Early Wildlife Conservation Research

Although several conservation activities took place in 

the United States in the early 1900s, it was not until the 1930s 

that scientific wildlife management and the research to support 

it were initiated. The formation of Patuxent Research Refuge 

(Patuxent) was one of many wildlife conservation activities that occurred in the mid-1930s. On December 16, 1936, 

President Franklin D. Roosevelt signed Executive Order 7514, 

which transferred 2,670 acres of land that had been acquired 

(or would be acquired) by the United States to the Department 

of Agriculture (USDA) as a wildlife experiment and research 

refuge. The area delineated in the order was located in Anne 

Arundel and Prince George’s Counties, MD, and was created “to effectuate further the purposes of the Migratory Bird 

Conservation Act.” By order of the President, the area was to 

be known as “the Patuxent Research Refuge.”

The refuge was dedicated on June 3, 1939, at Snowden 

Hall by Secretary of Agriculture Henry A. Wallace, who stated 

that “the chief purpose of this refuge is to assist in the restoration of wildlife—one of our greatest natural resources.” 

Secretary Wallace recognized “the vision and foresight of Dr. 

Ira N. Gabrielson, Chief of the Biological Survey,” and “the 

leadership of Dr. Leland C. Morley, superintendent of the refuge.” He further stated that the Nation’s first wildlife research 

station was “the manifestation of a national determination 

and a national ability to conserve and administer wisely the 

organic resources and products of the soil—a priceless heritage to the generations of Americans yet to come.” Although 

Mr. Jay N. “Ding” Darling, former Chief of the Bureau of 

Biological Survey, was not present or mentioned in Secretary 

Wallace’s address, many people also credit the formation of 

the Patuxent Research Refuge to his interest and support.

Superintendent Dr. Leland C. Morley in front of Log Cabin—Patuxent Research 

Refuge’s first office building. Photo by Bureau of Biological Survey.
2 The History of Patuxent: America’s Wildlife Research Story

Snowden Hall at the Patuxent Research Refuge, Laurel, MD, about 1936. Photo by Bureau of Biological Survey.

Patuxent’s location adjacent to the Beltsville Agricultural 

Research Center at Beltsville, MD, made it an appropriate 

area, according to Wallace, upon which to conduct “long-time 

studies on the interrelationships of wildlife with agriculture 

and forestry.” Secretary Wallace and Dr. Gabrielson envisioned an area where wildlife could be studied in relation to 

the production of agricultural crops, and where lands poorly 

suited for agriculture could be turned back into forests, fields, 

and meadows, thus again becoming productive for wildlife.

An interesting change in the relation between humans 

and wildlife, however, had taken place during the 1930s. 

Previously, wildlife investigations in the USDA had focused 

on the impact of wildlife on activities of humans; however, the 

long drought of the 1930s coupled with decades of wetland 

drainage by humans devastated North America’s waterfowl 

populations. Consequently, Americans were becoming more 

aware of the negative effects of their activities on wildlife. It 

was appropriate, therefore, that in 1939 the Bureau of Biological Survey was transferred from the USDA to the Department 

of the Interior (DOI). By 1940, the Bureau of Biological Survey was replaced by the Fish and Wildlife Service. It was not 

until 1956 that Congress renamed this agency the U.S. Fish 

and Wildlife Service (USFWS).

Dr. Leland C. Morley was superintendent of the refuge during the embryonic years from 1938 to 1948. He was 

responsible for the construction and development of the 

facilities to be used for wildlife research (Morley, 1948). 

Under his administration, three major buildings (Merriam, 

Henshaw, and Nelson Laboratories), named for the first three 

chiefs of the Bureau of Biological Survey, were constructed 

in 1939-41 through the efforts of the Works Progress Administration and the Public Works Administration headquartered 

in Washington, D.C. Some of the early Patuxent biologists 

traveled between Patuxent and their homes in Washington in 

trucks used to transport construction workers. On-site quarters 

were constructed for some biologists in the early 1940s to 

allow researchers to remain near their work. The first wetland 

area, Cash Lake, was built by the Civilian Conservation Corps 

(CCC) and was flooded in 1939 as a recreational area for 

fishing. The CCC was also responsible for transplanting many 

trees from the woods to landscape the new buildings.

With the outbreak of World War II, many of the Patuxent 

men were called for military service. Older male staff members and some women continued the wildlife conservation 

work and, beginning in 1943, were assisted by the Civilian 

Public Service Program, which established at Patuxent a group 

of conscientious objectors to the war. These men were credited 

with constructing Snowden Pond and several roads, and conducting surveys of wildlife and plants.

Dr. Morley supervised construction at Patuxent during the 

late 1930s and early 1940s. Research, however, was directed 

by administrators in Washington through their assistants, who 

were working at Patuxent. Dr. Alexander C. Martin was in 

charge of food habits research, which was located in Merriam 

Laboratory. Wildlife disease research, headed initially by Dr. 

J.E. Shillinger and later by Dr. Donald Coburn, was located in 
The Early Years of Patuxent Research

Patuxent’s Development: The People and the Projects 3

Works Progress Administration workers at Patuxent Research Refuge, Laurel, MD. Photo by Bureau of Biological Survey.

Civilian Public Service Program members at Snowden Hall, Patuxent Research Refuge, Laurel, MD. Photo by Bureau of Biological Survey.
4 The History of Patuxent: America’s Wildlife Research Story

Henshaw Laboratory. All bird banding studies were administered in Nelson Laboratory and conducted at field locations 

throughout the country.

From 1942 to 1948, Mr. Arnold L. Nelson supervised 

all research at Patuxent from the Washington headquarters. 

In 1948, his office was moved to Patuxent, and he served as 

Patuxent’s first official director until his retirement in 1959. 

Dr. Gustav Swanson became Chief of Research at headquarters. Mr. Nelson’s responsibilities included both land 

management and research. The farm game research, which 

compared the diversity and numbers of wildlife under various farming practices, began under Mr. Nelson. Dr. Durward 

Allen headed this program, which compared two major farm 

practices, one that provided good wildlife habitat and one 

that did not (Warbach, 1958). The program was terminated 

before it reached its full potential for production of data, but 

many findings were published in popular outlets and used 

by farmers and refuges throughout the country. Dr. Allen 

authored “The Farmer and Wildlife,” which was published 

by the Wildlife Management Institute and had seven printings (Allen, 1949). Dr. Allen also published “Our Wildlife 

Legacy,” which includes much of the findings about optimum 

wildlife management techniques that were developed at 

Patuxent (Allen, 1954).

Long-term studies of certain single species forest 

wildlife, including box turtles (Terrapene carolina), black 

rat snakes (Elaphe obsoleta), and red-shouldered hawks 

(Buteo lineatus), also were initiated in the 1940s to 1950s. 

These species were optimum for long-term studies as they are 

common at Patuxent and can be captured and marked relatively easily. The box turtle studies initially were overseen by 

Dr. Lucille Stickel, but were later led by Dr. Russell Hall and 

then Dr. Paula Henry. Mr. William Stickel headed the black 

snake studies, which sometimes sent most of the staff searching for snakes. Mr. Elwood Martin and Dr. Charles Henny 

continued the red-shouldered hawk studies begun by Mr. 

Frederick Schmid. These programs represent some of the longest studies conducted on single species of wildlife. Extensive 

surveys were also conducted on all bird species at Patuxent 

during different seasons (Stewart and others, 1952).

Mr. Nelson was instrumental in continuing the development of the refuge for wildlife, while promoting research 

that would document habitat management techniques most 

beneficial for wildlife. Patuxent’s first field station was established in Alabama to evaluate the interrelations between quail 

populations and habitat manipulations. Most of the waterfowl 

impoundments that exist today at Patuxent were developed 

during Mr. Nelson’s tenure, and studies were begun to determine how best to manage those areas for wildlife. Techniques 

developed at Patuxent to help farm game and wetland species 

were widely adopted throughout the country.

In 1956, the Patuxent Research Refuge was renamed 

the Patuxent Wildlife Research Center to standardize the 

name with the adjacent Agricultural Research Center and 

with another USFWS facility in Denver, CO. The name 

change was done by administrative memorandum and did 

not supersede the original Executive Order designation as a 

Research Refuge.

Dr. Gustav Swanson (left), Research Chief, U.S. Fish and Wildlife Service, and Mr. Arnold Nelson, Director of Patuxent Research 

Refuge (PRR), at Cash Lake, PRR, Laurel, MD, on January 8, 1954. Photo by Francis M. Uhler, Patuxent Research Refuge.
The Early Years of Patuxent Research

Patuxent’s Development: The People and the Projects 5

The Environmental Movement and 

New Research

Dr. John L. Buckley became the director of Patuxent in 

1959 and served until 1963. Under his leadership the pesticide research program, begun in the 1940s, was broadened to 

include other chemicals and became known as the Environmental Contaminants Research Program. An increased emphasis on experimental design and statistically controlled studies 

developed during this period. There was an increasing belief 

at Patuxent that field studies should receive less emphasis 

because of the difficulties inherent in controlling environmental and habitat variables that are not encountered in standardized pen studies. Observations in the field could now be tested 

under “laboratory” conditions.

Secretary of the Interior Stewart Udall dedicated a new 

building for the Environmental Contaminants Research 

Program in 1963. The building was originally named the 

Biochemistry and Wildlife Pathology Laboratory. Throughout 

his dedication speech, Secretary Udall referred to the work 

of Rachel Carson and her famous book, “Silent Spring,” 

published in 1962. Ms. Carson never worked at Patuxent, but 

based some of her book on research done there. Interestingly, 

Ms. Carson never mentions Patuxent by name in her book, but 

refers to it as a laboratory near Laurel, MD. In 1989, the building was renamed Stickel Laboratory for Dr. Lucille and Mr. 

William Stickel, who had devoted a combined total of 78 years 

to research at Patuxent.

The bird control research program, which had been initiated by Mr. Nelson, was expanded during Dr. Buckley’s tenure 

to become the Section of Animal Control Studies. The Wetland 

Ecology Section of Patuxent conducted waterfowl habitat 

management research, with major activities addressing waterlevel manipulation and artificial nesting structures taking place 

on the Patuxent grounds. Extensive studies of lead poisoning 

in waterfowl caused by the ingestion of spent lead-shot pellets 

began at this time and continued through the 1960s. In 1961, 

other migratory bird research and management programs, 

including the Bird Banding Laboratory, were consolidated 

in a newly established Migratory Bird Populations Station at 

Patuxent, headed by Mr. Walter F. Crissey (Crissey, 2006).

Dr. Eugene H. Dustman served as Patuxent’s director 

from 1963 to 1972. During his tenure, Coburn Laboratory, 

the Service Building, and Gabrielson Laboratory were constructed. Gabrielson Laboratory was dedicated in 1969 in a 

well-attended celebration, and Dr. Gabrielson gave a speech. 

In 1969, Prince Charles of Great Britain and Mr. David Eisenhower, grandson of President Eisenhower, visited Patuxent 

and were given a tour led by Dr. Dustman and Dr. Stickel.

Prince Charles and David Eisenhower visit Patuxent Wildlife Research Center, 

Laurel, MD, 1969. Photo by U.S. Fish and Wildlife Service.

Dedication of Gabrielson Laboratory, Patuxent Wildlife Research Center, Laurel, MD, 1969. Photo by U.S. Fish and Wildlife Service.
6 The History of Patuxent: America’s Wildlife Research Story

Endangered Species Research

The Endangered Species Research Program began in 

1965, headed by Dr. Ray C. Erickson, who also served as the 

first associate director of Patuxent. Although the first bald 

eagle arrived at Patuxent in 1961 as part of the contaminant 

program studies, the first bald eagle and whooping crane used 

in the endangered species program arrived at Patuxent in 1965 

and 1966, respectively. This was the genesis of the captive 

propagation program that attained international prominence. 

The whooping crane was named Canus for Canada and United 

States, and reflected the close and long-lasting cooperation 

between the two countries with this species, which has continued since throughout the propagation program.

An additional 750 acres of land were purchased from the 

Shaefer family in 1970 as a buffer for the endangered species 

area, and several small support buildings, including a veterinary hospital, were constructed. A major endangered species 

laboratory was planned, but was never funded.

Innovative wetland management research was conducted 

during Dr. Dustman’s era on approximately 300 acres of water 

impoundments that had been created at Patuxent. Improved 

nest boxes were designed for wood ducks, mallards, and black 

ducks, which greatly aided the nesting success of these species. Drawdown techniques for impoundments were perfected 

to optimize moist-soil management for waterfowl (Perry and 

others, 2000). A manual on wood duck habitat needs was 

disseminated and used extensively by managers across the 

country. These techniques were then employed in many states 

throughout the United States and in other countries. Mr. Frank 

McGilvrey published an article on starling deterrent nest boxes 

that could be used by wood ducks, but deterred nesting by the 

problematic starlings (McGilvrey and Uhler, 1971). Unfortunately, this optimum design was not widely accepted as a 

result of the ease of making wooden wood duck nest boxes 

originally designed by Mr. Frank Bellrose.

Patuxent’s Wetland Ecology Section and part of the 

Migratory Bird Populations Station were combined in 1972 

into a new group called the Migratory Bird and Habitat 

Research Laboratory (MBHRL) under the direction of Dr. 

Robert I. Smith and, later, Dr. Fant Martin. MBHRL personnel 

conducted extensive research on species of concern in specific 

geographic areas, including woodcock and black ducks in 

Maine, canvasbacks in Chesapeake Bay, and mourning doves 

in South Carolina.

Dr. Lucille F. Stickel became the director of Patuxent in 

1973 and served in that capacity until her retirement in 1981. 

Under her leadership, environmental contaminants research 

expanded and attained national prominence. The expansion of this program is demonstrated by the average number 

of publications on contaminants produced per year, which 

increased from 4 in the 1950s to 7 in the 1960s, and then to 

30 in the 1970s.

During the 1970s, all research and management activities related to the wetlands at Patuxent were curtailed because 

of new national priorities. This was a major turning point in 

the research on and management of the lands at Patuxent. 

Although biologists continued some activities with nest boxes 

and control of impoundment water levels on their own time, 

in general little on-site habitat research or management was 

conducted there during the 1970s.

Great egrets respond to moist-soil management, Patuxent Wildlife Research Center, Laurel, MD, 1987. Photo by 

Matthew C. Perry, U.S. Fish and Wildlife Service.
The Early Years of Patuxent Research

Patuxent’s Development: The People and the Projects 7

Frank McGilvrey and wood duck box, Patuxent Wildlife Research Center, Laurel, 

MD, 1972. Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.

In 1975, 1,250 acres of surplus land were transferred 

from the USDA to Patuxent, increasing the protection of 

Patuxent’s wetlands by ensuring control of more of the 

watershed. The MBHRL was disbanded in 1981, and migratory bird research staff and projects were returned to Patuxent 

Wildlife Research Center under the leadership of Dr. Stickel. 

Patuxent lands were used to study forest fragmentation and 

population modeling, which, along with statistical methodology development, were major migratory birds research thrusts 

in the 1980s.

Much of the other migratory bird research continued 

to be species-oriented (especially ducks), and little wetland 

habitat research was conducted on Patuxent lands during the 

1980s, although research was conducted in other areas, such as 

the work on waterfowl in the Chesapeake Bay ecosystem.

Patuxent’s first master plan was prepared in 1980. The 

research mission statement was “The professional staff is 

engaged in research and management activities that are 

directed at accomplishing the principal missions of the Center: 

evaluation of the effects of environmental contaminants on 

wildlife and the environment; endangered species research 

and propagation; and migratory bird research (including urban 

wildlife) and management.” A private consulting firm (Sasaki 

Associates, Inc.. Watertown, MA) wrote the master plan.

From 1982 to 1983, two acting directors, Drs. Russell J. 

Hall and John G. Rogers, Jr., who had been serving as assistant directors at the time of Dr. Stickel’s retirement, managed 

Patuxent. During this period, the Reagan administration was 

searching for Federal land that could be sold as surplus to 

meet government needs. Agencies were asked to identify land 

that could be considered surplus, and Patuxent complied by 

offering about 50 acres. Because Patuxent was officially part 

of the National Wildlife Refuge System, however, Congress 

controlled any land negotiations. With help from the Honorable Steny Hoyer, U.S. Representative from Maryland, loss 

of Patuxent land was forestalled. This threat to the land and 

pressures from the increasing human population around it 

(including housing development, road construction, and siting 

of a landfill) led administrators to reassess how the lands at 

Patuxent were being used.
8 The History of Patuxent: America’s Wildlife Research Story

Transition to Public Outreach

Dr. David L. Trauger was appointed Patuxent director in 

1983, following a 4-year stint as Chief, Division of Wildlife 

Research, in Washington, D.C. In 1984, planning began on 

obtaining a building for visitors at Patuxent, which had been 

discussed initially in the 1960s. Outside threats had been made 

to take over some of the land, but they were halted by the recognition that Patuxent was part of the refuge system. However, 

administrators realized that it was important that the public 

be aware of the value of wildlife research and the work of the 

USFWS in order to receive public support. A draft Public Use 

Plan for Patuxent dated 1985 states, “Overall Patuxent Wildlife Research Center has most of the key attributes of high 

potential for an excellent public use and educational program 

(as suggested in the 1984 FWS report to Congress...).” Given 

Patuxent’s location near two major metropolitan areas, it was 

ideally situated to comply with “....the policy of the Service to 

encourage resource-oriented public use on its lands that will 

provide the broadest array of opportunities for visitor enjoyment and that will facilitate understanding and awareness for 

natural resources within Service care.” The Section of Buildings and Grounds began a major reorganization to accommodate increased planning and land management responsibilities, 

and the first facility manager was hired in 1986.

In August 1987, Mr. Harold J. O’Connor became director 

of Patuxent. Mr. O’Connor was the first director with experience in the management of national wildlife refuges, and he 

was also a member of the Senior Executive Service. One of 

Mr. O’Connor’s first efforts was to obtain funding for the 

Visitor Center, which was being planned by his predecessor. 

Fifteen million dollars was obtained from Congress for this 

project, which evolved into a National Wildlife Visitor Center 

covering all wildlife research of the USFWS. The building 

was officially dedicated and opened to the public in October 1994, and has extensive exhibits depicting the wildlife 

research of the USFWS throughout the world. Researchers 

within and outside the Service are still conducting many of 

these research activities. Several support groups were established to help with fund raising and volunteer staffing of the 

Visitor Center, including the Prince George’s County Foundation and the Friends of Patuxent.

In 1988, Patuxent staff prepared a second master plan. 

The new plan stated that the mission of Patuxent “has 

remained unchanged since the submission of the original 

Master Plan report. It is essentially the same as for the overall 

U.S. Fish and Wildlife Service.” A later mission statement for 

Patuxent prepared in 1992 specifically included education and 

public use as important activities. This was a major change in 

the mission of Patuxent, but was responsive to public-use policies for the National Refuge System.

Several major rehabilitation projects involving 

impoundment control structures were undertaken under 

Mr. O’Connor’s direction. New experimental pens and ponds 

were constructed and the appearance of the grounds around 

the buildings was improved. Many dignitaries, including U.S. 

Senator Paul Sarbanes and U.S. Representative Steny Hoyer, 

attended a major celebration of Patuxent’s 50th anniversary on 

June 3, 1989. Senator Sarbanes, during his address, referred to 

the green forests of Patuxent as the “lungs of the Baltimore/

Washington region.”

Management of the wetlands and meadows became a 

formal activity with the implementation of impoundment 

and meadow management plans in 1989. A public fishing 

program in Cash Lake from June to October each year was 

initiated in 1991. A refuge biologist was hired to oversee all 

resource management activities, and the first refuge manager 

was appointed in 1992. These activities reflected the increased 

emphasis being placed on refuge management functions.

In 1991, 7,600 acres of land in Anne Arundel County that 

previously had been part of Fort George G. Meade, immediately adjacent to Patuxent to the north, were transferred 

to Patuxent because of the Military Construction Appropriations Act (U.S. Public Law 101-519). The U.S. Army, 

under the Base Closure and Realignment Act (U.S. Public 

Law 100-526), had declared the land excess. The transfer was 

based on the recommendations of a broad-based Fort Meade 

Coordination Council that had extensively studied the options 

and voted unanimously for the transfer. The transfer document 

specified that the intended priority uses of the property were 

preservation of the land, wildlife research, and compatible 

public use. In addition, the transfer document stated that the 

Secretary of the Interior “shall provide for the continued use 

of the property by Federal agencies to the extent such agencies 

are using it on the date of the enactment of this act.” Some of 

these activities were not compatible with wildlife and would 

not have been allowed on Federal refuges without the added 

wording. An additional 500 acres, including four softball 

fields, were transferred to Patuxent in 1992. These transferred 

lands are now called the Patuxent North Tract.

Map included in newspaper article on surplus Fort Meade lands, Maryland, 

1991. Reprinted with permission from The Baltimore Sun. All rights reserved.
The Early Years of Patuxent Research

Patuxent’s Development: The People and the Projects 9

Patuxent Visitor Contact Station on North Tract, Patuxent Wildlife Research 

Center, Laurel, MD, 1992. Photo by Matthew C. Perry, U.S. Fish and Wildlife 

Service.

The acquisition of these lands added the responsibilities 

of a major deer-hunting program (bow, gun, and muzzleloader) and increased public use and education. Other existing 

natural resource programs, including fishing, trapping for furs, 

and small-game hunting, were continued. Approximately half 

of the existing firing ranges continue to be used by defense 

and law-enforcement personnel for training under special-use 

permits with the National Security Agency and the U.S. Secret 

Service. Sport shooters under a special-use permit also used 

a trap and skeet range with a Goddard Space Flight Center 

shooting club. The range was later closed owing to concerns 

of lead poisoning, and study and remediation of lead contamination of the soil were conducted. A large, modern equestrian 

center was run by the U.S. Army’s Civilian Welfare Agency 

under a permit issued by Patuxent. The stable closed in 2004 

at the direction of the Fort Meade commander.

A Visitor Contact Station was constructed in 1993 on 

the new land to control public-use activities. This building 

was funded in part by the Prince George’s County Parks and 

Recreation Foundation, which was later instrumental in the 

establishment of the Friends of Patuxent, a 501(c)(3) refuge 

support organization. Minimal USFWS staff and volunteers 

operate the contact station, with occasional part-time support 

from USFWS law-enforcement personnel.

In 1990, when the major land transfer from Fort Meade 

was imminent, the Regional Director of Research and Development for the USFWS stated that no research funds would be 

used for management of the newly acquired lands. Administrators at Patuxent, therefore, were required to seek alternative 

funding for these activities. The extensive hunting program 

conducted at the North Tract of Patuxent was initially conducted through Fort Meade, but Patuxent assumed responsibility for the program after the transfer. The refuge initially 

issued a special-use permit and then entered into a Cooperating Association Agreement with a group of hunters who 

formed the Meade Natural Heritage Association (MNHA), 

which continues today (2016) to assist with day-to-day operations of the hunting program. MNHA assesses a permit fee 

for all hunters who are allowed to use the area after they have 

taken and passed the gun and (or) bow safety and proficiency 

training program.

Hunter fees are used to pay several employees, who 

manage daily hunting from the Hunting Control Station. Some 

remaining funds have thus far been put back into the Patuxent North Tract for erosion control, wildlife management, and 

other projects. Expenses borne by Patuxent for the hunting 

program are mainly for part-time salaries of law-enforcement 

personnel during the hunting season plus administrative support and oversight. The original directive from the Regional 

Director of Research and Development was subsequently 

changed, and Patuxent was authorized to spend $75,000 of 

research funding in fiscal years 1992 and 1993 to operate the 

North Tract.

The increased activities related to the Visitor Center and 

the increased use of public lands in the early 1990s exacerbated staffing problems at Patuxent and increased overhead 

expenses. The center’s staff was concerned about the lack of 

additional funding for administering the North Tract property, as well as the increased staff time devoted to developing 

the Visitor Center. As a result, in 1992 the USFWS director 

decided to transfer the administration of the new Fort Meade 

lands (North Tract) (8,100 acres) and the Visitor Center lands 

(South Tract) (2,000 acres) from Research Region 8 to the 

Division of Refuges in geographic Region 5. This transfer was 

to be effective in October 1993. Patuxent research staff would 

maintain control of the Central Tract (2,700 acres), where traditionally the researchers had been located and most of the onsite research had been conducted. Research staff would also 

still be responsible for management and public use on Central 

Tract lands. This decision received a mixed reaction from 

Patuxent employees, however, because there was no indication 

that increased funding would be forthcoming.
10 The History of Patuxent: America’s Wildlife Research Story

Transfer to National Biological Survey 

and then to U.S. Geological Survey

In March 1993, the DOI, headed by Secretary Bruce 

Babbitt, announced plans to form a new National Biological 

Survey (NBS) that would combine all biological research and 

monitoring within DOI into one bureau, separate from existing 

management bureaus. Opinion was divided on whether lands 

associated with Patuxent would be staying with the USFWS 

and be managed by the Division of Refuges or be transferred 

to the new NBS.

In November 1993, all research staff, many refuge staff, 

and several sections of the Office of Migratory Bird Management were transferred to the NBS. The new NBS organization 

also resulted in the transfer to Patuxent of one research unit of 

the National Park Service and all USFWS staff assigned to the 

Smithsonian Museum of Natural History. Although Patuxent administered 10 field stations in late 1993, realignment 

in the new NBS reduced the number of field stations to 4 in 

late 1994.

All lands and buildings of Patuxent continued to be 

officially controlled by the USFWS and within the Northeast 

Region 5 refuge organization. The actual maintenance of the 

buildings and management of the lands remained under the 

control of the director of Patuxent and his staff. This arrangement, in principle, provided protection of the land under 

all regulations and policies of the National Wildlife Refuge 

System, but gave maximum flexibility for use of the land for 

research purposes. This arrangement between the USFWS 

and the NBS was approved by Under Secretary of the Interior George Frampton, Jr., and was commonly called the 

Frampton Agreement.

On October 5, 1993, the Patuxent director announced a 

new strategic plan, which was to guide Patuxent’s activities 

in the NBS. The plan marked the beginning of the process 

to align Patuxent’s organization more closely with the NBS 

structure, which included major initiatives in surveying and 

monitoring habitats and populations and in transferring information and technology.

The primary mission of Patuxent as stated in the strategic 

plan was “to conduct biological studies in response to programs and priorities of the National Biological Survey (NBS) 

to support land and resource managers within the Department 

of the Interior. The Center will operate a National Biological 

Research area as an outdoor laboratory and operate the NBS 

National Wildlife Visitors [sic] Center for the advancement 

of environmental education and biological science.” A major 

change in the new mission of Patuxent in NBS was a reduced 

geographic responsibility to only the Eastern Ecoregion 

and a shift away from national and international initiatives. 

In May 1994, the name of the Patuxent Wildlife Research 

Center was changed to Patuxent Environmental Science 

Center. In late 1994, the name of the NBS was changed to 

the National Biological Service to address several concerns, 

including the assertion that new research was not supporting 

historical “customers.”

In March 1995, Patuxent’s director, Mr. O’Connor, 

retired from Federal service after 35 years. Dr. James A. 

Kushlan became director in late 1995 and, because of circumstances within the Federal government, Patuxent endured a 

disheartening period when budgets were cut and 26 personnel 

were officially relieved of their services (reduction in force). 

The Branch concept (three main groups: migratory birds, 

endangered species, and environmental contaminants) was 

abandoned and all research was placed under the control of 

a chief scientist. In the spring of 1996, the name “Patuxent 

Wildlife Research Center” was restored. In October 1996, 

the NBS was terminated and all research staff became part 

of the Biological Resources Division of the U.S. Geological Survey (USGS). Refuge staff returned to the USFWS 

under the Northeast Region (Region 5). The research operation (USGS) continued to be known as the Patuxent Wildlife 

Research Center, whereas the land ownership, management, 

and public-use operations were under the historical name of 

Patuxent Research Refuge. Each entity had its own administration and management, but they worked together to support 

Patuxent missions.

A Comprehensive Science Planning Process, which 

included five themes that overlap the scientific activity areas 

chosen by the Biological Resources Division, was developed 

under Dr. Kushlan’s leadership. The new mission for Patuxent 

was “to excel in wildlife and natural resource science, providing the information needed to better manage the Nation’s 

biological resources.”

In 2001, Dr. Kushlan resigned his position as director of 

Patuxent Wildlife Research Center; later that year, Dr. Judd 

A. Howell became the new director. Dr. Howell conducted a 

review of the organization and made changes following guidelines from headquarters that provided more program managers 

and more accountability from the Patuxent Wildlife Research 

Center staff and activities. Research staff was consolidated 

into Gabrielson Laboratory and a rented building at the Beltsville Agricultural Research Center. In spite of the division into 

two agencies, Patuxent’s staff was optimistic that problems 

with facilities and responsibilities would be resolved, and they 

continued to work closely together. A joint Facilities Modernization Program was developed over the years to address the 

future facilities and infrastructure needs of the agencies.

In 2009, Dr. Gregory Smith assumed the position of 

director of Patuxent Wildlife Research Center. During this 

period, due to economic recovery programs (American Recovery and Reinvestment Act) throughout the United States, 

Patuxent was involved in the removal of some buildings and 

the planning of construction of new buildings. Dr. Smith led 

this initiative in close coordination with Mr. Bradley A. Knudsen, manager of the Patuxent Research Refuge. The refuge 

was going through a major comprehensive planning process, 

so the timing of the activities complemented each other. 

Patuxent made plans for an addition (annex) to Gabrielson 
The Early Years of Patuxent Research

Patuxent’s Development: The People and the Projects 11

Laboratory that would greatly increase the ability of the 

research facility to continue with its research mission. The 

USFWS continued planning for new facilities, some of which 

would accommodate USFWS personnel from other facilities, 

especially the Chesapeake Bay Program, now located in rental 

space in Annapolis, MD. In 2014, Dr. Smith died while on 

official travel in China. Former director Dr. Judd A. Howell 

volunteered to fill the director position temporarily. A new 

director, Dr. John B. French, was appointed on May 26, 2015.

From a humble beginning with 2,670 acres of land in 

1936, Patuxent has increased in size over its 80-year history 

to the present (2016) 12,841 acres. Much of the early land 

development was done under the direction of a superintendent, Dr. Morley. Nine research directors have succeeded 

Dr. Morley in supervising the research program; most of 

them were in charge of land development and maintenance. 

In 1994, however, all land-management activities came under 

the jurisdiction of the refuge manager under the USFWS, with 

the research program being placed in the USGS. The Patuxent 

Wildlife Research Center and the Patuxent Research Refuge 

are closely related, and the facility has operated in most cases 

as one unit. After more than 80 years, the staff, collaborators, 

and friends around the world simply refer to this facility, with 

pride and respect, as “Patuxent.”

References Cited

Allen, D.L., 1949, The farmer and wildlife: Washington, D.C., 

Wildlife Management Institute, 82 p.

Allen, D.L., 1954, Our wildlife legacy: New York, Funk and 

Wagnalls, 422 p.

Crissey, W.F., 2006, A life like no other—The autobiography 

of Walter F. Crissey: Bloomington, IN, iUniverse, Inc., 

468 p.

Hotchkiss, Neil, and Stewart, R.E., 1947, Vegetation of the 

Patuxent Research Refuge, Maryland: American Midland 

Naturalist, v. 38, no. 1, p. 1–75. [Also available at http://

dx.doi.org/10.2307/2421630.]

McGilvrey, F.B., and Uhler, F.M., 1971, A starling-deterrent 

wood duck nest box: Journal of Wildlife Management, 

v. 35, no. 4, p. 793–797. [Also available at http://dx.doi.

org/10.2307/3799789.]

Morley, L.B. [sic], 1948, Early history of Patuxent Wildlife 

Research Center (circa 1948): U.S. Geological Survey, 74 

p., accessed October 3, 2011, at http://www.pwrc.usgs.gov/

history/cronhist/Morley4.pdf.

Perry, M.C., Kangas, P., and Obrecht, H.H., III., 2000, 

Creating and managing wetland impoundments to provide 

habitat for aquatic birds, in Comin, F.A., Herrera, J.A., and 

Ramirez. J., eds., Limnology and aquatic birds monitoring, modelling and management: Universidad Autonoma 

de Yucatan, International Symposium on Limnology and 

Aquatic Birds, Monitoring, Modelling, and Management, 

2nd, Merida, Mexico, November 24–27, 1997, p. 261–279.

Stewart, R.E., Cope, J.B., Robbins, C.S., and Brainerd, J.W., 

1952, Seasonal distribution of bird populations at the 

Patuxent Research Refuge: American Midland Naturalist, 

v. 47, no. 2, p. 257–363. [Also available at http://dx.doi.

org/10.2307/2422265.]

Warbach, Oscar, 1958, Bird populations in relation to 

change in land use: Journal of Wildlife Management, 

v. 22, no. 1, p. 23–28. [Also available at http://dx.doi.

org/10.2307/3797292.]
12 The History of Patuxent: America’s Wildlife Research Story

Snowden Hall, Patuxent Research Refuge, Laurel, MD. Photo by Bureau of Biological Survey.
The Early Years of Patuxent Research

Early Avian Studies at Patuxent

Chandler S. Robbins

When I arrived at Patuxent Research Refuge (Patuxent) in 

Maryland in the spring of 1943, I was amazed to find that the 

refuge, barely 6 years old, had already been surveyed with a 

100-meter (m) (325-foot [ft]) grid. The presence of permanent 

survey markers every 100 m and trails throughout the grid provided an ideal situation for recording the precise position of all 

wildlife observations. The grid system was so well coordinated 

with construction of the laboratory buildings that wherever a 

grid line passed through a building, a marker showing the passage of the line through the building was inserted in the brick 

wall. Wherever a grid line crossed the Patuxent River, an extra 

survey marker was placed on the riverbank, but most of these 

river-crossing posts were washed away in subsequent floods.

I was impressed with the expertise and dedication of the 

young professional staff. Superintendent Leland Morley and 

veterinarian Don Coburn had veterinary degrees, but I do not 

believe a single staff member at that time had a Ph.D. degree, 

unless it was a chemist. I was also impressed with the national 

collections of bird and mammal skins, reptiles and amphibians, 

and seeds and pressed plants that were being used to identify 

stomach contents.

Four major programs of the former Bureau of Biological 

Survey had been moved from Washington, D.C., to Patuxent (which at that time had a Bowie, MD, address): the Bird 

Banding Laboratory and the Bird Distribution and Migration 

Files and species maps, under Frederick C. Lincoln; the Mammal Files, including bat banding records, under Hartley H.T. 

Jackson; and the Food Habits records. The bird and mammal 

offices were in the Bird and Mammal Laboratory (later called 

Nelson Laboratory), the Food Habits staff and all the specimen 

collections were in the Food Habits Laboratory (later referred 

to as Merriam Laboratory), and the veterinary staff was in the 

Disease Laboratory (which became Henshaw Laboratory).

The Biological Survey’s Division of Economic Ornithology and Mammalogy had been conducting food habits studies 

of birds and mammals since 1885 to determine which species 

were useful to agriculture. By 1943, most of the effort was 

devoted to teaching biologists from various states the techniques of examining stomach contents and identifying the fragments of insects, arthropods, seeds, and other material. When 

Congress suspended all funding for food habits studies in 

1943, this work suddenly stopped. The stomach material that 

had been examined was offered to the states from which it had 

come, but all the examination cards were retained at Patuxent.

U.S. Biological Survey plot marker at Patuxent Research Refuge, Laurel, MD. 

Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.

Bird Banding

The Bird Banding Laboratory

Shortly after passage of the Migratory Bird Treaty Act 

with Canada in 1916, it was determined that bird banders 

should be licensed under Federal permits, so the banding 

program was moved from the auspices of the American Bird 

Banding Association to the U.S. Biological Survey in 1920 

under the supervision of Fred Lincoln. When the program was 

moved to Patuxent in 1936, Fred Lincoln and his secretary, 

Myra Putnam, retained their offices in Washington, D.C., but 

Mr. Lincoln made frequent visits to Patuxent, where May 

Thacher Cooke (daughter of the late Wells W. Cooke of the 

Biological Survey) was in charge of the daily operations.

My first assignment at Patuxent was as a biologist in the 

Banding Laboratory, checking incoming schedules and coding 
14 The History of Patuxent: America’s Wildlife Research Story

return records for keypunching. I was already familiar with 

the species codes (American Ornithologists’ Union [AOU] 

numbers) and most of the other codes from my previous 

6 years as a bird bander. The principal codes I had to look up 

on the code board were IBM Corporation’s (IBM’s) threedigit numerical code for North American localities (such as 

717 for Patuxent); we were not using latitude and longitude 

in those days. In 1943, we did not yet have a keypunch or a 

card-sorting machine.

The only other people in the Banding Laboratory in the 

1940s were processing clerks Margery Stewart and Lois Horn, 

and mail carrier and band issuer Russell Carpenter. Each 

morning Russell stopped at South Interior Building to pick 

up the mail on his way to work because the bands carried a 

Washington, D.C., address. After May Cooke retired and Fred 

Lincoln was moved to the Chicago office, John Aldrich at the 

National Museum of Natural History handled administrative 

matters for the Banding Laboratory and I continued as biologist. I had been concerned about the future of the songbirdbanding program because our staff was insufficient for the 

workload and the waterfowl people insisted that processing of 

waterfowl records should take priority. We were accumulating 

a sizable backlog of unprocessed songbird records. When I 

heard that we were about to advertise a position for a banding 

chief, I telephoned Seth Low, Refuge Manager at Salt Plains 

National Wildlife Refuge in Oklahoma, whom I had known 

when he worked at the Austin Ornithological Research Station 

on Cape Cod, MA, and urged him to apply because of his 

interest in songbird banding as well as his lengthy experience as a waterfowl bander. Seth was offered and accepted 

the position, along with all its related problems, but songbird 

banding survived.

Ruth Richards worked part time with the Bird Distribution and Migration program, sending and acknowledging the 

2-in. × 5-in. observation cards and assembling certain records 

for publication. She spent the remainder of her time working 

with Hartley Jackson’s mammal files.

Songbird Banding

Leonard Llewellyn, Royal Stewart, and R.N. Crack were 

the first to band a few Patuxent birds in 1940, 1941, and 1942. 

From 1943 to 1946, Robert Stewart, James Cope, John Brainerd, and I trapped and banded thousands of songbirds using 

conventional traps baited with grain or dripping water. We 

recorded the grid-cell number of each bird banded in order 

to study movements through the recaptures. Father Fabian 

Kekich at Catholic University in Washington, D.C., had 

been having amazing success in baiting migrating warblers 

with dripping water in top-opening traps. When he moved to 

another location he kindly gave us all his traps, but we could 

not match his wooded hilltop in an urban location and never 

had the concentration of migrating warblers that he enjoyed.

In 1959, Donald Stamm, David Davis, and I began a 

breeding bird study in deciduous forest in and near the flood 

plain of the Patuxent River (3600 block of the Patuxent grid), 

Chan Robbins banding songbirds, Patuxent Research Refuge, Laurel, MD, 1948. 

Photo by U.S. Fish and Wildlife Service.

which continued through 1972. For 6 or more days each season, birds captured in mist nets were identified, banded, and 

released; the date, time, and location of all initial captures and 

recaptures were recorded. This study was among the first to 

use capture-recapture methods to estimate population size for 

various bird species (Stamm and others, 1960).

Raptor Banding

Ira Gabrielson had been impressed by the high density 

of hawks and owls at Patuxent, as had local falconers. John 

Hamlet, in particular, was a frequent visitor who helped us use 

various techniques to trap and band a few hundred resident 

and migrating raptors. We were most successful with the 

Verbail pole trap and operated these night and day, checking at 

sunrise and several times during the day in 1943–45. Nestling 

red-shouldered hawks (Buteo lineatus) were banded each year, 

and especially in 1947 when Burt Taurman was a summer student. Of 107 nestling red-shoulders banded in 1947 in stream 
The Early Years of Patuxent Research

Early Avian Studies at Patuxent 15

valleys in and near Patuxent, 9 were shot and another was 

found dead in the next 2 years, all in Maryland.

Operation Recovery

Shortly after Oliver L. Austin, Jr., introduced the use 

of Japanese mist nets to North America and banders began 

flocking to coastal beaches to capture grounded migrants, I 

joined Massachusetts Audubon Society scientists James Baird, 

Aaron Bagg, and John Dennis (Baird and others, 1958) in 

promoting a cooperative coastal banding program during fall 

migration. We called it Operation Recovery with the expectation that, with enough songbirds being banded at coastal sites, 

we should be able to recapture banded birds farther south in 

the same season and determine how far they were flying in a 

single night. Furthermore, to participate in the study, banders 

were required to keep a record of the number of net-hours of 

effort each day and to weigh their birds, record wing chord, 

and determine age and sex when possible. This was the first 

time banders had ever been required to keep track of banding effort, to weigh their birds, or to make a special effort to 

determine age and sex. This was just before I published my 

key to aging and sexing of wood warblers in fall (Robbins, 

1964). To our surprise, the first recaptures of banded birds 

occurred north of where they had been banded, showing that 

many migrants routinely wander northward before initiating 

their southward migration.

Many other surprises followed. Considering only those 

from Maryland, on September 17, 1965, Operation Recovery captured at Ocean City the first hybrid between a northern waterthrush (Parkesia noveboracensis) and a blackpoll 

warbler (Dendroica striata) (Short and Robbins, 1967). Four 

western wood-pewees (Contopus sordidulus), the first for the 

Atlantic Coast, were caught at Ocean City on four September 1961 dates; a western tanager (Piranga ludoviciana; first 

Maryland record) was banded on October 21, 1962; a rufous 

hummingbird (Selasphorus rufus; first Maryland record) was 

banded on September 12, 1963; and a Hammond’s flycatcher 

(Empidonax hammondii; first East Coast record) was captured 

on October 9, 1963. More first-year birds were captured at 

coastal locations, where survival rates were lower, than at 

inland ones (Robbins and others, 1959). 

Operation Recovery also collected thousands of ticks 

from the ears of migrating birds (Clifford and others, 1969). 

When an impatient bander complained to the Director of 

the U.S. Fish and Wildlife Service (USFWS) that I was late 

in publishing a summary of results, the Director wrote me 

that we should not be studying fall migration of songbirds 

and I should cease immediately. Therefore, the large, bound 

tabulations of weights and wing chords of North American 

fall migrants lie unpublished in the Patuxent library. Several 

of the coastal banding stations eventually became full-time 

bird observatories, and I believe that one of the great contributions of the Operation Recovery program was the training of 

hundreds of banders in aging and sexing fall migrants and in 

recording their banding effort.

Evolution of the Bird-Banding Record Card

Houston and others (2008), in “History of ‘computerization’ of bird-banding records,” discussed successive changes 

in the design of the bird-banding schedule, but we authors 

neglected to mention the changes that had been made to the 

design of the return card. The cards are now history. Essentially all were destroyed when we made the transition to totally 

electronic files.

Prior to 1929, a printed 3-in. × 5-in. card was used for 

each recapture and each recovery record of a banded bird. 

Beginning in 1929, each record was placed on an 80-column, 

3.25-in. × 7.375-in. punch card on which the vital banding 

and recovery data were handwritten in labeled spaces in the 

first 36 columns, and the remaining columns were reserved 

for future keypunching of the same information. The card 

was reprinted, unchanged, in October 1939 and September 

1941. In April 1950, the handwritten portion was redesigned 

to add an eighth digit to the band number, to include codes for 

Jerry Longcore capturing woodcock with mist nets, Milford, ME, 1998. Photo 

by Daniel McAuley, U.S. Geological Survey.
16 The History of Patuxent: America’s Wildlife Research Story

hand-reared and sick or injured birds, to change the position 

of categories in the handwritten portion of the card, and to 

provide for the permit number, but the punch holes were not 

altered except to replace “FY Rec’d” with “Elapsed Time.” 

In an August 1953 revision, the card was made more user 

friendly, providing for easy reading of an “interpreted” card; 

“Operator” was finally replaced by “Permit No,” “Schedule 

No.” was omitted, and the handwritten portion of the card 

was neatly rearranged with banding information at the top and 

recovery information below.

In January 1955, the handwritten portion of the card 

disappeared, the positions of all the columns were changed, 

and new categories were added for “Status,” “Letter Received 

Date,” and “Previous Reports.” “Latitude” and “Longitude” 

were substituted for the alphabetical abbreviations of “Where 

Banded” and “Where Recovered.” For the first time, “U.S. 

Fish and Wildlife Service” and “Canadian Wildlife Service” 

appeared on the punch card. Another revision in July 1959 

added columns for “Additional Information,” “Dir. Banding,” 

“Dir. Recovery,” “Who Reported,” and “Hunting Season.” The 

last seven columns of the card remained vacant.

Other Bird Monitoring

Initial Avian Studies on the Patuxent Grounds

The only avian publication that originated at Patuxent prior to 1943 was a Christmas Bird Count (49 species, 

2,475 individuals). This count was conducted within the 

Patuxent boundaries on December 23, 1941, by bird enthusiasts John Aldrich, Leo Couch, Lucas Dargan, Herbert 

Deignan, John Hamlet, Neil Hotchkiss, Phoebe Knappen, 

Leonard Llewellyn, Alexander Martin, Franklin May, George 

Petrides, Robert Smith, Robert Stewart, and Francis Uhler. 

We resumed Christmas Bird Counts in 1943, and they are still 

conducted annually within the original 2,670 acres as part of 

the Bowie, MD, 7.5-mile (mi)-radius circle.

At the same time, Patuxent staff members (primarily 

Ira Gabrielson, Clarence Cottam, Francis Uhler, and Arnold 

Nelson) had been conducting a carefully controlled Christmas count in a 20-year study (1927–46) at Port Tobacco in 

Charles County, MD, to determine whether changes in winter 

bird populations could be detected if an area was carefully 

covered the same way on foot each year by (primarily) the 

same four people. One year, I was invited to be one of the 

four participants, and was shocked to find that they would not 

accept observations unless the bird was identified by sight. If 

a jay or an owl was heard, or if a woodpecker called, it could 

not be counted unless it was identified by sight. At the end of 

the 20 years, the observers did not detect changes over time 

and determined that their results were not worth publishing. If 

they had continued a few more years, they would have noted 

major changes in populations of eastern bluebirds (Sialia 

sialis), Carolina wrens (Thryothorus ludovicianus), loggerhead 

shrikes (Lanius ludovicianus), and several other species.

The Vegetation Map and Documentary Bird 

Surveys

A colored vegetation map of the entire refuge was completed in 1943 by observers walking the grid lines, pacing the 

distance to each change in habitat, and recording the results on 

1-kilometer (km) (0.6-mi) field maps. The next major task was 

for biologists Robert Stewart, John Brainerd, James Cope, and 

me to hike the same grid lines during the 1943 nesting season, 

recording on the 1-km sectional maps the location where each 

bird was detected. The entire refuge was covered three times: 

in April for raptor and crow nests, in May for woodpeckers 

and early-nesting Passeriformes (passerines), and in June for 

most other nesting species. Special trips were made in July 

to areas where the late-nesting American goldfinch (Carduelis tristis) and cedar waxwing (Bombycilla cedrorum) were 

found. These detections were then transferred to black-andwhite copies of the vegetation map to show the distribution of 

each species by habitat.

In the next two winters, the same four observers mapped 

the winter distribution of each bird species. Our awareness that 

winter populations are much more variable from year to year 

than are breeding populations explains the additional year of 

mapping in winter.

Botanist Neil Hotchkiss surveying plants, Patuxent Research Refuge, Laurel, 

MD, 1946. Photo by Francis M. Uhler, Patuxent Research Refuge.
The Early Years of Patuxent Research

Early Avian Studies at Patuxent 17

Colored vegetation map of original 2,670 acres at Patuxent Research Refuge, Laurel, MD. Illustration by U.S. Soil 

Conservation Survey, Washington, D.C., 1945.
18 The History of Patuxent: America’s Wildlife Research Story

To continue studying changes in Patuxent bird populations, we conducted a “population fluctuation census” that 

tracked population changes by habitat weekly (twice weekly 

during the peaks of the spring and fall migrations) throughout 

2 years over a 2.6-mi transect in the center’s headquarters 

area. The transect began in the historic pear orchard of the 

Snowden family just north of Snowden Hall, proceeded due 

west through Ralph Nestler’s quail pens to the west boundary fence, then extended north parallel to the fence into the 

flood plain, then east for nearly 1 mi through the flood plain, 

then south through the large fields to Snowden Brook, and 

west up the Snowden Brook valley to the new Entrance Drive. 

This survey was run by three observers walking parallel paths 

100 m (325 ft) apart and keeping records by habitat. Results of 

the breeding and winter counts, population changes throughout the year, and a detailed species account for the 229 species 

that had been recorded at the refuge were published by Stewart 

and others (1952), but the habitat records from the population 

fluctuation census have never been published. Bob Stewart 

took the notebooks with him when he moved to the Northern 

Prairie Wildlife Research Center (Jamestown, ND), intending 

to publish the results; after his death in 1993 the notebooks 

were returned to Patuxent, but other priorities have prevented 

their publication.

Territory Mapping

The next field research was selecting study sites typical of each of the major Patuxent habitats (flood-plain forest, 

oak-beech river terrace forest, Virginia pine (Pinus virginiana) 

forest, upland oak forest, and abandoned field) and conducting 

spot-mapping censuses in each. From 8 to 40 or more census 

trips were made to each site using the method of Williams 

(1936), except that special emphasis was given to recording 

simultaneous registrations of males in adjacent territories. 

From repeated census trips to the same site, we could determine the probability of detecting each species on a single visit; 

probabilities ranged from 36 percent for worm-eating warbler 

(Helmitheros vermivorum) to 81 percent for hooded warbler 

(Setophaga citrina). I helped Donald Thatcher of Washington, 

D.C., Audubon Society to set up a long-term census site in 

the Potomac River flood plain for comparison with Patuxent, 

and Joan Criswell, one of my students at the U.S. Department of Agriculture Graduate School (now Graduate School 

USA) in Washington, D.C., set up a site in nearby Rock 

Creek Park that was censused for many years and was the first 

such site to demonstrate the decline in wood thrushes (Hylocichia mustelina) and other Neotropical migrants (Briggs and 

Criswell, 1979).

Nest Record Cards, 1940s–50s

Bob Stewart designed a two-sided 3-in. × 5-in. nest 

record card with space for species, location, habitat, contents, 

and observer name on the front and space for 10 subsequent 

observations on the back (Stewart and Robbins, 1958). The 

same card was used to record historical information from 

throughout Maryland. The file now contains tens of thousands 

of records that I hope can be digitized someday. This file was 

the basis for the nesting paragraphs in the first Maryland/D.C. 

breeding bird atlas. The second atlas contained primarily generalized nesting information from out-of-state sources.

Field-Testing of the Mourning Dove Call Count 

Procedures 

Harold Peters and Leonard Foote had been designing 

procedures for a national call count survey of breeding mourning doves (Zenaida macroura). The plan was to have twenty 

3-minute roadside stops 1 mi apart, but the best starting time 

was undecided. They planned to do final field testing in Georgia and asked Allen Duvall and me to run sample routes in 

Maryland and Pennsylvania, where the twilight time is longer 

and where early-morning traffic might be a greater problem. 

Their conclusion and ours were the same: that the best results 

were obtained when the survey started 30 minutes before sunrise. However, when we put the starting time to a vote, it was 

3 to 1 in favor of starting at sunrise “because you can’t ask the 

State biologists to get up that early.” Now, 45 years later, we 

still begin the survey at sunrise.

“The DDT Years,” 1945–49

On June 5, 1945, at the height of the breeding season, 

a 117-acre tract of the forested refuge just downstream from 

Duvall Bridge was sprayed just above treetop level with 1 

pound of dichlorodiphenyltrichloroethane (DDT) per acre 

(Robbins and Stewart, 1949). We had insisted that this site, 

where the Patuxent River leaves the refuge, should be the 

site of the aerial spraying, in order not to contaminate the rest 

of the refuge. A study site had been established in the center of the sprayed area, and two control sites had also been 

established, one adjacent to the sprayed area and about 1 mi 

upstream. The bird crew (Stewart, Cope, Brainerd, and I) conducted breeding bird censuses in all three study plots before 

and after spraying. Except for the American redstart (Setophaga ruticilla), a treetop feeder, no change in breeding population or in hatchability of eggs or survival of nestlings could 

be demonstrated. Subsequent aerial sprayings of 2 pounds 

of DDT per acre in May or early June of 1946 through 1949 

caused substantial declines immediately after spraying only in 

the American redstart. It was determined that most of the spray 

was captured by leaves in the canopy, so little of it reached the 

understory where many of the birds were foraging and nesting 

(Robbins and others, 1951).

In 1947, a 90-acre area of scrub forest on the nearby 

USDA Agricultural Research Center that was recovering from 

a 1942 forest fire was sprayed with 5 pounds of DDT per acre 

to study effects of DDT in an open environment. Bird populations were studied in a 30-acre plot in the center of the sprayed 
The Early Years of Patuxent Research

Early Avian Studies at Patuxent 19

area and in a 30-acre unsprayed plot 0.5 mi away. Of the five 

most common species in the sprayed area, the common yellowthroat (Geothlypis trichas), prairie warbler (Setophaga 

discolor), and house wren (Troglodytes aedon) were reduced 

80 percent and the eastern towhee (Pipilo erythrophthalmus) 

was reduced apparently 65 percent, whereas there was no 

appreciable change in number of yellow-breasted chats (Icteria virens).

In the meantime, DDT studies based on manual applications on active bird nests were conducted to determine 

whether eggs and young would survive (Mitchell and others, 

1953). With a nesting population of color-banded eastern 

bluebirds and house wrens available, I could not resist the 

temptation to follow two populations over a 3-year period. The 

bluebirds were especially interesting in that both adults and 

young returned to nest at the same site year after year. Soon 

most of the birds were related to each other. At a meeting of 

the North American Bluebird Society, I shocked the membership by showing that a 1-year-old male bluebird was mated to 

his grandmother. I started a long-term study of nesting barn 

swallows (Hirundo rustica) in the Hance Farm barn, but it was 

terminated in the second year when the barn was boarded up.

Studies of Nocturnal Bird Migration

Patuxent researchers installed a U.S. Navy (Navy) radar 

system outside Nelson Laboratory in 1945 in the hope of 

detecting songbirds flying at night, but it turned out to be 

the wrong type of equipment and I could not detect anything 

smaller than the Chesapeake Bay Bridge, so we had to resort 

to less technical methods.

Bob Stewart and I made many trips to the Washington 

Monument on cloudy, moonless evenings in the autumns of 

1945 and 1946 to study migrating birds that struck the monument in the hours before midnight, while the spotlights were 

on. The birds were attracted to the monument by the spotlights; they tried to fly to one side or the other, but were swept 

by the wind against the backside with enough force to produce 

concussions, and they fell to the ground. We got permission 

from the Park Police to drive our vehicle to the base of the 

monument so we could immediately put the birds in cages. 

Any survivors were released the next morning at Patuxent. 

We made study skins of the casualties. We learned many of 

the night call notes (which were generally different from the 

familiar diurnal calls) by listening to and watching the birds as 

they collided with the monument.

In a separate study, I joined 2,500 observers throughout North America in a cooperative study of bird migration 

organized by George Lowery and Robert Newman of Louisiana State University (Baton Rouge). They solicited observers 

to make all-night counts of birds flying across the face of the 

full moon. The birds were visible for only an instant as they 

crossed the moon, but the birds seen provide an index to the 

vast number that are unseen. The organizers had developed 

equations to translate the number of birds seen to the number 

that had crossed a 1-mi-long line centered on the observer, 

corrected for the latitude of each observer. On the night of 

September 22–23, 1953, using a wire recorder, I counted 

2,188 birds flying overhead, which translated to 230,000 birds 

crossing a 1-mi-long line centered on my driveway. That was 

the highest count ever recorded in North America (Lowery 

and Newman, 1955).

Breeding Bird Survey

In the early 1960s, DDT was still widely used to control 

insects on college campuses, and each application resulted in 

distressed and dying robins and other songbirds. One woman 

in the Midwest was concerned about the future of songbirds 

in North America and wrote to inquire whether the loss of 

nesting birds on campuses across the country was sufficient to 

affect continental populations. I replied that at present, there 

was no continental survey that could answer that question, but 

I said I would give it some thought. We did have waterfowl 

surveys, but they did not reveal anything about songbirds. 

There were Federal game agents and State agents, but most of 

them had no experience with songbirds. The only hope would 

be to find enough trained bird enthusiasts who would be willing to conduct rigid surveys over a period of years.

I proposed a plan to the Maryland Ornithological Society 

(MOS) that could allow me to hand-pick qualified observers; assign 50 random roadside routes of 50 stops each, 

0.5 mi apart, throughout the State; and have each observer 

run a “check route” that I had run in addition to his or her 

own assigned route. Jack Linehan offered to recruit observers for 10 Delaware routes as well, and all 60 routes were run 

successfully in 1965. The number of birds recorded on the 

50 Maryland routes was 50,373, or an average of 1,007 individuals per route. The observers enjoyed the experience and 

were prepared to run the same routes the next year.

The next question was whether Patuxent would be willing to take the responsibility of running a national breeding 

bird survey program and whether Canada would be willing to join in. I explained the success of the 1965 trial to 

John Aldrich, my supervisor; told him of my plan to expand 

gradually across the continent in the next 3 years; and asked 

his opinion. His considered reply was, “Go for it—just so it 

doesn’t cost the government any money.” I had all the help 

I needed: a full-time secretary (Romell Decker); a full-time, 

experienced map expert (Ceil Nalley); a programmer (John 

McDaniel); plenty of keypunch time (during the lax bandingrecovery period of summer); free phone service; and free 

mail. We needed only to design forms to use in the field, select 

random starting points for the survey routes, and draw the 

route paths. Tony Erskine was eager to act as my Canadian 

counterpart. The rest is history. My brother Sam had already 

started a State monitoring program in Wisconsin based on 

observer-selected sites in 1961, but he recognized the value 

of a randomly distributed sample, so he was glad to change to 

our random design.
20 The History of Patuxent: America’s Wildlife Research Story

Data Bank of North American Breeding Bird 

Censuses

In 1973, the USFWS began a program of computerizing 

breeding bird census data (Robbins, 1977). Initially, data from 

1,939 census studies representing 801 different plots from 

1937 to 1970 were coded and keypunched onto magnetic tape. 

Subsequently, data from 1971 to 1975 were added. Each plot 

was assigned a permanent number. A bound computer printout 

of this file can be found in the Patuxent library.

Winter Bird Survey of Central Maryland

The Winter Bird Survey (WBS) was designed to sample 

midwinter bird populations and to determine how well the 

Audubon Christmas count sampled year-to-year changes. The 

validity of the Christmas count had been questioned because 

the areas covered were selected rather than random, coverage was a mixture of walking and driving, and the number of 

hours of effort varied among observers. To control the coverage, each WBS observer walked a predetermined 8-km (5-mi) 

closed-circuit course in 4 hours, beginning at 7:30 a.m. The 

area selected for this study extended from Chesapeake Bay 

west to the base of Catoctin Mountain and from the Potomac 

River north to the Pennsylvania border. Location of counting 

areas was by a systematic sample, with one route located at 

the center of each 71⁄2-minute U.S. Geological Survey (USGS) 

quadrangle. Each of the 40 routes was covered one morning 

per winter from January 15 to February 15. The method was 

tested in the Laurel quadrangle in the winter of 1968–69 by 

Patuxent staff. We compared the WBS results with those of 

the four Christmas counts made each year in the same geographic area. For most species, the WBS totals were higher 

than the Christmas count totals because the WBS counts were 

made entirely on foot; it was primarily the feeding-station 

birds that were found in higher numbers on the Christmas 

count. The close correlation between the two methods in 

1970–74 indicated that Christmas count data for past decades 

might be a valuable index to population change, even though 

these data cannot in themselves be subjected to critical statistical analysis.

Woodcock, Snipe, and Clapper Rail Surveys

Most of the woodcock survey work was conducted on 

the breeding grounds in the Northeastern States and eastern 

Canada, but the reports were compiled and edited at Patuxent (Aldrich and others, 1952). Bob Stewart estimated the 

breeding population of American woodcock (Scolopax minor) 

at Patuxent to be 25 territorial males in 1942, decreasing to 

21 pairs in 1943, 8 in 1947, and 9 in 1951. The large reduction from 1943 to 1947 was probably almost entirely due to 

“clearing in connection with farm wildlife experiments, but 

partly also from natural succession” (Stewart, 1952). Roadside 

routes in the Maryland suburbs were later abandoned because 

of traffic noise.

Initially there were no consistent common snipe (Gallinago gallinago) surveys, but snipe hunting could not be permitted on the Gulf Coast wintering grounds unless a USFWS 

biologist was conducting population studies on this species. 

Therefore, I established a cooperative winter survey program 

in the Southern States in 1953; banded snipe at winter concentration spots including coastal Florida, Mobile Bay, and 

Sabine Refuge in Louisiana (1950–55); and spent the summers 

of 1952–54 studying nesting snipe at Midgic Marsh in New 

Brunswick, Manitoulin Island in Ontario, and across upper 

northwestern Canada.

Bob Stewart (1952) studied clapper rails (Rallus longirostris) nesting at Chincoteague, VA, in 1950–51, and trapped 

and banded 940 of them. Hunters reported 10 recoveries 

(5 percent) from the 198 birds banded in 1950.

Geographic Variation in Bird Song

I had long been interested in geographic differences in 

bird songs. As a teenager, a neighbor (Ingraham, 1938) had 

given me a tuning fork and encouraged me to record the exact 

pitch of songs of wild birds. In New England, the ovenbird 

(Seiurus aurocapilla) says “tea’-cher, Tea’-cher, TEA’-

CHER,” as described in the field guides, but in other regions 

it says “teacher’, Teacher’, TEACHER’,” and in Maryland it 

says “teach, Teach, TEACH.” In all geographic regions, the 

increase in volume as the song progresses is diagnostic of 

the species.

In the summer of 1954, when I was studying snipe distribution across Canada at dawn and dusk, I used the long summer days to make tape recordings of bird songs to study differences in dialect from east to west. When it was not convenient 

for me to access my tape recorder and parabola, I carried a 

supply of index cards in my pocket to record the cadence 

(songs per minute), temperature, and locality of singing birds 

because I had not seen this information published previously. 

I tried for a series of 11 consecutive songs (10 intervals) from 

each bird. Patuxent biologist Sam Droege subsequently digitized this file.

Many more interesting experiences followed, including 

my long-term banding and population study of the breeding 

birds in a 90-acre plot in the Patuxent River terrace forest and 

the effect of forest fragmentation on nesting songbird populations in a random sample of 469 Maryland forests. I also 

trained Latin American scientists in bird census and banding 

techniques in nine Latin American countries. I returned to six 

Allegheny County forest study sites I had censused 50 years 

previously to conduct wind turbine studies, and I helped with 

the Breeding Bird Atlases in Maine, New Hampshire, Pennsylvania, Maryland, and West Virginia to demonstrate the need 

for habitat protection here at home.
The Early Years of Patuxent Research

Early Avian Studies at Patuxent 21

Collaboration

Collaboration with the Audubon Society of the 

District of Columbia

In 1947, Bob Stewart, John Aldrich, and I collaborated 

with three Washington, D.C., Audubon Society members to 

produce their first “A Field List of Birds of the District of 

Columbia Region.” In 1951, Shirley Briggs and I edited their 

habitat pamphlet, “Where Birds Live: Habitats in the Middle 

Atlantic States.” I wrote their monthly season reports from 

1946 to 1948 and their bimonthly reports from 1948 to 1949, 

as well as a Hawk Watch article for their “Atlantic Naturalist” 

journal in 1956.

Collaboration with the National Audubon 

Society

Shortly after Joseph Hickey wrote his “Guide to Birdwatching,” he and his wife, Peggy Brooks, were residing in 

Snowden Hall, while he used our Distribution and Migration 

files to compile a list of former breeding sites of the peregrine 

falcon (Falco peregrinus) and then used the banding files for 

a paper on survival rates of banded birds. Peggy had been 

editing the bird population studies (Christmas counts, breeding 

bird census, and winter bird population studies) for the publication “Audubon Field Notes,” and she was very concerned 

that National Audubon Society would discontinue publishing 

the breeding and winter population studies when she resigned 

because they were not making a profit on them. John Aldrich, 

Bob Stewart, and I believed that these studies, especially the 

breeding bird censuses, which had been published since 1937, 

were important, so we agreed to serve on an editorial board 

with a few other scientists if the National Audubon Society 

would continue the publication.

I ended up editing the breeding bird censuses from 1952 

to 1966. The principal advantage to us of this collaboration was that it kept us in touch with serious bird population 

researchers throughout the United States and Canada, and 

these were the people I later recruited as State and Provincial 

coordinators when I launched the Breeding Bird Survey.

Collaboration with American Ornithologists’ 

Union

After Fred Lincoln retired, I was asked by Alexander 

Wetmore, Director of the Smithsonian Institution (Smithsonian), to update the range descriptions of the seabirds and 

shorebirds for the fifth (1957) edition of the AOU “Check-list 

of North American Birds.” I also became caretaker of the 

supply of back issues of the “Auk” (in the Nelson Laboratory 

attic), which had been Fred Lincoln’s duty as treasurer of the 

AOU. Back issues, as available, were distributed to U.S. and 

Canadian institutions; after that, the remainder was sent to 

the Smithsonian for their foreign exchange program. Another 

assignment was to compile the breeding and winter range 

descriptions and migration dates for the remaining volumes 

(warblers, blackbirds, finches, and sparrows) of A.C. Bent’s 

“Life Histories of North American Birds.”

Collaboration with other Conservation 

Organizations

I ran the Howard County mourning dove survey route 

for the Maryland Department of Natural Resources (DNR) 

from 1966 through 2008. I must admit that I would have been 

bored if I had recorded only the doves I heard and saw, so I 

recorded all species and reported only the doves to the DNR 

and the USFWS. The Howard County dove route had to be 

redrawn twice, first because of a permanent road closure and 

again because of traffic. The changes in route did not affect the 

dove counts, but did affect the counts of some of the songbird 

species. In 1982, I served on the DNR’s Monie Bay Estuarine 

Sanctuary Committee. I served on the Governor’s Executive 

Committee for Trees and Forests from 1992 to 1995, on the 

Regulations Review Team in 1991, and on the Belt Woods 

Advisory Committee during 1985–95.

I wrote the quarterly Season reports of bird observations 

for “Maryland Birdlife” from 1947 to 1977, and served as the 

MOS’s State president from 1952 to 1955, as editor of “Maryland Birdlife” from 1947 to 2014, and as an MOS trustee 

during 1961–2000. In 1968, biologist Willet T. Van Velzen 

and I published “Maryland Avifauna Number 2, The Field List 

of the Birds of Maryland” (44 pages), which shows updated 

migration and nesting dates.

I served as a trustee of the Bleitz Wildlife Foundation 

(1967–70) and Secretary of the International Bird Ringing 

Committee (1966–74), and was a member of the International 

Bird Census Committee (1966–87). Beginning with the International Ornithological Congress meeting at Oxford in 1966, 

I was the U.S. representative on the International Bird Census 

Committee (IBCC) and the European Ornithological Atlas 

Committee and also Secretary of the International Bird Ringing Committee. I participated in IBCC meetings at Oxford 

in 1966; Hilleröd, Denmark, in 1968; Ammarnäs in Swedish 

Lapland in 1969; Oosterbeek, Netherlands, in 1970; Warsaw 

in 1973; Szymbark, Poland, in 1976; Göttingen, Germany, in 

1979; Lyon, Spain, in 1981; Giles, Buckinghamshire, United 

Kingdom, in 1983; Dijon, France, in 1985; and Helsinki, 

Finland, in 1987. These meetings kept me in touch with all the 

latest international thinking and planning on bird census and 

atlas studies.

I wrote a chapter for Robert Shosteck’s 1968 “Potomac 

Trail Book,” and Bob Stewart and I wrote the Maryland/D.C. 

chapter for Sewall Pettingill’s 1951 “Guide to Bird Finding 

East of the Mississippi.” Patuxent’s Earl Baysinger and I were 

on the three-member USFWS team that drafted the United 
22 The History of Patuxent: America’s Wildlife Research Story

States/Soviet Union Migratory Bird Treaty using banding 

recoveries and the historic bird distribution and migration 

files. In 1976, we went to Moscow and Kiev to negotiate final 

details with our Soviet colleagues This treaty was unique in 

protecting not only the shared species, but also the habitats 

they required (https://www.fws.gov/le/pdf/MigBirdTreatyRussia.pdf, accessed December 17, 2015).

Cooperative Study of Hawk Migration

I had been intrigued by the regularity with which large 

numbers of migrating hawks were seen at Hawk Mountain, 

PA, and I thought there might be a more advantageous place 

than Monument Knob to intercept these flights in Maryland. 

Therefore, in the fall of 1949, I organized simultaneous counts 

at eight lookouts in the Catoctin/South Mountain range as well 

as a dozen along the more westerly ridges. I found that the 

raptor flight broke up into many minor flights along the low 

Maryland ridges, and then apparently became more organized 

along the higher Blue Ridge Mountains of Virginia. In the 

1950s, I encouraged hawk migration enthusiasts to participate 

in coordinated studies throughout the Appalachian Mountains, 

and, in 1974, I was one of the founders of the Hawk Migration 

Association of North America, which has now been monitoring raptor migration throughout the continent for nearly 

40 years.

The Albatross Problem on Midway Atoll

During World War II, the Navy took control of Midway 

Atoll (Midway) in the Hawaiian Leeward Chain as a base 

for Distant Early Warning (DEW) line flights from there to 

Adak in the Aleutian Islands. The nesting populations of 

Laysan albatrosses (Phoebastria immutabilis) and blackfooted albatrosses (Phoebastria nigripes) at Midway posed a 

serious problem because of the large size of these birds, their 

huge numbers (tens or even hundreds of thousands), and the 

Chan Robbins (right) and banding crew, Midway Atoll. Photo by U.S. Fish and 

Wildlife Service.

Laysan albatross Wisdom, alive and nesting in 2011, Midway Atoll. Photo by 

U.S. Fish and Wildlife Service.

fact that they showed no fear of man or aircraft. Attempts to 

frighten the birds or transport their young to other islands had 

failed. The USGS Laboratory in Denver sent Phil DuMont and 

Johnson Neff to Midway in 1954 to survey the situation, set up 

a study site near the station hospital, and band a small portion 

of the population. Dale Rice and Karl Kenyon spent a year 

there conducting life-history studies. John Aldrich and I went 

to Midway in December 1956 when the adults were establishing nesting territories, studied the birds on the hospital plot, 

and recaptured as many previously banded birds as we could.

I returned with an assistant for the next nine winters, 

conducting counts at various positions along the runways, trying different means of intimidation (none of which worked), 

and establishing study sites where nests were plotted to 1-ft 

accuracy on a permanent grid and adults and young were 

banded. On one such visit, I made an historic trip up the Leeward Chain with Gene Kridler, Win Banko, Ron Walker, and 

David Woodside on the buoy tender Blackhaw, stopping en 

route to survey the nesting birds on Nihoa and Necker, where 

few naturalists had ever landed. We also camped for a night in 

the Alakai Swamp, where I photographed an ‘o’u (Psittirostra 

psittacea), a bird now extinct (Scott and Kepler, 2016).

I returned in 1967 to recapture and reband as many birds 

as possible, in hopes that they would be recaptured again 

before the information on their aluminum bands became 

illegible or the bands fell off from corrosion. Hundreds of 

these birds were later recaptured by other investigators, who 

removed my bands and replaced them with theirs. Because the 

Bird Banding Laboratory keeps their records by band number 

instead of by bird, there is no forward continuity in the records 

and therefore still no way to determine how long the birds live.

On a brief trip to Midway in February 2002, I recaptured 

a Laysan albatross that was at least 50 years old: a female, 

named Wisdom, which was marked with a special band for 

easy recognition and was still alive and nesting in 2014. 

In the meantime, the Navy took two measures that we had 
The Early Years of Patuxent Research

Early Avian Studies at Patuxent 23

recommended to reduce the strike rate: they paved large strips 

along both sides of the runway to keep birds from nesting 

anywhere near flying aircraft, and they flattened the dunes 

from which the birds were using updrafts to fly across the 

runways. Midway is now a National Wildlife Refuge; the birds 

are protected.

Publications

Birds of Maryland and the District of Columbia

Bob Stewart and I expanded our field of investigation to 

include the entire State of Maryland. Frank Kirkwood’s 1895 

“A List of the Birds of Maryland” was long out of date and 

out of print. When Kirkwood died in 1945, W. Bryant Tyrrell 

rescued his big files of Maryland bird records and lent them 

to us. We contacted Maryland and Washington, D.C., bird 

observers, and set about gathering published and unpublished 

records from the first half of the 20th century. No existing 

State bird book contained breeding density information, but 

we believed it was important to document breeding densities in principal habitats throughout the State. Therefore, we 

prepared to do this, from marsh habitats on the Eastern Shore 

to apple orchards around Cumberland, to bogs, forests, and 

farmlands in Garrett County. Our book (Stewart and Robbins, 

1958) gives breeding densities for most breeding species, 

many derived from my Master’s thesis (Robbins, 1950) at 

George Washington University. It also includes distribution 

maps where appropriate, cites maximum counts, and shows 

where birds banded in Maryland have been reported.

Field Guide, Birds of North America

I am indebted to Patuxent Director Arnold Nelson for 

allowing me to take some time off in 1965 to work on Golden 

Press’s “Birds of North America” with Bertel Bruun and 

Herbert Zim (illustrated by Arthur Singer) (Robbins and others, 1966, 1983). I had initially refused to be involved with 

this field guide because I saw no need for it. Roger Peterson’s 

eastern and western bird guides were both excellent for use in 

the field, he and I were good friends, and I felt it was unfair to 

produce a competing volume. When Dr. Zim told me later that 

he was going to find another author and publish it anyway, I 

told him I would agree if Golden Press would make some concessions regarding layout. I wanted to make the Golden Press 

volume distinct from Peterson’s: birds would be shown against 

a background of their typical habitat; distribution maps, text, 

and illustrations would be on facing pages; and sonograms 

would be included, supplied from my personal collection of 

recordings. Golden Press resisted the sonogram idea, but I 

insisted that was not negotiable; there simply was not enough 

space to provide diagnostic verbal descriptions of bird songs 

and calls. I also parted with tradition by using actual live 

measurements of hand-held birds in natural positions rather 

than the published lengths of stretched-out museum skins. Few 

people have noticed the accent marks showing how to pronounce the Latin names and the typical number of songs per 

minute—which can be helpful to folks who are tone deaf (for 

example, 2–4 per minute [/min] for Acadian flycatcher [Empidonax virescens], 6–11/min for eastern wood-pewee [Contopus virens], 20–40/min for eastern phoebe [Sayornis phoebe], 

and 50–70/min for least flycatcher [Empidonax minimus]).

Birds in Our Lives

Nine Patuxent staff members were among the 61 authors 

who contributed to the impressive “Birds in Our Lives” 

volume edited by Alfred Stefferud and Arnold Nelson and 

published by the Bureau of Sport Fisheries and Wildlife in 

1966 (Stefferud and Nelson, 1966). Notable was a chapter by 

Patuxent chief veterinarian Carlton Herman about the interesting way that studies of birds were improving our knowledge 

of human health issues, a chapter by Chief of the Bird Banding Laboratory Allen Duvall on bird migration, and a chapter 

by former Patuxent director John Buckley on how to avoid 

problems with birds. Two chapters written by me included one 

on the Christmas Bird Count and one on exotic bird species 

introductions, which I coauthored with Gardiner Bump.

Special Scientific Reports—Wildlife

The chief official outlet for progress reports in wildlife 

studies was the USFWS Special Scientific Report series. The 

first in this series (Aldrich and others, 1949) was a compilation of maps of banding recoveries of waterfowl, largely by 

Patuxent staff members. Status reports on waterfowl, doves, 

woodcock, snipe and rails, albatrosses, and the Breeding Bird 

Survey were among the early issues.

References Cited

Aldrich, J.W., Hawkins, A.S., Addy, C.E., Jensen, G.H., Smith, 

A.G., Low, S.H., Stoudt, J.H., Robbins, C.S., Duvall, A.J., 

and Stewart, R.E., 1949, Migration of some North American 

waterfowl—A progress report on an analysis of banding 

records: Washington, D.C., U.S. Fish and Wildlife Service, 

Special Scientific Report—Wildlife, no. 1, 48 p. [Also available at https://archive.org/details/migrationofsomen00aldr.]

Aldrich, J.W., Lynch, John, Goodrum, Phil, Reid, V.H., Solman, V.E.F., Mendall, H.L., English, P.F., Stewart, R.E., 

Sheldon, W.G., Wright, Bruce, Robbins, C.S., and Burleigh, 

T.D., 1952, Investigations of woodcock, snipe, and rails in 

1951: Washington, D.C., U.S. Fish and Wildlife Service, 

Special Scientific Report—Wildlife, no. 14, 58 p.
24 The History of Patuxent: America’s Wildlife Research Story

Baird, James, Robbins, C.S., Bagg, A.M., and Dennis, J.V., 

1958, “Operation Recovery”—The Atlantic coastal netting 

project: Bird-Banding, v. 29, no. 3, p. 137–168. [Also available at http://sora.unm.edu/node/49575.]

Briggs, S.A., and Criswell, J.H., 1979, Gradual silencing of 

spring in Washington—Selective reduction of species of 

birds found in three woodland areas over the past 30 years: 

Atlantic Naturalist, v. 32, p. 19–26.

Clifford, C.M., Sonenshine, D.E., Atwood, E.L., Robbins, 

C.S., and Hughes, L.E., 1969, Tests on ticks from wild 

birds collected in the eastern United States for rickettsiae 

and viruses: American Journal of Tropical Medicine and 

Hygiene, v. 18, no. 6, p. 1057–1061. [Also available at 

http://www.ajtmh.org/content/18/6/1057.extract.]

Houston, C.S., Robbins, C.S., and Klimkiewicz, M.K., 2008, 

History of “computerization” of bird-banding records: 

North American Bird Bander, v. 33, no. 2, p. 53–65. 

[Also available at https://sora.unm.edu/sites/default/files/

nabb_33-2_53-65v2.pdf.]

Ingraham, S.E., 1938, Instinctive music: Auk, v. 55, no. 4, 

p. 614–628. [Also available at https://sora.unm.edu/

node/17686.]

Lowery, G.H., Jr., and Newman, R.J., 1955, Direct studies of 

nocturnal bird migration, in Wolfson, Albert, and Davis, 

D.E., eds., Recent studies in avian biology: Champaign, IL, 

University of Illinois Press, p. 238–263.

Mitchell, R.T., Blagbrough, H.P., and VanEtten, R.C., 

1953, The effects of DDT upon the survival and growth 

of nestling songbirds: Journal Wildlife Management, 

v. 17, no. 1, p. 45–54. [Also available at http://dx.doi.

org/10.2307/3796804.]

Robbins, C.S., 1950, Ecological distribution of the breeding 

Parulidae of Maryland: George Washington University, 

unpublished M.A. thesis, 145 p.

Robbins, C.S., 1964, A guide to the aging and sexing of wood 

warblers (Parulidae) in fall: Eastern Bird Banding Association News, v. 27, no. 5, p. 199–215.

Robbins, C.S., 1977, Data bank of North American breeding bird censuses: Polish Ecological Studies, v. 3, no. 4, 

p. 95–98.

Robbins, C.S., and Stewart, R.E., 1949, Effects of DDT on 

bird population of scrub forest: Journal of Wildlife Management, v. 13, no. 1, p. 11–16. [Also available at http://dx.doi.

org/10.2307/3796121.]

Robbins, C.S., Bruun, Bertel, and Zim, H.S., 1966, Birds of 

North America—A guide to field identification: Racine, WI, 

Golden Press, Western Publishing Company, Inc., 360 p. 

[Revised 1983.]

Robbins, C.S., Springer, P.F., and Webster, C.G., 1951, Effects 

of five-year DDT application on breeding bird population: 

Journal of Wildlife Management, v. 15, no. 2, p. 213–216. 

[Also available at http://dx.doi.org/10.2307/3796613.]

Robbins, C.S., Bridge, D., and Feller, R., 1959, Relative 

abundance of adult male redstarts at an inland and a coastal 

locality during fall migration: Maryland Birdlife, v. 15, 

no. 1, p. 23–25.

Scott, J.M., and Kepler, C.B., 2016, Endangered species 

research in Hawaii—The early years (1965–87), in Perry, 

M.C., ed., The history of Patuxent—America’s wildlife 

research story: U.S. Geological Survey Circular 1422, 

p. 183–196. [Also available at https://doi.org/10.3133/

cir1422.]

Short, L.L., Jr., and Robbins, C.S., 1967, An intergeneric hybrid wood warbler (Seiurus x Dendroica): Auk, 

v. 84, no. 4, p. 534–543. [Also available at http://dx.doi.

org/10.2307/4083334.]

Stamm, D.D., Davis, D.E., and Robbins, C.S., 1960, A method 

of studying wild bird populations by mist-netting and banding: Bird-Banding, v. 31, no. 3, p. 115–130. [Also available 

at http://sora.unm.edu/node/49650.]

Stefferud, Alfred, and Nelson, A.L., eds., 1966, Birds in our 

lives: Washington, D.C., U.S. Fish and Wildlife Service, 

561 p.

Stewart, R.E., 1952, Clapper rail studies, 1951, in Aldrich, 

J.W., Lynch, John, Goodrum, Phil, Reid, V.H., Solman, 

V.E.F., Mendall, H.L., English, P.F., Stewart, R.E., Sheldon, W.G., Wright, Bruce, Robbins, C.S., and Burleigh, 

T.D., Investigations of woodcock, snipe, and rails in 1951: 

Washington, D.C., U.S. Fish and Wildlife Service, Special 

Scientific Report—Wildlife, no. 14, p. 56–58.

Stewart, R.E., and Robbins, C.S., 1958, Birds of Maryland 

and the District of Columbia: Washington, D.C., U.S. Fish 

and Wildlife Service, North American Fauna No. 62, 401 p. 

[Also available at http://www.fwspubs.org/toc/nafa//62.]

Stewart, R.E., Cope, J.B., Robbins, C.S., and Brainerd, J.W., 

1952, Seasonal distribution of bird populations at the 

Patuxent Research Refuge: American Midland Naturalist, 

v. 47, no. 2, p. 257–363. [Also available at http://dx.doi.

org/10.2307/2422265.]

Williams, A.B., 1936, The composition and dynamics of a 

beech-maple climax community: Ecological Monographs, 

v. 6, no. 3, p. 318–408. [Also available at http://www.jstor.

org/stable/1943219.]
The Early Years of Patuxent Research

Early Population And Contaminant Studies At Patuxent

By Russell J. Hall

I was asked to write on the topic “Early population and 

contaminant studies.” By way of disclosure, I have to confess that I have no direct knowledge of this topic. I arrived 

at Patuxent Wildlife Research Center (Patuxent) in 1977, 

long after its major programs were well developed, so the 

information I provide here is secondhand. Of course, with 

the rare exception of research biologist Chan Robbins, who 

started work at Patuxent in 1946, few people still living have 

direct experience of those times. I was fortunate, however, to 

develop a close relationship with several other scientists who 

worked at Patuxent in the 1940s.

Much of my knowledge about Patuxent’s programs in 

the 1930–40s was learned from random conversations with 

Lucille and William Stickel, who were fellow researchers 

during my tenure at Patuxent. In addition, I was privileged to 

have the opportunity to discuss the topic with Lucille a few 

months before her death in 2007. The remainder of what I 

know is derived from various written records—mostly scientific literature. While at Patuxent, I had two assignments that 

required me to summarize this information, and much of the 

discussion that follows is based on that past work (Hall, 1987, 

1988). The written records are more objective, but perhaps 

less insightful, than the anecdotal information.

As you will read in other chapters in this volume, Patuxent was established in 1936 as a “research refuge.” The term 

“habitat restoration” has been used (Perry, 2004), but I think 

there is more. Some understanding of Patuxent’s purpose 

may be achieved by considering what was happening at that 

time in our Nation’s history. Think of the Dust Bowl and the 

Great Depression, and keep in mind that many more people 

and much more of the landscape were involved in agriculture 

then than at any time since. The population was increasing, 

and it was expected that agricultural production would also 

need to increase. Agriculture already dominated much of the 

Nation’s landscape and, by today’s standards, was inefficient, 

wasteful, and destructive to the environment. Unless some 

major change occurred, America’s wildlife would be subject to 

increasing pressure.

In response to the plethora of ongoing and impending 

problems, the U.S. Department of Agriculture (USDA) was 

gaining in size and influence, and was promoting scientific 

farming. Some of its units were working on the productivity 

side of the equation, whereas its Soil Conservation Service 

was engaged in applying the benefits of science to the urgent 

Dr. Durward Allen inspecting bicolor lespedeza (Lespedeza bicolor) at 

Patuxent Research Refuge, Laurel, MD, 1949. Photo by Francis M. Uhler, 

Patuxent Research Refuge.

task of curtailing the wholesale wastage of natural resources 

that was then underway. The Bureau of Biological Survey was 

also deeply involved in conservation, because it was a unit of 

the USDA at the time of Patuxent’s founding. Patuxent was 

not transferred to the Department of the Interior until 1940 and 

was developed in concert with the adjoining Beltsville Agricultural Research Center (Beltsville, MD), so it is not surprising that Patuxent’s connection with agriculture was important 

from the beginning. Therefore, many of Patuxent’s underpinnings and much of its initial focus were agriculture-related.

One early program at Patuxent was a formal Farm 

Wildlife program. Two farms were operated on site, one of 

which was designed by the Soil Conservation Service to study 

enlightened farming practices that included many measures 

to promote wildlife. A comparable farm was designed and 

operated using the practices that were typical of the time. The 

scientists’ task was to evaluate the results of the enlightened 

kind of farming. Many scientists believe that the program was 

never fully successful, mainly because of the long time needed 

for plants to grow and develop good wildlife habitat. One 

product of the studies was the booklet “The Farmer and Wildlife” by Dr. Durward Allen (Allen, 1949), based on his work 

at Patuxent. This document was published by the Wildlife 

Management Institute, Washington, D.C., and reprinted many 

times in response to requests by farmers.
26 The History of Patuxent: America’s Wildlife Research Story

Harvesting hay at Patuxent Research Refuge, Laurel, MD, 1952. Photo by 

Francis M. Uhler, Patuxent Research Refuge.

Unfortunately, however, no statistically reliable data on 

wildlife productivity were obtained, none of the anticipated 

impressive results materialized, and the program became an 

easy target for budget cutters. Reductions in force resulted 

in the termination of nearly all employees in the program. 

Some of the few who remained were able to grasp the 

emerging threats to wildlife posed by the new pesticides 

that were just becoming available, and their insights led to 

the development of what was to become the Environmental 

Contaminant Program.

Although the expression had not yet been coined at the 

time, the introduction of synthetic pesticides after the Second 

World War was one of the harbingers of what would later 

be called “the Green Revolution.” These pesticides vastly 

increased agricultural productivity, permitting a reduction in 

the number of acres in cultivation, resulting in abandonment 

of farmlands that could later regenerate into wild lands, and 

ultimately contributing to wholesale population shifts from the 

countryside to urban areas. Only a few people appreciated the 

potential adverse side effects of pesticide use on wildlife at the 

time; fortunately, a small number of them were at Patuxent. 

With funding from the USDA, Patuxent became involved in 

a suite of studies of the new chemicals that were underway in 

many venues.

Think about the importance of this development for 

a moment, and consider why it was so fortunate that it all 

began at Patuxent instead of somewhere else. Patuxent had 

the already mentioned connection with farming practices 

that was fostered by the early connections with the USDA 

and the ill-fated Farm Wildlife program. Land was available 

for outdoor experiments in realistic surroundings. Facilities 

were, or would be in the future, available for maintaining and 

propagating wildlife in captivity, making large-scale, statistically valid experimental studies possible. A chemistry laboratory was present that was originally established for work on 

wildlife nutrition, but ultimately its emphasis could be shifted 

to chemical toxicology. Wildlife disease specialists who could 

diagnose pathologies and animal control specialists who were 

looking for ways to control nuisance wildlife, often with toxins, were available. The connection with wildlife population 

studies was also strong; methods for determining pesticide 

effects on populations in the field were needed, and Patuxent scientists, who were pioneering methods for estimating 

the abundance of bird and small mammal populations, could 

(and did) use their expertise to assess the results of pesticide 

applications. Any specialized expertise that was not available 

in-house could be obtained from the adjacent Beltsville Agricultural Research Center.

DDT was patented in 1940 and brought to market in 

1942. It was immediately hailed as a great boon to humankind, 

and Paul Müller, discoverer of its insecticidal properties, was 

awarded the Nobel Prize in Physiology and Medicine in 1948. 

The first studies of DDT by Patuxent scientists were conducted 

in 1943, and the first papers were published in 1946, just after 

the end of the Second World War.

These original studies burst on the scene together in 

volume 10 of The Journal of Wildlife Management in 1946. 

They are—

• R.T. Mitchell—Effects of DDT spray on eggs and 

nestlings of birds;

• R.E. Stewart and others—Effects of DDT on birds at 

the Patuxent Research Refuge;

• N. Hotchkiss and R.H. Pough—Effects on forest birds 

of DDT used for gypsy moth control in Pennsylvania;

• D.R. Coburn and R. Treichler—Experiments on toxicity of DDT to wildlife; and

• L.F. Stickel—Field studies of a Peromyscus population 

in an area treated with DDT.

See the “References Cited” section below for the complete 

citations.

Some of the authors of these original studies were field 

ornithologists, but Hotchkiss was a wetland ecologist, Coburn 

was a disease specialist, and Stickel’s ongoing research was on 

population ecology, emphasizing small mammals and reptiles.

Despite the apparent thoroughness of these very early 

studies, they failed to elucidate the true hazard to wildlife 

posed by DDT. For the most part, they demonstrated that 

DDT applications were relatively safe to wildlife when used 

judiciously and when application levels were conservative. 

Another 20 years and development of entirely new research 

methodologies would be required before the researchers 

were able to understand the effects of the chemical on bird 

reproduction and the mechanisms responsible for them. 

Studies of DDT continued through the 1950s, as did research 

on other synthetic pesticides, some with much more direct 

lethal effects.

Until passage in 1958 of the Magnuson-Metcalf Bill 

(Magnuson-Metcalf), which required testing of pesticides, 

the USDA funded most studies of pesticides at Patuxent. This 

outside funding was instrumental in keeping other research at 
The Early Years of Patuxent Research

Early Population And Contaminant Studies At Patuxent 27

Patuxent afloat during lean times. Magnuson-Metcalf required 

acute and chronic studies of 200 pesticides on fish and wildlife 

species. Lists of publications from this period reveal that most 

Patuxent scientists were involved in one or more pesticide 

studies in addition to their permanent assignments. Passage 

of Magnuson-Metcalf permitted the recruitment of permanent 

staff for the research, and of course funding increased dramatically after the publication of “Silent Spring” by Rachel 

Carson (1962).

The Federal Environmental Pesticides Control Act 

(FEPCA) of 1972 amended the Federal Insecticide, Fungicide, and Rodenticide Act of 1947 to require manufacturers 

of new pesticides to perform a variety of tests to prove that 

the pesticide did not have “unreasonable adverse effects” on 

human health or the environment. Wildlife toxicity studies at 

Patuxent played a critical role in helping to enact FEPCA. In 

turn, once enacted, the statute helped provide further initiative 

and support for the development of additional avian toxicity 

tests at Patuxent.

As I noted in my book “Patuxent, Policy, and the Public Interest” (Hall, 2008), wildlife toxicology became a new 

career for me and for many others. It is now a recognized 

scientific field practiced by legions of investigators in many 

parts of the world. To the lists of “firsts” marking the history 

of Patuxent cited in this volume should be added that Patuxent 

was the birthplace of the wildlife toxicology discipline in the 

United States.

References Cited

Allen, D.A., 1949, The farmer and wildlife: Washington, D.C., Wildlife Management Institute, 84 p. 

[Also available at https://babel.hathitrust.org/cgi/

pt?id=mdp.39015006126976.]

Carson, R.L., 1962, Silent spring: Boston, MA, Houghton 

Mifflin, 368 p.

Coburn, D.R., and Treichler, Ray, 1946, Experiments on toxicity of DDT to wildlife: Journal of Wildlife Management, 

v. 10, no. 3, p. 208–216. [Also available at http://dx.doi.

org/10.2307/3795834.]

Hall, R.J., 1987, Impact of pesticides on bird populations, 

in Marco, G.J., Hollingworth, R.M., and Durham, W., eds., 

Silent spring revisited: Washington, D.C., The American 

Chemical Society, chap. 6, p. 85–111.

Hall, R.J., 1988, An annotated bibliography of field studies conducted on the Patuxent Wildlife Research Center—1940–1987: U.S. Fish and Wildlife Service Biological 

Report, v. 88, no. 2, 16 p. [Also available at https://babel.

hathitrust.org/cgi/pt?id=uiug.30112106918979.]

Hall, R.J., 2008, Patuxent, policy, and the public interest—

Reflections on a career in government science: Gainesville, 

FL, Lighthall Books, 253 p.

Hotchkiss, Neil, and Pough, R.H., 1946, Effects on forest birds 

of DDT used for gypsy moth control in Pennsylvania: Journal of Wildlife Management, v. 10, no. 3, p. 202–207. [Also 

available at http://dx.doi.org/10.2307/3795833.]

Mitchell, R.T., 1946, Effects of DDT spray on eggs and 

nestlings of birds: Journal of Wildlife Management, v. 10, 

no. 3, p. 192–194. [Also available at http://www.jstor.org/

stable/3795831.]

Perry, M.C., 2004, The evolution of Patuxent as a research 

refuge and a wildlife research center: Laurel, MD, U.S. 

Geological Survey Patuxent Wildlife Research Center, 

20 p., accessed October 3, 2011, at http://www.pwrc.usgs.

gov/history/cronhist/patuxenthistory_perry.pdf.

Stewart, R.E., Cope, J.B., Robbins, C.S., and Brainerd, 

J.W., 1946, Effects of DDT on birds at the Patuxent 

Research Refuge: Journal of Wildlife Management, 

v. 10, no. 3, p. 195–201. [Also available at http://dx.doi.

org/10.2307/3795832.]

Stickel, L.F., 1946, Field studies of a Peromyscus population 

in an area treated with DDT: Journal of Wildlife Management, v. 10, no. 3, p. 216–218. [Also available at http://

dx.doi.org/10.2307/3795835.]
28 The History of Patuxent: America’s Wildlife Research Story

Dusky seaside sparrow tagged at Merritt Island, National Wildlife Refuge, FL, 1970. 

Photo by Paul Sykes, U.S. Fish and Wildlife Service.
Migratory Bird Research, Monitoring, and Management

Migratory Bird Program at the U.S. Geological Survey 

Patuxent Wildlife Research Center/U.S. Fish and Wildlife 

Service Patuxent Research Refuge: Transformations in 

Management and Research

By R. Michael Erwin and Robert J. Blohm

Introduction

The Patuxent Wildlife Research Center (Patuxent), first 

known as the Patuxent Research Refuge, has a long and rich 

history of participation in the Department of Interior’s (DOI) 

cooperative efforts to protect and conserve migratory birds in 

North America. This chapter describes many of the events and 

the people involved that constitute this important timeline for 

international conservation of a shared wildlife resource.

The Patuxent Research Refuge, renowned worldwide, 

is part of the National Wildlife Refuge System of the U.S. 

Fish and Wildlife Service (USFWS) that has, at different 

times and under a variety of organizational iterations, provided the physical location of Patuxent, the Migratory Bird 

Population Station (MBPS), the Migratory Bird and Habitat 

Research Laboratory (MBHRL), and the Laurel Branch of the 

Office of Migratory Bird Management (MBMO, now Division of Migratory Bird Management [DMBM]). This chapter 

also emphasizes the interrelations between the management 

objectives of the USFWS and the research program at Patuxent. Following incorporation of the research program into the 

National Biological Survey (NBS) and subsequently into the 

U.S. Geological Survey (USGS), the Migratory Bird program took on new identities, while the management functions 

continued to evolve within the USFWS despite these changes. 

Nevertheless, the USFWS and other agencies such as the 

National Park Service (NPS) were longstanding “clients” of 

the research community within DOI, and many of the former 

linkages between management and research were maintained.

Origins of the Migratory Bird Program

The Federal Migratory Bird Treaty Act of 1918, following earlier bird protection laws such as the Lacey Act (1900) 

and the Migratory Bird Act (1913), was one of the earliest 

and arguably one of the most important environmental laws 

enacted in the United States. These laws followed early efforts 

of protection initiated by the National Audubon Society and 

other organizations that recognized the devastating effect 

of unregulated sport and plume hunting on many species 

of migratory birds. As a result, more than 800 species of 

birds now receive protection under the act, which remains a 

landmark of wildlife conservation legislation, protecting our 

continent’s migratory bird resource.

Most of the management and research on birds that 

occurred in the United States after the Federal Migratory 

Bird Treaty Act was passed, however, was directed at the 

agricultural impacts of birds. In fact, at the time of enactment, 

Federal responsibilities for migratory birds were assigned to 

the U.S. Department of Agriculture (USDA), Bureau of Biological Survey. Depredations on crops by blackbirds, starlings 

(Sturnus vulgaris), sparrows, crows (Corvus brachyrhychos), 

and other species dictated much of the focus of bird research 

in the USDA. Ironically, rather than concentrating on conservation, the early decades were devoted mainly to controlling 

bird populations! During the 1930s, the Dust Bowl drought 

period in the interior of the country, combined with excessive 

hunting, severely depleted waterfowl populations, forcing some changes in Federal responsibilities. In 1940, bird 

research, along with the Bureau of Biological Survey, was 

transferred from the USDA to the DOI, under the USFWS. 

A major division within the new agency was the Federal 

Wildlife Refuge System. Several Federal refuges had already 

been designated (beginning with Pelican Island in Florida, 

designated by President Theodore Roosevelt in 1903), 

focusing primarily on providing quality habitat along waterfowl migration routes and at wintering areas. The Patuxent 

Research Refuge (the original name of Patuxent as established 

in 1936) was unique in being the only refuge created with 

the term “research” in its enabling legislation. As part of its 

research mission, the Federal banding program, begun in 1920 

in Washington, D.C., was transferred to the Patuxent Research 

Refuge in 1942, where it evolved into the Bird Banding 

Laboratory. For more information about the early history of 

Patuxent, visit the Web site http://www.pwrc.usgs.gov/75th/

pwrc_timeline_20110830/ and other chapters in this report.
30 The History of Patuxent: America’s Wildlife Research Story

The Early Years at Patuxent: 1936–70

Much of the work conducted at Patuxent from the 1930s 

through the 1960s was centered on basic waterfowl biology 

and a variety of agricultural questions. Experimental work on 

various seeds of aquatic plants collected across North America 

was started by research biologist Francis Uhler on the Patuxent impoundments. His primary motivation was to determine 

which species were best propagated in impounded fresh and 

brackish water to enhance overwintering waterfowl populations. Whereas today’s ecologists consider invasive species 

to be a recent phenomenon in the United States, Patuxent 

biologists were working on the problem in the early 1950s; 

invasive plants and their effects on habitat conditions became 

focal areas of research on freshwater wetlands and in Chesapeake Bay. Water chestnut (Trapa natans) (Uhler, 1954) and 

Eurasian watermilfoil (Myriophyllum spicatum) (Steenis 

and Stotts, 1965) were two of the important invaders that 

prompted efforts to develop effective control measures. Much 

of this early natural history work at the refuge was based 

on individual knowledge of aquatic plant life histories, and 

many experiments were conducted both in greenhouses and 

in impoundments, albeit not in a rigorous hypothesis-testing 

framework. Mr. Uhler, John Steenis, and Neil Hotchkiss were 

some of the early Patuxent biologists who brought years of 

field experience to the refuge programs.

Studies of the population dynamics of waterfowl began 

very early at Patuxent under the auspices of the USFWS, Division of Wildlife Research, with coordinated banding programs 

begun in earnest in the 1950s (Hawkins and others, 1984). As 

mentioned earlier, national concerns for waterfowl population 

declines were voiced following the Dust Bowl-era droughts of 

the 1930s in much of the continent’s interior, and later following periods of little precipitation and reduced duck numbers 

in the late 1940s. Banding crews were assigned to Montana, 

the Dakotas, and three western Canadian provinces to band 

flightless mallards (Anas platyrhynchos), as well as other 

ducks captured coincidentally with mallards, while adults 

were molting. The emphasis at this time was to determine the 

distribution of the mallard harvest. Other early efforts included 

diving duck banding in Alaska and black duck (Anas rubripes)

banding in the Maritimes of Canada.

Biologists at Patuxent also figured prominently in early 

cooperative efforts to establish better ways of monitoring 

the status of waterfowl. Following World War II, the lack of 

breeding ground information on declining waterfowl populations prompted biologists and administrators in Canada and 

the U.S. to explore ways of developing improved methods of 

counting these birds and evaluating their breeding habitats 

across large areas of the continent in the spring. Fortunately, 

after the war, small aircraft were available as surplus and 

soon became part of the fleet used in experimental survey 

work of wildlife populations, namely waterfowl. Work in the 

air and on the ground revealed that birds could be counted 

by species from low-flying aircraft, and soon a statistically 

reliable method for determining breeding population size and 

Art Hawkins nest searching, Minnedosa, Manitoba, 

Canada, 1978. Photo by Matthew C. Perry, U.S. Fish and 

Wildlife Service.

distribution of waterfowl and assessing habitat conditions was 

in place. This annual survey, first operational in 1955, was 

then expanded beyond its origins in the prairie-parkland region 

of western Canada and the north-central U.S. to northern 

“bush” areas, including parts of Alaska. In the early 1960s, a 

second annual (July) survey was established to obtain a measure of waterfowl productivity by counting broods.

This cooperative effort to count waterfowl each year on 

the breeding grounds is widely recognized as one of the most 

reliable wildlife surveys in the world. Moreover, it remains a 

primary source of information used in the annual development 

of hunting regulations in Canada and the U.S. Biologists from 

Patuxent, who played key roles in this survey achievement, 

included Walter Crissey (see Crissey’s autobiography [Crissey, 

2006]), E.B. (Jake) Chamberlain, Fred Glover (see Glover, 

2010), Chuck Evans, and John (Johnny) Lynch. During this 

period, many biologists, including flyway biologists (pilots), 

were associated with migratory game-bird management 

investigations and assigned to management offices within the 

USFWS (for example, Branch of Game Management, later 

Branch/Division of Management and Enforcement).

Because of their field responsibilities, biologists were 

typically often stationed around the country, including at 

Patuxent (Chamberlain, Glover, and Evans). Crissey, a biologist for migratory game birds in the Section of Waterfowl 

Management Investigations, Division of Wildlife Research, 

and stationed at Patuxent, was also a pilot (and later became 

the first director of MBPS; see below). Lynch, who was 
Migratory Bird Research, Monitoring, and Management

Migratory Bird Program: Transformations in Management and Research 31

stationed in coastal Louisiana for virtually his entire career, 

operated a field office for Patuxent and was actively involved 

with surveys of snow geese (Anser caerulescens) and other 

Gulf Coast waterfowl. Chamberlain, Glover, and Evans 

were instrumental in evaluating the feasibility (later deemed 

impractical until renewed efforts in the 1980s) of establishing 

systematic waterfowl surveys in eastern Canada to complement efforts in the West. Over the years, Dr. Glover also 

participated extensively in the Canadian waterfowl banding 

program, as well as winter surveys in Mexico and Central 

and South America. Dr. Joe Linduska, editor of “Waterfowl 

Tomorrow” (Linduska, 1964), which chronicled at the time 

more than three decades of work on waterfowl in North America, including the aforementioned survey and banding efforts, 

was also a colleague of Crissey, Glover, and others at Patuxent in the early 1950s; he later became Chief of the Branch of 

Game Management in the USFWS.

Crissey also worked with Patuxent biologist Earl Atwood 

in the early 1950s to design and implement a national mail 

survey that would provide annual estimates of the number of 

waterfowl hunters and their harvest of ducks and geese. This 

approach far surpassed earlier efforts to estimate waterfowl 

harvest that relied on hunter bag checks, which were of little 

meaningful use in managing the annual kill. A few years later, 

Dr. Aelred Geis and Mr. Samuel Carney, both stationed at 

Patuxent, developed the Waterfowl Parts Collection Survey 

that is still conducted annually to estimate the species, sex, 

and age composition of the duck and goose harvest in the U.S. 

Among others working in the harvest surveys group at the 

time were Glen Smart, Ed Rosasco, and Woody Martin.

More locally, with the proximity of Chesapeake Bay to 

Patuxent, a good deal of waterfowl research took place in 

the bay, with interest in both native tundra swans (Cygnus 

columbianus) (formerly whistling swans) and non-native mute 

swans (Cygnus olor), as well as the large wintering populations of canvasbacks (Aythya valisineria). These nearby wildlife resources fostered a long line of research and management 

work by staff centered at Patuxent that continues in various 

forms today.

It soon became apparent that with the successful development and implementation of several large-scale data-gathering 

efforts for migratory birds, and with other monitoring efforts 

Leaders in Migratory Birds at Patuxent Wildlife Research Center meeting, Laurel, MD, 1969. (Left to right: 1st row, Frank 

Bellrose, Ian Nisbet, Ira Gabrielson, Walter Crissey, Roland Clement; 2nd row, Oliver Austin, William Drury, Robert Carrick, 

Eugene Dustman; 3rd row, Howard Wight, John Aldrich, Charles Henny, Kenneth Williamson, Hugh Boyd; 4th row, Lars 

von Haartman, Laurence Jahn, Joseph Hickey, Harvey Nelson; 5th row, Lee Eberhardt, Aelred Geis, John Gottschalk, 

Alexander Dzubin.) (From U.S. Fish and Wildlife Service, 1972)
32 The History of Patuxent: America’s Wildlife Research Story

under consideration, the ever-growing base of information that 

resulted was quickly outstripping annual efforts for analysis and interpretation. Consequently, in 1961, the USFWS 

reorganized within the Division of Research by creating the 

Migratory Bird Populations Station located at Patuxent. This 

new but separate office was given specific responsibilities that 

combined both research and management functions, whereas 

other ongoing research activities, such as environmental 

contaminants, animal damage control, and wetland ecology, 

remained with the research facility. Special emphasis was 

given to the analysis and interpretation of the aforementioned 

large stores of information on migratory birds that were 

becoming available each year, in addition to other biological 

investigations that were assigned to the station. The internationally recognized Bird Banding Laboratory (BBL) became 

part of this new organization as well, and many band-recovery 

data, critical in the development of annual hunting regulations, 

added to the workload.

Walt Crissey was appointed the first director of MBPS. 

Other migratory bird biologists in this office included Al Geis, 

John P. Rogers (assistant director, following Al Geis); Chan 

Robbins (Non-Game Birds); Howard Wight, Bill Kiel, Jim 

Teer, Fant Martin, Roy Tomlinson, Jim Ruos, Bill Goudy, 

and Milt Reeves (Migratory Shore and Upland Game Birds); 

Al Duvall and Earl Baysinger (Bird Banding Laboratory); 

and Robert I. Smith, Kahler Martinson, Chuck Kaczynski 

(Kimball), Cal Lensick, Chuck Henny, Dave Anderson, Ken 

Burnham, and Dick Pospahala (Waterfowl).

Whereas ducks, geese, and swans were the primary focus 

at the outset, other migratory game-bird species, including 

woodcock (Scolopax minor), mourning doves (Zenaida macroura), white-winged doves (Zenaida asiatica), and rails, soon 

received much-needed attention from staff at the station. Work 

focused on many aspects of the annual cycle of these webless 

game-bird species, with particular emphasis on population status, productivity, habitat requirements, and mortality factors, 

including hunting (see Sanderson, 1977). Important advances 

were soon forthcoming. Ongoing analyses of band-recovery 

information helped inform the creation of two management 

units for woodcock in the eastern and central U.S. Biologists, 

including Fant Martin, Bill Goudy, and later Bill Krohn, Tom 

Dwyer, and others, helped establish and refine the woodcock 

singing ground survey, contributed to the development of valid 

sex and age identification criteria for harvested woodcock 

(using their wings [F. Martin]), and improved understanding of woodcock biology and management. Mourning dove 

work also benefited from staff work at Patuxent. For example, 

the three management units that guide the activities of dove 

managers today are based on an analysis of mourning dove 

band recoveries by Bill Kiel in the late 1950s, and Patuxent 

and MBPS staff helped improve the long-running call-count 

survey, using a stratified random sampling approach for the 

selection of survey routes around the country, during 1957–66. 

An outgrowth of Roy Tomlinson’s work while at the station in 

the mid-1960s was the development of a comprehensive, longrange research and management program for mourning doves 

in the U.S. (R.E. Tomlinson, 1966, unpub. report available 

at the U.S. Fish and Wildlife Service, Division of Migratory 

Bird Management).

Parallel to the migratory game-bird work, the Animal 

Damage Control unit was formed at Patuxent, following the 

transfer of the “economic pests” programs from the USDA to 

DOI in 1940. The early emphasis at Patuxent was on research 

to evaluate how hedgerow and field border management for 

wildlife might minimize effects on agricultural production. 

One of the more productive researchers, Brooke Meanley, 

conducted many studies of red-winged blackbirds (Agelaius 

phoeniceus) in grain-belt areas, where the emphasis was on 

finding control solutions at the huge wintering roosts. His 

interests included rails and other marsh species in addition to 

blackbirds (Meanley and Webb, 1963; Meanley, 1975).

A major change in wildlife and avian science occurred 

after the 1962 publication of Rachel Carson’s “Silent Spring” 

(Carson, 1962). This award-winning book has been widely 

recognized by environmental scientists across North America 

as the most influential book on the environment published in 

the 20th century. It spurred national concerns for both wildlife 

and human health. As a result, a major new research thrust was 

undertaken at Patuxent with the formation of a Contaminants 

Research program—first under Dr. Eugene Dustman, followed 

by Dr. Lucille Stickel—that was separate from the Migratory 

Bird program. This new focus provided a major impetus to the 

“nongame-bird” research field that had been quietly progressing under Robert Stewart and Chandler Robbins since the late 

1940s. In spite of very limited funding, these two biologists 

produced a much-cited book on bird distribution throughout 

the Washington, D.C., and Chesapeake Bay area (Stewart and 

Robbins, 1958).

Robbins, concerned with songbird declines reported by 

many citizens, teamed up with Canadian Wildlife Service 

Brooke Meanley banding blackbirds at night in Arkansas, 1951. Photo by 

Garner Allen, U.S. Fish and Wildlife Service volunteer.
Migratory Bird Research, Monitoring, and Management

Migratory Bird Program: Transformations in Management and Research 33

Bob Stewart raking submerged aquatic vegetation in the Susquehanna Flats, 

Chesapeake Bay, 1950s. Photo by Paul F. Springer, U.S. Fish and Wildlife 

Service.

biologist Anthony Erskine to create the North American 

Breeding Bird Survey (BBS), using volunteers across the 

U.S. and southern Canada. The first full year of the BBS was 

1965, when Robbins reported that about 50,000 birds had 

been counted (Robbins, 1965)—a truly impressive beginning 

of what would later become the longest running systematic 

terrestrial wildlife survey in North America. Today (2016), the 

BBS remains the monitoring standard for assessing land-bird 

population trends and helps inform and guide decision making 

within the avian research and management communities (see 

the Web page developed by Dr. John R. Sauer and others at 

the Patuxent Wildlife Research Center [http://www.pwrc.usgs.

gov/bbs/bbs.html] and Sauer [2016]).

Finally, in 1965, under Dr. Dustman’s leadership, the 

Endangered Species Research program was founded and 

headed by Dr. Ray Erickson. Captive propagation at Patuxent soon gained national and international prominence, with 

efforts focused on bald eagles (Haliaeetus leucocephalus) and 

whooping cranes (Grus americana) as part of broader restoration efforts to enhance their numbers in the wild.

The Environmental Era: 1970s

With the advent of Earth Day in 1970 and the support generated during the Nixon Administration for several 

environmental initiatives, including most prominently the 

passage of the National Environmental Policy Act (1972) and 

the Endangered Species Act (1973), funding levels in the DOI 

increased dramatically. The awakening of the public with the 

publication of “Silent Spring” (Carson, 1962) and improved 

media coverage of environmental incidents converged to 

encourage greater Federal attention to scientific research. 

Patuxent benefited greatly from this momentum, hiring many 

new scientists in the areas of environmental contaminants, 

endangered species, and migratory birds. These areas later 

became separate programs within the USFWS.

In 1972, the USFWS underwent a major reorganization 

with respect to migratory birds. This move was prompted 

first by migratory bird management responsibilities within 

the USFWS that were expanding quickly and needed to be 

addressed. Secondly, personnel involved in many management-related field activities (for example, surveys and banding) often came from many different offices spread throughout 

the organization, such as the Division of Research/MBPS and 

Division of Management and Enforcement, among others, 

that complicated staffing assignments. Finally, field studies 

on key migratory bird research topics and ongoing efforts to 

analyze the wealth of banding and population data, previously 

assigned to MBPS, needed to be maintained, at a minimum, and expanded if possible. As a result, two new offices 

were formed with personnel primarily from the aforementioned divisions. The Office of Migratory Bird Management 

(MBMO) was created to function solely on the management 

side of migratory bird work, whereas the other new office, the 

Migratory Bird and Habitat Research Lab (MBHRL), retained 

migratory bird research as its primary responsibility.

In effect, the dissolution of MBPS completed the separation of research and management activities related to migratory birds within the USFWS. (Later, each regional office in 

the USFWS began to enhance in-house capacity for migratory 

bird management with the addition of a Migratory Bird Coordinator and support staff to their organizational structure.) Dr. 

John P. Rogers was selected as the first chief of MBMO, with 

George Brakhage as his assistant chief; Dr. Robert I. Smith 

became the first director of MBHRL. Bob Smith was soon 

transferred to MBMO headquarters in Washington, D.C., to 

begin work on the lead poisoning issue in waterfowl, at which 

time Dr. Fant Martin replaced him as director.

Most staff members in the new management office were 

located at Patuxent in the Branch of Surveys, although the 

chief’s office was headquartered in Washington, D.C., and 

many flyway biologists (pilots) in the Branch were assigned 

to field stations around the country. Mort Smith became chief 

of the Branch of Surveys, with Dick Pospahala as his assistant chief. Housed within this group were the Bird Banding 

Lab (George Jonkel, Chief); Waterfowl Population Surveys 

(Duane Norman, Chief, but located in Portland, OR); Harvest 

Surveys (Sam Carney, Chief); computer support and Electronic Data Processing (Bill Bauer, Chief); and staff specialist support (doves, woodcock, waterfowl), along with other 

administrative and support personnel. Similarly, most MBHRL 

personnel were also located at Patuxent, although some staff 

members were assigned to field stations around the country. 

Scientists involved in disciplines, such as environmental 

contaminants research and endangered species propagation, 

remained assigned to Patuxent. The office of the Atlantic Flyway Representative, located at Patuxent, was now attached to 

MBMO. Ed Addy had occupied this important position, first as 

a flyway biologist and then as the flyway representative, since 
34 The History of Patuxent: America’s Wildlife Research Story

the late 1940s and served as the liaison between the USFWS 

and the Atlantic Flyway Council until he retired in 1972; he 

was replaced by Warren Blandin. Both MBMO and MBHRL 

operated independently of Patuxent’s director, although all 

offices shared some administrative and maintenance support 

and contributed to overhead costs associated with the amount 

of space occupied.

In spite of the organizational separation, strong connections were sustained between the MBMO and the researchers at Patuxent. Work in the late 1960s and early 1970s was 

devoted primarily to analyzing bird-band recoveries. This 

effort was led by Drs. Charles Henny and David Anderson, 

who established a strong statistical basis for population assessment using banding data. Beginning in 1969, an in-depth 

study of the mallard was begun by biologists in both offices, 

focusing on data that had been gathered from 20 years of field 

investigations in North America. Results of this work became 

known as the “Mallard Report Series,” an eight-volume set 

of reports that ultimately improved understanding of mallard 

numbers and their relation to habitat availability and hunting 

mortality. This series, authored by many MBHRL/MBMO 

biologists, is one of the most comprehensive studies of a 

single waterfowl species available today.

Dr. Anderson, who left Patuxent in the mid-1970s for a 

USFWS Cooperative Research Unit position in Utah (then 

later moved to the Colorado Unit), set the bar high for quantitative wildlife population ecology research (see Burnham 

and Anderson, 2002). Some of his major career accomplishments that had their origins at Patuxent were in the areas of (1) 

distance sampling for density estimation, using line-transect 

methodology; (2) early computer models to facilitate bandrecovery analyses; (3) early applications of capture-recapture 

models, using Cormack-Jolly-Seber models (see reviews by 

Nichols, 1992; Williams and others, 2002) that incorporated 

information-theoretic approaches and model comparisons as 

an alternative to traditional hypothesis testing; and (4) concepts borrowed from economics and engineering, particularly 

applications of decision theory and dynamic optimization, to 

solve complex natural-resource problems. Anderson has been 

recognized both nationally and internationally as one of the 

most influential researchers in the area of wildlife science and 

biometrics in the past 50 years.

Following the departure of Dave Anderson, Dr. Jim 

Nichols was hired in 1976. Although the “shoes” of Dr. 

Anderson would prove difficult to fill, Jim Nichols continued 

the outstanding quantitative modeling work that has come 

to define modern wildlife ecology and management. Also in 

the 1970s (and later in the 1980s), additional staff members 

were hired in MBHRL and at Patuxent who would continue to 

promote strong linkages between management needs for game 

species and population ecology. These new biologists included 

biometricians and computer programmers Paul Geissler, Jim 

Hines, John R. Sauer (transferred from MBMO), B.K. (“Ken”) 

Williams, and Michael Conroy. A strong contingent of waterfowl field researchers was added as well, including Matthew 

Perry, Jerry Longcore, Michael Haramis, Ronald Kirby, 

Kenneth Reinecke, and David Krementz. Investigations such 

as the major collaboration between MBHRL scientist Matt 

Perry and research scientists at the Northern Prairie Wildlife 

Research Center in Jamestown, ND, David Trauger and Jerry 

Serie, focused on the canvasback (Aythya valisineria) and 

attempted to clarify key linkages among the breeding grounds 

in southern Canada, stopover areas along the Mississippi 

River, and the wintering grounds of Chesapeake Bay. Other 

game-bird work soon followed after the addition of new hires 

to MBHRL, including woodcock investigations in Maine (Bill 

Krohn and Tom Dwyer) and mourning dove research studies 

in South Carolina and Georgia (George Haas). Dick Coon was 

added to MBHRL staff and provided oversight to the Accelerated Research Program (ARP) in the latter half of the decade. 

Dr. Franklin Percival was selected as the first supervisor of the 

Game Bird Section.

At the same time that the Game Bird Section was gaining 

strength, the Non-Game Section in MBHRL was also adding 

research personnel, especially after the selection of Stanley 

Mike Conroy conducting survey of black ducks in New Jersey, 1981. Photo by 

Matthew C. Perry, U.S. Fish and Wildlife Service.
Migratory Bird Research, Monitoring, and Management

Migratory Bird Program: Transformations in Management and Research 35

Anderson as the section chief. Soon, Chandler Robbins would 

no longer be the “lone voice in the wilderness” regarding nongame issues and needs. Deanna Dawson (songbirds) joined 

the group, followed by Mark Fuller (raptors), Marshall Howe 

(shorebirds), Michael Erwin (colonial waterbirds), and Barry 

Noon (forest birds). Although game birds continued to be a 

major focus of the USFWS, administrators now recognized 

that major gaps existed in our knowledge of many groups of 

birds that were “off the radar screen” of management. Moreover, many species in fact seemed to be showing signs of 

severe population declines in some areas of the continent, and 

the aforementioned positions and others were filled to help 

respond to their needs. Later, during the next decade, tension 

grew within the agency over the traditional emphasis on gamebird studies as opposed to the relatively “upstart” non-game 

program. Ultimately, the passage of the Fish and Wildlife 

Conservation Act of 1980 and the 1988 amendment helped 

broaden the focus on other migratory birds and provided an 

important impetus for expanding and supporting the non-game 

program. To mitigate some of the divisiveness at Patuxent, a 

reorganization occurred that created groups without the labels 

“game” and “non-game.”

The 1970s also were busy years in MBMO, on the 

management side at Patuxent, and the Branch of Surveys 

in particular began to complete its staffing and undertake a 

number of key initiatives in addition to routine activities. New 

flyway biologists (pilots) were hired and stationed at Patuxent 

to begin training for pilot-in-command positions. During the 

1970s, these new members included Mike Cox, Jim Goldsberry, Bruce Conant, Bill Larned, and Al Novara. Staff biologist positions were also filled—Ron Reynolds (Bird Banding 

Lab), John Tautin (woodcock, following Joe Artmann), Dave 

Dolton (mourning doves), and Bob Blohm (waterfowl)—and 

key support personnel, including Judy Bladen, Phil Koscheka, 

and Fred Fiehrer, among others, were added. 

One of the important assignments for the management 

office at Patuxent was the first comprehensive review of the 

spring waterfowl breeding ground survey that had been in 

place operationally since 1955. Dr. Dave Bowden of Colorado State University was contracted to review the statistical 

underpinnings of the survey and provide guidance to the office 

on such issues as representativeness of the sampling units 

(transect segments), stratification boundaries, and variance 

estimation, among other aspects (D.C. Bowden, 1973, unpub. 

report available at the U.S. Fish and Wildlife Service, Division of Migratory Bird Management). Much of the decade 

was spent implementing many of the recommendations of this 

review. Additionally, Branch of Surveys staff members, along 

with assistance from MBHRL biologists, helped prepare the 

“FES 75,” the “Final Environmental Statement for the Issuance of Annual Regulations Permitting the Sport Hunting of 

Migratory Birds” (U.S. Department of the Interior, 1975). This 

seminal document firmly established the biological, legal, and 

administrative foundation for the annual development of hunting regulations for migratory game birds.

Jim Goldsberry and Al Novara, U.S. Fish and Wildlife Service, with aerial 

survey plane, Chesapeake Bay waterfowl survey, fall 1979. Photo by Matthew 

C. Perry, U.S. Fish and Wildlife Service.

The 1980s Computer Revolution: A PC 

in Every Office

Although MBHRL was discontinued as a research office 

in 1981, its staff and function continued under Patuxent’s 

organizational umbrella. Overall, despite this change, research 

personnel were nearly at full strength, and a great deal of 

energy and activity had developed on many fronts. Some of 

the key projects that involved close collaboration between 

MBMO staff and Patuxent’s research personnel are listed in 

table 1. The management needs of the USFWS provided the 

primary focus for most of the researchers, although some 

research addressed the needs of other interest groups, including the NPS, U.S. Forest Service, State agencies, and other 

organizations. The geographic scope was by no means limited 

to the U.S. and Canada, however. Because migratory bird 

issues do not recognize international boundaries, research 

activities expanded to a global reach. Research staff conducted 

cooperative research and conservation in Mexico, Belize, 

Jamaica, Dominican Republic, Trinidad, Suriname, Russia, 

Greenland, and France, among others.

In the early 1980s, a monumental change was evident 

in the BBL, where the staff was transitioning from manually processing banding and recovery information to using 

desktop computers. The benefits of the transition, initiated 

by Dick Pospahala with data-processing support from Phil 

Koscheka and Fred Fiehrer, in terms of time, accuracy, and 

responsiveness to the public were soon apparent. In the mid1980s, another major change occurred in the manner in which 

the government operated. Personal computers (PCs) quickly 

became available for every management, research, and administrative office, greatly facilitating the processing of information and accelerating the pace of data analysis and global 
36 The History of Patuxent: America’s Wildlife Research Story

Table 1. Examples of joint projects between migratory bird management and research personnel at the Patuxent 

Wildlife Research Center from the 1960s through the 1990s.

Title of project Period of study Major issue or question

Annual hunting 

regulations

1960s and ongoing Improve annual estimates of waterfowl breeding populations and 

levels of productivity

Shooting hours study 1979–80 Determine effects on waterfowl populations of potential changes in 

shooting times for hunting

Stabilized regulations 1980–85 Provide accurate assessments of vital rates of mallards during 

breeding and nonbreeding periods while hunting regulations are 

stabilized; continue development of mallard model

September dove hunting Late 1970s to early 1980s Determine effects of previous September season openings on 

mourning dove populations

Reward band study 1960s–90s Update previous estimates of reporting rates of bands recovered by 

waterfowl hunters, with initial focus on mallards

Woodcock Singing 

Ground Survey

1970s–80s Improve survey route selection and detection of breeding birds in 

the Northeast and Midwest

Mourning dove surveys 1980s Same issues as woodcock

May waterfowl surveys 1970s–90s Improve stratification needed for aerial surveys, especially in 

Canadian provinces; review design and other statistical aspects

Mid-Winter Waterfowl 

Inventory

1985–90 Review key design and operational aspects of mid-winter inventory; 

structure and collate aerial survey data to make flyway population 

estimation feasible, with focus on Atlantic Flyway

Colonial waterbird 

surveys 

1979–80s Improve protocols for estimating breeding populations along 

Atlantic Coast

Raptor surveys 1978–90s Develop methods for estimating raptor breeding population trends 

in the United States.

Shorebird surveys 1978–90s Improve protocols for the International Shorebird Survey, especially 

the spatial sampling frame

North American 

Waterfowl 

Management Plan

Mid-1980s—ongoing

(original plan and updates)

Integrate population and habitat information, along with research 

questions, to achieve sustainable waterfowl populations across 

North America

Adaptive Harvest 

Management (AHM)

1990s Incorporate Adaptive Resource Management (ARM) principles and 

approaches to the annual development of hunting regulations, 

focusing on the mallard
Migratory Bird Research, Monitoring, and Management

Migratory Bird Program: Transformations in Management and Research 37

information dissemination. Over the next 5 years, scientists 

became trained in a wide variety of new software for statistical 

analysis in addition to manuscript development. Gone were 

the days of decks of computer cards, carbon copies, and multilith offset printing, among other vestiges of the precomputer 

era. The new “e-mail” was catching on in the 1980s as well, 

vastly reducing the time scientists needed to spend on letter 

preparation and telephone conversations.

The advent of PCs greatly reduced the amount of time 

required for statistical analysis and modeling, as “down time” 

spent waiting for mainframe computer runs became a thing of 

the past. Major statistical programs, such as SAS, SPSS, and 

others, were adapted to perform on PCs, greatly enhancing 

the individual scientist’s capacities. One example of an area 

in which sophisticated analysis and modeling were facilitated 

by PC use was the development of the “mallard model,” a 

comprehensive effort initiated in the early 1970s by Dave 

Anderson and elaborated upon by Jim Nichols and Jim Hines 

at Patuxent, among others, to better understand the demography of the North American mallard population. Key MBMO 

scientists at Patuxent teamed with researchers at the center and 

its Vicksburg, MS, field station (Dr. Ken Reinecke) and the 

Northern Prairie Wildlife Research Center (Dr. Doug Johnson, 

Dr. Lew Cowardin, and others) to use PCs to greatly improve 

our understanding of mallard demographic parameters and 

consolidate numerical estimates of key vital rates.

One MBMO initiative in the 1980s stands out in terms of 

its purpose, scope, and involvement by research and management staff, not only at Patuxent but at many other agencies 

and organizations—an evaluation of the effect of stabilized 

hunting regulations on ducks in the U.S. and Canada. This 

program, known as the “Stabilized Regulations Study,” was a 

massive undertaking of resources and staff in both countries, 

beginning in Canada in 1979 and in the U.S. in 1980, and 

terminating in 1985. Focused on the mallard, this investigation 

attempted to answer a series of questions related to mallard 

biology and management during a period when hunting regulations (season lengths and bag limits) were held constant. The 

study culminated in many reports and peer-reviewed publications, which reflected well on the MBHRL and MBMO staff 

at Patuxent who helped design and carry out this cooperative 

undertaking (see McCabe, 1987). 

Following the conclusion of this initiative, MBMO/

Branch of Surveys staff members, along with support from 

MBHRL scientists, assisted in the preparation of “SEIS 88,” 

the “Final Supplemental Environmental Impact Statement: 

Issuance of Annual Regulations Permitting the Sport Hunting 

of Migratory Birds” (U.S. Department of the Interior, 1988). 

This important document was a follow-up to the original 

environmental impact statement published in 1975. In 1984, 

Dave Bowden was again asked to review the May aerial 

survey for breeding waterfowl and the Branch of Surveys was 

tasked with evaluating Bowden’s recommendations, culminating in a major report by Graham Smith (Smith, 1995). Finally, 

a collaborative effort of research and management scientists 

at Laurel produced an important study of reporting rates of 

banded waterfowl conducted by using reward bands. These 

studies followed an earlier investigation by Drs. Chuck Henny 

and Ken Burnham at Patuxent in the 1970s that had provided 

the most recent baseline of reporting rates of recovered bands 

available at the time. Information from the 1980s study and 

subsequent investigations ultimately helped optimize continental banding efforts of waterfowl and had a profound effect 

on BBL operations. 

The 1980s also saw many staff and organizational 

changes within MBMO that affected the migratory bird management program at Patuxent. Following the untimely death 

of Warren Blandin in 1982, Jerry Serie left a research scientist 

position at the Northern Prairie Wildlife Research Center to 

become Atlantic Flyway Representative. Sam Droege came 

to the Branch of Surveys as coordinator of the BBS when it 

was part of the migratory bird management program, and Alan 

Davenport transferred from Northern Prairie as well, bringing 

his computer expertise to the branch. Drs. Bob Trost and John 

Sauer were hired to provide biometric support to the Branch 

of Surveys, while Brad Bortner, Dave Sharp, Sean Kelly, and 

Fred Johnson added migratory game-bird expertise, joining 

other biological and administrative staff in the newly formed 

Population Assessment Section, headed by Dr. Bob Blohm. 

New pilot-biologists included John Solberg, Fred Roetker, Jim 

Bredy, Carl Ferguson, and Jim Walter, all of whom spent time 

training at Patuxent before being assigned to respective field 

stations around the country. After the departure of John Rogers 

as chief of MBMO and the retirement of George Brakhage, 

key openings in the office were soon filled by Dr. Rollin 

Sparrowe as chief, and Dr. Ken Williams as his deputy. The 

latter move further exemplified the ongoing close relationship 

between research and management programs and personnel at Patuxent, as Williams left his biometrician position in 

MBHRL to assume supervisory responsibilities in MBMO. At 

Patuxent, Dr. Robert I. Smith became Chief of the Branch of 

Surveys after Mort Smith was transferred to MBMO’s Washington, D.C., office. George Jonkel and Sam Carney retired at 

the end of the decade and were replaced by John Tautin and 

Dr. Paul Geissler, respectively. 

The “Identity Crises”: 1990s

Because of major political shifts in Washington, D.C., 

in the early and mid-1990s, two monumental reorganizations 

occurred within DOI that affected Patuxent. Then-Secretary 

Bruce Babbitt formed a new Interior science agency, known 

as the National Biological Survey (which later became the 

National Biological Service, or NBS), by combining all 

research personnel within DOI, including those from USFWS, 

NPS, and Bureau of Land Management, into one Bureau. 

Biologists at major research centers, such as Patuxent, Northern Prairie, Denver, and others, along with staff at cooperative research units located at many universities across the 

country, soon found their organizational allegiance drastically 
38 The History of Patuxent: America’s Wildlife Research Story

changed. Even the BBL and BBS at Patuxent, whose missions 

were management oriented, were caught up in this restructuring. This move was in response to criticism about science, 

policy, and regulatory authorities being located within the 

same agencies. Not surprisingly, because of this unexpected 

reorganization, Patuxent scientists and administrators suffered 

through a great deal of confusion and program uncertainty. 

Still more changes were on the horizon. In the midst of all this 

restructuring, political battles were still being waged in the 

corridors of Washington, D.C. Only 2 years after the NBS had 

been formed, discussions were underway to make yet another 

change—and this time the future of all of DOI research was 

at stake.

To “save” the approximately 1,800 scientists in NBS, 

Secretary Babbitt merged the former NBS with the U.S. 

Geological Survey (USGS) in 1996, to become a fourth 

unit, the Biological Resources Discipline (BRD), within the 

USGS. Therefore, the disciplines of water resources, geology, and mapping now included wildlife research biologists, 

biometricians, and other staff under the same organizational 

“umbrella.” Scientists at Patuxent, as well as their peers at 

former USFWS research units, faced a major redirection of 

their scientific mission, not once but twice. In migratory birds, 

instead of focusing on the trust species of the USFWS and 

issues important to national wildlife refuges and international 

treaty obligations, the former USFWS scientists now were 

obligated to deal with all the DOI land and resource issues. 

Similarly, scientists who had spent their entire careers at 

national parks conducting NPS research were asked to expand 

their scope considerably under the USGS flag, in some cases 

at a different location, such as Patuxent. Consequently, after 

merging with the USGS, Patuxent’s science plan suddenly 

looked very different within an agency whose culture had 

historically been defined by the physical sciences. Gone was 

a “migratory birds” program, as well as separately funded 

programs for contaminants or endangered species. Instead, 

more generic scientific objectives were established that, in 

the biological discipline, focused on ecosystem research, with 

little emphasis on population-level science or species conservation concerns.

Following several changes in USGS directors since 1996, 

administrative alignments and objectives too have changed; 

moreover, after more than a decade, the former USFWS 

and NPS biologists have acclimated to the new research 

model. Another shift in the paradigm has been the fostering 

of researcher alignments with research universities. These 

cooperative arrangements have long been part of the culture 

of the USFWS (the Cooperative Fish and Wildlife Research 

Unit program) and NPS (Cooperative Parks Studies Unit 

program), but most researchers in the USGS traditionally 

had been based at a small number of centers independent of 

university campuses (for example, Menlo Park, CA; Woods 

Hole, MA; and Reston, VA [USGS headquarters]). Today, the 

presence of biologists at universities across the country has 

spawned the formation of many local and regional partnerships addressing a wide variety of fish and wildlife resource 

issues. In addition, these strong university ties have facilitated 

the training of many graduate and post-graduate students by 

Patuxent scientists.

In spite of this functional upheaval in the traditional 

pursuits of wildlife ecology, conservation, and management, 

many important projects and advancements occurred during 

the 1990s and early 2000s. Many of these involved extensive 

interactions among Patuxent researchers, visiting scientists 

and post-doctoral students, and migratory bird management 

personnel in the USFWS and other agencies. Again, one 

contributing factor was the increasing use of PCs, which 

improved the efficiency of model development and prompted 

other innovative statistical approaches, making them more 

accessible to the wider scientific community around the world. 

Jim Hines, a longtime associate of Jim Nichols, became one 

of the country’s premier computer programmers in the area of 

wildlife demographic modeling. His development of userfriendly software has enabled wildlife researchers worldwide 

to access upgraded capture-recapture models for closed and 

open populations, occupancy models for metapopulation 

analyses, and other decision-support tools. The importance of 

this long-term, productive collaboration between Nichols and 

Hines cannot be overstated.

Within the Migratory Bird program of the USFWS, the 

decade of the 1990s was highlighted by major changes in a 

longstanding survey effort centered at Patuxent and by a major 

paradigm shift in the decision-making process with respect 

to establishing annual harvest regulations. Not unexpectedly, staffing and organizational changes occurred during this 

decade as well.

Although problems with response rates in the harvest survey program had been recognized previously, levels reached 

unacceptable lows in the 1980s, prompting the waterfowl 

management community, particularly the USFWS, to seek 

alternative approaches. Initiated at the request of the International Association (now Association) of Fish and Wildlife 

Agencies in 1991, the new Harvest Information Program 

(HIP) moved away from the previous sampling frame based 

on duck stamp purchases to one that required licensed hunters 

to identify themselves as migratory bird hunters and supply 

name, address, and other information necessary for subsequent sampling efforts. Following a pilot stage and staggered 

entrance of states into the new system, the HIP survey became 

fully operational in 1998 and today stands as a much more 

reliable method for assessing hunter activity and success, not 

only for waterfowl but for other species of migratory game 

birds as well. Dr. Paul Padding, newly hired to the Harvest 

Surveys staff at Patuxent, provided overall guidance that 

contributed to the program’s successful development and 

implementation, with critical assistance from Dr. Paul Geissler 

(formerly of MBHRL), Mary Moore, Bob Jessen, and Larry 

Hindman (Maryland Department of Natural Resources).

Against the backdrop of declining duck populations in 

the 1980s, ongoing high demand for more hunting opportunities, and longstanding uncertainty about the effects of hunting 

on migratory bird populations that continued to generate high 
Migratory Bird Research, Monitoring, and Management

Migratory Bird Program: Transformations in Management and Research 39

levels of controversy, the stage was set in the early 1990s for a 

dramatic change in the annual regulations-setting process for 

waterfowl hunting. Beginning in 1992, MBMO, along with 

research scientists at Patuxent and with the support of all four 

Flyway Councils, embarked on a long but successful collaboration to bring about needed changes in harvest management. 

The objectives of this cooperative effort were to help improve 

managers’ understanding of the effects of hunting regulations 

on harvests and population levels, to maximize cumulative 

harvests over the long term, while maintaining waterfowl 

populations at or above objective levels, and at the same time 

to provide a more informed and objective decision-making 

process for addressing harvest management issues each year. 

This process, an outgrowth of Adaptive Resource Management (ARM), focused from the beginning on the population 

dynamics and harvest potential of mallards. It became known 

as Adaptive Harvest Management (AHM) and was fully 

implemented in 1995. Although many individuals contributed 

to AHM’s development and implementation over the years, the 

hub of activity was at Patuxent, where Fred Johnson (MBMO) 

provided the theoretical framework, along with Jim Nichols, Ken Williams, Graham Smith, Bob Trost, Bill Kendall, 

Jim Dubovsky, Dave Caithamer, and later Scott Boomer and 

Mike Runge, and many others in the research and management offices. This highly successful program continues to this 

day, and its value to waterfowl management can be directly 

attributed to the involvement from the beginning of biologists 

from Federal, State, and nongovernmental agencies (NGOs) 

and organizations.

The New Millennium: Research into 

New Dimensions

Once the wildlife programs were merged with other 

USGS research priority areas, the momentum shifted away 

from traditional species and community approaches to 

consider topics such as ecosystem dynamics, global climate 

change, and environmental health. Although new allegiances 

and partnerships were being formed within and outside the 

USGS community, and despite changing scientific missions, 

the legacy of wildlife population dynamics at Patuxent managed to continue uninterrupted. As proof, a major manuscript 

was completed early in the 2000s and published in book form, 

marking the culmination of two decades of work on population demographic analysis and effective wildlife management 

(Williams and others, 2002). The authors —Ken Williams, 

Mike Conroy, and Jim Nichols—were all collaborating Patuxent researchers in the 1980s, although Williams and Conroy 

later left for other positions.

Increasing concern about climate change in the Federal 

science agencies resulted in major funding initiatives for 

Patuxent and other USGS research facilities. Patuxent scientists focused on studying possible effects of coastal sea-level 

rise on lands under management policies of the USFWS, NPS, 

States, and NGOs. Don Cahoon, Glenn Guntenspergen, and 

Mike Erwin all initiated studies at many Atlantic coastal (and 

international) sites in which surface elevation tables were used 

to compare marsh dynamics to relative sea-level rise.

On the management side, the 2000s marked an expansion 

of the biological staff at Patuxent. The Branch of Population 

and Habitat Assessment (formerly the Population Assessment 

Section), with Mark Koneff as chief, added many migratory 

bird specialists, including nongame biologists—many with 

advanced quantitative skills—who collectively provided a 

level of expertise in population ecology and modeling matched 

only by Patuxent’s USGS scientists. In addition to carrying out 

traditional responsibilities related to operational surveys and 

the annual regulations development process, staff members 

provided continued support to AHM and HIP, and embarked 

on new initiatives. Some of these included waterfowl population survey improvements (Emily Silverman); development of 

more informed, model-based harvest strategies for woodcock 

(Guthrie Zimmerman) and mourning doves (Mark Seamans, 

Todd Sanders); additional reporting rate investigations (Pam 

Garrettson, Andy Royle); and adaptive harvest strategies for 

waterfowl other than mallards (for example, northern pintails 

[Anas acuta], Mike Runge [Patuxent]; American black ducks, 

Mike Conroy [USGS, retired], Pat Devers; and scaup [Aythya 

affinis and A. marila], Scott Boomer). 

In the 2000s, the longstanding work and collaboration on 

AHM at Patuxent finally began to have far-reaching ramifications in the natural-resource community. Because of the ongoing success of AHM in helping biologists manage waterfowl 

harvests, and because of the willingness of key individuals in 

research and management to share their knowledge and understanding of this new management approach, a paradigm shift 

in the way natural-resource issues could be resolved was taking place outside the migratory bird management arena. Today, 

ARM has been accepted within DOI as a policy approach 

for resolving natural-resource management issues on Federal 

lands and for helping to fulfill Federal mandates for trust species. Some of the projects involving substantial management 

input to the research planning process during the past decade 

are listed in table 2. The first eight projects listed involve a 

continuation of the linkages between the management personnel (formerly MBMO, renamed Division of Migratory Bird 

Management in 2000) and researchers at Patuxent, including 

the BBL. The remaining projects involve substantial input 

from the refuge component of the USFWS and from the NPS. 

Additional shared research/management projects that have 

emerged include management activities within other State, 

Federal, and international agencies, such as:

1. Avian disease ecology—Since 2005, with the outbreak 

of avian influenza in bar-headed geese (Anser indicus) 

at Qinghai Lake in western China and its potential for 

global spread to humans, Patuxent and other USGS 

facilities have been engaged in research in east Asia 

(Jiao, 2010). The “management” agencies now include 

the United Nations Food and Agriculture Organization, 

USFWS, USGS, USDA, and many Chinese science and 
40 The History of Patuxent: America’s Wildlife Research Story

Table 2. Recent (1990s to present [2016]) projects involving collaboration of Patuxent Wildlife Research Center migratory 

bird researchers with management personnel on studies of mutual interest, and related scientific advances.

Title of project or study Time period Related scientific advances

Capture-recapture modeling 1990s and 

ongoing

Expansion of applications to estimate species richness; development 

of methods for coping with detectability differences, multistate 

populations, and missing data; development of user-friendly software

Occupancy modeling 1990s and 

ongoing

Expanded use of models to consider larger metapopulation dynamics, 

colonization, dispersal, range shifts, and epidemiology; software 

development

Status of migratory bird 

populations across the United 

States and Canada

1990s and 

ongoing

Accessibility of summary results from Breeding Bird Survey to 

increase knowledge of status and trends of many North American 

landbirds and some game-bird species

Adaptive management of 

migratory game-bird species

1990s and 

ongoing

First application of Adaptive Resource Management (ARM) principles 

to harvest regulations for mallards, American black ducks, and other 

species and populations of waterfowl

Additional reward band studies 1990s and 

ongoing

Availability of reporting rate information available for other species 

besides mallards; optimization of banding needs

Updated Supplemental 

Environment Impact 

Statement 88 

2006–11 Updated information that supports the biological, legal, and 

administrative aspects of promulgating annual hunting regulations 

for migratory game birds

Improved harvest strategies for 

migratory game birds

1990s and 

ongoing

Improved use of available information to make more informed harvest 

management decisions

Priority research and management 

needs for migratory shore and 

upland game birds

2006–11 Identification of top research and management activities to address 

needs; enhancement of funding request justifications

Wetland mitigation studies 1990–98 Improved approaches to water management on Patuxent Research 

Refuge property

Coastal sea-level rise on Federal 

lands

1998 and ongoing Use of surface elevation tables on refuges and National Park Service 

lands to evaluate refuge and other Federal lands most vulnerable to 

sea-level rise

Open marsh water management 

on Federal lands

1999–2006 First large-scale experimental approach to studying effects of 

hydrologic manipulations on salt-marsh environments

Integrated Waterbird Monitoring 

and Management

2009 and ongoing Application of principles of ARM and Structured Decision-Making 

(SDM) to wetland management in the eastern United States to 

optimize use by a diverse water-bird community

Wind turbine impacts in eastern 

mountain ridges

2005 and ongoing Experimental application of acoustic receptors at proposed turbine 

locations in the Appalachian region; documentation of bird and bat 

impacts

Seaduck movements and trophic 

relations

2004 and ongoing Discovery of new routes used during migration and staging in Canada; 

collection of new energetic information (captive flock)
Migratory Bird Research, Monitoring, and Management

Migratory Bird Program: Transformations in Management and Research 41

forest agencies. The research activities have expanded 

from using satellite telemetry to monitor selected species 

of waterfowl in China and Mongolia to developing 

risk models based on poultry farm distributions and 

wildlife migration movements in eastern Asia (see 

http://www.usgs.gov/blogs/features/usgs_science_pick/

understanding-global-avian-influenza-transmissionpathways-through-ecology/). Other USGS researchers 

have added study sites in Africa and parts of the Middle 

East to the East Asian locations. Close coordination with 

the USFWS was facilitated by the 2008 hiring of an Avian 

Disease Coordinator, Dr. Samantha Gibbs, in the DMBM.

2. Structured Decision-Making (SDM)—The increased 

complexity of natural resource issues, many of which 

have competing demands, has led to the emergence of a 

new paradigm to formulate effective management planning. The popularity of SDM, an outgrowth of ARM, has 

increased among Federal agencies over the past several 

years (Martin and others, 2009). One demonstration of 

it has been on a multirefuge study across the Northeast 

and Midwest to assess impoundment management for 

waterbirds (Lyons and others, 2008). The approach, many 

of whose elements are borrowed from systems theory, has 

broad appeal to a wide audience of managers. Challenges 

in determining the timing and spatial scale of management implementation can be addressed using SDM. Also, 

the SDM approach can be useful in seeking optimal 

solutions where many management objective functions 

have been identified. Patuxent and DMBM scientists have 

offered training classes in SDM applications.

3. Offshore energy infrastructure—The need for exploration to discover additional energy sources, including 

wind generation and new oil/natural gas fields, demands 

that environmental impacts be evaluated. In the past 5 to 

6 years, Patuxent has been engaged with the Bureau of 

Ocean Energy Management (formerly Minerals Management Service), the USFWS, and several State agencies 

and NGOs in evaluating the potential for impacts of 

turbine or rig installations on migratory birds. Some of 

the research has focused on marked individual seaducks 

in Nantucket Sound, MA, including the identification of 

their foraging and roosting locations during winter, in 

conjunction with a broader seaduck study in the U.S. and 

Canada. In addition, a large database has been developed 

to capture available information on seabird distributions 

along the entire Atlantic Coast.

4. Island restoration—The demands of shipping and maintenance of navigation channels along the coast require 

the U.S. Army Corps of Engineers and State management 

agencies to coordinate disposal plans for millions of cubic 

yards of dredged materials. One such large-scale project 

that has involved Patuxent since the mid-1990s is the 

Paul Sarbanes Ecosystem Restoration Project at Poplar 

Island in Talbot County, on Maryland’s Eastern Shore 

(see http://www.nab.usace.army.mil/About/ProjectFactSheets.aspx). This “Beneficial Use” project requires that 

the restoration of the approximately 1,150-acre island provides equal areas of uplands (up to about 8.6 yards above 

North American Vertical Datum of 1988) and wetlands. 

The objective for the wetland area is to attract key species 

of nesting and migrating waterbirds, nesting diamondback 

terrapins (Malaclemys terrapin), fishes, and other species. 

Patuxent scientists have been major participants in habitat 

design for the project area and monitoring of use by 

waterbirds and breeding success since 2002 (Erwin and 

others, 2007).

Conclusions

Patuxent’s program for migratory birds, like most Federal 

programs, has been altered dramatically over the past 80 years 

as bureaus reorganized, administrations forced a reexamination of priorities, funding levels fluctuated, and scientific 

personnel came and went. Nevertheless, the level of scientific 

activity has remained consistently high, with Chandler Robbins serving as the “guiding light” in his 60 years of dedicated 

research service. Scientists located at Patuxent and working 

in either wildlife research or wildlife management have taken 

active roles in forging new initiatives in a number of key areas 

over the years. Some examples are—

• Managing aquatic vegetation in impoundments to support waterfowl;

• Expanding the capabilities and efficiency of the BBL to 

allow sophisticated distribution and population analyses of both hunted and nonhunted species of birds;

• Developing rigorous national/international bird surveys 

for waterfowl, woodcock, mourning doves, and other 

webless migratory game-bird species to support the 

promulgation of annual hunting regulations;

• Improving or formulating more effective inventory and 

monitoring methods for songbirds, shorebirds, raptors, 

and colonial waterbirds, and extending the training to 

a number of underdeveloped countries in the Western 

Hemisphere;

• Initiating the BBS across the U.S. and Canada, and 

later making the summaries of trends of species available on the World Wide Web;

• Developing and expanding new applications of 

capture-recapture and occupancy modeling beyond 

estimating survival and abundance parameters of 

populations;

• Applying ARM and SDM to complex natural resource 

problems, including more informed management of 

harvests of migratory game birds;
42 The History of Patuxent: America’s Wildlife Research Story

• Drafting national plans to manage and conserve waterfowl, waterbirds, shorebirds, and raptors; and

• Studying the movements of waterfowl in East Asia 

and investigating mechanisms of the transmission and 

spread of avian influenza (H5N1) within wild populations and among wild and domesticated poultry during 

seasonal movements.

The inclusion of Patuxent as part of the USGS—an 

agency dominated by the physical sciences—has broadened 

its purpose, and studies of migratory birds continue in different forms. More specifically, studies of bird populations and 

the development of methods for effectively managing those 

populations are now typically cast in relation to predicted 

climate change, threats to conservation, effects of mineral and 

energy facility expansion, and considerations of human and 

animal health.

Within the USFWS, a separate programmatic home, apart 

from the Refuge program, was created for migratory birds 

in the early 2000s under a new assistant director (first, Tom 

Melius as Assistant Director for Migratory Birds and State 

Programs in 2000; and later, Paul Schmidt as Assistant Director for Migratory Birds in 2003). This change provided many 

obvious benefits and advantages in terms of priority-setting 

and program delivery. In recent years, however, a broadening 

of the program’s mission has been observed in this agency as 

well, with more involvement of migratory bird staff, including 

those at Patuxent, in large-scale initiatives on the landscape.

Another challenge for both the USGS and USFWS in the 

future is coordination among the many Federal, NGO, State, 

university, and other agencies and organizations interested in 

both research on and management of birds and their habitats at 

different scales. Just a partial list reveals how large the scope 

of partnerships has become: regional, national, and international Joint Ventures and other bird conservation plans under 

the North American Waterfowl Management Plan and North 

American Bird Conservation Initiative (NABCI); the new 

USGS National Climate Change and Wildlife Center, with 

eight centers distributed around the county; the new Landscape Conservation Cooperatives (joint Federal and university 

projects, with USFWS and USGS); The Nature Conservancy’s 

Conservation By Design program; and others, such as programs shared with Ducks Unlimited, the U.S. Forest Service, 

and various State programs (for example, Florida’s Forever 

Wild). Without a scorecard, it will be very difficult to keep up 

with developments in all these initiatives to reduce redundancy 

and overlap. In these times of very limited public funding, it is 

essential to ensure that management and research dollars are 

allocated in the most effective way possible.

Finally, Patuxent’s many accomplishments over the last 

80 years could not have been achieved without a conscious 

effort on the part of research and management staff to maintain longstanding and productive working relationships. These 

professional bonds formed at Patuxent have ensured continual collaboration among staff, despite those many factors, 

both internal and external, that have continued to threaten 

program viability. It is a rich history and a lasting testament 

to these individuals that research and management programs 

at Patuxent have sustained their high visibility and value to 

the conservation and management of our natural resources for 

three-quarters of a century. There is no reason to believe that 

this relationship will not endure well into the future.

Acknowledgments

We thank Matthew Perry for inviting this paper as a 

contribution to the 75th anniversary of the Patuxent Wildlife 

Research Center, and Lynda J. Garrett for assistance with 

library reference materials. Fred Glover, Paul Padding, Jerry 

Serie, Doug Benning, and Jim Voelzer provided helpful comments on earlier drafts of this manuscript.

Tom Custer weighing heron chick at a dredge island site in Lavaca Bay, 

Calhoun County, TX, in 1988. Photo by R. Will Roach, U.S. Fish and Wildlife 

Service.
Migratory Bird Research, Monitoring, and Management

Migratory Bird Program: Transformations in Management and Research 43

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McCabe, R.E., 1987, Results of stabilized duck hunting regulations: Transactions of the North American Wildlife and 

Natural Resource Conference, v. 52, p. 177–326.

Meanley, Brooke, 1975, Birds and marshes of the Chesapeake 

Bay country: Cambridge, MD, Tidewater Publishers, 157 p.

Meanley, Brooke, and Webb, J.S., 1963, Nesting ecology 

and reproductive rate of the red-winged blackbird in tidal 

marshes of the upper Chesapeake Bay region: Chesapeake 

Science, v. 4, no. 2, p. 90–100. [Also available at http://

dx.doi.org/10.2307/1350827.]

Nichols, J.D., 1992, Capture-recapture models—Using 

marked animals to study population dynamics: BioScience, 

v. 42, no. 2, p. 94–102. [Also available at http://dx.doi.

org/10.2307/1311650.]

Robbins, C.S., 1965, Fifty thousand birds recorded on Breeding Bird Survey: Maryland Birdlife, v. 21, no. 3, p. 73–79.

Sanderson, G.C., ed., 1977, Management of migratory shore 

and upland game birds in North America: Washington, 

D.C., International Association of Fish and Wildlife Agencies, 358 p.

Sauer, J.R., 2016, Patuxent’s role in the development of the 

Breeding Bird Survey, in Perry, M.C., The history of Patuxent—American’s wildlife research story: U.S. Geological 

Survey Circular 1422, p. 53–64. 

Smith, G.W., 1995, A critical review of the aerial and 

ground surveys of breeding waterfowl in North America: 

Washington, D.C., U.S. Department of the Interior, 

National Biological Service, Biological Science Report 

5, 252 p. [Also available at http://www.dtic.mil/cgi-bin/

GetTRDoc?AD=ADA322667.]

Steenis, J.D., and Stotts, V.D., 1965, Tidal dispersal of herbicides to control Eurasian watermilfoil in the Chesapeake 

Bay: Proceedings of the Southern Weed Conference, v. 18, 

p. 507–511.

Stewart, R.E., and Robbins, C.S., 1958, Birds of Maryland 

and the District of Columbia: Washington, D.C., U.S. Fish 

and Wildlife Service, North American Fauna No. 62, 401 p. 

[Also available at http://www.fwspubs.org/toc/nafa//62.]

Uhler, F.M., 1954, Water chestnut menaces upper section of 

Chesapeake Bay: Maryland Sportsman, v. 12, no. 9, p. 4–5.

U.S. Department of the Interior, 1975, Issuance of annual 

regulations permitting the sport hunting of migratory birds: 

Washington, D.C., U.S. Fish and Wildlife Service, Final 

Environmental Impact Statement, 710 p. plus appendixes.

U.S. Department of the Interior, 1988, Issuance of annual 

regulations permitting the sport hunting of migratory birds: 

Washington, D.C., U.S. Fish and Wildlife Service, Final 

Supplemental Environmental Impact Statement, 340 p.

U.S. Fish and Wildlife Service, 1972, Population ecology of 

migratory birds: Washington, D.C., U.S. Fish and Wildlife 

Service, Wildlife Research Report 2, 278 p.

Williams, B.K., Nichols, J.D., and Conroy, M.J., 2002, Analysis and management of animal populations (1st ed.): San 

Diego, CA, Academic Press, 817 p.
44 The History of Patuxent: America’s Wildlife Research Story

Blue-winged teal, Little Compton, RI, 1966. Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.
Migratory Bird Research, Monitoring, and Management

The Bird Banding Laboratory: Support for and 

Collaboration with Research at Patuxent

By John Tautin

Located at Patuxent Research Refuge (PRR) and 

functionally part of the Patuxent Wildlife Research 

Center (Patuxent), Laurel, MD, the Bird Banding Laboratory (BBL) is the service and administrative center 

for bird banding in the United States. Over the years, 

the BBL has been associated with both the PRR and 

Patuxent, which collectively are commonly referred 

to by the public (and in this chapter) as “Patuxent.” 

The BBL issues permits and bands; supplies banding software, instructional materials, and technical 

advice; coordinates the use of auxiliary markers such 

as neck collars and radio transmitters; serves as the 

repository for banding records and the clearinghouse 

for reports of banded birds; disseminates data to 

researchers and managers; and assists in the development and coordination of banding projects. The 

BBL is a large and complex operation with a long and 

rich history that predates its transfer to PRR in 1942, 

when it began a remarkably successful and mutually 

beneficial collaboration with research and management functions colocated at PRR. Prior to 1961, the 

BBL was known simply as the “bird banding office.”

Bird Banding Begins: The Bird Banding 

Laboratory before Patuxent

Scientific bird banding began in 1902, when Smithsonian 

Institution scientist Dr. Paul Bartsch banded several blackcrowned night-herons (Nycticorax nyticorax) along the Anacostia River in Washington, D.C. Bartsch used serially numbered bands with a Smithsonian return address on them and, 

in 1904, he published results from his banding study (Bartsch, 

1904). In a prescient statement that began, “There are still 

many unsolved problems about bird life....” Bartsch suggested 

that bird banding would become a useful scientific tool.

Indeed, banding caught on quickly in the U.S. and 

Canada (Cole, 1922; Jackson, 2008). It was managed privately 

until 1920, when the Federal bird banding office was established in Washington, D.C. Federal involvement in bird 

banding was both logical and welcome. The 1916 Convention between the U.S. and Great Britain (for Canada) for the 

Protection of Migratory Birds had established Federal preeminence in migratory bird matters, and the subsequent 1918 

Migratory Bird Treaty Act made it law. The banding community actually encouraged the entry of the Federal government 

into the management of bird banding. World War I was underway, private support for banding had waned, and an entity 

with sufficient resources and authority to manage bird banding 

was needed. That entity was determined to be the already wellestablished U.S. Bureau of Biological Survey (Bureau).

The Bureau had some experience with bird banding (Wetmore, 1915), and Bureau administrators, notably Edward Nelson, Bureau Chief, and Harry Oberholser, head of bird studies, 

were supportive and recognized the need for a well-organized, 

central banding office. Therefore, in 1920, in arguably one 

of the most fortuitous appointments in the history of North 

American ornithology, they recruited Frederick C. Lincoln to 

organize the bird banding office (Tautin, 2008).

Lincoln was a remarkably accomplished biologist, writer, 

and administrator. By the end of the 1920s, he had organized the banding office, developed numbering schemes and 

record-keeping procedures, established standards, recruited 

bird banders, and fostered international cooperation. He was 

also a visionary who tirelessly promoted banding as a tool in 

scientific research and management. His contributions were 

significant and included the development of the Lincoln index 

(Lincoln, 1930; later modified to become the Lincoln-Petersen 

index), which ultimately proved to be a true population estimator (Nichols and Tautin, 2008), and the flyways concept 

(Lincoln, 1935), which is still applied in waterfowl management today. As his career progressed, Lincoln took on additional responsibilities, but he remained the primary official 

of the bird banding office until 1946, overseeing its transfer 

from Washington, D.C., to Patuxent in 1942. Lincoln retired 

in 1947, leaving a remarkable legacy. Much has been written 

about his career and achievements (Terres, 1947; Gabrielson, 

1961; Reeves, 1984; Tautin, 2005). Frederick C. Lincoln truly 

was the founder of the bird banding program as we know 

it today.
46 The History of Patuxent: America’s Wildlife Research Story

The Bird Banding Office Moves to 

Patuxent

World War II prompted the move of the bird banding 

office to PRR. During the summer of 1942, in accordance 

with a decentralization order by President Roosevelt, the main 

offices of the U.S. Fish and Wildlife Service (USFWS) were 

moved temporarily to Chicago. However, the bird banding and 

other migratory bird files, together with the staff members who 

worked with those files, were moved to PRR (later Patuxent), 

where space in Nelson Laboratory was available.

After the war, the USFWS returned to Washington, 

D.C., but the bird banding office stayed at Patuxent, where it 

remains today, known as the BBL. The move to Patuxent was 

most fortunate for bird banding, because Patuxent would eventually become a world-class center for migratory bird research 

and management. The colocation of the bird banding office 

with scientists, who developed methods for analyzing banding 

data, and with management-oriented biologists, who used the 

data, proved to be mutually beneficial.

Lincoln remained in Washington, D.C., but retained 

administrative responsibility for the bird banding office 

through 1946. Management assistance at Patuxent was 

provided by May Thacher Cooke; two clerks, Marge Stewart and Lois Horn; biologist Chandler Robbins, beginning in 

1943; and John Aldrich, who had transitional responsibilities 

between Lincoln’s retirement and the appointment of Seth H. 

Low as the head of the bird banding office on January 5, 1948 

(Steele, 1948; A.J. Duvall, 1968, unpublished letter on file at 

the U.S. Geological Survey Bird Banding Laboratory, Patuxent Wildlife Research Center, Laurel, MD).Low served in that 

capacity until 1954, when Allen J. Duvall transferred from 

the Museum of Natural History to PRR, where he was put 

in charge of migratory bird work, including the bird banding 

office. In a 1961 reorganization at Patuxent, the bird banding 

office was formally designated the Bird Banding Laboratory 

(BBL), and its leader, Duvall, was designated “Chief.” Duvall 

Seth Low, second chief of the Bird Banding Laboratory, Laurel, MD, 1951. 

Photo by Chandler S. Robbins, Patuxent Research Refuge.

remained BBL Chief until 1964, when he assumed a position 

with the Pesticides Review Board in Washington, D.C. The 

designations “BBL” and “Chief” remain today.

The internal written record of BBL’s support for research 

during the tenures of Low and Duvall is relatively sparse, 

but that support was very likely given. Evidence exists in the 

form of external publications, notably two written by Aldo 

Leopold proteges Arthur S. Hawkins (1949) and Joseph J. 

Hickey (1952), who spent time at Patuxent researching the 

files at BBL.

Post-War Developments Influence Bird 

Banding

Outside the bird banding office during the late 1940s and 

1950s, much was happening that would influence the office 

for decades to follow. As the Nation returned to “business as 

usual” after World War II, many young war veterans went to 

college under the Servicemen’s Readjustment Act of 1944 

(G.I. Bill), with increasing numbers entering the developing field of wildlife management. Surplus aircraft were made 

available for waterfowl surveys. Reliable funding from the 

Wildlife Restoration Act of 1937 (Pittman-Robertson Act) 

helped the States match the Federal Government’s investment in waterfowl management. These efforts were stimulated 

by the resurgence of waterfowl hunting after G.I.s returned 

home and sporting ammunition became readily available. The 

development of cooperative bodies such as the four Flyway 

Councils furthered growth in waterfowl management. By 

1960, State and Federal agencies were implementing cooperative, integrated, large-scale breeding ground surveys, harvest 

surveys, and banding programs specifically designed to yield 

data needed for waterfowl management. Martin and others 

(1979) and Hawkins and others (1984) provide interesting and 

comprehensive histories of these developments.

Allen J. Duvall, third chief of the Bird 

Banding Laboratory, Laurel, MD, 

1961. Photo by U.S. Fish and Wildlife 

Service.
Migratory Bird Research, Monitoring, and Management

The Bird Banding Laboratory: Support for and Collaboration with Research at Patuxent 47

Laverne Casteline checking schedules, Bird Banding Laboratory, Laurel, MD, 

1951. Photo by U.S. Fish and Wildlife Service.

Waterfowl Concerns Dominate at the 

Bird Banding Laboratory during the 

1950s and 1960s

During the 1950s and 1960s, Patuxent became a leader 

in developing and managing surveys that supported research 

on and management of migratory game birds. In a supporting 

role, the BBL followed suit. The BBL adopted permit and data 

policies that clearly favored game-bird banding. Operational 

procedures were developed to accommodate game-bird interests; for example, banding and recovery records were modified 

to include codes for flyways, and all recovery records contained a “hunting seasons survived” code, even for nongame 

birds. Large numbers of waterfowl being banded reflected the 

emphasis on game-bird banding, and soon the mallard (Anas 

platyrhynchos) became the most frequently banded bird in 

North America, a distinction that it holds to this day.

The BBL modernized data management in the early 

1960s, partly to better serve research and management, and 

partly in response to a disastrous fire that destroyed many 

paper banding records in 1959. Chan Robbins explains that 

few records were actually lost in the fire, but all the punch 

cards were distorted or singed from the heat and had to be 

replaced (Chandler Robbins, U.S. Fish and Wildlife Service, 

oral commun., 1983). BBL staff and other Patuxent personnel spent approximately 2 years reconstructing the file after 

the fire. Entry into the newly emerging field of electronic data 

management was accelerated in the mid-1960s with the installation of a modern IBM® computer capable of managing the 

now millions of banding records being used by scientists at 

Patuxent and other locations. Added impetus to modernization 

efforts at the BBL arrived in late 1964 with the appointment 

of the engaging and energetic Earl B. Baysinger as the fourth 

BBL chief.

By the mid-1960s, the importance of the BBL’s role in 

supporting research and management programs in the U.S. and 

Canada was recognized at the highest agency levels in Washington, D.C. In January 1967, the General Services Administration announced plans for the construction of a $1.1 million 

Bird Banding Records Center at Patuxent (The Washington 

Post, 1967). Construction was completed promptly, and in 

1968 the BBL was housed in its new, state-of-the-art home 

named Gabrielson Laboratory (U.S. Fish and Wildlife Service, 

1972) in honor of Ira N. Gabrielson, an accomplished ornithologist, conservationist, and former director of the USFWS. 

Gabrielson Laboratory offered far more space than the BBL 

needed, and therefore was soon filled by other offices, including the Migratory Bird Populations Station and a burgeoning 

computer section. The BBL remains housed in Gabrielson 

Laboratory at Patuxent to this day (2016).

New Analytical Models Begin to 

Influence Bird Banding

During the 1960s, a quiet, but profound, revolution in

banding data analysis had begun outside the BBL and Patuxent with the development of the Jolly-Seber-Cormack models 

(Nichols and Tautin, 2008). Statistically, these models were 

vastly superior to the then commonly used life tables. Over the 

next four decades, these new models would lead to a tremendous expansion of analytical methods that would further validate the importance of banding data, and therefore the BBL, 

to research. As was historically the case with many developments in bird banding, this one also was driven by game-bird 

management priorities. Waterfowl management and the setting 

of annual hunting regulations was becoming more complex, 

and Federal and State agencies needed more accurate scientific 

results from banding (Tautin, 1993).

Helen Webster punching return card, Bird Banding Laboratory, Laurel, MD, 

1951. Photo by U.S. Fish and Wildlife Service.
48 The History of Patuxent: America’s Wildlife Research Story

The availability of these statistically reliable models, 

particularly the so-called Seber-Robson-Brownie models for 

estimating survival and recovery rates from band recovery 

data (Brownie and Robson, 1976), led to the publication of the 

eight seminal “Mallard Reports” by Patuxent scientists (for 

example, Anderson and Burnham, 1976). In the 1970s, two of 

those scientists, David Anderson and Ken Burnham, moved 

from Patuxent to Colorado State University and collaborated 

with Gary White to produce many more reports related to the 

analysis of bird banding data. In testimony to their enduring contributions to wildlife conservation, all three later 

received the Aldo Leopold Award, the wildlife field’s most 

prestigious honor.

Nongame-Bird Banding Comes of Age

During the 1970s and 1980s, game-bird considerations 

continued to dominate the banding program, but several events 

caused nongame-bird banding to become more prominent. The 

Endangered Species Act of 1973 formally gave the USFWS 

responsibility for threatened and endangered birds, most of 

which were nongame birds. Universities and colleges began 

to employ more ornithologists and, by the end of the 1980s, 

nearly one-third of all banders had an academic affiliation. 

Research centers like Patuxent devoted increasing attention to 

nongame-bird species. As evidenced by the many published 

reports cited in the other chapters in this volume, Patuxent in 

particular became renowned for its work with both endangered 

and nonendangered birds.

Institutional banders at Patuxent and in the broader ornithological community, having more scientific knowledge than 

nonprofessional banders, commonly used auxiliary markers 

such as colored leg bands, neck collars, and radio transmitters that yielded additional and more accurate data. The BBL 

worked closely with them to ensure that advanced marking 

techniques were both effective and safe for birds. For some 

widely studied species, the BBL also worked with banders and 

other stakeholders to develop cooperative marking protocols. 

These cooperative efforts led to a great increase in observations of marked birds that supported the use of analytical 

models, which had moved rapidly beyond game-bird band 

recovery models to include more versatile mark-recapture 

models well suited for nongame-bird studies.

Nongame-bird banding received an additional boost 

during the 1970s and 1980s after George Jonkel became the 

fifth BBL chief in 1971. Jonkel had been with the USFWS for 

many years, and had been an active bander of both game and 

nongame birds. Under Jonkel’s leadership, the BBL encouraged and supported nongame-bird research by both professional and amateur banders, and maintained close ties to the 

amateur regional banding associations.

Furthermore, during this era and into the next millennium, BBL chiefs and staff biologists, themselves licensed 

bird banders, also lent “hands-on” support to banding projects 

at Patuxent and other banding places. Some examples were 

John Tautin’s and B.H. Powell’s tours of duty banding ducks 

in Canada under the cooperative prehunting-season banding 

program, Kathy Klimkiewicz’s decade-long study of wintering 

birds, Danny Bystrak’s long-term study of fall migrants on the 

Patuxent powerline right-of-way, Mary Gustaphson’s operation of a constant effort banding station under the USFWS 

continent-wide Monitoring Avian Productivity and Survivorship program, and Bruce Peterjohn’s study of hummingbirds.

Science Triumphs over the Challenge 

of Administrative Changes

In late 1988, John Tautin became the sixth BBL chief. 

Tautin, a bander and a career employee with the USFWS 

Office of Migratory Bird Management (MBMO), had worked 

as a biologist at the BBL during the mid-1970s. During his 

tenure, which lasted until 2002, the BBL faced difficult administrative challenges following its transfer from the USFWS to 

the newly created National Biological Survey (later Service; 

NBS) in 1993 and later to the U.S. Geological Survey in 

October 1996. Fortunately, during these transfers the BBL 

remained at Patuxent, where its close ties with research scientists and the MBMO helped ensure that it would continue to 

receive sufficient resources to remain functional.

John Tautin, sixth chief of the Bird Banding Laboratory, Laurel, MD. 2009. Photo 

by Tara Dodge, Purple Martin Conservation Association.
Migratory Bird Research, Monitoring, and Management

The Bird Banding Laboratory: Support for and Collaboration with Research at Patuxent 49

Kathy Klimkiewicz capturing white-breasted nuthatch with color-coded band, 

Patuxent Research Refuge, Laurel, MD, 1977. Photo by Matthew C. Perry, U.S. 

Fish and Wildlife Service.

The importance of the BBL to research at Patuxent, and 

indeed to scientists across North America, was underscored in 

an extensive report (Buckley and others, 1998) by an external 

review panel commissioned by the NBS.

The review panel’s report added impetus to ongoing 

efforts by the BBL to make the banding program more scientific. These efforts included re-engineering the BBL’s database 

and computer operations, developing software for banders to 

manage and report banding data, designing a recapture/resighting database, and implementing a toll-free telephone number 

that people could call to report bird bands.

The internal efforts made by the BBL to improve the 

management of millions of banding records have typically 

gone unheralded, but their importance to Patuxent scientists 

and the broader ornithological community cannot be overstated. For example, banders commonly replace bands on 

long-lived birds when they recapture them. The bird then has 

two, if not more, unique band numbers assigned to it, causing 

a record-keeping problem. Over the years, without direction or 

fanfare, BBL biologists, clerks, and computer staff developed 

ever better procedures for processing replaced bands, enabling 

scientists to maintain continuous records of the birds. Without 

these procedures, tracking the remarkable life of 62-yearold Wisdom, an albatross originally banded by Patuxent’s 

Chandler Robbins in 1956 and subsequently rebanded several 

times, would not have been possible.

Among the BBL’s efforts to improve operations, the tollfree number was a particularly important and successful development. In a late 1980s study, Patuxent scientists (Nichols and 

others, 1991) had determined that only 32 percent of hunters 

who killed a banded mallard actually reported the band. This 

low rate was inadequate to supply input to the data-hungry 

analytical models and adaptive management principles being 

applied in an effort to develop a more scientific approach to 

setting hunting regulations. Providing hunters with a convenient toll-free number to call for band reporting was the ideal 

solution to the need for more and better band-recovery data. 

The availability of the toll-free number doubled the reporting 

rate in only a few years.

During all of these operational developments, the BBL 

directly supported many individual Patuxent research projects 

(for example, Spendelow and others, 1995) and strengthened 

ties with Patuxent scientists. Some of these scientists were 

world leaders in developing ever more sophisticated models 

for analyzing banding and other data, while also developing 

new approaches to science-based decision making. Patuxent 

scientists Byron (Ken) Williams, James Nichols, and Michael 

Conroy cite many examples of their work in the monumental publication “Analysis and Management of Animal 

Populations” (Williams and others, 2002). The BBL helped 

by publicizing the new analytical models, participating in 

international technical conferences held to advance the models 

(Tautin, 1993; Tautin and others, 1999), organizing analytical 

workshops at ornithological meetings, and otherwise encouraging bird banders to use these powerful new tools.

Tautin retired from Federal service in late 2002. Succeeding BBL chiefs Monica Tomosy (2003) and Bruce Peterjohn 

(2008) and their staff continued the BBL’s support of research 

at Patuxent and across North America. After completing 

the initial re-engineering effort at the BBL, they expanded 

Web-based procedures that improved data collection and 

distribution; developed Bandit software, which improved the 

efficiency of submitting banding data for both the banders and 

the BBL; and developed Web-based band reporting procedures 

that cut costs and facilitated bird-band reporting by the public. 

The BBL also modernized permit policies and expanded support for bird banding in Latin America. And, as it had always 

done, during Tomosy and Peterjohn’s tenures, the BBL continued to work with scientists from Patuxent and elsewhere to 

develop and apply advanced technology for bird studies, most 

notably the use of geolocator data loggers, which revolutionized studies of migratory songbirds in 2007 (Stutchbury and 

others, 2009).
50 The History of Patuxent: America’s Wildlife Research Story

The Patuxent Wildlife Research Center 

Looks Ahead

The transfer of the bird banding office to PRR in 1942 

marked the beginning of a highly successful and mutually beneficial collaboration with research and management functions 

colocated there. So long as the BBL and Patuxent remain viable and continue to coordinate work, it is reasonable to assume 

that this remarkable 70-year legacy will continue. Maintaining 

this relationship is desirable because, as Paul Bartsch noted 

when bird banding first began in North America, “There are 

still many unsolved problems about bird life....”

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Switzerland, Birkhauser Verlag, p. 185–196.

Tautin, John, 2005, Frederick C. Lincoln and the formation of 

the North American bird banding program, in Ralph, C.J., 

and. Rich, T.D., eds., Bird conservation implementation 

and integration in the Americas: Proceedings of the Third 

International Partners in Flight Conference, Asilomar, CA, 

March 20–24, 2002, U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station, General 

Technical Report GTR–PSW–191, p. 813–814. [Also available at http://www.fs.fed.us/psw/publications/documents/

psw_gtr191/.]

Tautin, John, 2008, A history of the Bird Banding Laboratory—1920–2002, in Jackson, J.A.. Davis, W.E ., Jr., and 

Tautin, John, eds., Bird banding in North America—The 

first 100 years: Cambridge, MA, Memoirs of the Nuttall 

Ornithological Club, no. 15, p. 65–91.

Tautin, John, Metras, Lucie, and Smith, Graham, 1999, Largescale studies of marked birds in North America, in Baillie, 

S.R., and North, P.M., eds., Large-scale studies of marked 

birds: Bird Study, no. 46, suppl. 1, p. S271–S278. [Also 

available at http://dx.doi.org/10.1080/00063659909477254.]

Terres, J.K., 1947, Big brother to the waterfowl: Audubon 

Magazine, v. 49, no. 3, p. 150–158.

The Washington Post, 1967, For the birds: The Washington 

Post, January 12, 1967, p. F2.

U.S. Fish and Wildlife Service, 1972, Population ecology of 

migratory birds: Washington, D.C., U.S. Fish and Wildlife 

Service, Wildlife Research Report 2, 278 p.

Wetmore, A.C., 1915, Mortality among waterfowl around 

Great Salt Lake, Utah: Washington, D.C., Bulletin of the 

U.S. Department of Agriculture, no. 217, 10 p. [Also available at http://dx.doi.org/10.5962/bhl.title.108397.]

Williams, B.K., Nichols, J.D., and Conroy, M.J., 2002, Analysis and management of animal populations (1st ed.): New 

York, Academic Press, 817 p.
52 The History of Patuxent: America’s Wildlife Research Story

G. Michael Haramis banding a male canvasback in Chesapeake Bay, 1978. 

Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.
Migratory Bird Research, Monitoring, and Management

Patuxent’s Role in the Development of the North American 

Breeding Bird Survey

John R. Sauer

The North American Breeding Bird Survey (BBS) is a 

roadside survey of the breeding birds of North America. The 

BBS provides data from the contiguous United States, Alaska, 

southern and central Canada, and northern Mexico. Begun in 

1966 by Chandler (Chan) S. Robbins at the U.S. Geological 

Survey (USGS) Patuxent Wildlife Research Center (Patuxent), 

and now jointly managed by Patuxent, the Canadian Wildlife 

Service, and the Mexican Commission for the Knowledge and 

Use of Biodiversity, the survey is conducted primarily in June 

along more than 5,000 roadside survey routes that are surveyed once each year. Volunteer observers drive the 39.4-kilometer (24.5-mile [mi]) routes, stopping approximately every 

800 meters (m) (0.5 mi) to conduct fifty 3-minute point counts 

during which they record all the birds heard or seen within a 

400-m (0.25-mi) radius of the counting location. Observers 

submit their data for each stop along their routes to the BBS 

offices in their respective countries, after which the information is made available to the public.

The BBS is unique in its temporal and geographic scale, 

and it is often the only source of information for geographic 

studies of important scientific issues such as the effects 

of climate change, disease, and land-use change on North 

American bird populations. Wildlife researchers and managers rely on the survey as the authoritative source of information on population change for more than 400 species of North 

American birds. It was the primary source of data for the State 

of the Birds Report (North American Bird Conservation Initiative, 2009), a publicly accessible summary of the “big picture” 

of population change and conservation of North American 

birds. Nevertheless, even after more than 45 years successfully providing population change data, Patuxent researchers 

are continuing their efforts to strengthen the BBS and similar 

surveys. Keeping a survey such as the BBS current in terms of 

field methods, data management, and analyses is a formidable 

task, and Patuxent has devoted substantial resources toward all 

of these activities throughout much of its existence. This chapter describes some of the themes and approaches to the design 

and analysis of roadside bird surveys that have been used at 

Patuxent, where the BBS and related surveys conducted by the 

U.S. Fish and Wildlife Service (USFWS) for mourning doves 

(Zenaida macroura) (the Call-Count Survey [CCS]; Sauer and 

K.A. Smith and J. Rensel. Breeding Bird Survey volunteers, along historic 

intercontinental railroad grade on the Peplin Mountain, UY (Utah Breeding Bird 

Survey route 85251). Photo by U.S. Fish and Wildlife Service.

others, 2010) and American woodcock (Scolopax minor) (the 

Singing-Ground Survey [SGS]; Sauer and others, 2008) have 

been the focus of research activity since the 1940s. 

In this chapter, the term “Patuxent” is used in the “greater 

Patuxent” sense that Jim Kushlan used during his tenure as 

Patuxent’s director—that is, the historical components that 

have been merged and divided over the years to become the 

current-day Patuxent Wildlife Research Center, as well as the 

colocated USFWS and other groups that once were part of 

entities such as the Migratory Bird Populations Station.

Background of the Breeding Bird 

Survey

The USFWS had a long history of bird population 

research before the initiation of the BBS. Roadside surveys 

of singing grounds of American woodcock were pioneered by 

Mendall and Aldous (1943), and became a standard approach 
54 The History of Patuxent: America’s Wildlife Research Story

for monitoring the species. Sheldon (1953) conducted studies 

to address the number, duration, and protocols for a stop-based 

roadside woodcock survey, and Kozicky and others (1954) 

conducted a statistical review of the approach, recommending random route locations. Chan Robbins helped analyze and 

summarize woodcock and mourning dove surveys during the 

1950s, and participated in the preparation of status reports 

used in setting harvest regulations for these species. Although 

Chan had a great deal of experience with alternative bird 

counting approaches such as atlases, breeding bird censuses, 

Christmas Bird Counts (CBC), and roving censuses, he realized that the roadside survey had advantages over the alternatives as an efficient and relatively consistent way of collecting 

data over large areas. The method also had the advantage of 

having undergone a substantial evolution in approach and 

several methodological reviews while the USFWS was implementing the woodcock and dove surveys.

The critical difference between a nongame survey and 

the dove and woodcock surveys was that states were willing to 

devote resources to ensure adequate monitoring of harvested 

species, but no resources were available for nongame species. 

Consequently, when considering how to implement a North 

American breeding bird survey, Chan could not rely on the 

existing network of State personnel to conduct the counts. 

Fortunately, his birding activities provided him with a unique 

connection to the nationwide pool of birdwatchers. Chan was 

a major figure in birdwatching and, through State and regional 

bird clubs, the National Audubon Society, and a wide array of 

friends and colleagues throughout the continent, he envisioned 

staffing a survey that would utilize volunteers in the same 

way that the CBC had, but that would also have the rigor of 

the USFWS roadside surveys. Chan described his pioneering activities in developing the BBS in several presentations 

and publications (for example, Robbins and others, 1986; 

C.S. Robbins, U.S. Geological Survey, oral commun., 2006; 

Robbins, 2016). The reader is referred to these sources for 

Chan’s first-hand account of his use of the environmental 

awareness spawned by Rachel Carson’s work to establish 

the need for a nationwide breeding bird survey (see also 

Sauer, 2008).

Tending to the Survey: Research and 

Management of a Complex Survey

Chan Robbins wanted the BBS to be relevant, and recognized from the start that relevance would require (1) designing a survey that would provide credible information; (2) 

implementing the survey efficiently in terms of the logistics of 

recruiting the observers and providing support in the form of 

information (data forms, maps) and communications (a laborintensive task in the 1960s); (3) managing data (also very 

labor intensive); and (4) analyzing and effectively presenting 

the results. These needs are reflected in Chan’s early requests 

for volunteers (Robbins, 1965b) and his prompt summary of 

the data (Robbins, 1965a). Because availability of and access 

to results as well as timely feedback to observers are critical 

aspects of a successful survey, Chan presented the summarized 

results on maps to facilitate the public’s appreciation of the 

data (fig. 1; Robbins, 1965a).

The scope and goals of the BBS are extremely ambitious, 

and constant research and innovation are needed to keep pace 

with technological advances and maintain the credibility of 

the survey. Research associated with the survey has been a 

focus of field and statistical work at Patuxent over the past 

45 years. The sections below summarize some of this research 

and describe how it has enhanced the value of the survey. 

They are organized in parallel with the essential elements of 

a successful survey listed above, but focus particularly on 

Figure 1. Eastern bluebird (Sialia sialis) counts for Maryland from the 1965 

Breeding Bird Survey test run. (From Robbins, 1965a)
Migratory Bird Research, Monitoring, and Management

Patuxent’s Role in the Development of the North American Breeding Bird Survey 55

features 2 and 4 (survey implementation and communication 

of results), both of which are traditional functions of research 

that have been an important component of Patuxent for the 

duration of the survey.

Survey Design

Chan designed the survey to be consistent with the 

general approaches used by the CCS and SGS. As both of 

these surveys were used by management and had been tested 

through years of critical review and methods development, 

they were a good model for a logistically feasible survey that 

provided relevant data. Chan also conducted a variety of methodological studies in 1965 to evaluate specific aspects of the 

design, such as duration of counts and number of stops along 

the roadside routes (Robbins and others, 1986). From the 

start, however, Patuxent researchers criticized two important 

aspects of the survey. First, roadsides constitute an incomplete 

framework for sampling, as off-road habitats are not covered. 

Second, no observers count all the birds on a BBS route, and 

the proportion of birds missed in counting varies by species, 

observer, environmental conditions, date, time of day, and 

many other variables. Quantitative researchers at Patuxent in 

the 1960s were particularly critical of the BBS design, and 

vigorous arguments occurred about the need to conduct offroad counts and to collect additional data to control for variations in rates of bird detection (Charles Henny, U.S. Fish and 

Wildlife Service, oral commun., 1965). These issues have been 

the focus of much research at Patuxent over the past 40 years.

The question of whether the BBS needs to incorporate 

methods that allow estimation of rates of bird detection was, 

and still is, particularly controversial at Patuxent. Detectability 

estimation from count-based surveys has been a productive 

research area for Patuxent investigators, and many current and 

former Patuxent staff members have made important contributions in this area; all of the methods considered as possible approaches for adding detection rates to the BBS have 

been the subject of Patuxent studies. Patuxent alumni David 

Anderson and Kenneth Burnham, along with many students, 

have promoted line transect and capture-recapture methods for 

estimating detection rates of birds and other taxa.

At Patuxent, James Nichols and colleagues pioneered 

the use of capture-recapture and other approaches for analyzing count data to estimate species occupancy, abundance, and 

species richness. Andy Royle and colleagues described and 

implemented innovative ways of estimating detection rates 

from replicate surveys. William Link, William Kendall, and 

others addressed the question of detectability from a different 

perspective, considering it to be a feature of known covariates 

(such as the observer running the route), and modeling and 

controlling for these covariates in the analysis. Other quantitative ecologists, notably Ted Simons, Kenneth Pollock, and 

colleagues at North Carolina State University (Raleigh), have 

continued method development and conducted field trials to 

implement approaches for estimating detection rates. Finally, 

in his dual role as State BBS coordinator in Mississippi and 

Patuxent researcher, Daniel Twedt has implemented a pilot 

project to test the applicability of some of the field methods 

for estimating detectability along routes established in the Gulf 

Coast Network of national parks. 

Most of these studies have included enthusiastic participation by field-oriented researchers and BBS coordinators, 

including (among many others) Patuxent biologists Chan 

Robbins, Deanna Dawson, Barbara Dowell, Daniel Boone, 

Danny Bystrak, Sam Droege, Bruce Peterjohn, Keith Pardieck, Jane Fallon, and David Ziolkowski. The volunteer BBS 

observers have also been more than willing to donate their 

time to participate in studies that use BBS routes as sample 

units, permitting regional analysis. This involvement of a large 

number of Patuxent staff members and volunteers is a model 

for collaborative science.

Evaluation of the consequences of the roadside nature of 

counts has also invoked the collaborative spirit of Patuxent 

staff members, most notably in a U.S. Environmental Protection Agency-funded study, in which data were collected both 

on survey routes and on nearby off-road routes. This study 

documented differences in species abundance on and off roads 

(Sauer and others, 2013). Another approach to addressing this 

question over the years has been to evaluate habitat differences 

between on- and off-road routes, first from aerial photographs 

(Keller and Scallan, 1999), then from interpreted Landsat data 

(National Land Cover Data [NLCD]) (Vogelmann and others, 

2001) (Sauer and others, 2013; fig. 2).

EXPLANATION

Off road

On road

WaterLow residentialHigh residentialCommercialBare rock, sandBarren

Habitat

12

10

8

6

4

2

0

Percent

Figure 2. Percentages of six habitats near roads (at sampling 

sites within 400 meters [0.25 miles] of Breeding Bird Survey 

routes) and off roads (at sampling sites more than 400 meters from 

roads) in a study conducted in Maryland. (Data from Keller and 

Scallan, 1999; Sauer and others, 2013)
56 The History of Patuxent: America’s Wildlife Research Story

NLCD data provide excellent opportunities to evaluate habitats (fig. 3); several investigators have used them to 

assess whether habitats differ between on- and off-road routes 

(for example, Veech and others, 2012), or even to assess 

differences in rates of change in habitats between on- and 

off-road routes (Hanan, 2009). These studies have not shown 

major differences in habitats or rates of change in habitats 

between on- and off-road routes, although they have revealed 

that some habitats appear to be found more frequently near 

(for example, residential housing) or away from (for example, 

water) roads.

Survey Analysis and Presentation

Several themes emerge with respect to the history of the 

BBS. The first is that improvements in BBS analysis commonly were made possible by advances in computational technology. Early on in the BBS program, Patuxent’s computers 

were not adequate to conduct analyses. Enormous amounts of 

time were spent trying to develop methods that could be used 

with the available computers, and the methods that ultimately 

were used to summarize BBS data typically were only approximations of the desired estimation. This limitation was more 

Figure 3. Severna Park, MD, Breeding Bird Survey route path (buffered at 400 meters [0.25 miles]) superimposed 

on National Land Cover Database (Vogelmann and others, 2001). (From U.S. Geological Survey, n.d.; map metadata 

accessed March 25, 2015, at http://www.mbr-pwrc.usgs.gov/bbs/trend/rtehtm13a_nlcd.html)
Migratory Bird Research, Monitoring, and Management

Patuxent’s Role in the Development of the North American Breeding Bird Survey 57

than just a computer issue, as new and increased computing 

capabilities expanded the space for and generated statistical 

innovation. This was clearly the case in BBS analyses.

A second theme is that innovation in methods at Patuxent has always been a collaborative effort, facilitated by the 

presence of mathematical statisticians, statistician/programmers, and biologists, all of whom work together to adapt 

existing computational resources to research needs, develop 

new approaches to analysis that can fully use new technology, 

and track emerging technologies for use in BBS analyses. This 

collaboration has been particularly important in terms of the 

deeper statistical aspects of estimation of population change, 

and Patuxent has been fortunate that a mathematical statistician with a focus on count surveys has been directly involved 

in analyzing BBS data. This involvement has paved the way 

to innovations such as estimating equations and hierarchical 

models, and has provided the expertise needed to apply the 

computer-intensive Bayesian statistical approaches that represent the current analysis paradigm.

The third theme is long-term participation by scientists. 

Consistent support for the program has led to great institutional memory and long-term stewardship of the survey. Chan 

Robbins has been present from the start; Danny Bystrak, Sam 

Droege, and Bruce Peterjohn are all former BBS coordinators 

working at Patuxent and are still active in the program, and 

collectively Paul Geissler, Bill Link, and I (John Sauer) have 

participated in the analysis of BBS data through 30 years. 

Consequently, data analysts have the great advantage of being 

able to talk to the people who actually designed the survey, 

managed the data, and conducted earlier analyses.

Three Analytical Approaches

Analysis of BBS data is difficult because (1) the survey 

has a very large geographic scope; (2) survey routes vary 

greatly in consistency of coverage within and among regions; 

(3) the counting abilities of different observers, even those 

judged to be competent birders, can differ greatly; and (4) 

modeling change through time is fundamentally controversial, 

even without these other factors. Consequently, all serious 

analyses of these data attempt to address these four characteristics of BBS data analysis, and many methods have been 

developed to control and model this “unruly” dataset. Moreover, many investigators download BBS data and conduct 

summary analyses that ignore one or more of these inherent 

characteristics of the dataset. Evaluating these analyses and, if 

necessary, controlling for them has been an ongoing concern 

for Patuxent scientists.

BBS analysis conducted at Patuxent during the period 

1966–2013 can generally be placed into one of three “paradigms,” each of which takes an alternative approach to accommodating these concerns by using statistical methods and 

computing technologies available at the time they were used. 

Placed in temporal order, the paradigms are (1) fairly simple 

summary analyses that relied on estimating regional change 

between adjacent years as ratios of comparable counts on 

routes and portraying them as scaled changes from some base 

year; (2) route-regression approaches, in which route-specific 

trends are used as replicates for estimating change; and (3) 

hierarchical models that use Bayesian methods to fit log-linear 

models with year effects.

Base Year Methods

Base year methods were used to analyze data from 

roadside surveys for American woodcock and mourning dove 

well before the initiation of the BBS, and are described in the 

scientific reports that provided summary results to managers (for example, Robbins, 1960; Kiel, 1960). The methods 

described in these reports show the essential components of a 

regional analysis. Within a region, computation of estimated 

change between adjacent years was estimated by using routes 

surveyed by the same observer, and the composite change 

over a longer interval was determined by multiplying a series 

of yearly change estimates by an estimated mean count in 

a base year. These indexes of change from the base year 

described an estimated composite time series for the region. 

Change for groups of regions was calculated by using an areaweighted average of the indexes from the component regions 

(Kiel, 1960).

Early summaries of BBS data show these general ideas, 

but also show a variety of alternative summaries as Chan 

and his colleagues explored the possibilities of summarizing 

North American bird population change (for example, Robbins and Van Velzen, 1969, 1974). Unfortunately, analysis of 

BBS data, which included data from more than 500 species of 

North American birds collected on thousands of survey routes 

distributed over both the United States and southern Canada 

(fig. 4), proved to be very challenging. Many species were 

encountered only infrequently on routes, observers tended to 

differ greatly in quality of information, not all routes were 

surveyed, and the expansion of the survey into new regions 

resulted in data that were very unequally distributed in space 

and time. Analysts were greatly constrained in the types of 

analyses that could be conducted, and cost was typically an 

issue, limiting the ability to apply complicated linear models. 

Computing proportional changes on comparable routes from 

a base year was relatively simple and could be readily implemented for BBS data.

Route Regression Approaches

Geissler and Noon (1981) provide a comprehensive 

summary of the analysis of the BBS through the 1970s. They 

acknowledge the need to control for differing routes used in 

change estimation, but identify several statistical concerns 

associated with the base year approach of multiplying mean 

counts from some initial year by yearly changes based on 
58 The History of Patuxent: America’s Wildlife Research Story

Figure 4. North American Breeding Bird Survey route locations. (From Sauer and others, 2013; note limited density of 

locations in northern and western regions; map metadata accessed March 25, 2015, at http://www.mbr-pwrc.usgs.gov/bbs/

geographic_information/GIS_shapefiles_2013.html)

comparable routes. They instead suggest a “route regression” 

analysis, in which change is estimated by using regression 

analysis (log counts as a function of years) on individual 

routes, and then combined in a weighted average to form a 

regional composite estimate of change. The advantage of this 

approach is that observer differences can be controlled for in 

the analysis by including observer information as a covariate. 

Route regression methods were implemented for the survey 

and used in the 15-year summary of the BBS (Robbins and 

others, 1986), an important summary of the survey. Paul 

Geissler, a key figure in its development, did an admirable job 

of developing a robust analysis that could be applied to almost 

any BBS dataset.

The route regression method, with several modifications, was used as the primary BBS analysis method from 

1986 to 2008. Like the base year method, route regression 

analyses could be implemented with relatively limited computer resources. It was a robust approach in that it could be 

implemented for almost any dataset, no matter how unbalanced with respect to patterns of years when routes were 

surveyed. Unfortunately, this adaptability had a cost in terms 

of limited capability for inference, and aspects such as the 

precision weightings that were criticized as being extemporaneous (Sauer and Link, 2011). With this complicated weighted 

average, no overall model could form a framework for estimation; variances needed to be calculated through bootstrapping, 

a tedious nonparametric procedure. Route regression produced 

a summary of interval-specific trend, but many people wanted 

more information—at least a graph showing population indices by year. Sauer and Geissler (1990) suggested an approach 

for estimating composite yearly indices of abundance that 

summarized the pattern around the trend line, but estimating 

variances of these annual indices was not possible.

Paul Geissler weathered a great deal of criticism before 

the route regression method was accepted, and it underwent 

periodic review and modification throughout the time of its 
Migratory Bird Research, Monitoring, and Management

Patuxent’s Role in the Development of the North American Breeding Bird Survey 59

use. Concerns about estimation of change on routes done by 

using simple regression on log counts was addressed in 1994, 

when Link and Sauer (1994) suggested using estimating equations to estimate trend on routes. However, the limited nature 

of the trend summaries, and the advent of methods that permitted comprehensive summaries with variances from the data, 

ultimately led to the replacement in 2008 of the route regression method with a hierarchical model.

Hierarchical Models

In 2002, Link and Sauer (2002) suggested the use of a 

log-linear hierarchical model for analysis of BBS data. Hierarchical models are a flexible means of modeling complex, 

multiscale longitudinal surveys such as the BBS. Attributes 

can be estimated at different scales (for example, routes, strata, 

continent-wide); the repeated nature of counts within survey 

routes can be modeled; nuisance factors such as differences 

in counting ability among observers and observer start-up 

effects can be controlled for; and year effects can be treated 

as random and estimated even when some years are poorly 

sampled (again, a common issue in the BBS). Most important, 

the model can be fit by using Markov chain Monte Carlo, an 

extremely computer-intensive method that became accessible 

to the scientific community when the software program WinBUGS (Lunn and others, 2000) was released in 1989. These 

methods require a Bayesian approach to statistics, in which all 

quantities are random and, rather than providing estimates of 

unknown fixed parameters, the goal of inference is to estimate 

the distributions of unknown (but variable) quantities of interest. Bayesian methods have an appealing conceptual simplicity and avoid the nuanced discussions that commonly afflict 

standard (non-Bayesian, or “Frequentist”) statistical inference; 

they also have the great practical advantage of providing the 

only way to develop a comprehensive statistical framework for 

estimating population change from BBS data. 

Bill Link became interested in these methods when he 

was developing approaches for summarizing collections of 

species trends (that is, how many species are increasing in 

population), and it became evident that Bayesian methods 

were a natural approach for estimating BBS and other data. 

He gradually became an important proponent of the use of 

these methods in ecological statistics (for example, Link and 

Barker, 2010).

Sauer and Link (2011) published a comprehensive comparative analysis of population change using these hierarchical 

models in 2011, and routinely continue to provide hierarchical 

model results to users. One great advantage of hierarchical 

models is their extreme flexibility. They provide a basis for an 

infinite number of elaborations, and users can associate attributes with population relative abundance and change at any 

scale of interest. They also can include submodels to accommodate observational components such as detectability.

Maps of Breeding Bird Survey Data

The benefits of the visual display of BBS data have long 

been obvious. Chan Robbins (1965a) made simple maps by 

writing numbers of birds encountered on routes in Maryland 

from the 1965 test survey (fig. 1); Danny Bystrak qualitatively 

estimated contour lines for maps in a summary of the BBS’s 

first 15 years (Robbins and others, 1986) and other publications. By 1995, Patuxent was producing contour maps from 

surfaces based on Kriging and other surface modeling procedures (Sauer and others, 1995). Currently (2016), inversedistance maps of both trend and abundance are made for more 

than 420 bird species (fig. 5). More sophisticated approaches 

such as hierarchical models have been implemented for 

selected species, but are not routinely applied to BBS data 

(Thogmartin and others, 2004).

Figure 5. A, Relative abundance (summer distribution), 2006–10, 

and B, population change (trend) of Eastern bluebirds (Sialia 

sialis) in the 1966–2010 Breeding Bird Survey (BBS) analysis. 

(From Sauer and others, 2011; accessed February 16, 2011, 

at A, http://www.mbr-pwrc.usgs.gov/bbs/ra2010/ra7660.htm and 

B, http://mbr-pwrc.usgs.gov/bbs/tr2010/tr07660.htm; gray areas 

are regions outside the BBS area)
60 The History of Patuxent: America’s Wildlife Research Story

Internet-Based Summaries

In 1997, Patuxent began providing comprehensive summaries of BBS data to users on the World Wide Web (WWW) 

(Sauer and others, 1997). Jim Hines and I had been developing a stand-alone, PC (personal computer) -based program for 

summary and display of population trends, annual indices, and 

abundance and trend maps that we called program VUBBS. 

The material we had been producing was easily converted 

to the HyperText Markup Language (html) format that is 

still (2016) a primary means of displaying WWW content on 

browsers. Many of the results were prepackaged; we conducted the analysis, reviewed the results for consistency and 

correctness, and then provided interactive lists from which 

users could select species data for display. Because the results 

are served from a computer at Patuxent, we had great flexibility to develop new summaries by means of Perl scripts and 

other programs that allowed users to run programs on Patuxent’s computers. In this way, users could estimate population 

trends interactively for any species using predefined regions. 

These online summary results are revised annually, are available to any user, and have proven to be effective tools for bird 

conservation (figs. 6 and 7).

Figure 6. Screen capture of the home page of the North American Breeding Bird Survey results and analysis Web site, 1966–2010. 

(From Sauer and others, 2011)
Migratory Bird Research, Monitoring, and Management

Patuxent’s Role in the Development of the North American Breeding Bird Survey 61

Figure 7. Screen capture of Web site showing an example of the results obtained by using the interactive program for 

summarizing population change from North American Breeding Bird Survey data (http://www.mbr-pwrc.usgs.gov/bbs/trend/

tf11.html, accessed February 16, 2011). The program is shown in the left and center columns; the right column shows a results 

summary for Common Loons (Gavia immer) in Alberta, Canada.
62 The History of Patuxent: America’s Wildlife Research Story

A “Living” Survey (Past, Present, and 

Future)

The BBS, like any survey, can never be considered 

a finished product, but must be subject to modification to 

incorporate new ideas and address newly discovered (or even 

long-term) deficiencies. Patuxent researchers have focused on 

improving the analysis of this important survey, conducting 

field studies on the process of counting birds (for example, 

Keller and Fuller, 1995), and evaluating the consequences 

of detectability and roadside survey constraints. In addition, 

Patuxent has made the survey and analyses increasingly accessible to the scientific community through computer programs 

and technical support. Many researchers use BBS data, and 

their analyses often generate new ideas and raise (or quell) 

concerns about the survey. Making the survey analytical 

results and tools available facilitates that work. The interactive analysis program on the Breeding Bird Survey Web 

site (http://www.mbr-pwrc.usgs.gov/bbs/bbs.html, accessed 

February 16, 2011), for example, allows users to select data 

by region and period for analysis. This interaction between the 

organization that conducts the survey and the community that 

uses the survey data is critical for the long-term sustainability 

of the survey, as it maintains a focus on ascertaining and meeting user needs.

Patuxent has long taken a leadership role in summarizing this important survey. The key to the survey’s success is 

constant revision and research input into the “routine” yearly 

summaries of the data. Another key component of this success 

is the mutual respect and collaborative research skills of the 

BBS staff members, ranging from ornithologists, who inform 

the analysis with natural history and taxonomic information; to 

computer programmers, who provide the programming skills 

and Internet expertise to allow implementation of analysis 

and summary programs; to mathematical statisticians, who 

authoritatively navigate the increasingly complicated methods 

now employed for BBS data analysis. Although administrators 

may, at times, underestimate the value of statistical analysis 

in ecological research and relegate statisticians to a supporting role, such a philosophy could undermine the success of a 

complex and evolving survey such as the BBS. BBS researchers have been fortunate over the years that Patuxent’s administrators have recognized that the effective running and maintenance of the survey requires a collaborative partnership.

References Cited

Geissler, P.H., and Noon, B.R., 1981, Estimates of avian 

population trends from the North American Breeding Bird 

Survey, in Ralph, C.J., and. Scott J.M., eds., Estimating 

numbers of terrestrial birds: Lawrence, KS, Studies in Avian 

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ecological applications: New York, Academic Press, 338 p.

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Migratory Bird Research, Monitoring, and Management

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Robbins, C.S., 1965a, Fifty thousand birds recorded on Breeding Bird Survey: Maryland Birdlife, v. 21, no. 3, p. 73–79. 

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in Maryland this summer: Maryland Birdlife, v. 21, 

no. 2, p. 48–49. [Also available at https://sora.unm.edu/

node/132782.]

Robbins, C.S., 2016, Early avian studies at Patuxent, in Perry, 

M.C., ed., The history of Patuxent—America’s wildlife 

research story: U.S. Geological Survey Circular 1422, 

p. 13–24. [Also available at https://doi.org/10.3133/cir1422.

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Breeding Bird Survey—Its first fifteen years, 1965–1979: 

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gov/unnumbered/5230189/report.pdf.]

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no. 124, 107 p.

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64 The History of Patuxent: America’s Wildlife Research Story

Female killdeer guarding eggs at Patuxent Research Refuge, Laurel, MD, 2007. Photo by 

Matthew C. Perry, U.S. Geological Survey.
Migratory Bird Research, Monitoring, and Management

The Migratory Bird and Habitat Research Laboratory and 

the Accelerated Research Program

By Richard A. Coon

The Patuxent Wildlife Research Center (Patuxent) housed two important programs that were not 

supervised through the office of the Director of 

Patuxent during the 1960s and 1970s. Although they 

received administrative support from Patuxent, they 

were supervised from the U.S. Fish and Wildlife 

Service (USFWS) headquarters in Washington, D.C. 

One, the Migratory Bird Populations Station (MBPS), 

was established in 1961; the other, the Migratory 

Bird and Habitat Research Laboratory (MBHRL), was 

established in 1972 (Perry, 2004). This chapter briefly 

discusses MBPS and how some of its functions were 

transferred to MBHRL when this new laboratory 

was created.

Migratory Bird Populations Station

The main purpose of MBPS was to be a central location 

for the USFWS to study migratory bird population dynamics 

across political and administrative boundaries. Its responsibilities were international in scope, carried out in cooperation 

with Canada, Mexico, and the 50 States, as well as universities 

and private organizations.

Included as part of MBPS was the internationally recognized Bird Banding Laboratory, along with key staff tasked 

with collecting harvest information, analyzing population and 

production data, and helping to develop annual hunting regulations for migratory game birds. When the Gabrielson Laboratory was dedicated in 1969 as a major location for USFWS 

migratory bird programs, all MBPS personnel were moved 

there, including the Atlantic Flyway Representative position, 

which had been located in Delaware. The major computer 

system of the USFWS was then in the Bird Banding Laboratory and functioned to process and analyze the millions of 

bird banding records to estimate the abundance, survival, and 

distribution of migratory birds during their annual cycle.

Creation of the Migratory Bird and 

Habitat Research Laboratory

In July 1972, the management and research functions 

of MBPS were split and transferred to two newly organized 

entities. One was the Office of Migratory Bird Management 

(MBMO), housed at Patuxent but supervised from USFWS 

headquarters in Washington, D.C. Dr. John P. Rogers was the 

office’s first chief. The other was the newly organized MBHRL 

at Patuxent, which was added to the Division of Wildlife 

Research, with Dr. Robert I. Smith as its first director. Dr. Fant 

W. Martin became director of MBHRL when Smith was called 

to Washington, D.C., with Jerry Longcore in 1973 to work on 

the national issue of lead poisoning in waterfowl. Fant’s secretary was Marylu Lammers. Fant hired Drs. Franklin Percival 

and Stanley Anderson to supervise the Game and Non-Game 

Sections, respectively. Members of the Game Section included 

Byron (Ken) Williams, Chuck Kimball, Bob Munro, Lois 

Moyer, Richard Coon, Paul Geisler, George Haas, Jerry Longcore, Jim Nichols, Jim Hines, Tom Dwyer, Matt Perry, Mike 

Haramis, Holly Obrecht, Fran Uhler, Ralph Andrews, and 

Frank McGilvrey. Among those involved in nongame work 

were Chan Robbins, Mark Fuller, Mike Erwin, Deanna Dawson, Barbara Dowell, Elwood Martin, and Marshall Howe.

Migratory Bird Habitat and Research 

Laboratory Activities

During the 1970s, Patuxent was growing larger. Its staff 

was concentrating on contaminants research as well as its 

newest function, the Endangered Species Program, whereas 

activities such as wetland research (Wetland Ecology Section) 

were receiving less emphasis. Additionally, Patuxent increased 

the number of field stations around the country. Because of this 

shift in emphasis and an expansion of field station responsibilities, the Wetland Ecology Section was transferred to MBHRL. 
66 The History of Patuxent: America’s Wildlife Research Story

Shortly after the transfer, the long-running impoundment 

management program at Patuxent was discontinued.

MBHRL activities in the 1970s were divided between 

field research and in-house work at Patuxent. One noteworthy 

feature of work at Patuxent was the increased responsibility for analyzing migratory bird population data. Drs. Dave 

Anderson and Jim Nichols achieved international prominence 

with their sophisticated modeling techniques, which improved 

the management potential for waterfowl populations and other 

migratory birds on a large scale.

Off-site work on species of concern and species groups 

was conducted in specific geographic areas. In Maine, Tom 

Dwyer and Bill Krohn worked on the American woodcock 

(Scolopax minor), and Jerry Longcore focused on the diminishing population status of black ducks (Anas rubripes). Matt 

Perry and Mike Haramis conducted canvasback (Aythya valisineria) studies both at Patuxent and on Chesapeake Bay. In 

South Carolina and Georgia, George Haas conducted extensive 

research on mourning doves (Zenaida macroura). In many of 

these studies, radiotelemetry techniques were used widely to 

collect data that otherwise would not have been available.

MBHRL disbanded in 1981, and Patuxent absorbed its 

functions and responsibilities. Fant Martin had transferred to 

MBMO in 1980 and, after another year under interim Patuxent Director John Rogers, Jr., the lab was closed as directed by 

USFWS headquarters.

George Haas, U.S. Fish and Wildlife Service, capturing a dove in South 

Carolina, 1977. Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.

Accelerated Research Program for 

Migratory Shore and Upland Game 

Birds

Since the passage of the Migratory Bird Treaty Act in 

1918, the Federal Government and, ultimately, the USFWS, 

has been responsible for the management and study of migratory birds. One group, generally known as webless migratory 

birds, had been largely understudied, however. By the mid1960s, a growing belief existed among wildlife managers 

that this situation needed to be remedied. Consequently, State 

wildlife managers working with the USFWS acted to obtain 

congressional funding for the Accelerated Research Program 

(ARP), which focused on migratory shore and upland game 

birds, in 1967 (MacDonald and Evans, 1970).

In 1972, the ARP, under the overall direction of Fant 

Martin, became one of the programs within MBHRL at 

Patuxent. The following biologists provided oversight to 

the program by serving as contract managers: Henry (Milt) 

Reeves, 1967–68; Duncan MacDonald, 1968–71; Fant Martin, 

1971–75; Richard Coon, 1975–80; and Tom Dwyer, 1980–82.

The two primary forces behind the formation of the ARP 

were the Southeastern Association of Game and Fish Commissioners and the International Association of Game, Fish and 

Conservation Commissioners (later the International Association of Fish and Wildlife Agencies [IAFWA]). The species 

to be studied included Wilson’s snipe (Gallinago delicata), 

rails (Rallidae), American coots (Fulica americana), sandhill 

cranes (Grus americana), American woodcock, and the various doves, principally the mourning dove, and white-winged 

dove (Zenaida asiatica).

The paucity of biological information on these species 

was reducing the capability of the USFWS and the States to 

manage them as game birds (for example, setting hunting 

seasons, determining season length, establishing bag limits). 

Young woodcock banded at Patuxent Wildlife Research Center, Laurel, MD, 

by Brooke Meanley, U.S. Fish and Wildlife Service, 1979. Photo by Matthew C. 

Perry, U.S. Fish and Wildlife Service.
Migratory Bird Research, Monitoring, and Management

The Migratory Bird and Habitat Research Laboratory and the Accelerated Research Program 67

Frank Percival, U.S. Fish and Wildlife Service, recording data on September 

dove survey at Patuxent Wildlife Research Center, Laurel, MD, summer 1979. 

Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.

Their food habits, population status, migration characteristics, and general life histories would be the target of the new 

research effort. With the loss of habitats for these species 

increasing, the need for information about the population 

health, status, and distribution was becoming critical. Techniques such as radiotelemetry, cannon netting, mist netting, 

night lighting, banding, and color marking were important 

research tools. In addition to the State wildlife agencies 

that were seeking funds, many universities and cooperative 

wildlife units competed for money to support M.S. and Ph.D. 

studies. After a few years, workshops were held to present, 

publish, and disseminate tribute research results.

In July 1967, Congress initiated an annual appropriation 

of $250,000 to fund the ARP. Of this amount, $175,000 was 

to be contracted to the States to support individual research 

projects, $50,000 was retained by the USFWS for research 

on woodcock and mourning doves, and $25,000 was retained 

for program administration. The USFWS administered the 

contracts, provided oversight and review for selected projects, 

and received the final research reports. In the 16 years during 

which the program was active, 122 research projects were 

completed in 41 States (Eshmeyer and Harris, 1974).

Research by the USFWS under the ARP was conducted 

on woodcock in Maine, mainly at the Moosehorn National 

Wildlife Refuge, first by William Russell and then by William Krohn and Tom Dwyer. In South Carolina and Georgia, 

Spencer Amend was the first biologist to study mourning 

doves with ARP funding; he was followed by George Haas.

Termination of the Accelerated 

Research Program

The ARP was terminated in October 1982, when annual 

funding was discontinued because of fiscal constraints 

imposed on the USFWS. Approximately $2.5 million had been 

awarded to the States over the course of the 16-year program. 

An estimated 340 publications resulted from the ARP (Ronnie 

George, Texas Parks and Wildlife Department, written commun., 1985).

An important outgrowth of the ARP was the publication 

of “Management of Migratory Shore and Upland Game Birds 

in North America” in 1977, under the direction of the IAFWA 

(Sanderson, 1977). This book, edited by Glen C. Sanderson of 

the Illinois Natural History Survey, summarized the data and 

other information that had been collected to that point, primarily through ARP funding, about migratory shore and upland 

game birds. Additionally, it identified future actions and needs 

for these birds, including financial support, to ensure sustainable populations for the public to enjoy. The book was updated 

and reissued in 1994 (Tacha and Braun, 1994).

Importance of the Accelerated 

Research Program

A primary value of the ARP was its direct benefit to 

wildlife managers, particularly at the State level. The vast 

majority of the studies consisted of applied research that 

focused on important webless migratory game-bird species. 

In addition, because proposals for research were guided by 

the States, the studies were needs based. The ARP arguably 

enhanced our collective understanding of the biology of 

webless migratory game birds more than any other wildlife 

management program. Listed below are a few examples of the 

many outcomes and benefits that resulted from this important 

cooperative program:

1. The hunting of mourning doves was legalized in Wyoming, Nebraska, and North Dakota.

2. Hunting pressure and harvest rates were shown to have 

little adverse effect on mourning dove survival.

3. Hunting seasons on band-tailed pigeons (Columba 

fasciata) were reinstituted in Arizona, Colorado, New 

Mexico, and Utah.

4. The redefinition of harvest unit boundaries resulted in 

increased hunting opportunity for snipe and rail hunters.

5. The understanding of the timing of American coot migration was improved.
68 The History of Patuxent: America’s Wildlife Research Story

6. Subpopulations of sandhill cranes were identified.

7. Estimates of allowable harvest rates for sandhill cranes 

were improved.

8. Identification of woodcock migration routes and wintering 

locations through intense banding programs allowed for 

the development of two management units (eastern and 

western) for improved harvest management.

9. Wetland habitats preferred by rails and common snipe 

were identified.

10. Census procedures for rails were developed.

11. The interchange of knowledge, thoughts, and ideas among 

individuals working within the States, the regions, and 

various other agencies, universities, and organizations 

was facilitated.

Revitalization of the Accelerated 

Research Program

Beginning in 1986, there was renewed interest on the part 

of the States and the USFWS to revitalize the ARP with new 

funding. After a 9-year delay, $300,000 was made available 

for the program, which was renamed the Webless Migratory 

Game Bird Research Program (Dolton, 2002). Funds were set 

aside by Dr. Ronald Pulliam, then Director of the Biological 

Resources Division of the U.S. Geological Survey. This onetime funding was followed in 1996 by an annual allocation of 

$150,000 from the USFWS. Dolton (2002) of the USFWS, 

Office (now [2016] Division) of Migratory Bird Management, 

in Denver, CO, reported that in the first 6 years of the renewed 

program, 32 research projects were completed with more 

than $1.1 million of program funds. This number increases to 

approximately $4 million when the contributions of materials, 

time, and additional support made by State wildlife agencies, 

universities, and other non-USFWS sources as the research 

projects were conducted are considered.

Summary

The unique quality of a major wildlife research center 

like Patuxent is its ability to adapt to changing times, changing 

research needs, and changing budgets. As managers and directors come and go, new programs are born and older programs 

disappear. The Migratory Bird and Habitat Research Laboratory (MBHRL) and the Accelerated Research Program (ARP) 

exemplified changing times and priorities; nevertheless, the 

achievements of both while they existed left a lasting mark on 

natural-resource conservation. Since then, Patuxent-wide work 

has carried on as former MBHRL personnel, including ARP 

staff, were absorbed into other Patuxent programs. Throughout 

Normal and albino Virginia rails banded by Mike Haramis at Patuxent 

River, 1992. Photo by G. Michael Haramis, U.S. Fish and Wildlife Service.

its history, Patuxent has maintained its reputation as a worldrenowned wildlife research center—a tribute to the resiliency 

and dedication of its staff, whose extraordinary productivity 

has been sustained throughout.

References Cited

Dolton, D.D., 2002, History and administration of the Webless Migratory Game Bird Research Program, 1995–2001: 

Denver, CO, U.S. Fish and Wildlife Service, Office of 

Migratory Bird Management, 6 p., accessed March 26, 

2015, at http://central.flyways.us/sites/default/files/uploads/

Webless_Research_History_0.pdf.

Eschmeyer, P.H., and Harris, V.T., eds., 1974, Bibliography of 

research publications of the U.S. Bureau of Sport Fisheries and Wildlife, 1928–72: Washington, D.C., Bureau of 

Sport Fisheries and Wildlife, Resource Publication, no. 120, 

154 p.

MacDonald, D.D., and Evans, T.R., 1970, Accelerated 

research on migratory webless game birds: Washington, 

D.C., Wildlife Management Institute, Transactions of the 

North American Wildlife and Natural Resources Conference, v. 35, p. 149–156.

Perry, M.C., 2004, The evolution of Patuxent as a research 

refuge and a wildlife research center: Laurel, MD, U.S. 

Geological Survey Patuxent Wildlife Research Center, 

20 p., accessed March 27, 2015, at http://www.pwrc.usgs.

gov/history/cronhist/PatuxentHistory_Perry.pdf.

Sanderson, G.C., ed., 1977, Management of migratory shore 

and upland game birds in North America: Washington, 

D.C., International Association of Fish and Wildlife Agencies, 358 p.

Tacha, T.C., and Braun, C.E., eds., 1994, Migratory shore and 

upland game bird management: Washington, D.C., International Association of Fish and Wildlife Agencies, 223 p.
Migratory Bird Research, Monitoring, and Management

Patuxent’s American Black Duck Studies from 

Chesapeake Bay to Maine and Beyond

By Jerry R. Longcore

Introduction

The information in this chapter draws on published literature and unpublished reports written by staff members of the 

U.S. Geological Survey, Patuxent Wildlife Research Center 

(Patuxent), during its 75-year history. Reports by Bureau of 

Biological Survey (Biological Survey) and U.S. Fish and 

Wildlife Service (USFWS) personnel are included because 

the research entity currently known as Patuxent was formerly 

administered by these agencies. Some of the cited reports were 

prepared by USFWS scientists while they were not working 

at Patuxent. Literature resulting from work at other Federal 

and State agencies and private and academic institutions that 

influenced research at Patuxent on the American black duck 

(Anas rubripes, hereafter referred to as black duck) and that is 

essential to the discussion of black duck studies is included. 

Literature citations are selective, but include representative 

papers that cover four research topics: chemical contaminants, 

ecology, analyses of banding and survey data and population 

changes, and the now discredited hypothesis that the mallard 

(Anas platyrhynchos) could competitively exclude black ducks 

from fertile wetlands.

Background

The black duck, a sporting game duck ardently sought 

throughout its range by waterfowlers, is regaled as “the most 

sagacious, wary and wildest of all ducks” (Kortright, 1942, 

p. 164). This species has been a favorite target of coastal 

gunners along the Atlantic Flyway (Wright, 1947; Sullivan, 

2003), inland throughout the Mississippi Flyway (Bellrose and 

Chase, 1950), and throughout its range in Canada. Regulations governing hunting of waterfowl were historically nearly 

nonexistent or extremely liberal, with 107-day seasons and 

large daily bag limits of 75 birds in the 1920s. Shooting was 

allowed during spring migration, and hunters took sport in seeing how many sitting ducks could be killed with one shot, usually with 8- or 10-gage double-barreled shotguns (Day, 1949, 

p. 10). Baiting of ducks was allowed (Leopold, 1931), live 

decoys referred to as “call” ducks (Perry, 1984) were used, and 

Captive black ducks at Patuxent Wildlife Research Center, Laurel, MD, March 

1992. Photograph by Matthew C. Perry, U.S. Fish and Wildlife Service.

killing of ducks to sell in the markets of large cities occurred 

with impunity (Buckingham, 1937). The great market hunting 

areas were along the Atlantic Coast, Lower Mississippi Flyway States, and the Pacific Coast States, especially California 

(Hornaday, 1913). 

Studying the ecology of black ducks and their management was not a research priority during the early years of the 

Biological Survey, which evolved in 1896 from the Division 

of Economic Ornithology, formed by an Act of Congress in 

1886 and located in the U.S. Department of Agriculture (Perry, 

1984). Scientists at that time focused on recording the negative economic effects of avian species on agricultural crops, 

although they did publish on foods of waterfowl (McAtee, 

1913) and bird migration (Cooke, 1906). The Biological 

Survey, which was in its infancy in 1920 (Hawkins, 1984), 

started a bird-banding program headed by Frederick C. Lincoln. The Biological Survey was the forerunner of the Bureau 

of Sport Fisheries and Wildlife, later renamed the U.S. Fish 

and Wildlife Service and transferred to the Department of the 

Interior (DOI).
70 The History of Patuxent: America’s Wildlife Research Story

1930s

The Patuxent Research Refuge was established in 1936 

by Executive Order 7514 as part of the U.S. Department of 

Agriculture. In 1939, the Bureau of Fisheries and the Biological Survey were consolidated into one agency and, in 1940, it 

was transferred to DOI to form the Fish and Wildlife Service 

(FWS). In 1956, the FWS was divided into the Bureau of 

Sport Fisheries and Wildlife (BSFW) and the Bureau of Commercial Fisheries, and the FWS became the U.S. Fish and 

Wildlife Service. In 1970, the Bureau of Commercial Fisheries 

was transferred back to the Department of Commerce and the 

BSFW designation was discontinued.

The name “Patuxent Research Refuge” was changed 

to “Patuxent Wildlife Research Center” in 1956. Scientists 

during the earliest years of Patuxent Research Refuge pursued work that had been begun in the Biological Survey days, 

mainly exploring the mystery of bird migration (Cooke, 1915; 

Lincoln, 1935), that led to the concept of biological flyways of 

birds as espoused by F.C. Lincoln (Hawkins, 1984), and identifying foods of waterfowl (Cottam, 1939; Martin and Uhler, 

1939). During this time, concern for the future of diminishing 

stocks of waterfowl was acknowledged. Earlier, Cooke (1906, 

p. 10) had stated, “The principal causes of the diminished 

numbers of waterfowl have been market hunting, spring shooting, and the destruction of the breeding ground for farming 

purposes.” Waterfowlers on Chesapeake Bay during the “days 

of plenty” shot from the deadly sinkbox in the 1800s; from 

1870 to 1875, it was not uncommon for 15,000 ducks to be 

killed on Chesapeake Bay in a single day (Sullivan, 2003). 

A report about gunning on the Eastern Shore of Maryland 

described the use of corn bait and unplugged guns, the shipping of ducks to markets in Baltimore, and the use of live 

decoys, but stated that “The activities of the Biological Survey 

men have been such as to make the natives take precautions” 

(National Association of Audubon Societies, 1937).

1940s

During the next decade, Ira Gabrielson (1947) sounded a 

call to address the declining black duck population, stating that 

the “program should be accompanied by restrictions on shooting sufficient to limit kill to less than the annual number of 

ducks put on the wing.” Cottam (1948) addressed the causes 

of the waterfowl crisis as “destruction of habitat,” “subnormal 

production,” and “overshooting.” In this period, studies of 

black ducks by State biologists, especially in Massachusetts, 

were initiated. Wright (1947, p. 138–139) reported his findings on the black duck in eastern Canada in a progress report 

to the Chief Naturalist of Ducks Unlimited and concluded 

the following:

“The evidence therefore indicates that all is not well 

with the black duck of the Atlantic Flyway, and that 

the trouble is probably not to be found in the part 

of life he spends in reaching the breeding ground 

and producing the annual crop, but in the gauntlet 

of gun-fire he faces from southern Canada to the 

wintering ground and on the wintering ground. 

The gradual increase in hunting pressure together 

with the dying off of his favourite winter food, the 

eelgrass, and the reduction of winter range caused 

by the steady building up of the human population 

with its attendant demand for mosquito-free summer 

cottages along the Atlantic seaboard, has reduced 

the species to the point where it is impossible, in the 

east, to find only one duck of any kind in 14 acres 

of marsh where they were once found in sufficient 

number that they could be secured with a club.”

1950s

During this period, Stewart (1958) published distribution 

maps for breeding and wintering black duck populations, and 

Addy (1953) reported on the fall migration of the black duck. 

In the mid-1950s, the USFWS initiated a series of mid-winter 

surveys in cooperation with States in the Atlantic and Mississippi Flyways to inventory waterfowl. These mid-winter 

inventory (MWI) data indicated a total black duck population 

of 500,000 to 600,000, but this number was declining about 

2 percent annually (Serie, 1997, p. 14).

1960s

During the 1960s, an evaluation of the role of chemical 

contaminants in the decline of the black duck was initiated by 

analyzing for pesticides in eggs (Reichel and Addy, 1968) and 

wings (Heath and Prouty, 1967; Heath, 1969). Several contaminants, especially dichlorodiphenyltrichloroethane (DDT) 

and its metabolites, were detected in eggs and wings, which 

prompted experimental pen studies in the early 1970s to determine if and how DDT affected reproduction. Stewart (1962) 

analyzed 1953–59 MWI data and described waterfowl populations, including that of the black duck, in the Upper Chesapeake Bay region. Lucille Stickel edited Stewart’s 208-page 

manuscript, and several Patuxent staff members (Francis M. 

Uhler, Alexander Martin, Neil Hotchkiss, and Robert Mitchell) 

assisted in identifying foods of waterfowl sampled in Chesapeake Bay. Chuck Kaczynski and Jake Chamberlain (1968) 

reported the number of black ducks counted during aerial 

surveys in eastern Canada. John Sincock (1962) estimated the 

amounts of food consumed by waterfowl, including the black 

duck, in Back Bay, Virginia/Currituck Sound, NC.

Atlantic Flyway representatives, who were trained biologists, supported black duck research studies, surveys, and 

banding projects. In 1967, the Atlantic Flyway Council, Technical Section, created a Black Duck Committee (Serie, 2002); 

its first action was to organize a Black Duck Symposium in 
Migratory Bird Research, Monitoring, and Management

Patuxent’s American Black Duck Studies from Chesapeake Bay to Maine and Beyond 71

Chestertown, MD (Barske, 1968). C.E. Addy (1968, p. 2) provided a general review of black duck status at the symposium, 

which brought together American and Canadian biologists and 

administrators to review known information about and identify the needs of the black duck. Several Patuxent scientists 

contributed papers on topics such as harvest and population 

dynamics (Martinson and others, 1968), aerial surveys (Chamberlain, 1968), environmental pollution (Stickel, 1968), and 

control of predators and competitors (McGilvrey, 1968). Comments made in the symposium proceedings included, “...it 

seems obvious that measures need to be taken immediately 

to bring controllable kill in line with production...” (Wilder, 

1968); “We need more quantitative information about nonhunting mortality” (Loughrey, 1968); “Most Canadian biologists are of the opinion that not all available habitat is being 

used because there are not enough black ducks to occupy 

it” (Munro, 1968); and “Any rational attempt to reduce the 

legal take of black ducks should consider the situation in both 

Canada and the U.S.” (Wilder, 1968). At this time, American and Canadian personnel agreed that the harvest of black 

ducks was affecting the black duck population. This consensus 

provided a unique opportunity to implement a plan to curtail 

harvest. This opportunity, however, was not embraced and, 

in fact, was delayed for years. In addition, Johnsgard (1967) 

raised the possibility that the black duck (whose gene pool 

was smaller than that of the mallard) could eventually disappear as a distinct entity through hybridization with the mallard, 

although such a development was considered unlikely in the 

near future. This paper and other, similar reports put forward 

a speculative view that mallards could be the cause of the 

decline in the number of black ducks. Such speculation may 

have confounded black duck population studies and fostered 

controversy that delayed the confirmation of the actual causes 

of the decline for the next 30 years.

1970s

This decade brought additional surveys to document 

concentrations of polychlorinated biphenyl (PCB) and DDT 

contaminants in black duck eggs (Longcore and Mulhern, 

1973) and a survey of lead in wing bones (Stendell and others, 

1979). Experimental studies of the effects of dichlorodiphenyldichloroethylene (DDE) on the thickness of black duck 

egg shells (Longcore and others, 1971) documented extensive shell thinning in the eggs examined compared to those 

collected in 1968 (Reichel and Addy, 1968). Longcore and 

Samson (1973) reported a fourfold increase in shell cracking 

when females were allowed to incubate their own clutches. 

This finding confirmed that the productivity of some breeding females was decreasing because of the loss of eggs with 

cracked shells in nests. Negative reproductive effects caused 

by DDE persisted into the next year, even after the dosage 

was curtailed (Longcore and Stendell, 1977), adding credence 

to the hypothesis that chemicals were affecting reproduction. Monitoring of organochlorine residues and mercury in 

Jerry Longcore, U.S. Fish and Wildlife Service, checking eggs for cracked 

shells, DDE study, Patuxent Wildlife Research Center, Laurel, MD, spring 1972. 

Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.

American black duck female and brood, DDE study, Patuxent Wildlife Research 

Center, Laurel, MD, spring 1972. Photo by Matthew C. Perry, U.S. Fish and 

Wildlife Service.

black duck wings continued (Heath and Hill, 1974; White and 

Heath, 1976; White, 1979), and effects of mercury on black 

duck survival and reproduction were shown to include reduced 

egg hatchability and lower duckling survival in captive ducks 

fed 3 parts per million of methylmercury over 2 years (Finley 

and Stendell, 1978).

Geis and others (1971) analyzed data from several 

harvest surveys and concluded that hunting regulations 

affect hunting mortality rate, which in turn affects the annual 

survival rate; however, the statistical methods used in this 

study were later shown to be invalid (Anderson and Burnham, 

1976). Because nest loss of ground-nesting black ducks could 

affect the population, McGilvrey (1971) conditioned black 

duck females to elevated nest cylinders on a support post 

equipped with a predator guard. Of 169 captive-reared female 

black ducks imprinted to these cylinders and then released in 

the fall, only 39 returned to nest the next spring.

After joining the Patuxent Migratory Bird and Habitat 

Research Laboratory, which had been established in 1972, 
72 The History of Patuxent: America’s Wildlife Research Story

Reinecke (1979) reported on the important foods, growth, and 

development of juvenile Maine black ducks. Hunting mortality typically was considered to be compensatory to other forms 

of mortality (Nichols and others, 1984), but the concept of a 

threshold of additivity of hunting losses emerged as Anderson 

and Burnham (1976, p. 41) stressed that “Whatever this point 

is, it may be easy to exceed it on the breeding grounds or on 

areas where the birds may be particularly vulnerable (Jessen, 

1970). Harvest rates early in the season on adult females and 

young on breeding and staging areas could be severe.”

In 1976, with an increased commitment to developing an 

understanding of the variables affecting the black duck, Patuxent sent me to Maine to investigate the breeding ecology of the 

species. At the same time, Patuxent biologist Dr. Ronald Kirby 

was assigned to investigate aspects of wintering ecology of 

black ducks along the Atlantic Coast, focusing on Chesapeake 

Bay and New Jersey. Implications about the role of the mallard in the black duck population decline persisted as Johnsgard and DiSilvestro (1976) suggested that “....the relatively 

specialized black duck, through increased competition and 

hybridization with the much more broadly adaptable mallard, 

will continue to become an increasingly rarer [sic] component 

of the North American bird fauna.” It seemed to some of us 

field biologists studying the black duck, however, that “There 

is always an easy solution for every human problem—neat, 

plausible and wrong” (Mencken, 1917).

1980s

Black duck conservation and management during this 

decade benefited from establishment of a Black Duck Committee by the Atlantic Flyway Council, which was chaired by 

H.E. Howard Spencer, Jr. (Spencer, 1980). This committee 

compiled a Black Duck Management Plan for North America 

1980–2000 with data provided by personnel of Provincial, 

Federal, and State agencies; organizations; and private citizens. Black duck conservation benefited further from formal 

establishment of the North American Waterfowl Management 

Plan (NAWMP) (U.S. Fish and Wildlife Service, 1986) and 

from increased research, including an array of field studies by 

several Patuxent scientists. The NAWMP was signed by the 

governments of the United States and Canada in 1986 (Serie, 

1997), and the plan identified the black duck as a “species of 

international concern.” Under the plan, the Black Duck Joint 

Venture (BDJV) was formed and implemented in 1990 to 

coordinate data gathering for population surveys, banding, and 

research. A winter population goal was set at 385,000 black 

ducks. A technical committee established within the BDJV, 

composed of American and Canadian biologists, reviewed proposed survey, banding, and research projects, thereby improving the quality of data collected.

Patuxent continued its research on exposure to contaminants and their effects on black ducks. A minute amount 

(3 parts per million, dry weight) of DDE in the diet of black 

ducks caused loss of shell thickness and mass (Longcore and 

Stendell, 1982), but by 1978, the thickness of black duck 

eggshells had recovered to a pre-1946 mean (Haseltine and 

others, 1980). This discovery lessened the probability that 

chemicals were decreasing productivity and contributing to the 

population decline, but monitoring of organochlorine pesticide 

residues in black duck wings continued (Cain, 1981; Prouty 

and Bunck, 1986; Hall and others, 1989). Heinz and Haseltine (1981) documented that chromium added to the diet of 

young black ducks affected their avoidance behavior; similar effects were determined for cadmium (Heinz and others, 

1983). Differential susceptibility to lead poisoning between 

the black duck and the mallard was suggested as a possible 

cause of declines in the number of black ducks (Chasko and 

others, 1984). Rattner and others (1989) refuted the hypothesis 

that the black duck was more sensitive to lead poisoning than 

the mallard by documenting the absence of any difference in 

mortality between these species on the same lead pellet dosage 

and diet.

The effects of acidic deposition on wetland invertebrates raised concern that growth and survival of black duck 

ducklings could be negatively affected. The role of wetland 

acidification on captive black ducks was evaluated at Patuxent with constructed ponds that were experimentally acidified 

by Haramis and Chu (1987) and Rattner and others (1987), 

whose findings indicated lower invertebrate food production 

on acidic ponds and possible adverse effects on ducklings. In 

subsequent field studies, Longcore and others (2006) reported 

that black duck broods readily used low-pH wetlands with 

good survival of ducklings.

Kirby (1988) reviewed enhancement of black duck breeding habitat in the northeastern United States, and Jorde and 

others (1989) compiled information on existing tidal and nontidal wetlands of the northern Atlantic States. Results of several studies on breeding ecology and survival of black ducks 

were published by Patuxent scientists and associated students. 

Longcore and Ringelman (1980) determined variables affecting breeding densities in the Northeast and developed a black 

duck population model through use of computer simulations 

(Ringelman and Longcore, 1980). Results of telemetry used 

on breeding pairs of black ducks in Maine revealed movements and wetland selection by brood-rearing black ducks 

(Ringelman and Longcore, 1982a), survival of broods to fledging (Ringelman and Longcore, 1982b), habitat types selected 

and sizes of home ranges of males and females (Ringelman 

and others, 1982a), nest and brood attentiveness of females 

(Ringelman and others, 1982b), and survival of females 

(Ringelman and Longcore, 1983). Krementz and others (1987) 

determined sources of variation in survival and recovery rates 

in black ducks, wherein more adults than hatch-year ducks 

survived and more adult males than adult females survived. 

Survival rates were similar for young of both genders, but 

the recovery rate was greater for young males than for young 

females. Although recovery rates were time dependent, 

survival rates were not, which indicates that some variations 

in mortality caused by hunters may be compensated for by 
Migratory Bird Research, Monitoring, and Management

Patuxent’s American Black Duck Studies from Chesapeake Bay to Maine and Beyond 73

Dan Stotts and Mike Conroy, U.S. Fish and Wildlife Service, recording weight 

of black ducks, Atlantic City, NJ, 1982. Photo by Matthew C. Perry, U.S. Fish 

and Wildlife Service.

other causes. Body mass in winter was not positively related 

to annual survival (Krementz and others, 1989). In studies of 

the effects of hunting on black duck survival, Krementz and 

others (1988) reported that changes in harvest rate under different regulatory schemes resulted in direct effects (that is, an 

additive effect) on survival of some age or sex classes (such 

as adult males and juveniles). Rogers and Patterson (1984) 

reviewed black duck population status and management and 

noted that average decline in the population was approximately 1.5 percent annually in the 1970s and 1980s.

Grandy (1983) referred to management of the black duck 

as “a case of 28 years of failure in American wildlife management,” and attributed the long-term population decline to 

excessive harvest of black ducks. Nichols and others (1984) 

reviewed evidence for compensatory mortality in waterfowl 

losses, and Anderson and others (1987) advocated the use of 

experiments to understand black duck population dynamics. 

Nichols and others (1987) determined that band recovery rates 

of sympatric black ducks and mallards were similar and results 

of tests for differences in annual survival rate were equivocal. 

Conroy and Blandin (1984) identified geographic and temporal differences in band reporting rates for black ducks, but 

the optimum estimate was a constant 0.43, although this value 

may overestimate the reporting rate because some reward 

bands are not reported. Conroy and Krementz (1986) challenged the validity of inferences made by Boyd and Hyslop 

(1985) regarding effects of hunting on survival rates of black 

ducks. Conroy and others (1989b) determined mean winter 

survival rates for female black ducks along the Atlantic Coast 

as 0.73 for after-hatch-year ducks and 0.60 for hatch-year 

ducks that had a lower body mass.

Conroy and others (1988) evaluated the aerial transects 

for the MWI of black ducks and concluded that the survey 

was a useful index. Diefenbach and others (1988a) identified 

distributions of wintering populations of black ducks that had 

a stronger fidelity to coastal wintering sites than inland sites. 

Young black ducks wintered northeast of young mallards, 

but no differences in distribution patterns existed between 

adult birds (Diefenbach and others, 1988b). Longcore and 

Gibbs (1988) identified critical habitat for black ducks on the 

Maine coast during the severe winter of 1980–81, when ducks 

roosted in the lee of islands. Rusch and others (1989) summarized information on the population status and harvest of the 

black duck. Longcore and others (1987) evaluated black duckmallard interactions as noted in literature related to Maine 

and found few records, but numbers of black duck broods 

were declining substantially statewide on 36 index wetland 

areas (15,019 acres) in the relative absence of mallard broods 

(table 1).

Table 1. Numbers of black duck and mallard broods on 

36 index wetlands in Maine, 1956–86.

[Modified from Longcore and others, 1987]

Species

Years

1956–65 1966–76 1977–86

Black duck 457 328 178

Mallard 2 5 18

Ankney and others (1987) implied that the number of 

mallards in Ontario and Quebec, Canada, was increasing at 

the expense of the black duck population, whose numbers 

were declining in some parts of its range. Data to support 

this assertion were lacking, however, as noted by Conroy and 

others (1989a), who commented that no evidence existed for 

“cause and effect” for the hypothesis of “increasing mallards 

and decreasing black ducks.” Ankney and others (1989) tried 

to defend their position on the role of the mallard in the black 

duck decline. The belief that mallards could competitively 

exclude black ducks from fertile habitats, however, appeared 

to be losing support.

1990s

The second Black Duck Symposium (Kehoe, 1997) 

was held at the beginning of this decade. Serie and others 

(1997) informed on population status and harvest management strategies in the United States, and Serie and Bailey 
74 The History of Patuxent: America’s Wildlife Research Story

(1997) discussed implementation of the BDJV. Longcore and 

Ringelman (1997) reported that, although the area occupied 

by surface water increased in a 58-square-mile area in southcentral Maine, the number of pairs and broods of black ducks 

decreased from 1958–60 to 1978–80.

In a study of the effect of acid precipitation on the quality of invertebrate food eaten by the black duck, Sparling 

(1990) evaluated the effects of dietary aluminum, calcium, and 

phosphorus on the growth and survival of captive black ducks 

and mallards. Black ducks seemed more sensitive than mallards to treatments low in calcium and phosphorus and high in 

aluminum. Effects of these diets on bone and liver characteristics of these species were similar (Sparling, 1991). Frazer and 

others (1990a, 1990b) evaluated home range, movements, and 

habitat use of post-fledging black ducks in Maine and New 

Brunswick. Krementz and others (1991) documented historical changes in egg-laying date, clutch size, and nest success of 

black ducks in Chesapeake Bay and compared the productivity of the black duck to that of the mallard, which was similar 

(Krementz and others, 1992).

Black duck breeding ranges have been decreasing across 

the Bird Conservation Regions of Boreal Hardwood Transition and the Great Lakes/St. Lawrence Plain throughout the 

second half of the 20th century (Pendleton and Sauer, 1992). 

Krementz and Pendleton (1991) recorded the movements and 

survival of black duck and mallard ducklings on Chesapeake 

Bay with implanted transmitters and found no differences in 

movements between species, but black duck duckling survival 

rates were greater than mallard survival rates in 1 of 2 years. 

Longcore and others (1998) determined that mean sizes of 

Class II-III broods of black ducks (slightly less than 4 to 4.5 

ducklings per brood) equaled or exceeded those of mallards 

regardless of habitat type; moreover, black duck females with 

broods were not competitively excluded from inhabiting fertile 

wetlands in Maine. The period (late August to mid-December 

1985–87) survival rate for post-fledging female black ducks 

equipped with transmitters in Maine was 0.593; survival was 

0.694 when losses from hunting were censored (Longcore and 

others, 1991). This period estimate multiplied by interval rates 

for hunting, winter, and breeding periods produced an annual 

survival estimate of 0.262, about 12 percent less than the estimate (0.38) made on the basis of analyses of banding data.

Carney (1992) developed keys to identify species of 

wings submitted during harvest surveys, which facilitated 

estimating harvest of black ducks by hunters. Conroy and 

Krementz (1990) reviewed existing evidence that hunting was 

affecting the black duck population and discussed the biological basis of compensatory as opposed to additive mortality. 

Blandin (1992) determined population characteristics of black 

ducks through simulation modeling. Nichols (1991) presented an in-depth review of science, population ecology, and 

management of black ducks and reported that the statistical 

methods used in earlier papers had been inappropriate, thereby 

invalidating their conclusions. Clugston and others (1994) 

documented the effect of hunter kills related to habitat use 

for immature female black ducks at Escoumins, Quebec, in 

1991. The sample of radiomarked ducks was divided into three 

groups on the basis of the percentage of times (that is, telemetry locations) recorded in the St. Lawrence Estuary (table 2).

Most hunting took place in the estuary, so most ducks 

that avoided the estuary survived. These findings support 

the concept of additivity of hunting losses on breeding and 

staging areas described by Anderson and Burnham (1976, 

p. 41), who concluded the “threshold” of additivity of hunting losses “may be easy to exceed on the breeding grounds,” 

whatever that point might be. Kitchens (1994) determined that 

opening of hunting seasons disrupted use of prime feeding 

habitats in Missisquoi Bay in Vermont and Quebec, but use 

resumed when hunting seasons closed. Francis and others 

(1998) estimated annual survival during three periods on the 

basis of changes in harvest regulations. Mean survival rate 

increased from the first (1950–66) to the second (1967–82) 

period following initial restrictions on harvest, a finding that is 

consistent with a model of additivity of hunting mortality. The 

increase in survival rates following a second round of harvest 

restrictions revealed some evidence for an increase in survival 

for immature males between the second (1967–82) and third 

(1983–93) periods. For adults, however, survival increased 

less than expected if hunting mortality was additive. These 

researchers concluded that evidence of additive mortality 

existed in at least some age-sex classes of black ducks in all 

periods, but that evidence was weaker in the post-1983 period, 

perhaps indicating that harvest was falling below the threshold 

for additivity.

Table 2. Mortality of radiomarked black ducks relative to the percentage of times 

(that is, telemetry locations) that radiomarked ducks were in the Saint Lawrence 

Estuary.

[Modified from Clugston and others, 1994]

Percentage of telemetry 

locations recorded in 

the estuary

Mortality

Total ducks

Natural Unknown 

cause

Shot / 

probably shot

Less than 5 2 1 0 / 0 10

35–65 0 1 1 / 0 13

Greater than 95 0 0 10 / 2 15
Migratory Bird Research, Monitoring, and Management

Patuxent’s American Black Duck Studies from Chesapeake Bay to Maine and Beyond 75

Sauer and Droege (1997) reported that black ducks were 

more likely to be declining on Breeding Bird Survey routes on 

which mallards were observed than on routes without mallards. Krementz and others (1990) responded to criticisms 

of Dufour and Ankney (1990) about analytical methods used 

to test for a positive relation between body mass and annual 

survival of black ducks and determined that the criticisms 

were unfounded. Merendino and others (1993) speculated that 

“competitive exclusion” of black ducks from fertile wetlands 

was the primary cause for the long-term decline of the black 

duck population in many parts of Ontario. Hoysak and Ankney 

(1996), however, observing captive ducks, reported that mallards generally were not dominant over black ducks. Later 

in Maine, McAuley and others (1998) observed aggressive 

interactions of black ducks and mallards in the field during 

breeding. They found that male black ducks that instigated an 

interaction with male mallards did not lose any interactions 

and displaced mallards 87.2 percent of the time, whereas no 

change occurred during 12.8 percent of the interactions. In 

contrast, male mallards that initiated an interaction displaced 

black ducks during 63.3 percent of the encounters, but were 

displaced by the black duck during 15.0 percent of the encounters; the remaining 21.7 percent of the encounters resulted 

in no change. As objective fieldwork replaced conjecture, it 

became evident that “Science is nothing but organized common sense. The great tragedy of science [is] the slaying of a 

beautiful hypothesis by an ugly fact....” (Huxley, 1870, p. 6).

2000s

Although Patuxent scientists continued work on various 

studies during this decade, little attention was focused on contaminants. Field work in Maine (Longcore and others, 2006), 

however, revealed that low- (< 5.51) pH wetlands, although 

associated with reduced numbers of acid-intolerant macroinvertebrates, had large numbers of Insecta and supported a 

greater percentage of broods (78.6 percent), including black 

duck broods, than wetlands with a pH > 5.51, which supported 

21.4 percent of the broods. Longcore and others (2000b) compiled pertinent historical and more recent literature to prepare 

the Birds of North America series account for the American 

black duck. Haramis and others (2002, p. 22) evaluated 

productivity on Smith Island, MD, with radiomarked female 

black ducks and found that storm tides and predators kept nest 

success and productivity low.

Earlier, Francis and others (1998) reported that the 

threshold of additivity for black ducks, especially immature 

ducks, was exceeded in some years, which supported the 

caution of Anderson and Burnham (1976) that the “threshold” may be easily exceeded for adult females and young on 

breeding and staging areas. Therefore, the location and timing 

of mortality seem to determine whether hunting losses are 

additive. The time was early in the hunting season, and the 

location was on the breeding grounds and staging areas. It 

seems clear, then, how the geographic position of the northern 

United States and the Canadian provinces with respect to hunting regulations is crucial to the fate of the black duck population. Telemetry data from Nova Scotia, Quebec, and Vermont 

(Longcore and others, 2000a) further validated the contention 

of Anderson and Burnham (1976) that harvest on the breeding 

and staging areas could be severe, as 85 percent of all mortality in those northern study areas was associated with hunting. 

These data indicate that black ducks that are not shot on breeding and staging areas may have a high survival rate. Survival 

of immature female black ducks was determined on two 

adjacent study areas—one in New Brunswick (Parker, 1991), 

with an early October 1 hunting season opening, and one in 

Maine (Longcore and others, 1991), with opening delayed 

until November 15. Kaplan-Meier (Kaplan and Meier, 1958) 

survival rates for New Brunswick (0.945) and Maine (0.986) 

were similar in the 1- to 2-month period before hunting began, 

but declined sharply for marked ducks in New Brunswick 

when the hunting season opened (table 3). 

Most ducks in Maine that were not exposed to hunters in 

this period did not die. The decrease in survival rate in New 

Brunswick from 0.945 to 0.348 can be attributed mostly to 

hunter harvest. The next question, then, was whether black 

ducks respond if harvest is restricted.

The third Black Duck Symposium was held in 2002 

(Perry, 2002). Serie (2002, p. 2) discussed the black duck as 

a “species of international concern” and noted that the more 

restrictive harvest regulations beginning in 1984 may have 

stabilized the MWI for the black duck in the Atlantic Flyway. 

Another example of a response to harvest restrictions was the 

stabilization of the results of the breeding black duck survey 

in Quebec. Even after a sharp decline in numbers (from 27.5 

to 16.8 per 100 square kilometers [km2

] [71.2 to 43.5 per 

100 square miles (mi2)]) from 1990 to 1993, where the band 

recovery rate remained high, the count stabilized from 1994 

to 1995 (15.9 to 16.5 per 100 km2 [41.2 to 42.7 per 100 mi2] 

(Dickson, 1995) after retrieved kill declined substantially 

in Canada.

Table 3. Survival rate of radiomarked hatching-year female 

black ducks in Maine and New Brunswick, Canada, as a 

function of waterfowl hunting season opening date. 

[Modified from Longcore and others (1991) for Maine and Parker (1991) 

for New Brunswick, Canada; waterfowl hunting season in New Brunswick, 

Canada, opened October 1; waterfowl hunting season in Maine opened 

November 15]

Time interval 

studied

Location (years studied)

Survival rate in 

Maine 

(1985–87)

Survival rate in 

New Brunswick, 

Canada 

(1987–88)

Before September 30 0.986 0.945

October 1–15 0.965 0.500

October 16–31 0.885 0.465

November 1–15 0.834 0.348
76 The History of Patuxent: America’s Wildlife Research Story

In Maine, the Department of Inland Fisheries and Wildlife (P.O. Corr, Maine Department of Inland Fisheries and 

Wildlife, oral commun., 1983) monitored numbers of waterfowl broods, including black ducks, on 34 wetland broodrearing reference areas. During 1980–83, most duck seasons 

were 50 days long, with split seasons in the southern hunting 

zone that opened October 1st in the early or late season. The 

black duck daily bag limit was either one or two in 3 of 4 

years. In following years (1984–88), the season opening was 

usually delayed in the early split season to about October 15th 

in the north zone and about November 16th in the south zone. 

The daily bag limit was either zero or one in all split seasons 

except 1988, when it reverted to two black ducks per day with 

no delayed openings in any split season. Numbers of black 

duck broods on these 34 reference areas by year are shown in 

figure 1.

Delaying opening date, reducing season length, and 

reducing daily bag in this northern state positively affected 

the number of broods counted in years following protection of 

local breeding pairs. Reed and Boyd (1974) documented the 

high mortality of local black ducks breeding in the St. Lawrence Estuary during the opening weekend of hunting. Jorde 

and Stotts (2002, p. 31) dissected the Federal and State MWI 

data into geographic areas and showed that trends in the number of black ducks varied with geographic region.

Conroy and others (2002) assembled data on an array 

of variables affecting the black duck population and, with 

synthetic modeling, evaluated the relative importance of those 

variables. Longcore (2002, p. 7) contrasted the effects of 

variables in the summer and winter ranges of black ducks and 

1980 1981 1982 1983 1984 1985 1986 1987 1988

0

10

20

30

40

50

60

70

Year

Number of American black duck broods

Before harvest restrictions After harvest restrictions

Figure 1. Number of black duck broods on 34 index wetlands in 

Maine before (1980–83) and after (1984–88) harvest restrictions 

were applied to protect local breeding pairs. (Data from Maine 

Department of Inland Fisheries and Wildlife, Bangor, ME)

concluded that the proximate cause of the long-term decline 

of the black duck population was unlikely to be related to 

mallard distribution. Link and others (2006) examined black 

duck Christmas Bird Count (CBC) data on a regional basis 

and found decreasing populations in the southern and central 

parts of the wintering range, but more stable populations in 

the northeastern parts of the range. In addition, the CBC and 

the MWI showed similar patterns of population change at 

the scale of the United States, which lends credibility to the 

long-term MWI data. Zimpfer and Conroy (2006), in their 

attempt to model production rates in black duck populations, 

discovered that they could not include habitat variables as 

predictors and that multicollinearity among some predictors 

affected results, which indicated that the predictive ability of 

the models was limited.

Kirby and others (2000) published keys of wings to identify mallard, black duck, and hybrids of these species. Petrie 

and others (2000) found no differences in clutch size, nest success, hen success, duckling survival, or hen survival between 

black ducks and mallards in New Brunswick, but purported 

that the difference in population status of the two species was 

related to differences in breeding propensity arising from 

competition for breeding resources. In contrast, McAuley and 

others (2004) documented in nearby Maine that competitive 

exclusion of black duck pairs from fertile wetlands by mallards was unsupported by field observations, wherein 53 of 65 

(81.5 percent) wetlands visited for 2 hours or more were used 

by both black ducks and mallards. Increasing knowledge of 

black duck ecology and the positive effects of reduced harvest 

on the black duck population indicated that “In all science, 

error precedes the truth, and it is better it should go first than 

last” (Walpole, 1876, p. 128).

The emerging facts seemed to indicate that hybridization was not a likely cause of the black duck decline (Morton, 

1998; Bolen and others, 2002). Furthermore, competitive 

exclusion was not plausible in light of increasing beavercreated habitat (Longcore and Ringelman, 1980; Seymour and 

Mitchell, 2006), fewer breeding pairs (Longcore and others, 

1987), dynamic use of wetlands by both species (McAuley 

and others, 2004), the fact that the black duck is as aggressive 

as the mallard in defending territory and females, and the fact 

that the black duck is not dominated by the mallard (McAuley and others, 1998). Past studies also determined that black 

duck brood females are not excluded from fertile wetlands and 

black duck brood sizes are not different from those of mallards 

on fertile or infertile wetlands (Longcore and others, 1998), 

and that mortality of black ducks caused by hunters can be 

additive to natural mortality (Francis and others, 1998).

So, if not the mallard, what was causing the black duck 

population to decline? Bolen and others (2002) make a case 

that sensitivity (that is, wariness or neophobia) of black 

ducks toward humans may have contributed to the black duck 

population decline. Without question, the prime Chesapeake 

Bay wintering area for black ducks has been encroached on 

by humans around the bay, with a 38-percent increase (from 

2.0 to about 2.8 million) in the human population since 1970 
Migratory Bird Research, Monitoring, and Management

Patuxent’s American Black Duck Studies from Chesapeake Bay to Maine and Beyond 77

(Longcore, 2002). From the 1800s to the 1930s and 1940s, a 

consensus existed that excessive harvest was the cause of the 

decline in the black duck population. Even in the late 1960s, 

biologists and administrators agreed that harvest had to be 

reduced to stop the decline in black duck numbers (Barske, 

1968). The key question was, “What evidence exists to support a conclusion that the black duck population either has, or 

has not, been affected by harvest regulations?”

Population ecologists typically viewed hunting losses 

as compensatory—that is, no duck shot in fall or late winter 

will affect the spring breeding population. In other words, 

we believed that hunter kill never exceeded a threshold of 

additivity, whatever that threshold might have been. Francis 

and others (1998), however, reported that hunter harvest could 

exceed the threshold and be additive to natural mortality. 

Because restrictions on the breeding grounds (mostly in 

Canada) were not effective until about 1990, the reductions in 

the United States harvest could only stabilize the MWI in the 

Atlantic Flyway (Serie, 2002, p. 3). Because few black ducks 

now breed in the United States (as opposed to Canada), a substantial response in population growth probably cannot be 

expected until the number of breeders that return to the major 

breeding grounds increases.

Restrictions on harvest in the United States and Canada 

since 1992 have reversed the downward population trend 

(Longcore and others, 2000b). Breeding ground pair surveys initiated in the 1990s indicated that as harvest has been 

reduced (fig. 2), the number of black ducks has increased substantially (fig. 3) while the mallard population also increased 

substantially (fig. 4).

y = 19,840.8 – 9.3x

Adjusted r 2

 = 0.77; p = <0.0001

1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010

150

200

250

300

350

400

450

Year

Number of black ducks (X 1,000)

harvested in North America 

Figure 2. Number of black ducks harvested in North America, 

1990–2008. (Data from Office of Migratory Bird Management, U.S. 

Fish and Wildlife Service, Laurel, MD; <, less than)

1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010

350

400

450

500

550

600

Year

Number of breeding black ducks (X 1,000)

in North America

y = -11,077.2 + 5.78x

Adjusted r 2

 = 0.45; p = 0.0009

Figure 3. Number of breeding black ducks in North America, 

1990–2008. (Data from Office of Migratory Bird Management, U.S. 

Fish and Wildlife Service, Laurel, MD)

1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010

320

400

380

360

340

420

440

460

480

Year

Number of breeding mallards (X 1,000)

in Eastern survey

y = 19,949 + 5.18x

Adjusted r 2

 = 0.63; p = <0.0001

Figure 4. Number of breeding mallards in Eastern Survey, 

1990–2008. (Data from Office of Migratory Bird Management, U.S. 

Fish and Wildlife Service, Laurel, MD; <, less than)
78 The History of Patuxent: America’s Wildlife Research Story

Future Challenges

The original goal of the Black Duck Management 

Plan for North America, 1980–2000 (Spencer, 1980), was 

to “...reverse the apparent downward population trend...” 

as expressed in the MWI. As indicated by data from the 

improved waterfowl breeding pair survey, that goal has been 

achieved; however, this success resulted largely from reducing harvest by applying restrictions in areas where opportunity 

for exceeding the threshold of additivity was small—that is, 

south of the primary breeding and staging areas. Conjecture 

about the role of the mallard in the black duck decline was not 

supported by objective field studies of sympatric populations 

of these species. Additive effects of hunting were exposed as 

the black duck population began to recover following substantial reductions in harvest. Even after 80 years of research, 

an expanding human population, which will increase human 

disturbance and neophobia (Bolen and others, 2002), and 

energy development across Canada may affect where black 

ducks can breed or winter, thereby affecting productivity. 

For example, some wintering populations of black ducks are 

shifting northward (Brook and others, 2007), which may affect 

breeding success or survival, but the outcome is unknown. 

Over the long term (1955–2007) in Maine, size of waterfowl 

broods, including those of black ducks, seems to be declining (Schummer and others, 2011); this decline may indicate 

contaminant effects on egg hatchability or increased duckling 

mortality. Changes in brood survey methods, however, may 

have affected these results. For the early brood counts, broods 

of one or two ducklings were considered “incomplete broods” 

and were not included in calculating average brood size (H.E. 

Spencer, Jr., Maine Department of Inland Fisheries and Wildlife, oral commun., 1983), thus biasing the means higher than 

they would have been if broods of all sizes had been included. 

The next generation of black duck biologists will undoubtedly 

be vexed by some of the old issues and faced with new challenges to sustain the North American black duck population.

Acknowledgments

I thank Lynda J. Garrett (Patuxent Wildlife Research 

Center [Patuxent]) for always finding the reference I needed, 

Brad Allen (Maine Department of Inland Fisheries and Wildlife) for supplying harvest regulations for Maine, and Matthew Perry and Shannon Beliew (Patuxent) for reviewing and 

editing this manuscript, which also benefited from reviews 

by Daniel McAuley (Patuxent) and Patrick Devers (U.S. Fish 

and Wildlife Service). My Orono field station colleagues Dan 

McAuley and David Clugston; University of Maine graduate students James Ringelman, Catherine Frazer, and Charles 

Kitchens; and many summer biological technicians contributed substantially to research on black ducks at the Maine 

field station. The many and varied publications by the Patuxent staff about black ducks attest to the center’s multifaceted 

approach to investigating all relevant variables to improve 

understanding of black duck ecology and population dynamics. The consistent and persistent advocacy of private citizens 

and waterfowl managers was essential to expose conjecture 

and obtain objective data to explain and propose actions to 

reverse the long-term population decline of the black duck.

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Environmental Contaminant Research Program

Lucille and Bill Stickel: A Personal Perspective

By Nancy C. Coon

The Early Years

In late 1966, my husband, Richard, and I moved to the 

Washington, D.C., area, where he had been assigned to the 

National Naval Medical Center as a Medical Service Corps 

officer. Thinking that there might be something for me to do 

on the Washington Mall, I went to the Civil Service Commission and talked to a nice lady named Anna Berozowski. Ms. 

Berozowski told me that she knew a woman at the Patuxent 

Wildlife Research Center (Patuxent) in Laurel, MD, who occasionally came down to look through applications. She said she 

would call to see whether Dr. Lucille Stickel might be interested in talking to me. A few days later, Dr. Stickel did indeed 

call me, and invited me for a visit. I remember well my tour 

of Patuxent in the Stickels’ Pontiac Tempest convertible. I was 

hired as a junior biologist working directly with Dr. Stickel. 

That was the beginning of a 40-year relationship with Dr. 

Lucille and her husband, Mr. William Stickel. Through the 

years, I came to know both of them very well. Their profound 

dedication to their work often made it difficult for others to 

understand them, particularly Dr. Stickel. She would forever 

be regarded by some as unapproachable, but by others as 

compassionate and friendly. She was a pioneer, and a person 

of immense achievement. When she began her research, it was 

rare for a woman even to participate in science, much less to 

triumph to such a degree.

In March 1998, Richard and I had a conversation with 

Lucille in which she shared with us some details about her 

early years. She said that her maternal grandfather was a 

successful lumberman and merchant in Michigan, having 

emigrated from Canada. He owned land near Alpena, including a lakeside property on which the family had cottages even 

at that time. Lucille was born in Hillman, MI, in 1915. It was 

there that her love for all natural things began as she roamed 

the fields, woods, and lakeside. Lucille’s father died during the 

influenza epidemic that followed World War I, and her mother 

had a difficult time. Then the Great Depression (hereinafter 

Depression) came, and the family lost everything.

Lucille was fortunate enough to attend Eastern Michigan 

University, but worked 30 hours per week while taking a full 

academic load. After she graduated from college, she taught 

for 1 year at Ypsilanti, MI. In her view, she did well teaching 

biology, but she did not enjoy teaching math. She decided that 

Lucille and Bill Stickel, Nanjemoy River, MD, 1952. Photo by Francis M. Uhler, 

Patuxent Research Refuge.

she was not destined to be a teacher and made the decision to 

return to school at the University of Michigan. She was told 

that women would have difficulty obtaining jobs and would 

not be hired before men unless they had top grades, so that 

was her goal, and she succeeded. Lucille received her master’s 

degree in biology in 1938, and then began working toward her 

Ph.D. A duplication issue arose when, in her literature review, 

she came across a paper that essentially reported on her 

research topic (the embryology of an insect). Consequently, 

Lucille, not one who was easily discouraged or deterred, 

began searching for a new research topic.

Bill Stickel was born in Terre Haute, IN, in 1912. He 

attended Indiana State University for 2 years before transferring to the University of Michigan, where he met Lucille. He 

graduated with Bachelor of Science (1934) and Master of 

Science (1935) degrees in zoology/botany. He then continued 

research at the University of Michigan until 1939.

Bill accepted a position as a wildlife biologist with the 

Civil Service Commission in Washington, D.C., in 1940. He 

transferred to Patuxent in 1941, and Lucille joined him there. 

It was at Patuxent that Lucille selected a new research topic, 

one centered at Patuxent. In 1941, Bill and Lucille were married and thus became lifelong research partners, and stalwart 

supporters of each other.
88 The History of Patuxent: America’s Wildlife Research Story

Bill and Lucille Stickel on vacation along Steinhatchee River, Taylor County, FL, December 26, 1950. Photo by Francis M. Uhler, 

Patuxent Research Refuge.

A Beginning at the Patuxent Wildlife 

Research Center 

During the early years at Patuxent, Lucille was offered 

several positions, including one as an editor, but declined each 

of them, stating that the men with families recovering from the 

Depression needed the paying jobs more than she did. In 1943, 

after spending time as a volunteer, Lucille accepted a position 

as a junior biologist, beginning a long and illustrious career 

that helped pave the way not only for women in science, but 

also for the field of environmental pollution research.

In the early 1940s, Lucille began studying the common 

box turtle (Terrapene carolina) at Patuxent. Perhaps it was 

only a “folklore story,” but some staff members were told that 

it was the Stickels’ walks in the Patuxent woods with their 

dogs and Lucille’s love for mushrooms that caused her to 

begin recording her observations and, subsequently, marking 

box turtles. After 1 or 2 years of data collection on box turtles, 

Lucille sent a partial manuscript to the University of Michigan asking them to consider box turtles as her new research 

topic. The University of Michigan approved her request, so 

she continued her box turtle research and received her Ph.D. in 

1949. Lucille’s research on box turtle populations at Patuxent 

spanned several decades, as did her work with her husband, 

Bill, on black rat snakes (Elaphe obsoleta obsoleta). The 

common box turtle work continues today, and is remarkable as 

a study of a wildlife species that has continued for decades. In 

recognition of her pioneering work, the Box Turtle Conservation Workshop Committee established the Lucille F. Stickel 

Box Turtle Research Award to contribute to the survival of 

wild box turtle populations.

Dr. Stickel’s interest in plants and animals extended far 

beyond her well-known research interest in contaminants. 

She published six papers in the Journal of Mammalogy about 

populations of small mammals, especially the estimation of 

home range size. Her scientific work distinguishes her as a 

member of a small but notable group of women who made 

important early contributions to the field of mammalogy.

During World War II, Bill was on military furlough from 

June 1943 to December 1945, serving in the U.S. Army’s 

38th Malaria Survey Unit in New Guinea and the Philippines. Not surprisingly, while there, Bill collected reptiles and 

amphibians, which he donated to the U.S. National Museum. 

His animal collections included several new species, including one new frog species named for him (Kaloula conjuncta 

stickeli). Lucille told Richard and me that when he returned to 

the United States, Bill spent some time in a military hospital 

near Asheville, NC. The hospital stay may have influenced 

the Stickels’ selection of a retirement home in western North 

Carolina. Bill returned to Patuxent in 1945 and resumed 

his research.
Environmental Contaminant Research Program

Lucille and Bill Stickel: A Personal Perspective 89

The Prime Years at Patuxent

Throughout their long careers, the Stickels dedicated 

their lives to the field of wildlife toxicology and played a 

major role in the development of the worldwide recognition 

of Patuxent as an eminent research institution. They were also 

deeply interested in its varied habitats, and were often seen on 

weekends picking up litter and pruning a few trees and shrubs.

From 1952 to 1959, Bill was the editor of “Wildlife 

Review,” which provided professional access to current 

research developments in the field of wildlife biology. Over 

the years, he answered many letters of inquiry to Patuxent, 

providing his unique insights in language that was readily 

understood. He also gave many tours of Patuxent to visiting 

dignitaries and the interested public.

Dr. Stickel published her first contaminant paper in 1946, 

reporting the results of a field study of a mouse population in 

an area treated with DDT. At that early date, virtually nothing 

was known about the harmful effects of pesticides on wildlife. Pioneering research by the Stickels and their colleagues 

formed much of the basis for Rachel Carson’s groundbreaking 

1962 book, “Silent Spring,” which alerted the world to the 

dangers of pesticides (Carson, 1962).

In the early 1960s, biologists did not know conclusively 

the cause of population declines in several species of birds 

that were feeding high on the food chain. Eventually, in 1969, 

scientists at Patuxent published a paper linking dichlorodiphenyldichloroethylene (DDE), a metabolite of dichlorodiphenyltrichloroethane (DDT), to eggshell thinning in birds, 

which, in turn, resulted in reduced population recruitment 

(Heath and others, 1969). The Stickels’ concern with the toxic 

effects of environmental contaminants, especially pesticides 

and heavy metals, continued throughout their lives. Their 

research on the use of diagnostic tissue residues of contaminants represents one of the major accomplishments in the 

history of wildlife toxicology. They demonstrated that the 

concentrations of pesticides in the brains of dead birds could 

be used to determine whether those chemicals were responsible for their deaths. With Dr. Stickel’s leadership, Patuxent 

scientists provided the laboratory proof that chemicals were 

directly related to population declines in many bird populations, including brown pelicans (Pelecanus occidentalis) (Blus 

and others, 1977) and bald eagles (Haliaeetus leucocephalus) 

(Wiemeyer and others, 1993).

In 1968, Dr. Stickel received a Federal Woman of the 

Year award. She also received the U.S. Department of the 

Interior Distinguished Service Award. She was the first and 

only woman to date (2016) who received the Wildlife Society’s Aldo Leopold Memorial Award in recognition of her 

‘‘distinguished service to wildlife conservation,’’ a distinction 

she received in 1974. Dr. Stickel also was the first woman to 

direct a major Federal fish and wildlife laboratory, serving 

as Patuxent’s director from 1973 until 1981. Throughout the 

years, she was recognized as the ‘‘first lady’’ of the U.S. Fish 

and Wildlife Service, a mantle she wore with humility, but also 

with grace and charm.

Retirement

The Stickels remained at Patuxent, living in modest 

government housing, until their retirement, with a combined 

total of 81 years of government service, in March 1982. They 

retired to the mountains near Franklin, NC, where they spent 

many happy years identifying the flora and fauna on their 

property and the surrounding area, caring for their varied collection of dogs, and supporting local land conservation efforts.

Lucille’s interest was in ferns and fungi, two that were 

difficult to study. Bill collected many plants, worked cooperatively with Western Carolina University in Cullowhee, 

NC, and added many species to plant distribution records for 

Macon County, NC, where they lived. Not surprisingly, the 

Stickels set up a laboratory in the lower level of their home to 

facilitate their work.

Lucille often inquired about the status of people they 

had worked with at Patuxent. Bill, on the other hand, did not 

participate in these discussions and stated that he wished to 

remember Patuxent and its staff as they were when he and 

Lucille left. They did not return to Patuxent during retirement.

Bill Stickel died on February 11, 1996, after a lingering illness. For many years, Bill and Lucille had hiked in the 

mountains on and near their property, drawing detailed maps 

and observing and recording interesting plants and animals. 

Lucille continued to hike even when Bill was no longer able to 

do so, leaving detailed maps of her travels with his caregivers. 

Eventually Lucille and her dog, Sharlie, moved to a villa in a 

retirement community in Asheville, NC.

Even after all the intervening years, Dr. Stickel’s profound influence on the field of contaminants research remains. 

The approximately 40 research scientists she hired at Patuxent have published more than 1,000 scientific papers, chaired 

Thanksgiving dinner at the Stickels’ home at the Patuxent Wildlife Research 

Center, Laurel, MD, 1951 (from left to right: Bill, Lucille, Clark Webster, Lois 

Horn, Fran Uhler, and Helen Webster). Photo by Francis M. Uhler, Patuxent 

Research Refuge.
90 The History of Patuxent: America’s Wildlife Research Story

many symposia, and authored many books in the biological 

sciences. Several of these scientists have gone on to leadership 

roles in the U.S. Fish and Wildlife Service, the U.S. Geological Survey, universities, and private industry. As a testament 

to her continued influence and the respect with which she was 

regarded, two groups of research scientists she selected, mentored, and inspired visited her at her home in Asheville in late 

2006. That 2006 visit was our last visit with her, and she died 

in Asheville on February 22, 2007 (Coon and Perry, 2007).

Mrs. Lilian Linduska shared some thoughts with me after 

hearing of Lucille’s death. She and her husband, Dr. Joseph 

Linduska, lived at Patuxent in the 1940s. Lilian’s memories 

are of “a warm and attractive and caring friend. She and Bill 

loved dogs and always had one or two. She was also a great 

hostess and party giver. Some of her recipes are still in my 

files marked with a star indicating they are especially good.” 

I am also fortunate to have some of Lucille Stickel’s recipes.

On November 15, 1998, more than 50 years after her first 

publication on contaminants appeared, the Society of Environmental Toxicology and Chemistry, at its annual meeting in 

Charlotte, NC, announced that it would present its prestigious 

Rachel Carson Award to Dr. Lucille F. Stickel. That award is 

further evidence of the continuing importance of her many 

contributions to the field of wildlife toxicology.

References Cited

Blus, L.J., Neely, B.S., Jr., Lamont, T.G., and Mulhern, B.M., 

1977, Residues of organochlorines and heavy metals in 

tissues and eggs of brown pelicans, 1969–73: Pesticides 

Monitoring Journal, v. 11, no. 1, p. 40–53. [Also available at 

http://www.biodiversitylibrary.org/page/26096344.]

Carson, R.L., 1962, Silent spring: Boston, MA, Houghton 

Mifflin, 368 p.

Coon, N.C., and Perry, M.C., 2007, Lucille. F. Stickel, 

1915–2007: Journal of Wildlife Management, v. 71, 

no. 8, p. 2827–2828. [Also available at http://dx.doi.

org/10.2193/2007-333.]

Heath, R.G., Spann, J.W., and Kreitzer, J.F., 1969, Marked 

DDE impairment of mallard reproduction in controlled 

studies: Nature, v. 224, no. 5214, p. 47–48. [Also available 

at http://dx.doi.org/10.1038/224047a0.] 

Wiemeyer, S.N., Bunck, C.M., and Stafford, C.J., 1993, Environmental contaminants in bald eagle eggs—1980–84—and 

further interpretations of relationships to productivity and 

shell thickness: Archives of Environmental Contamination 

and Toxicology, v. 24, no. 2, p. 213–227. [Also available at 

http://dx.doi.org/10.1007/BF01141351.]

Lucille and Bill Stickel at a picnic table during a farewell party at the Patuxent Wildlife Research Center, Laurel, MD, 1982. 

Photo by W. James Fleming, U.S. Fish and Wildlife Service.
Environmental Contaminant Research Program

Lead Poisoning Studies and Shooting Tests 

with Soft-Iron Shot

By Jerry R. Longcore and Ralph Andrews

Background

Lead poisoning in vertebrates was first reported in Germany in 1842 (von Fuchs, 1842). Waterfowl deaths caused 

by ingesting toxic lead pellets deposited in wetlands across 

the United States have been recorded since 1874 (Phillips and 

Lincoln, 1930). Early reports of lead poisoning in waterfowl 

were made by Bowles (1908), McAtee (1908), and Wetmore 

(1919), among others. One proposed remedy was the use of 

a form of “disintegrable” lead shot—that is, shot made from 

lead-magnesium alloys (Green and Dowdell, 1936; Dowdell 

and Green, 1937). Jordan and Bellrose (1950) tested Lubaloy 

(copper-coated lead) pellets, a lead-tin-phosphorus alloy, a 

lead-magnesium alloy, and a lead-calcium alloy for toxicity in 

Pekin ducks, but none of these showed promise under test conditions. Jordan and Bellrose (1950) also tested the components 

of commercial shot (lead, arsenic, and antimony) and determined that lead was the sole cause of lead poisoning. They 

tested the effects of the aquatic plant coontail (Ceratophyllum 

demersum) in the diet of lead-dosed ducks and reported a 

beneficial effect. Elder (1950) measured hunting pressure in 

waterfowl in Delta Marsh, Manitoba, Canada, with a portable 

x-ray machine, and noted high percentages (22–49 percent) 

of juvenile mallard (Anas platyrhynchos), Northern pintail 

(Anas acuta), and redhead (Aythya americana) ducks with 

ingested shot.

Bellrose (1959) comprehensively documented the extent 

of lead-shot pellets deposited by hunters in wetlands across the 

four flyways and then ingested by waterfowl and found in their 

gizzards. The Mississippi Flyway Council Planning Committee (1965, unpub. report) brought attention to the unintentional 

deaths of waterfowl throughout the flyway and advocated 

action. A year later, Baker (1966) reported on the industrial status of lead shot pellet substitutes that were far from 

being perfected, and was not optimistic about a substitute, 

because lead is so well suited for making shot. The continuing decline in duck numbers, however, prompted administrators of the Bureau of Sport Fisheries and Wildlife (part of the 

U.S. Department of the Interior [DOI]) to join with industry, 

represented by the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI), to renew efforts to find or develop 

a nontoxic shot to replace lead shot in waterfowl hunting. 

In November 1966, SAAMI obtained proposals from three 

private research firms and then awarded a $100,000, 2-year 

contract to the Illinois Institute of Technology-Research Institute (IIT-RI) to develop a suitable substitute shot. Research 

biologists at the Patuxent Wildlife Research Center (Patuxent) 

evaluated each candidate shot for toxicity to ducks. Through 

a cooperative agreement (U.S. Department of the Interior, 

1966), industry was tasked with testing the shot for ballistics.

Search for Nontoxic Substitute Shot

The challenge for IIT-RI was to find a nontoxic material 

that was at least as dense as iron (steel), soft enough to avoid 

scratching or blowing out the choke of shotgun barrels, and 

available at a reasonable cost (that is, less than two times the 

price of lead). IIT-RI used three approaches to address this 

challenge (Andrews and Longcore, 1969). First, researchers 

would seek to find a biochemical additive, an organic compound with the ability to hinder the formation of soluble lead 

salts in a duck’s gizzard that could be added to powdered lead. 

This compound would then be extruded in wire form and cold 

headed (that is, the wire would be altered through force with 

a series of tools and dies) into shot. A second approach was 

to develop iron-lead composites in a thermoplastic binder. 

Low-carbon iron powder would be mixed with lead powder 

(to increase density), then coated with thermoplastic and 

extruded in wire form. The third approach was to develop 

a soft-iron shot by heating the iron to high temperatures to 

anneal commercial low-carbon steel wire, a process that 

produces wire that has an extremely coarse grain size and a 

low carbon content. During the first year of the contract, IITRI screened and bench tested many organic compounds and 

determined that a metallic ion-sequestering compound, ethylenediaminetetraacetic acid (EDTA), and the amino acid creatinine were the most promising. Attempts to extrude powdered 

lead into wire after the addition of small amounts of these 

compounds failed because the resulting wire was too brittle 

for use in fabricating shot. Similarly, the iron-lead thermoplastic mixtures were unsatisfactory because the flow properties 

of available thermoplastics were inadequate. The possibility 

of developing a soft-iron shot improved after a commercial 
92 The History of Patuxent: America’s Wildlife Research Story

low-carbon steel wire that cost only about 10 cents per pound 

was located. It was believed by the industry that annealing this 

low-carbon wire in wet hydrogen at 1,600 degrees Fahrenheit 

would produce a material soft enough for use in fabricating a 

suitable shot.

Evaluation of Proposed Substitutes at 

Patuxent Wildlife Research Center

In the summer of 1964, Jerry Longcore was hired as a 

biological technician in Patuxent’s Section of Wetland Ecology to assist Frank McGilvrey in waterfowl studies. Longcore’s appointment ended in 1965, but he returned in 1966 at 

the request of Section Leader John Sincock to assist as a coinvestigator with Ralph Andrews on the lead poisoning project.

Initial testing of potential substitutes for lead shot at 

Patuxent began in 1965. Locke and others (1966) documented 

the formation of acid-fast intranuclear inclusion bodies in 

kidneys of ducks exposed to lead. These inclusion bodies 

were an accurate marker of lead intoxication in ducks. Irby 

and others (1967) reported that plastic-coated lead pellets 

were just as toxic as the lead standard (96 percent mortality); 

a lead-magnesium alloy was one-half as toxic (54–63 percent 

mortality); and iron, zinc-coated iron, and copper were slightly 

toxic (0–12 percent mortality). A second batch of candidate 

materials (tin-lead alloy, zinc, nickel, Teflon-coated steel, 

and tin), all in shot form, was used to dose male mallards in 

a 30-day test (Grandy and others, 1968). The tin-lead alloy 

caused 27 percent mortality of test mallards; the zinc caused 

20 percent mortality. No mortality was observed with nickel, 

Teflon-coated steel, or pure tin.

Dosing of mallard ducks with proposed substitute shot 

types followed a standard protocol (Longcore and others, 

1974a). Most tests were conducted during 1967–69 in late fall 

through early spring, when ducks in wetlands in the wild are 

most typically exposed to spent shot. Replicates (3–5) of a 

five-duck group were given eight number (no.) 6-size pellets 

of a proposed substitute shot; and at the same time, replicates 

were dosed with eight no. 6-size commercial shot as a toxicity 

standard. For each toxicity test, control mallards (6–16) were 

maintained. The test diet was whole corn; test duration was 

40 days to evaluate shot retention and duck survival. Lead shot 

coated with nickel to various thicknesses reduced short-term 

mortality by one-half, but only delayed mortality until the 

nickel eroded. Combining tin with nickel did not reduce mortality (80 percent) because tin-nickel coating eroded, exposing 

ducks to lead. Steel shot plated with lead to increase density 

caused 95 percent mortality, whereas a thinner layer caused 

60 percent mortality. Mortality of mallards dosed with two different shot types formed with lead powder and a mucilage type 

or a polyvinyl acetate water-soluble binder (73 percent) was 

not different from that of those dosed with the lead-shot test 

standard (that is, eight no. 6 lead shot) (87 percent). Mortality of mallards dosed with a 1.4-gram (0.05-ounce [oz]) piece 

of wire containing either 1 or 2 percent creatinine or EDTA 

ranged from 75 to 90 percent, and was not different from mortality associated with the lead standard (70 percent).

The toxicity test results indicated that if a shot contained 

lead, the grinding action of the gizzard and acidic gastric 

juices usually would ultimately expose the lead and result 

in mortality. In 1933, one of the leading manufacturers of 

shotgun shells obtained a patent that claimed the addition of 

only 0.3 to 1.0 percent of phosphor-tin would render lead shot 

harmless to waterfowl (Jackson, 1933). The patent claimed 

“...actual experiments with the alloy upon wild ducks have 

shown it to be harmless.” A quantity of this shot was obtained 

from the company and compared with standard lead shot. All 

15 ducks in both groups on a corn diet died, but those dosed 

with the reputedly nontoxic shot died, on average, 4 days 

sooner than those dosed with commercial lead shot (Longcore, 

Andrews, and others, 1974). Finley and Dieter (1978) tested 

shot formed by combining lead with iron powder, referred to 

as “sintered” shot, in various amounts. Mortality was greater 

in ducks dosed with commercial lead shot than in those dosed 

with the lead-iron shot with a comparable amount of lead. 

Ingestion of two no. 4 lead-iron shot (0.004 oz of lead) caused 

slight weight loss and 5 percent mortality, but 45 percent of 

Impaction of proventriculus caused by ingested lead shot in the mallard on the 

left. Photo by Fred B. Samson, Bureau of Sport Fisheries and Wildlife.
Environmental Contaminant Research Program

Lead Poisoning Studies and Shooting Tests with Soft-Iron Shot 93

ducks dosed with five lead-iron shot died. Other candidate 

materials were not considered further for reasons of cost, malleability, production limitations, or low density with expected 

poor ballistics performance. 

In addition to proposed substitute shot evaluation, effects 

of commercial lead shot were tested among adult and juvenile male and female mallards with no difference in mortality 

(90–100 percent) among sex and age groups. No differences 

in mortality (93–100 percent) were detected among male and 

female game-farm mallards, wild mallards, or male American 

black ducks (Anas rubripes). Rattner and others (1989) dosed 

game-farm mallards, pen-reared black ducks, and wild black 

ducks with one no. 4 lead shot and fed the ducks pelleted feed. 

After 14 days, these ducks were redosed with two or four additional no. 4 lead shot. On the basis of all measures of lead toxicity (that is, mortality, weight change, delta-aminolevulinic 

acid dehydratase activity, and protoporphyrin concentration), 

black ducks and mallards were considered equally tolerant of 

lead. Longcore and Andrews (1974) noted, however, that commercial duck pellet feed seems to ameliorate the toxic effects 

of lead. In contrast, a single no. 4 commercial shot killed 18 

to 20 percent of either male or female yearling mallards on a 

corn diet during a 40-day test (Longcore and others, 1974a). 

Because Godin (1967) and others reported possible beneficial 

effects of oyster-shell grit in lead-poisoned ducks, we retested 

specifically to determine shot retention by fluoroscopy. We 

raised 50 grit-free mallards by transferring ducklings from 

brooders to wire-floored pens at 3 weeks of age and never 

exposed them to grit. Mortality of yearling, lead-dosed (five 

shot, no. 6 size) mallards offered oyster shell, quartz grit, or 

no grit was reduced in mallards fed oyster shell (only 4 of 12 

died) compared with those on quartz grit (9 of 12 died) or no 

grit (12 of 12 died). Survival was related to the number of shot 

retained more than 14 days and to the associated degree of 

erosion of the shot pellets (Longcore and others, 1974a).

Because foods eaten by ducks may mitigate the effects of 

ingested lead pellets, Andrews, Longcore, and others initiated a study in January 1967 to clarify earlier work (Jordan, 

1952). Jordan and Bellrose (1950) reported that of 80 mallards 

dosed with five no. 4 or no. 10 lead shot, only 5 ducks died 

(6.2 percent). We dosed 150 male mallards with either three or 

eight no. 6 lead shot and held birds on one of five diets—commercial duck pellets, whole corn, cracked corn, mixed small 

grains, or no food—for 40 days (Ralph Andrews and others, 

U.S. Fish and Wildlife Service, written commun., 1967). 

Seventy-five undosed male mallards also were held on the 

various diets to clarify the effect of diet on shot retention, shot 

erosion, production of acid-fast intranuclear inclusion bodies 

in kidneys (Locke and others, 1966), and mortality. We also 

monitored weight changes related to diet. On each of the grain 

diets, mortality was 80 percent for those groups of ducks on 

the eight lead-shot dose, whereas mortality was similar (20–

30 percent) for ducks on each of the grain diets and the three 

lead-shot dose. In contrast, only two ducks on the commercial 

duck pellet diet and dosed with eight lead shot died, and none 

of the ducks dosed with three lead shot died. We fluoroscoped 

surviving ducks on grain diets and determined that they lived 

because they voided shot before much of the lead could be 

eroded. Ducks fed commercial duck pellets, however, retained 

shot as readily as those on the grain diets, and the lead was 

rapidly eroded in their gizzard, but they did not show signs 

of poisoning. These data indicate that substances in the duck 

pellets may combine chemically with lead ions in the digestive tract and protect the ducks from poisoning. A follow-up 

study documented the efficacy of duck pellets. In late February 1967, each of 50 male mallards was dosed with eight no. 6 

lead shot. Twenty were given a diet of whole corn, 10 were 

given corn meal, 10 were given duck pellets, and 10 were 

provided with mats of the aquatic vegetation (that is, waterstarwort [Callitriche sp.]) in their water tanks. After 1 week, 

10 of the ducks on whole corn were switched to a diet of 

duck pellets. Mortality rates recorded were 100 percent on the 

whole corn diet, 70 percent on the corn-meal diet, 0 percent on 

duck pellets, 40 percent on corn followed by duck pellets, and 

40 percent on the aquatic vegetation. The Callitriche did not 

provide sufficient nutrients; therefore, duck pellets were supplied after 1 week for this group. We concluded that softness 

of the duck pellets was not the beneficial property and that this 

aquatic plant did not alleviate poisoning, but that duck pellets 

lessened the effects of ingesting lead even after signs of lead 

poisoning were evident. Lead is readily stored in bone and can 

be detected in many tissues, blood, and organs of organisms 

exposed to lead. The concentration of lead residues in tissue 

seems clearly diagnostic of acute lead poisoning in the mallard 

duck and was determined to equal or exceed 3 parts per million (ppm) in the brain, 6 to 20 ppm in the kidney, 6 to 20 ppm 

in the liver, and 10 ppm in clotted blood from the heart (Longcore and others, 1974b).

Evaluation of the Killing Efficiency of 

Lead and Iron Shot

The lack of emergence of any proposed shot type except 

iron shot as an alternative after all of the testing led to the big 

question: Does iron shot have adequate ballistics to effectively 

kill ducks at reasonable distances? Earlier, Bellrose (1959) 

had tested an annealed iron shot produced by Olin Mathieson 

Corporation (Clayton, MO) and determined that it performed 

almost as well as lead shot at distances of as much as 50 yards 

(yd) (Andrews and Longcore, 1969). The Mississippi Flyway 

Council Planning Committee (1965, unpub. report) reported 

on a comparative field test in which no. 2 iron shot killed 

ducks as effectively as no. 4 lead shot at a range of 40 yd, and 

resulted in fewer crippled ducks. Several studies documented 

that when lead shot was used, many ducks were crippled 

and not brought to bag, and that crippled ducks may recover 

(Tiemeier, 1941; Trautman, 1943; Whitlock and Miller, 1947; 

McGinnes and Beck, 1953; Kirby and others, 1981) and may 

even be harvested later. Bellrose (1953) stated that unretrieved 

kill was approximately 24 percent of total mallard kill and 
94 The History of Patuxent: America’s Wildlife Research Story

Tom Whittendale, Jr., and Jerry Longcore, U.S. Fish and Wildlife Service, weighing a duck used in the lead-shot 

study, Patuxent Wildlife Research Center, Laurel, MD, 1967. Photo by Fred B. Samson, Bureau of Sport Fisheries 

and Wildlife.

that only a small percentage of the ducks knocked down, but 

unretrieved, would actually recover. Because many uncontrolled variables were associated with field tests of shot loads, 

SAAMI and Patuxent agreed to cooperatively develop a 

shooting rig that would allow the operators to choose variables 

independently. The following paragraph from Andrews and 

Longcore (1969) describes the shooting facility.

“A unique duck-transport device was engineered 

by the ammunition industry and constructed at the 

Patuxent Wildlife Research Center. This automated 

shooting device moved a tethered, wing-flapping 

duck across a point where the mounted, pre-aimed 

gun fired a ‘perfect’ shot....A close simulation of a 

free-flying duck, passing a shooting position, was 

achieved. The shotgun was mounted on a movable 

wooden ‘horse’ and triggered by a solenoid activated through a micro-switch. Other micro-switches 

braked the carriage on forward and return trips.” [A 

glitch emerged in the braking system as the carriage 

went over the end of the track. Longcore observed 

the repeatable malfunction and deduced that the 

clutch-brake unit required a keyway in the shaft. 

Industry engineers, although skeptical, agreed to 

send a new shaft with keyway and key and, once 

installed, it worked well.] “...A movable control 

box for the entire facility was positioned beside the 

gun mount. Sighting stakes were erected for each 

shooting distance so that the gun could be accurately 

aimed prior to each shot. Standard 30-inch targets 

were shot to locate center of patterns and determine 

positions of sighting stakes. The targets were also 

used to assure that ducks were centered in the pattern prior to each day of shooting.”

Supplies for the test were provided by SAAMI. We used 

a 12-gage pump shotgun with a full choke and 30-inch (in.) 

barrel. Because iron shot could potentially affect the choke, 

which could in turn affect test results, additional barrels were 

used after a preset number of rounds had been fired through 

a barrel. The shot types tested were 2.75-in., 1.25-ounce 

loads of commercial no. 4 lead shot, and no. 6 lead shot as 

standards for comparison. SAAMI supplied 1,000 pounds of 

no. 4 soft-iron shot and loaded rounds with slow-burning ball 

powder for maximum muzzle velocity. The standard iron load 

was 1 ounce of shot that contained 180 pellets, which was 

identical to the 180 pellets in a no. 4 lead load. The load of 

iron shot was encased in a polyethylene liner to further protect 

gun barrels.

Three thousand game-farm mallards were maintained in 

fenced impoundments at Patuxent in 1967. Keeping them fed 

daily was taxing. We received help in maintaining the ducks in 
Environmental Contaminant Research Program

Lead Poisoning Studies and Shooting Tests with Soft-Iron Shot 95

Jerry Longcore and Tom Whittendale, Jr., U.S. Fish and Wildlife Service, 

readying the target to test the shot pattern in the lead-shot study, Patuxent 

Wildlife Research Center, Laurel, MD, 1967. Photo by Fred B. Samson, Bureau 

of Sport Fisheries and Wildlife.

an unexpected way. Serendipitous circumstances led Lorenzo 

King, a Washington, D.C., taxi driver, to become a biological 

technician and to participate in the shooting test. One day in 

Washington, D.C., John Gottschalk, Director of the Bureau 

of Sport Fisheries and Wildlife, hailed a taxi and was picked 

up by King. Gottschalk noticed a copy of an outdoor sporting magazine in the back seat of the taxi and questioned King 

about his interest in the outdoors and wildlife. King indicated 

that he was very interested, and subsequently applied for and 

was offered a job in the Section of Wetland Ecology at Patuxent, where he became part of the shooting-test crew.

Robert G. Heath, Patuxent’s resident statistician, used a 

split-plot statistical design to analyze the resulting data. Shooting distance made up whole plots, and combinations of shot 

type and sex of ducks, arranged factorially, made up subplots. 

Shot loads were patterned on a 30-in.-diameter circle for each 

distance before shooting to ensure the gun was centered for 

a “perfect” shot. For any given combination of shot type and 

distance, groups of five ducks, either male or female, were 

shot in random sequence. Shot patterns were obtained after a 

shooting day to ensure the gun and carriage were performing 

as required. Initial tests started in March 1968 were at 30, 40, 

and 50 yd, but because all shot types were effective at 30 yd, 

we replaced the 30-yd range with a 60-yd range and finished 

the tests in June 1968. Later, during November–December, we 

tested the effectiveness of shot loads at 45, 55, and 65 yd. The 

basic testing was done by firing at the broadside of the passing duck, but 300 additional ducks were shot from a nearly 

head-on direction at 40 and 50 yd for all shot types. Because 

of a keen interest in degree of crippling among shot types, we 

had finite kill categories: “instant kill” (< [less than] 1 minute 

[min]), “death in 1–5 min,” “death within 5 min to 1 day,” 

and “death within 1–10 days.” After each day of shooting, 

all dead ducks were weighed and examined for broken bones 

before they were stored in a freezer. Live ducks were kept on 

food and water for 10 days. Throughout most of this work, 

Tom Whittendale, Jr., was a valuable colleague and provided 

excellent support as the biological technician on the project. 

Ducks that were still alive after 10 days were euthanized with 

carbon monoxide, weighed, and fluoroscoped for embedded 

shot; a sample of 630 ducks was defeathered to count entrance 

and exit wounds. This task, like most tasks associated with this 

study, was somber. Every day, the empathy for the test ducks 

was etched in the faces of the crew. Although these longevity 

categories could not translate to field conditions, they were 

an objective way to compare effectiveness of shot types and 

inform about potential crippling losses.

The statistical examination of the shooting-test data by 

analysis of variance did not reveal differences (P = 0.05) 

between no. 4 lead and no. 4 iron shot in numbers of ducks 

Tom Whittendale, Jr., and Jerry Longcore, U.S. Fish and Wildlife Service, 

placing a duck on the transport cart during the lead-shot study at the Patuxent 

Wildlife Research Center, Laurel, MD, 1967. Photo by Fred B. Samson, Bureau 

of Sport Fisheries and Wildlife.
96 The History of Patuxent: America’s Wildlife Research Story

Gun firing automatically when the transport cart carrying the duck hits the 

micro-switch during the lead-shot study at the Patuxent Wildlife Research 

Center, Laurel, MD, 1967. Photo by Fred B. Samson, Bureau of Sport Fisheries 

and Wildlife.

“probably bagged” or numbers of “crippled and lost” ducks. 

No difference in vulnerability was detected between males 

and females. Shooting distance was the only highly significant 

(P = 0.01) variable related to percentages of ducks “probably 

bagged.” The no. 6 lead load, however, was slightly more 

effective (P = 0.05) than either of the no. 4 loads (180 pellets), 

most likely because of the greater number of pellets (300) in 

the no. 6 lead load.

When Winchester-Western decided to conduct its own 

shooting test in November 1972–March 1973, Dr. Charles 

Loveless (Assistant Director of Research, U.S. Fish and 

Wildlife Service [USFWS]) sent Longcore to East Alton, IL, 

to be the official observer. A duck transport facility, similar to 

that used at Patuxent but 100 feet long and with more amenities (for example, Plexiglas windows in the shed for the rig 

operators), had been constructed at Nilo Farms, Brighton, 

IL. One morning a black limousine arrived at the facility 

where Ed Kozicky and John Madson (Winchester-Western 

employees) and Jerry Longcore were preparing to operate 

the rig. John Olin and Nathaniel Reed (Assistant Secretary of 

Fish and Wildlife and Parks) emerged from the vehicle and 

were introduced.

After some explanations, it was time to demonstrate 

how the facility worked. We caught and tethered a mallard 

on the carriage; Mr. Kozicky loaded the shotgun and, when 

all was ready, he hit the switch. As the carriage crossed the 

firing point, the presighted gun fired and the load of shot killed 

the duck instantly, revealing the lethality of a nontoxic steel 

shot that could replace toxic lead. Mr. Olin inquired if the 

shot was lead shot and Mr. Kozicky replied that it was not; 

it was steel. Secretary Reed looked at Longcore and nodded, 

acknowledging the performance of steel shot. Although this 

was an impressive demonstration of the lethality of iron shot, 

Winchester-Western interpreted shotshell efficiency to be the 

ratio of the number of birds bagged to the number crippled 

(Kozicky and Madson, 1973). All of the ducks (2,400) used 

in the Nilo Farms test were sent to the University of Wisconsin, Madison, where Cochrane (1976) performed a detailed 

examination of the carcasses and the shooting-test results. 

Also, he compared results of the Nilo Farms test with those 

of Andrews and Longcore (1969) and concluded that the Nilo 

Farms no. 4 lead shot performed more effectively than the 

Patuxent no. 4 lead shot or the no. 4 steel shot. This result 

was not unexpected because of the greater weight and number 

of pellets in the Nilo Farms no. 4 lead load (that is, 1.5 oz of 

shot, 2.75-in. Winchester-Western Super-X, XX magnum shell 

with 198 pellets) compared with the Patuxent no. 4 lead load 

(that is, 1.25 oz of shot with 180 pellets [10 percent fewer]), 

which was a less robust load (Kozicky and Madson, 1973). 

Furthermore, the Nilo Farms no. 4 steel load (that is, 1.13 oz 

of shot with 214 pellets) was also a superior load compared 

with the Patuxent no. 4 steel load (that is, 1.0 oz of shot 

with 180 pellets). In addition, the Nilo Farms no. 4 lead load 

contained “Grex” (granulated, high-density polyethylene) that 

filled the interstitial spaces between pellets, thereby helping to 

maintain pellet sphericity (Lowry, 1973), which improved pattern density (the number of pellets in a 30-in.-diameter circle) 

from 75 to 88 percent (a 14.8-percent increase) (Cochrane, 

1976). The Nilo Farms no. 4 steel load also contained Grex, 

which resulted in a pattern density of 83 percent, in contrast to 

a pattern density of 70 percent for the Patuxent no. 4 steel shot 

load (Kozicky and Madson, 1973). The Nilo Farms no. 4 lead 

and steel loads were expected to perform better than Patuxent shotshell loads because the Nilo Farms shells had more 

pellets per load and, therefore, a greater pattern density, and a 

duck’s fate is determined by the number of pellets that strike it 

(Cochrane, 1976). Criteria used to designate bagged, crippled, 

and surviving ducks were defined more specifically. Kozicky 

and Madson (1973) maintained that the only true measure of 

shotshell efficiency as it relates to field conditions is the ratio 

of “birds bagged to birds crippled.” Despite the greater weight 

and number of pellets in the no. 4 lead and steel loads used 

in the Nilo Farms test compared to those used in the Patuxent test, many results were the same—no difference between 

sex and age groups; in broken bones within the categories of 

bagged, crippled, and survivor; in capacity to break wing or 

leg bones; in healing rates of bones; and in mean number of 

entrance wounds. Numbers of entrance wounds and embedded 
Environmental Contaminant Research Program

Lead Poisoning Studies and Shooting Tests with Soft-Iron Shot 97

shot were inversely correlated with distance for all shot types. 

Crippling rates per 100 mallards for the Nilo Farms no. 4 lead 

and no. 4 steel loads were inconsistent on the basis of the data 

of Kozicky and Madson (1973) and depicted in Cochrane 

(1976, fig. 3). At 50 and 60 yd, the crippling rate of no. 4 steel 

slightly exceeded that of no. 4 lead, but at 70 and 80 yd, the 

crippling rate of no. 4 lead substantially exceeded that of no. 4 

steel. The anomaly is that at 40 yd, the Nilo Farms no. 4 steel 

had a crippling rate of approximately 20 percent, whereas the 

no. 4 lead had a rate of approximately 7 percent as estimated 

from Cochrane (1976, fig. 3). This anomaly is not fully 

explained, but Lowry (1973) attributed better performance of 

no. 4 steel shot in the Patuxent test compared to that of the 

commercial no. 4 steel shot in the Nilo Farms test to difference in average temperature during shooting—66.5 degrees 

Fahrenheit (°F) at Patuxent and 36.5 °F at Nilo Farms. At the 

shooting preserve of the Max McGraw Foundation, Nicklaus 

(1976) tested no. 4 lead, no. 6 lead, and no. 4 steel on flying 

mallards released from towers and found no difference in crippling rates between lead and steel. The number of body shot 

in these flighted ducks did not differ between ducks shot with 

lead and those shot with steel, and was not statistically different from numbers of embedded shot found in wild populations 

(Bellrose, 1953).

In an Olin Corporation news item, Madson and Kozicky 

(n.d.) released the results of the Nilo Farms shooting test of 

lead and steel shot and attempted to estimate crippling loss for 

steel shot. They calculated an estimate based on the average 

annual bag of ducks as 10.6 million during 1955–71 with lead 

shot; then, if crippling loss is 20 percent, about 2.1 million 

more ducks are lost as cripples caused by lead shot. Applying 

the Nilo Farms data to a bag of 10.6 million ducks per season, 

they estimated the use of iron shot would increase crippling 

losses by 3 million ducks annually. John P. Rogers (USFWS, 

Migratory Bird Management Office), however, prepared a 

dichotomous key of what happened when a duck was fired 

on and examined 5-min kills for both lead and iron shot used 

in the Nilo Farms test and in the Patuxent shooting test. His 

interpretation of the average percentage of ducks not retrieved 

for all ranges (weighted—that is, 75 percent of all shots 45 yd 

or fewer) was 2.25 for lead and 6.1 for steel. Therefore, the 

weighted average was a 16.6-percent increase in unretrieved 

ducks with steel, resulting in a change from 2.1 million unretrieved ducks to 2.45 million unretrieved ducks—an increase 

of 350,000 ducks, not 3 million.

With a desire to move forward in implementing a ban on 

the use of lead shot over wetlands, Robert I. Smith and Longcore were assigned the task of drafting the initial Environmental Impact Statement in 1974 regarding the proposed use of 

steel shot for hunting waterfowl in the United States (U.S. Fish 

and Wildlife Service, 1974). The basement of Snowden Hall at 

Patuxent was the refuge where Longcore spent about 2 months 

reading documents and drafting sections of the Environmental 

Impact Statement, which was about 0.5 in. thick. The final 

Supplemental Environment Impact Statement for Hunting 

Migratory Birds in the United States increased the thickness of 

the document to about 2.5 in. by 1986 (U.S. Fish and Wildlife 

Service, 1986).

The Patuxent shooting tests (Andrews and Longcore, 

1969) clearly established the premise that a nontoxic substitute 

(that is, soft iron, or steel as tagged by its detractors) for lead 

shot could be developed. The stream of events that followed 

to implement steel-shot regulations are documented in Friend 

and others (2009). In 1978, Senator Ted Stevens of Alaska 

amended the DOI appropriations bill so that the USFWS could 

not enforce use of nontoxic shot without State approval. In 

Maine, for example, Longcore was directed to collaborate 

with the Maine Department of Inland Fisheries and Wildlife to 

sample duck gizzards and sediments in Merrymeeting Bay to 

determine whether nontoxic shot was necessary (Longcore and 

others, 1982). Incidence of ingested lead shot (5.9–8.1 percent) in the gizzards of black ducks from the bay during 

1976–80 exceeded the action threshold (5 percent).

Although steel shot was clearly capable of killing ducks, 

hunters complained about the higher cost of shells and the 

presumed higher rate of crippling, and their impression was 

that steel shot was ineffective. It soon became evident that 

hunters were having difficulty adjusting to the steel shot 

loads with ballistic characteristics (a smaller, but denser shot 

pattern; shorter shot string; the need to adjust aiming point as 

distance increased) different from those of lead shot. Hunters would shoot at a duck, miss the duck, and blame it on 

the shot load. Poor performance by hunters, in reality, was 

the result of their inexperience with an unfamiliar product 

(Tom Roster, Cooperative Nontoxic Shot Education Program, 

Klamath Falls, OR, oral commun., 1996). Tom Roster, an 

independent ballistic consultant, author, and mathematician, 

was also an avid waterfowl hunter who took an interest in the 

controversy. He conducted many steel-shot shooting clinics, 

including “participatory” shooting events for hunters; these 

educational efforts furthered the acceptance by hunters of 

switching to steel shot or a future nontoxic shot. Necessity was 

the mother of invention; ammunition manufacturers needed to 

respond to meet the demand for improved nontoxic shot loads 

(Taylor, 2011). To evaluate newly developed substitute shot 

types for toxicity, however, the USFWS needed a protocol 

to thoroughly test candidate substitutes following standard 

procedures. This was a timely effort, as the Final Supplemental Environmental Impact Statement for Hunting Migratory 

Birds was being published in 1986 and steel shot was the 

only nontoxic shot approved for hunting migratory birds. 

Ammunition companies, however, were gearing up to seek 

alternatives to steel shot. In just a few days in 1985, Patuxent scientists Susan D. Haseltine and Barnett A. Rattner (U.S. 

Fish and Wildlife Service, written commun., 1985) drafted a 

set of testing protocols for determining toxicity of candidate 

shot types to waterfowl, which was recast to the format of the 

Federal Register and published by Morehouse (1986). This 

early, amended set of protocols appeared annually for about 

10 years in the Code of Federal Regulations (Morehouse 

and Rattner, 1996). As use of other elements and compounds 

emerged in shot development, Dr. Rattner took the initiative 
98 The History of Patuxent: America’s Wildlife Research Story

not only to expand the guidelines for testing candidate shot (or 

coatings) on waterfowl, but to include tests covering effects on 

other aquatic fauna and flora. This ecosystem-oriented, tiered 

testing protocol was presented at the Fifteenth Annual Meeting 

of the Society of Environmental Toxicology and Chemistry 

(Rattner and Morehouse, 1994). After several lengthy delays, 

a final rule for the testing protocol was published (Perry and 

others, 1997). Rattner continued to advise the USFWS on testing guidelines and proposed nontoxic shot for approximately 

20 years.

Waterfowl ammunition has evolved with the use of 

higher velocity steel-shot loads, the development of hexagonal 

shot for more pellets per payload, and the substitution of loads 

composed of a blend of steel and tungsten shot, tungsteniron alloy, tungsten-polymer, tungsten-iron-nickel alloy, and 

bismuth alloy shot (Sanderson and others, 1997a, 1997b). 

Implementation of nontoxic shot has progressed from initial 

regulations on seven National Wildlife Refuges in 1972, to 

increased regulation in 1985, and to mandatory use of nontoxic shot for waterfowl hunting in the United States in 1991 

(Friend and others, 2009). Canada converted to nontoxic shot 

in 1999 (Taylor, 2011). Longcore recalls that, while expressing concern about how the public would react to the shooting 

of captive ducks, a high-ranking DOI administrator suggested 

that the steel shot should have been tested with bags of gelatin. 

This approach, however, would have been inadequate because 

of the need to objectively determine the lethality of steel shot 

and to evaluate its effects on crippling of waterfowl. The emotional effects on the crew of this difficult study were mitigated 

by the expected conversion to nontoxic shot that ultimately 

would prevent thousands of migratory waterfowl and scavenging raptors from being poisoned by lead, which causes many 

birds to starve before dying. Throughout the long process of 

seeking a nontoxic substitute for lead shot, many State wildlife 

agencies and nonprofit organizations, especially the National 

Wildlife Federation, supported Patuxent’s efforts and advocated for conversion to nontoxic shot for waterfowl hunting. 

The ultimate conversion resulted from a broad collaboration 

of Federal and State agencies, industry, and private citizens, 

whose persistent efforts greatly reduced the waterfowl leadpoisoning issue.

Acknowledgments

We thank Patuxent researchers B.A. Rattner and P.F.P. 

Henry for helpful reviews of the manuscript, and L.J. Garrett, 

Patuxent librarian, for obtaining difficult-to-find documents.

Tom Roster, contract ballistics specialist, U.S. Department of the Interior, instructing hunters on techniques for shooting with nontoxic shot, Montana, 

1994. Photo by Jeff Herbert, Montana Fish, Wildlife, and Parks Commission.
Environmental Contaminant Research Program

Lead Poisoning Studies and Shooting Tests with Soft-Iron Shot 99

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Environmental Contaminant Research Program

Patuxent Researchers Tackle Heavy Metal Poisoning 

in Wildlife

By Gary H. Heinz

An Early Memory

When I first arrived at the Patuxent Wildlife Research 

Center (Patuxent) in Laurel, MD, in 1969, I saw a device that 

resembled a small railroad track out in a field. When I asked 

what it was, I was told it was a trolley on which tethered 

game-farm mallard ducks (Anas platyrhynchos) were shuttled 

in front of a shotgun. Everything was automated: when the 

duck crossed a certain point, a perfectly aimed shotgun was 

fired. Jerry Longcore and his supervisor, Ralph Andrews, U.S. 

Fish and Wildlife Service (USFWS) biologists at the time, 

were comparing the killing efficiency of iron shotgun pellets 

and traditional lead pellets (Andrews and Longcore, 1969). 

They found that, at typical shooting distances, the iron shot 

were perfectly capable of killing a duck. At the time, such 

an experiment, in which more than 2,000 ducks were being 

sent in front of a shotgun to be killed—and some only badly 

wounded—did not raise any questions in my mind. Today, if 

such an experiment were to be proposed and submitted to our 

Animal Care and Use Committee, I strongly doubt it would be 

approved; however, back then, it was approved and the results 

of this scientific “duck killing experiment” were critical in 

saving millions of ducks and other waterfowl from dying each 

year from lead-shot poisoning.

Jerry Longcore was only one of many hard-working and 

dedicated research scientists who proved that lead was killing 

millions of waterfowl each year when the birds inadvertently 

swallowed the shot from the bottoms of marshes across 

the country. They not only showed that it was the swallowing of lead shotgun pellets that killed the birds, they also 

paved the way for the eventual banning of lead shot from 

waterfowl hunting.

Purpose and Scope

First, I am not attempting to review the entire history of 

Patuxent’s research on heavy metals. That could be a book 

in itself. I want to tell a short story that is not mired in all the 

heavy metals that were studied at Patuxent and all the publications that resulted from those studies. This story is as much 

about the people who studied heavy metals like lead as it is 

about the findings from their studies.

In this chapter, I share two often unappreciated observations: (1) it takes a surprisingly large group of dedicated 

researchers many years to bring about a change such as the 

banning of lead shot; and (2) even when one problem with a 

particular heavy metal, like lead shot, has been solved, different problems with the same heavy metal commonly surface 

down the road, and their solution can require an equally 

great effort.

Why Focus on Lead?

Why am I writing about lead contamination? First, I have 

personally been involved with some studies on lead, so I am 

familiar with lead toxicity. Second, studies on lead represent 

some of Patuxent’s most important contributions to solving 

contaminant problems, and success stories are what contaminant research is supposed to be all about.

For many years, I lived in a house on the Patuxent 

Research Refuge (Patuxent’s original name). One day my 

son, Brian, who was about 10 years old at the time, was out 

with two of his neighbor friends, Nate and Ben, exploring 

the marshes and ponds that dot Patuxent. They found a dead 

Canada goose (Branta canadensis) and brought it up to our 

house, asking me why I thought it had died. To give them 

a lesson in biology, I got a knife and I opened the goose. 

Everything looked normal. It had lots of fat. I did not see any 

injuries. I began to identify for them all the internal organs—

here is the heart, here is the liver, the lungs, and so forth. Here 

is the gizzard. So they asked, “What is the gizzard for? Why 

is it so big? Do all animals have one?” “Well,” I said, “I will 

open it up and tell you.”

As I slit through the muscular wall of the gizzard, the 

metal of the knife made a strange sound, like metal scraping 

against metal. Inside was the normal assortment of sand-sized 

to small-gravel-sized grit. To my surprise, however, mixed 

in with that grit was a total of 518 shotgun pellets, plus a 

half-dozen small lead fragments. Some of these pellets were 

rusted and, suspecting they were steel shot, I used a magnet 
102 The History of Patuxent: America’s Wildlife Research Story

and determined that 55 of the shot were, in fact, steel, but the 

remaining 463 were very small lead pellets—about size 9—

that might be used to shoot clay pigeons at a trap and skeet 

range. I guessed that this bird had been feeding at such a range 

and had picked up the shot, mistaking them for the grit it 

was seeking.

None of the shot had been eroded out of the normal, 

round shape into the flattened, disk-shaped pieces one typically finds in a bird that has survived long enough to have 

its gizzard grind away at the pellets. The several small lead 

fragments I found were probably pieces of lead shot that were 

created by collisions of the shot with other shot as they exited 

the shotgun barrel or as they collided with the clay pigeons 

they hit. The lack of erosion of the lead pellets, plus the fact 

that this goose had not progressed through the typical leadpoisoning phase of weight loss, suggested to me that the dose 

of lead shot likely was so massive that the bird had died of 

rapid, acute poisoning.

Holly Obrecht, our refuge biologist, told me he had found 

many dead geese that year, all with lead pellets in them. Holly 

sampled the mud on the bottoms of local marshes and visited 

local shooting ranges, trying to find the place where these 

geese had picked up their pellets, but he could never locate the 

source of all this lead shot. To my knowledge, all these years 

later, no one has ever found it.

Lead-Shot Research

Long before my son and his friends found the dead 

Canada goose, Patuxent researchers knew the same thing: 

ingesting lead pellets, even a few, can kill a bird. In 1951, Dr. 

Don Coburn and his coworkers published a paper in “The 

Journal of Wildlife Management” (Coburn and others, 1951) 

describing the toxicity of lead to mallards. A laboratory building at Patuxent was later named after Coburn and, for several 

decades, Coburn Laboratory was used for the study of the 

effects of lead and many other contaminants on birds.

In the 1960s, Lou Locke, the Patuxent veterinarian, and 

his coworkers George Bagley and H.D. Irby reported on the 

histopathological effects of ingested lead shot on mallards, 

leading the way in showing how to identify lead poisoning in 

dead birds (Locke and others, 1966; Locke and others, 1967). 

Lou was fun to be around and seemed to be at his happiest 

when he was examining a dead bird to determine what had 

killed it. In the late 1960s, interest rose in finding a metal 

that could be formed into shotgun pellets and was not toxic 

to waterfowl. Soft-iron pellets (later called “steel shot”) were 

determined to be satisfactory, as discussed above (Andrews 

and Longcore, 1969). In one Patuxent study, nine different 

types of shotgun pellets were compared for their toxicity to 

mallards (Irby and others, 1967). Simply coating lead pellets 

with plastic did nothing to reduce their toxicity, as the plastic 

was ground off in the gizzard; iron and copper shot, however, 

were nontoxic. Patuxent biologists also discovered that mourning doves (Zenaida macroura) could be exposed to lead shot, 

presumably mistaking them for grit (Locke and Bagley, 1967); 

therefore, other birds in addition to waterfowl were at risk.

In the 1970s, Patuxent scientists continued the research 

on lead-shot poisoning of birds. Wildlife biologist Mack 

Finley and physiologist Mike Dieter determined that merely 

mixing iron with the ballistically superior lead to make shotgun pellets did not completely resolve the poisoning problem 

(Finley and Dieter, 1978). Finley and Dieter joined with Lou 

Locke to show that lead-shot poisoning could be diagnosed 

by measuring an enzyme (delta-aminolevulinic acid dehydratase, or ALAD) in the blood of ducks (Finley and others, 

1976). At about the same time, Patuxent scientists were in the 

field, determining the number of waterfowl being exposed 

to lead shot (White and Stendell, 1977; Stendell and others, 

1979). Don White was a “no-nonsense” wildlife biologist who 

completed a study and promptly published it, then completed 

another study and published it; he was efficient and hard working. Rey Stendell went on to become a laboratory director at 

another U.S. Fish and Wildlife Service Research Center. An 

unusually large number of Patuxent scientists—I can think of 

nine off the top of my head—went on to become laboratory 

directors. I am not sure what that means; personally, I believe 

it indicates that Patuxent was a good training ground for future 

leaders, but perhaps there are other interpretations as well.

Biologists who were not in the contaminants program, 

but who did important work on lead shot, were frequently at 

Patuxent. For example, Joe Artmann and Woody Martin were 

never in the contaminants program and I do not think they 

did any other contaminant research, but they discovered that 

the sora rail (Porzana carolina) was another species that was 

ingesting lead shot in marshes (Artmann and Martin, 1975).

In the 1980s, Barnett Rattner and his colleagues determined that wild American black ducks (Anas rubripes) seemed 

to be more sensitive to lead poisoning than were game-farm 

mallards (Rattner and others, 1989). Barnett was a highly 

Joe Artmann (left) and Woody Martin, U.S. Fish and Wildlife Service, on rail 

study in Patuxent River marshes, Maryland, 1976. Photo by Matthew C. Perry, 

U.S. Fish and Wildlife Service.
Environmental Contaminant Research Program

Patuxent Researchers Tackle Heavy Metal Poisoning in Wildlife 103

Tundra swans killed by lead in sediments of Coeur d’Alene River, ID, 1991. 

Photo by Dan Audet, U.S. Fish and Wildlife Service.

trained physiologist who blended his academic skills with an 

expanding interest in wildlife biology—a transition similar to 

the paths that many wildlife biologists took toward a career in 

wildlife toxicology. Such blending of talents and interests was 

common in those days, when few professionals were actually 

academically trained in what is now called ecotoxicology. In 

his office, Barnett has a picture of a double-crested cormorant 

(Phalacrocorax auritus) he shot for contaminant analysis; 

not bad for a physiologist. In 2012, Barnett started his term 

as president of the Society of Environmental Toxicology and 

Chemistry, the largest professional society in the world dedicated to studying the effects of environmental contaminants on 

wildlife. This was a great honor for him and for Patuxent.

In one example of how Patuxent scientists with various academic backgrounds joined forces to study lead-shot 

poisoning, Chris Franson, a veterinarian at Patuxent, teamed 

up with Mike Haramis and Matt Perry, both wildlife field 

biologists, and John Moore, a chemist, to measure protoporphyrin (a precursor to hemoglobin in the blood) to reveal how 

many canvasbacks (Aythya valisineria) had been exposed to 

lead shot (Franson and others, 1986). Hank Pattee, who was an 

avid duck hunter and wholeheartedly embraced the transition 

to steel shot, demonstrated that predatory birds such as bald 

eagles (Haliaeetus leucocephalus) could be poisoned by eating 

lead-poisoned ducks (Pattee and Hennes, 1983).

The studies mentioned above are only a fraction of the 

work done at Patuxent to verify the threat of lead pellets to 

birds. It was not until 1991 that lead shot was banned for 

waterfowl hunting in the United States. From the first Patuxent study back in 1951 by Don Coburn, it had taken 40 years 

of dedicated research, not only by Patuxent scientists but also 

by a legion of other scientists, to gather enough convincing 

information to ban lead shot. However, the decades of work 

were well spent, as millions of waterfowl and other birds were 

spared death caused by ingestion of lead shot. As the development of nontoxic substitute shot expanded beyond the iron 

shot tested years earlier by Jerry Longcore, Barnett Rattner at 

Patuxent was designated as the scientist who would review the 

toxicity data generated for each of these proposed substitutes, 

making sure they would not pose a risk to birds.

So, With Lead Shot Banned, We Have 

Solved the Lead Problem, Right?

Unfortunately, no! Although lead shot was banned for 

waterfowl hunting in this country, there was no way to ban 

lead itself. The first problem with lead not associated with 

lead shot that came to the attention of Patuxent scientists was 

the emission of lead from leaded gasoline. Could lead from 

this source get into wildlife? To determine whether lead from 

vehicle emissions was getting into wildlife, Chris Grue, Dave 

Hoffman, and Nelson Beyer measured lead concentrations 

in the tissues of European starlings (Sturnus vulgaris) nesting near heavily used roads and in starlings nesting next to 

little-used roads at Patuxent. Lead concentrations were several 

times higher in starlings living near the heavily used roads, 

but reproductive success was not different (Grue and others, 

1986). With the phasing out of leaded gasoline between 1975 

and 1986, lead from gasoline ceased to be a source of lead 

in wildlife.

In the 1990s, Patuxent scientists began studying still 

another dangerous source of lead—mining operations. This 

work initially focused on lead contamination of the Coeur 

d’Alene River in Idaho. Each year, about 150 tundra swans 

(Cygnus columbianus) with lead poisoning would be found in 

the Coeur d’Alene River Basin. More than a century of mining 

operations left the sediments in much of the Coeur d’Alene 

River contaminated with lead. At first, lead was suspected to 

have moved up the food chain, as many contaminants do kill 

birds this way; however, studies with ospreys (Pandion haliaetus) by Chuck Henny and Larry Blus at Patuxent’s Corvallis, OR, field station demonstrated that lead was not moving 

up the food chain (Henny and others, 1991). Henny was a 

field biologist with a remarkable ability to detect previously 

unrecognized contaminant problems. Blus had already made 

his own mark decades earlier, demonstrating that dichlorodiphenyldichloroethylene (DDE), the metabolite of the pesticide 

dichlorodiphenyltrichloroethane (DDT), thinned the eggshells 

of brown pelicans (Pelecanus occidentalis).

Follow-up fieldwork by Henny and Blus strongly indicated that the tundra swans were getting their lethal dose of 

lead because they ingested some lead-contaminated sediment 

along with food they had gleaned off the bottom of marshes 

(Blus and others, 1991). To prove that the ingestion of leadcontaminated sediments was poisoning waterfowl at the Coeur 

d’Alene River, however, a series of controlled laboratory 

studies was needed. As is usually the case with contaminant 

problems affecting wildlife, a coordinated combination of 

field and laboratory studies is needed to fully understand the 

processes at work.
104 The History of Patuxent: America’s Wildlife Research Story

Back at Patuxent headquarters, a series of controlled 

feeding studies was conducted in which Coeur d’Alene River 

sediment was mixed into waterfowl diets at rates comparable 

to the sediment ingestion rates of wild birds. These studies 

proved that sediments collected from the Coeur d’Alene River 

contained enough lead to poison mallards, Canada geese, and 

mute swans (Cygnus olor); the mute swan served as a surrogate for the tundra swan (Heinz and others, 1999; Hoffman 

and others, 2000; Day and others, 2003).

The studies Patuxent scientists carried out on lead poisoning in Idaho were part of a Natural Resource Damage Assessment (NRDA) by the U.S. Department of the Interior (DOI). 

A NRDA is a legal process the DOI established to determine 

the degree of restoration needed to compensate the public for 

harm to natural resources because of the release of a hazardous substance into the environment. A court settlement was 

reached in the case of the mining companies that had released 

lead-contaminated sediments into the Coeur d’Alene River in 

Idaho. Approximately $370 million was awarded to clean up 

the Coeur d’Alene River Basin. This large court settlement 

validated the years of field and laboratory research carried out 

by Patuxent scientists and scientists from the USFWS. It is this 

kind of success story about contaminant research that gives 

scientists at Patuxent a great deal of pride, whether the success 

resulted from our contributions to the banning of lead shotgun 

pellets or led to the cleanup of a lead-contaminated river.

I mentioned at the outset of this chapter that it commonly takes a large and dedicated staff of researchers many 

years to bring about the resolution of a contaminant issue. 

This was clearly true of the various forms of lead contamination we studied over many decades at Patuxent. No one can 

be sure that some other source of lead contamination will not 

arise in the future that presents an equal research challenge. 

As I reflect on those “railroad tracks” I first saw in 1969—the 

tracks on which all those mallards were sent to be shot—I 

realize that Patuxent scientists of all kinds and with different training were up to the task of determining just what the 

contaminant issue was and how it might be solved. I feel 

privileged to have known them.

References Cited

Andrews, Ralph, and Longcore, J.R., 1969, The killing efficiency of soft iron shot: Transactions of the North American Wildlife and Natural Resources Conference, v. 34, 

p. 337–345.

Artmann, J.W., and Martin, E.M., 1975, Incidence of ingested 

lead shot in sora rails: Journal of Wildlife Management, 

v. 39, no. 3, p. 514–519. [Also available at http://www.jstor.

org/stable/3800393.]

Blus, L.J., Henny, C.J., Hoffman, D.J., and Grove, R.A., 1991, 

Lead toxicosis in tundra swans near a mining and smelting complex in northern Idaho: Archives of Environmental 

Contamination and Toxicology, v. 21, p. 549–555. [Also 

available at http://dx.doi.org/10.1007/BF01183877.]

Coburn, D.R., Metzler, D.W., and Treichler, Ray, 1951, A 

study of absorption and retention of lead in wild waterfowl 

in relation to clinical evidence of lead poisoning: Journal of 

Wildlife Management, v. 15, no. 2, p. 186–192. [Also available at http://www.jstor.org/stable/3796607.]

Day, D.D., Beyer, W.N., Hoffman, D.J., Morton, A., Sileo, 

Louis, Audet, D.J., and Ottinger, M.A., 2003, Toxicity of 

lead-contaminated sediment to mute swans: Archives of 

Environmental Contamination and Toxicology, v. 44, no. 4, 

p. 510–522. [Also available at http://link.springer.com/articl

e/10.1007%2Fs00244-002-1140-4.]

Finley, M.T., and Dieter, M.D., 1978, Toxicity of experimental lead-iron shot versus commercial lead shot in mallards: 

Journal of Wildlife Management, v. 42, no. 1, p. 32–39. 

[Also available at http://www.jstor.org/stable/3800686.]

Finley, M.T., Dieter, M.D., and Locke, L.N., 1976, 

δ-Aminolevulinic acid dehydratase—Inhibition in ducks 

dosed with lead shot: Environmental Research, v. 12, no. 2, 

p. 243–249. [Also available at http://www.sciencedirect.

com/science/article/pii/0013935176900323.]

Franson, J.C., Haramis, G.M., Perry, M.C., and Moore, 

J.F., 1986, Blood protoporphyrin for detecting lead exposure in canvasbacks, in Feierabend, J.S., and Russell, 

A.B., eds., Lead poisoning in wild waterfowl—A workshop: Washington, D.C., National Wildlife Federation, 

p. 32–37. [Also available at https://www.researchgate.

net/publication/277712385_Blood_protoporphyrin_for_

detecting_lead_exposure_in_canvasbacks.]

Grue, C.E., Hoffman, D.J., Beyer, W.N., and Franson, L.P., 

1986, Lead concentrations and reproductive success in 

European starlings Sturnus vulgaris nesting within highway roadside verges: Environmental Pollution, v. 42, no. 2, 

p. 157–182. [Also available at http://www.sciencedirect.

com/science/article/pii/014314718690005X.]

Heinz, G.H., Hoffman, D.J., Sileo, Louis, Audet, D.J., and 

LeCaptain, L.J., 1999, Toxicity of lead-contaminated 

sediments to mallards: Archives of Environmental Contamination and Toxicology, v. 36, no. 3, p. 323–333. [Also 

available at http://link.springer.com/article/10.1007%

2Fs002449900478.]

Henny, C.J., Blus, L.J., Hoffman, D.J., Grove, R.A., and 

Hatfield, J.S., 1991, Lead accumulation and osprey production near a mining site on the Coeur d’Alene River, Idaho: 

Archives of Environmental Contamination and Toxicology, v. 21, no. 3, p. 415–424. [Also available at http://link.

springer.com/article/10.1007%2FBF01060365.]
Environmental Contaminant Research Program

Patuxent Researchers Tackle Heavy Metal Poisoning in Wildlife 105

Hoffman, D.J., Heinz, G.H., Sileo, Louis, Audet, D.J., Campbell, J.K., LeCaptain, L.J., and Obrecht, H.H., III, 2000, 

Developmental toxicity of lead-contaminated sediment in 

Canada geese (Branta canadensis): Journal of Toxicology 

and Environmental Health, v. 59, p. 235–252. [Also available at http://dx.doi.org/10.1080/009841000156916.]

Irby, H.D., Locke, L.N., and Bagley, G.E., 1967, Relative 

toxicity of lead and selected substitute shot types to game 

farm mallards: Journal of Wildlife Management, v. 31, 

no. 2, p. 253–257. [Also available at http://www.jstor.org/

stable/3798314.]

Locke, L.N., and Bagley, G.E., 1967, Lead poisoning in a 

sample of Maryland mourning doves: Journal of Wildlife 

Management, v. 31, no. 3, p. 515–518. [Also available at 

http://www.jstor.org/stable/3798133.]

Locke, L.N., Bagley, G.E., and Irby, H.D., 1966, Acid-fast 

intranuclear inclusion bodies in the kidneys of mallards 

fed lead shot: Bulletin of the Wildlife Disease Association, 

v. 2, no. 4, p. 127–131. [Also available at http://www.

jwildlifedis.org/doi/abs/10.7589/0090-3558-2.4.127.]

Locke, L.N., Irby, H.D., and. Bagley, G.E., 1967, Histopathology of mallards dosed with lead and selected substitute 

shot: Bulletin of the Wildlife Disease Association, v. 3, 

no. 4, p. 143–147. [Also available at http://www.jwildlifedis.org/doi/abs/10.7589/0090-3558-3.4.143.]

Pattee, O.H., and Hennes, S.K., 1983, Bald eagles and waterfowl—The lead shot connection: Transactions of the North 

American Wildlife and Natural Resources Conference, 

v. 48, p. 230–237.

Rattner, B.A., Fleming, W.J., and Bunck, C.M., 1989, Comparative toxicity of lead shot in black ducks (Anas rubripes) 

and mallards (Anas platyrhynchos): Journal of Wildlife 

Diseases, v. 25, no. 2, p. 175–183. [Also available at http://

www.jwildlifedis.org/doi/abs/10.7589/0090-3558-25.2.175.]

Stendell, R.C., Smith, R.I., Burnham, K.P., and Christensen, 

R.E., 1979, Exposure of waterfowl to lead—A nationwide 

survey of residues in wing bones of seven species, 1972–73: 

U.S. Fish and Wildlife Service Special Scientific Report—

Wildlife, no. 223, 12 p. [Also available at https://archive.

org/details/specialscientifi223unit.]

White, D.H., and Stendell, R.C., 1977, Waterfowl exposure 

to lead and steel shot on selected hunting areas: Journal of 

Wildlife Management, v. 41, no. 3, p. 469–475. [Also available at http://www.jstor.org/stable/3800518.]
106 The History of Patuxent: America’s Wildlife Research Story

Gray squirrel in sycamore tree, Patuxent Research Refuge, Laurel, MD, 1973, Photo by 

Matthew C.Perry, U.S. Fish and Wildlife Service.
Environmental Contaminant Research Program

Role of Raptors in Contaminant Research at Patuxent

By Charles J. Henny

Introduction

This chapter reviews the history of and approaches used 

in studies focused on the effects of contaminants on raptors 

and raptor populations at the Patuxent Wildlife Research 

Center (Patuxent) in Laurel, MD. Worldwide raptor declines 

following World War II were unprecedented and resulted in 

a sequence of major efforts at Patuxent to understand their 

cause(s). The peregrine falcon (Falco peregrinus), bald eagle 

(Haliaeetus leucocephalus), and osprey (Pandion haliaetus) were the species of most concern in North America. 

Laboratory and field studies at Patuxent complemented each 

other and yielded timely results of national and international 

importance, including some findings published in the journals 

“Science” and “Nature.” 

Concern about contaminant effects on wildlife populations came to the forefront during the years immediately 

following World War II. This concern was worldwide and 

not limited to one taxonomic group or to personnel and 

investigations at Patuxent. Contaminant studies of raptors 

were only part of the story, but this review, with minor exceptions, is limited to raptor studies and the role Patuxent played 

in this research. Indeed, many important nonraptor contaminant studies done at Patuxent, as well as raptor studies conducted elsewhere, are not mentioned here. For other reviews 

of contaminant-wildlife issues in the 1950s and 1960s, the 

reader is referred to “Silent Spring” by Rachel Carson (1962), 

“Pesticides and the Living Landscape” by Robert Rudd 

(1964), and “Return of the Peregrine: A North American Saga 

of Tenacity and Teamwork” by Tom Cade and Bill Burnham 

(Cade and Burnham, 2003).

Early Years (Pre-1960)

Before 1960, few raptor studies were conducted at Patuxent or by personnel stationed there. The notable exception 

is the long-term red-shouldered hawk (Buteo lineatus) study 

Chuck Henny, U.S. Fish and Wildlife Service, with young red-shouldered hawk at Patuxent Wildlife Research Center, 

Laurel, MD, 1972. Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.
108 The History of Patuxent: America’s Wildlife Research Story

along the Patuxent River flood plain, initiated by Bob Stewart 

in 1943 (Stewart, 1949) and continued by Henny and others 

(1973) and Martin (2004). The study, which continues today 

(2016), was designed to improve understanding of habitat 

requirements, population densities, reproductive rates, and 

food habits, although a few eggs were analyzed for contaminants recently. Contaminant levels in eggs were generally low 

in the early 1970s, but habitat loss resulted in a long-term population decline of 78 percent from 1971 to 2002. Other studies 

prior to 1960 involved the development of techniques for livetrapping hawks and owls (Stewart and others, 1945) and the 

reporting of hawk migration count data (Robbins, 1950, 1956).

Raptor Pesticide Studies (1960–64)

The early 1960s brought the issues of raptor population 

declines and pesticides together. Earlier, James DeWitt (1956) 

at Patuxent had reported that pheasants and quail exposed 

to several pesticides in controlled laboratory conditions laid 

fewer eggs and produced fewer chicks than birds not exposed 

to pesticides, a finding that caused considerable concern 

among conservationists. Robbins (1960) evaluated the status 

of the bald eagle in summer 1959 by compiling information 

from the U.S. Fish and Wildlife Service (USFWS), State organizations, National Audubon Society, and private individuals. 

Charles Broley’s 20-year bald eagle dataset from the west 

coast of Florida was particularly alarming (Broley, 1958); it 

showed a 50- to 90-percent population decline, with markedly 

decreasing productivity rates after 1946. Broley (1958) and 

Robbins (1960) pointed out that Maurice Broun’s fall migration count data from Hawk Mountain Sanctuary in Pennsylvania showed that during 1935–40, 38 percent of the bald eagles 

migrating over the sanctuary were in immature plumage, but 

during the last 6 years of the study (1953–58), the percentage 

of immatures was only 21 percent. The percentage was especially low (10 percent) during 1957–58. 

DeWitt and Buckley (1962), in an interim report, noted 

that definitive proof of the cause(s) of the bald eagle population declines and lowered reproductive success was lacking, 

although it was postulated that prolonged and continued exposure to dichlorodiphenyltrichloroethane (DDT) and related 

pesticides might have been responsible. Bald eagles were 

trapped in Alaska in 1961 and 1962, brought into captivity at 

Patuxent, and fed various diets of DDT. These 1961–62 feeding experiments demonstrated that DDT could kill bald eagles. 

By 1963, Patuxent had obtained 54 dead bald eagles and 

5 unhatched eggs. All but one bird (from Alaska) contained 

detectable DDT residues (Buckley and DeWitt, 1963). Buckley and DeWitt (1963) concluded (1) wild eagles carry body 

burdens of DDT, but they were uncertain whether burdens in 

wild eagles were sufficiently high to be detrimental; and (2) 

all eggs analyzed contained DDT residues, indicating that 

some DDT was transferred to the egg, but they were uncertain 

whether DDT levels measured in the eggs affected hatching.

Peregrine Falcon Conference (1965)

The Peregrine Falcon Conference held in Madison, WI, 

in 1965 (Hickey, 1969) was a landmark event. Joe Hickey 

(University of Wisconsin) had organized a 1964 repeat of his 

1939–40 Peregrine Falcon Survey in the Eastern United States 

(east of the Mississippi River). Hickey’s (1942) data plus data 

from several additional sites yielded 209 perceived “valid” 

eyries, but Berger and others (1969), who checked 133 sites, 

found no occupied peregrine falcon eyries in 1964. The surveyors realized the impossibility of thoroughly covering the 

survey area, but emphasized that the species, if not extirpated 

in the United States east of the Mississippi River, was drastically reduced. Ratcliffe (1969) noted a sequence of peregrine 

falcon population declines in Great Britain that included egg 

breakage, egg-hatching failure, death of young, and failure 

of adults to lay eggs, which preceded actual desertion of 

the territory. Eggs from 14 peregrine falcons all contained 

residues of DDT/ dichlorodiphenyldichloroethylene (DDE, a 

metabolite of DDT), benzene hexachloride (BHC), dieldrin, 

and heptachlor epoxide, and Derek Ratcliffe, chief scientist, Nature Conservancy Council, United Kingdom, argued 

that concentrations in some were sufficient to account for 

sublethal effects leading to reduced breeding success. Similar population declines and low productivity were reported 

for ospreys in Connecticut (Peterson, 1969) and Michigan 

(Postupalsky, 1969).

John Buckley, former director of Patuxent, led a roundtable discussion on “pesticides as possible factors affecting raptor populations” with Joe Hickey, Ian Prestt, Lucille 

Stickel, and Bill Stickel. The primary focus was to review 

“what we know” and to identify “what we do not know” in 

1965. Lucille and Bill Stickel took an active role in the discussions (Hickey, 1969) and listed several tentative conclusions: 

(1) birds may have normal or near-normal reproductive success despite relatively high DDT residues in eggs (this was 

later recognized to occur with insensitive species); (2) there 

is no evidence that a few parts per million (ppm) of DDT in 

eggs causes reproductive trouble; (3) chlorinated hydrocarbon 

dosages that clearly reduce avian reproduction are, with possible exceptions, not far below those that will kill some birds 

if continued; (4) long-term intake of small doses is far more 

lethal than once thought; (5) declines in avian reproductive 

success with insecticidal dosages are almost always partial, 

are typically small, and are rarely eliminative; and (6) it is 

not characteristic of DDT, dieldrin, or most other chlorinated 

hydrocarbons to kill birds or to block reproduction without 

leaving residues that are substantial in relation to the toxicity 

of the chemicals involved—for example, DDT levels representing serious damage to birds will be well above 2 or 3 ppm 

of total residues. The Stickels noted that it was necessary 

to deal with these questions because there was still a strong 

tendency to attach much importance to low DDT residues, or 

pesticides in general, when we could have been missing the 

real causes of the population declines.
Environmental Contaminant Research Program

Role of Raptors in Contaminant Research at Patuxent 109

Early Patuxent field studies with DDT at application 

rates of 2 to 5 pounds per acre (Hotchkiss and Pough, 1946; 

Stewart and others, 1946; Robbins and Stewart, 1949; Robbins and others, 1951; Mitchell and others, 1953) resulted in 

mixed findings regarding effects on passerine bird populations. 

The Stickels at the round-table discussion further noted that 

although pesticides kill wildlife and may cause population 

declines, many other factors—for example, disease and metals, such as mercury and lead—do so as well. They concluded 

that more work was required in the study of behavioral effects 

and combinations of pesticides, and more wild species needed 

to be tested because sensitivity to contaminants differs greatly 

among species.

Regarding procedural matters, Lucille Stickel noted a 

serious bias when eggs were collected for residue analysis 

(especially failed eggs from nests) and suggested using the 

volume of the egg in its shell as an adjustment for moisture 

loss. This suggestion was first mentioned in 1965 (Stickel and 

others, 1965); a detailed paper (Stickel and others, 1973) was 

published 8 years later. Without the adjustment, residue concentrations on a wet-weight basis were inflated, commonly by 

50 percent or more. Some researchers today (2016) still make 

this mistake when reporting egg residues. Lucille believed the 

only way to verify lethal concentrations of contaminants in 

hawks was experimentally—that is, feed the birds a diet that 

contains the pesticide of concern while maintaining suitable 

controls. She also pointed out that birds that died during the 

lab experiments with DDT and DDE had brain concentrations of the same magnitude whether they died immediately or 

after months on clean food. Because concentrations in other 

tissues were highly variable, Patuxent recommended that, for 

diagnostic purposes, brain concentrations be used to establish 

the cause of death from chlorinated hydrocarbons (Stickel and 

others, 1969; Stickel and others, 1970). The Stickels downplayed the importance of egg breakage at this time (1965), and 

noted that it was not uncommon in captivity, even with birds 

not on dose.

Rapid Increase in Contaminant Studies 

(1966–90)

The pesticide-eagle studies at Patuxent by Buckley and 

DeWitt (1963) mentioned earlier were updated at the North 

American Wildlife and Natural Resources Conference by 

Stickel and others (1966), who concluded that (1) pesticide 

residue transfer from adult to egg is well known; (2) the 

quantity of residues that may indicate an adverse effect on 

hatching and survival is far from clear (but they noted that 

quantities of DDE, DDT, and dichlorodiphenyldichloroethane (DDD) in eagle eggs so far reported are much lower than 

those reported in gull and pheasant eggs that hatched or were 

alive, which provides little basis for suspecting that DDT in 

eggs prevented hatching); (3) exposure of eagles to DDT and 

dieldrin is nationwide; (4) at least an occasional eagle obtains 

enough dieldrin, and perhaps DDT, to place it at risk; and (5) 

most eagles that die in the United States today die of causes 

other than pesticide poisoning. Finally, the important question 

of sublethal effects on behavior, particularly parental behavior, 

could not yet be answered. Future research plans at Patuxent 

were also mentioned; they included (1) continue monitoring 

eagle eggs and adults for pesticide residues, (2) extend analyses to some of the more important heavy metals, (3) begin 

food-chain investigations specific to eagles, and (4) improve 

understanding of residues in eggs and tissues (Patuxent 

already had established a colony of American kestrels [Falco 

sparverius] to test for reproductive effects with a raptor).

Additional Patuxent field data on raptor populations were 

reported when Schmid (1966) compared the number of successful osprey nests and young banded per successful nest in 

parts of Cape May County, NJ, in 1937, 1938, and 1939 with 

numbers observed in 1963. This one-trip visit at banding time, 

of course, did not include those nests that failed, although the 

number of successful nests had decreased dramatically (perhaps by 60–70 percent) by 1963. Schmid concluded that possible explanations might be diminishing food supply, contaminants in the food chain, or a growing frequency of disturbance 

and persecution. Subsequent Patuxent field studies emphasized 

a much more detailed approach, which included methods for 

separating several of the possible factors that could cause 

population declines (for example, see the section below titled 

“Osprey” for a description of the osprey egg transfer study 

between Connecticut and Maryland).

At the time of the Peregrine Falcon Conference in 1965, 

eggshell thinning was not yet known; only the alarming and 

rapid declines of the peregrine and their unusual behaviors 

were recognized at many locations. No conclusions had yet 

been reached regarding the cause(s) of the declines at the 1965 

conference. Egg breakage was mentioned as one of the many 

factors that needed to be considered in evaluating worldwide 

peregrine population declines. Derek Ratcliffe left the conference with egg breakage on his mind and then talked with 

Desmond Nethersole-Thompson—a long-time friend of his, a 

field biologist, and an early egg collector—who suggested that 

Ratcliffe look at eggs in collections. Desmond’s suggestion 

was critical and led to the first understanding that eggshells 

themselves were affected along with, of course, the females 

that laid those eggs. Ratcliffe devised an eggshell “thickness 

index” because he could not directly measure eggshell thickness; the oologists who collected the eggs and removed the 

contents of the eggs prided themselves on making a very small 

hole in the eggshell. Ratcliffe reported his astounding results 

that eggshells were now thinner than in the past to Joe Hickey, 

professor at the University of Wisconsin, even before he went 

to press in “Nature.” Ratcliffe and Hickey were friends and 

talked on the phone often. Dan Anderson, a graduate student 

working with Hickey, was immediately sent to many museums 

in the United States to measure eggshell thickness with a modified micrometer that would fit through the tiny holes the egg 
110 The History of Patuxent: America’s Wildlife Research Story

collectors made (Daniel Anderson, University of California, 

Davis, oral commun., 2012). Hickey, whose long association 

with Patuxent dated back to his early studies of banding data 

from the Bird Banding Laboratory (Hickey, 1952), obtained 

USFWS funding for the eggshell-thickness project through 

Patuxent and Lucille Stickel.

Thus, Ratcliffe (1967), while investigating the peregrine 

falcon and sparrow hawk (Accipiter nisus) in the United Kingdom, noted a relation between decreases in eggshell weights, 

decreases in sizes of breeding populations, and exposure of 

populations of these species to persistent organic insecticides. 

Hickey and Anderson (1968) reported similar findings for 

North American species the next year. The observation was 

that eggshell thinning in archived samples of raptor eggs and 

Young eaglet in captive study at Patuxent Wildlife Research Center, Laurel, 

MD, 1970s. Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.

Brown pelican egg without eggshell, 1970s. Photo by Matthew C. Perry, U.S. 

Fish and Wildlife Service.

other species had occurred over a critical time, namely the 

period coincident with the post-World War II introductions of 

organochlorine (OC) pesticides and radioactive contamination; this was an important discovery. The next step involved 

a hypothesis that DDT (later discovered to be DDE) was the 

major cause of eggshell thinning and that this eggshell thinning was related to population declines through reduced reproductive success. The critical step was the testing for effects 

of DDT and dieldrin on eggshell thinning and reproduction 

of American kestrels at Patuxent under controlled laboratory 

conditions (Porter and Wiemeyer, 1969; Wiemeyer and Porter, 

1970). These controlled studies showed the same pattern 

of reproductive failure and reduced eggshell thickness that 

appeared in several raptor populations in the United States and 

Western Europe. This early laboratory work was completed 

under the direction of Lucille Stickel, whose leadership and 

insight, in addition to her command of the necessary resources 

for critical experiments, made it possible.

Eggshell thickness was an increasingly important factor and was studied intensively under controlled conditions 

at Patuxent. Thus, much of the work at Patuxent followed 

general concepts developed by the Stickels prior to 1965, with 

slight modifications—for example, eggshell thinning came to 

be considered much more important than had been anticipated 

in earlier years. One outcome of the discovery of eggshell 

thinning was the realization that in studying other contaminants it was beneficial also to study not only mortality, but also 

the subtle, insidious effects of the contaminants. Many of the 

people employed at Patuxent after 1965 were hired specifically to conduct various types of studies to complete missing 

parts of the contaminant story, not only for raptors, but also 

for all wildlife. Later studies extended to groups of contaminants other than OCs, including organophosphates (OPs), 

carbamates, anticoagulants, mercury, lead, selenium, fluoride, cadmium, flame retardants, chlorophenoxy herbicides, 

perfluorinated acids, and sulfates, as well as combinations 

of chemicals.

Laboratory Studies

The laboratory studies at Patuxent with American kestrels 

(table 1), eastern screech owls (Otus asio), and common barn 

owls (Tyto alba) (table 2) were many and involved many 

contaminants and endpoints. The compilation of reproductivesuccess and egg-residue data in a series of papers on a nest-bynest basis in the laboratory and field (see Blus [1984] for the 

sample egg approach) was used to estimate the proportion of 

a population adversely affected by various contaminants—for 

example, the percentage of eggs containing concentrations 

greater than a perceived critical level for reproductive effects 

(table 3). The critical residue concentration information was 

especially useful to the field biologist who was trying to interpret observed local contaminant concentrations.
Environmental Contaminant Research Program

Role of Raptors in Contaminant Research at Patuxent 111

Table 1. Patuxent Wildlife Research Center laboratory studies 

on contaminants in American kestrels, 1969–2011.

[DDT, dichlorodiphenyltrichloroethane; DDE, dichlorodiphenyldichloroethylene; PCB, polychlorinated biphenyl; anti-ChE, anti-cholinesterase; 

PBDE, polybrominated diphenyl ether; OP, organophosphate; OC, organochlorine]

Contaminant(s) Year(s) studied

Dieldrin + DDT 1969

Dieldrin + DDT, DDE 1970

DDE 1970

DDE 1972

Lead 1980

Parathion 1982

Oil 1982

Lead 1983

Lead 1984

Lead 1984

Methyl parathion, fenvalerate 1984

Lead 1985

Lead 1985

DDE, DDT + dieldrin 1986

Paraquat 1987

Lead + OCs 1989

Dicofol (kelthane) 1990

Diphenyl ether herbicides 1991

Aroclor 1248 1991

Four anti-ChEs 1991

PCB 126 1996

White phosphorus 1997

Aroclor 1248 1998

Planar PCBs 1998

OPs, carbamates 1998

Dicofol (kelthane) 2001

Aroclor 1242 2002

PBDEs 2005

Methylmercury 2007

Methylmercury 2009

PBDEs 2009

Methylmercury 2010, 2011

Diphacinone 2011

Table 2. Patuxent Wildlife Research Center laboratory studies 

on contaminants in eastern screech owl (Otus asio) and 

common barn owl (Tyto alba), 1972–98.

[DDE, dichlorodiphenyldichloroethylene; anti-ChE, anti-cholinesterase; 

OP, organophosphate]

Species Contaminant(s) Year studied

Eastern screech owl DDE 1972

Eastern screech owl Aroclor 1248 1980

Common barn owl Famphur 1980

Common barn owl Six anti-coagulants 1980

Eastern screech owl Endrin 1982

Common barn owl DDE, dieldrin 1983

Eastern screech owl Fluoride 1985

Eastern screech owl Fluoride 1988

Eastern screech owl Dicofol (kelthane) 1989

Eastern screech owl Four anti-ChEs 1991

Eastern screech owl Selenium 1996

Eastern screech owl OPs, carbamates 1998

Matt Perry banding young American kestrel at Patuxent Wildlife Research 

Center, Laurel, MD, 1975. Photo by U.S. Fish and Wildlife Service.
112 The History of Patuxent: America’s Wildlife Research Story

Table 3. Patuxent Wildlife Research Center studies1 to determine the 

effect of contaminant residue concentrations in eggs on productivity 

of various raptor species using the sample egg technique.

[DDT, dichlorodiphenyltrichloroethane; DDE, dichlorodiphenyldichloroethylene; 

PCB, polychlorinated biphenyl; OP, organophosphate; OC, organochlorine; Hg, 

mercury]

Species Contaminant(s) Author (Year)

American kestrel Heptachlor epoxide Henny and others (1983) 

Bald eagle OCs, PCBs, Hg Wiemeyer and others (1984) 

American kestrel DDE, DDT, dieldrin Wiemeyer and others (1986) 

Osprey OCs, PCBs, Hg Wiemeyer and others (1988) 

Bald eagle OCs, PCBs, Hg Wiemeyer and others (1993) 

1

The collection and analysis of an egg from a series of nests for these studies 

provided an approach to evaluate the percentage of individuals in a wild population whose reproduction was adversely affected by various contaminants.

John Maistrelli, U.S. 

Fish and Wildlife 

Service, transferring 

adult eagle at 

Patuxent Wildlife 

Research Center, 

Laurel, MD, 1976. 

Photo by Matthew C. 

Perry, U.S. Fish and 

Wildlife Service.

Field Studies and Monitoring

The status of several raptor species and various raptor 

populations was not well known in the late 1960s and 1970s. 

The concern focused strongly on the peregrine falcon, bald 

eagle, and osprey, all of which were prominently mentioned at 

the 1965 Peregrine Falcon Conference. In the mid-1960s, the 

peregrine falcon was already extirpated or nearly extirpated in 

the Eastern United States, and reintroduction was in progress. Given the devastating population declines in the Eastern 

United States, contaminant studies on peregrines at Patuxent 

focused on monitoring northern latitude breeding populations 

that migrated along the Atlantic Coast and the Texas coast 

by sampling blood to determine contaminant trends from 

1978–2004 (see Henny and others, 1982; Henny and others, 

2009). The nationwide bald eagle population had declined 

substantially and the species was very sensitive to disturbance 

at the nest; however, unhatched eggs and dead eagles were 

analyzed routinely at Patuxent. Therefore, the osprey became 

the obvious candidate for intensive field studies because it 

could be studied more easily in the wild.

Osprey

During the Peregrine Falcon Conference, exceptionally 

poor productivity or declining osprey numbers were reported 

for Long Island, NY; Connecticut; New Jersey; Rhode Island; 

Maine; Massachusetts; Wisconsin; and Michigan. Most 

localized studies that followed the conference included an 

evaluation of (1) reproductive success, (2) changes in population numbers over time (although few series with more than 

a decade of data were available), (3) contaminant residues 

in some eggs and fish, and (4) eggshell thickness. Because 

reproduction was the apparent “weak link” in the life cycle, 

the number of young fledged per nesting pair was considered 

of primary importance (table 4).

Structural modeling based on survival-rate estimates 

from banding data and life-history characteristics (funded 

by the Migratory Bird Populations Station [MBPS] at Patuxent) (Henny and Wight, 1969; Henny and others, 1970) was 

used to estimate a recruitment standard (0.95–1.30 young per 

nesting pair) needed to maintain a stable osprey population. 

At that time, most osprey populations were producing at what 

was considered extremely low rates, although the normal 

(or standard) rate was unknown. Observed production rates 

were compared to the standard rate, which was later lowered 

to 0.80 young per nesting pair on the basis of a comparison 

between the observed population response and the projected 

population response determined by using the model (Spitzer 

and others, 1983).

In 1968 and 1969, osprey eggs were exchanged between 

Connecticut (low reproduction) and Maryland (higher 

reproduction) nests to test the hypothesis that the decline in 

reproductive success of Connecticut ospreys was caused by 

something external to the eggs (Wiemeyer and others, 1975)—

for example, recall the concerns mentioned above about food 

supply, persecution, and human disturbance in the 1960s. 

A cartoon of the era representing the egg exchange study is 

shown in figure 1. Incubation of Connecticut osprey eggs by 

Maryland ospreys did not improve the hatching rate. Maryland 

eggs incubated by Connecticut ospreys hatched at their normal 

rate. The results of the exchanges and associated observations 

indicate that the most probable cause of the poor reproduction 

in Connecticut ospreys was related to contamination of eggs—

namely eggshell thinning and embryo mortality, and not to 

subtle behavioral effects on the incubating parents. Henny 

and Van Velzen (1972) found that ospreys from New York, 

New Jersey, and Maryland shared the same general wintering 
Environmental Contaminant Research Program

Role of Raptors in Contaminant Research at Patuxent 113

Table 4. A, Breeding population changes and, B, productivity of ospreys along the North Atlantic Coast of the United States, 1945–75. 

[Modified from Henny (1977); see Henny (1977) for more information, including citations for publications; >, greater than; NA, not available]

A. Breeding population changes of ospreys

Location Number of occupied nests

Pre-1945 1960 1965 1970 1975

Gardiner’s Island, New York 300 100 70 38 31

Connecticut River, Connecticut 200 71 13 4 1

Rhode Island 130 > 60 23 7 8

Total 630 > 231 106 49 40

Observed annual rate change (percent) -6.5 -14.4 -14.3 -4.0

B. Productivity of ospreys

Location Number of young fledged per occupied nest

1950–52 1953–57 1958–62 1963–67 1968–72 1973–75

Gardiner’s Island, New York 1.19 0.83 0.75 0.16 0.53 0.68

Connecticut River, Connecticut NA 0.37 0.23 0.33 0.25 0.00

Rhode Island NA NA 0.27 0.40 0.61 1.00

Total 1.19 0.65 0.47 0.23 0.52 0.73

Figure 1. A cartoon of the early 1970s, which depicts the Patuxent Wildlife 

Research Center osprey egg exchange. (Cartoon by John L. Carter, a friend of the 

author, and used with his permission.)
114 The History of Patuxent: America’s Wildlife Research Story

grounds, which implied that local breeding success of an 

osprey population depended on environmental conditions 

in the breeding area. Their hypothesis was supported by the 

results of the egg exchanges, including the differences in OC 

residues in fish from the two osprey breeding areas. Average 

eggshell thickness of osprey eggs collected from Connecticut 

had declined 18 percent from pre-1947 norms, whereas that of 

eggs from Maryland had declined 10 percent (Wiemeyer and 

others, 1975).

In the late 1960s and early 1970s, the vision of the 

USFWS, including the MBPS located at Patuxent, was broadening to species other than migratory game species. Planes and 

experienced pilots were available for aerial surveys of nongame species if they did not conflict with breeding and wintering grounds waterfowl surveys. Therefore, the first USFWS 

aerial survey of nesting ospreys was conducted in Chesapeake 

Bay in 1973 (Henny and others, 1974). The survey was 

conducted much like a breeding ground survey of waterfowl 

with a double-sampling approach (both an overall air survey 

covering the entire area and ground surveys in a portion of 

the larger aerial survey area); this approach provided a total 

population estimate and its associated variance. Before the 

survey, both Chan Robbins (long-time Patuxent ornithologist) 

and Alexander Wetmore (long-time Smithsonian Institution 

ornithologist) believed that about 200 to 400 pairs of ospreys 

were nesting in Chesapeake Bay (Chandler Robbins, U.S. Fish 

and Wildlife Service, oral commun., 1973; Alexander Wetmore, Smithsonian Institution, oral commun., 1973), but the 

survey results indicated the estimated population in 1973 to be 

1,450 pairs (Henny and others, 1974).

The Chesapeake Bay study was extended to the coastal 

Carolinas the next year (1974), and was followed in 1975 by 

studies of coastal New Jersey, Delaware, Maryland, and Virginia (Henny and Noltemeier, 1975; Henny and others, 1977). 

Similar osprey surveys were conducted in northern California 

in 1975, Oregon in 1976, and coastal northwestern Mexico 

(Baja California, Gulf of California, Sonora, and Sinaloa) in 

1977 (Henny and others, 1978a, 1978b; Henny and Anderson, 

1979). These surveys provided base values for future population comparisons.

Upon my return to Patuxent following the Carolina 

survey in 1974, I mentioned to Fran Uhler (long-time Patuxent 

biologist) that 38 pairs of ospreys were nesting in relatively 

short bald cypress trees (Taxodium distichum) in the lake at 

Mattamuskeet National Wildlife Refuge. Fran explained that 

the lake had been drained in 1914 to convert it to farmland, 

but the plan was later abandoned. Consequently, the lakebed 

was dry in 1928 when he surveyed it as a possible refuge site. 

In 1934, the U.S. Government acquired the land and a refuge 

was established. Increment borings of the cypress trees used 

as nest sites in 1974 placed their ages at 30 to 40 years, which 

corresponds to the period shortly after the land was acquired 

and reflooding began (Fran Uhler, U.S. Fish and Wildlife Service, oral commun., 1974).

By 1975, osprey populations had been studied at many 

locations and a review of research, management, and status of 

the osprey in North America was presented at the First World 

Birds of Prey Conference in Vienna, Austria (Henny, 1977). 

Declining populations and low productivity were apparent at 

many locations, but with an indication that productivity was 

improving. Later, Wiemeyer and others (1988) reported that 

15 percent and 20 percent eggshell thinning of osprey eggs 

was associated with 4.2 and 8.7 ppm wet weight (ww) DDE, 

respectively. Lincer (1975) reported that no North American 

raptor population that exhibited 18 percent or more eggshell 

thinning was able to maintain a stable population. In later 

years, the percentage of eggs with greater than 4.2 and greater 

than 8 ppm DDE ww (the latter value more closely approximating 18 percent thinning) was used to evaluate DDE effects 

on osprey reproduction. Reproduction rate information (based 

on nests with one egg randomly collected and chemically analyzed) further supported these classifications of contaminant 

effects (Henny and others, 2004). Wiemeyer and others (1975) 

suspected that dieldrin may have increased the mortality rate 

of adult ospreys in Connecticut, and reported a lethal concentration in the brain of an adult male that died in 1967. Another 

adult osprey in South Carolina was believed to have been 

poisoned by dieldrin in 1970 (Wiemeyer and others, 1980). 

None of 29 dead ospreys evaluated (1964–73) died of DDE 

poisoning. The Connecticut population appeared to decline 

more rapidly (from 71 pairs in 1960 to 31 pairs in 1961) than 

reproductive failure alone would predict; however, this precipitous decline may be at least partly explained, as suggested by 

Henny and Ogden (1970), by catastrophic mortality associated 

with the occurrence of the worst hurricane in decades (Donna) 

in September 1960, during the osprey’s fall migration.

By 1981, a nationwide osprey nesting population estimate resulted in a count of approximately 8,000 pairs (Henny, 

1983). Another nationwide population estimate, made in 

1994, showed a 77.5-percent increase (to about 14,200 pairs; 

Houghton and Ryman, 1997), and a similar survey in 2001 

indicated an approximate 25-percent increase (about 16,000–

19,000 pairs; Poole and others, 2002). The initial survey in 

northwestern Mexico in 1977 (810 pairs) was followed by 

others during 1992–93 (1,362 pairs) and 2006 (1,343 pairs) 

(Henny and others, 2008). The increase in osprey eggshell 

thickness following the 1972 ban of DDT in the United States 

was reported in a study with a large series of 238 eggs collected in the Pacific Northwest from 1973 to 2008 (fig. 2; 

Henny and others, 2010).

Many of the OC pesticide, polychlorinated biphenyl 

(PCB), dioxin, and furan concentrations in osprey eggs 

decreased by the end of the 20th century; the decrease in residues resulted in limited or no adverse effects on populations, 

except in a few localized areas (Henny and others, 2010). 

Thus, the osprey, now with large, widely distributed populations again (at lakes, rivers, bays, and estuaries), provides 

a means of evaluating emerging contaminants with limited 

potential for confounding effects from the “legacy” group of 

contaminants (the “old” OCs). Newer contaminants, such as 

polybrominated diphenyl ethers (PBDEs), are widely used 

as flame retardants in thermoplastics, textiles, polyurethane 
Environmental Contaminant Research Program

Role of Raptors in Contaminant Research at Patuxent 115

0.001 0.01 0.10 1 10 100

0.65

0.60

0.55

0.50

0.45

0.40

0.35

Eggshell thickness, in millimeters

DDE concentration, in parts per million, wet weight (log10)

EXPLANATION

Year collected

1973–86

1993–99

2000–08

y = 0.492 – 0.042x

r 2

 = 0.2021

P < 0.0001, n = 238

Figure 2. Semilogarithmic relation between dichlorodiphenyldichloroethylene (DDE) concentration in the egg and eggshell 

thickness in osprey eggs collected from the Pacific Northwest (Oregon, Washington, Idaho), 1972–2008. (Modified from Henny 

and others, 2010)

foams, and electronic circuitry. PBDEs have been reported in 

osprey eggs from Delaware, Maryland, Virginia, Oregon, and 

Washington (Rattner and others, 2004; Toschik and others, 

2005; Henny and others, 2009a). In contrast to the legacy contaminants, PBDEs have increased in the biota since the 1970s, 

and, as concentrations increased above 1 ppm ww, there was 

some evidence of reduced osprey productivity (Henny and 

others, 2009a). More recently, wastewater-treatment-plant 

discharge, a known source of PBDEs (and also an indication 

of human population size at a location), was added to stream 

discharge (both converted to millions of gallons per day) in 

a novel approach (namely an approximate dilution index) to 

relate concentrations of waterborne contaminants to levels of 

these contaminants that reach osprey eggs (Henny and others, 

2011). This simple approach improved understanding of the 

spatial patterns of the contaminants observed in osprey eggs. 

Other emerging contaminants found in osprey eggs since 2000 

included perfluorinated acids and sulfonate compounds in the 

Eastern United States (Rattner and others, 2004; Toschik and 

others, 2005) and the chlorophenoxy herbicide DCPA (trade 

name Dacthal®) and the fungicide chlorothalonil in Puget 

Sound, WA (Chu and others, 2007). The osprey has played 

the role of a worldwide “sentinel species” for contaminant 

investigations. The species characteristics that make it so 

useful for this purpose were recently reviewed by Grove and 

others (2009). 

Bald Eagle

Tissues from field-collected bald eagles and eggs were 

analyzed for pesticide residue content at Patuxent as part of 

the National Pesticide Monitoring Program; the first eagle 

carcass collected was obtained in 1960 (Coon and others, 

1970). A limited number of carcasses were available for 

earlier years, but substantial numbers (692 carcasses) became 

available from 1966 to 1981 and routinely were analyzed 

for a series of contaminants; each report included a diagnosis for cause of death. Reports that included the raw data 

were published regularly by Patuxent scientists. A review of 

these Patuxent bald eagle data (see Peakall [1996], which 

includes diagnostic criteria developed at Patuxent) indicated 

that OC insecticides, especially the cyclodienes like dieldrin, 

killed eagles. The percentage of bald eagle deaths reported 

in the Patuxent literature and attributed to dieldrin poisoning 

decreased after 1970 (that is, 13 percent, 1966–70; 6.5 percent, 

1971–74; 3.0 percent, 1975–77; and 1.7 percent, 1978–81). 

The use of dieldrin plus aldrin (which is metabolized to 

dieldrin) peaked in the United States in 1966 and 1967, and 

was banned by the U.S. Environmental Protection Agency 

for nearly all purposes in 1974 (Nisbet, 1988). Other causes 

of death from contaminants in bald eagles that were reported 

in papers published by Patuxent scientists and reviewed by 

Peakall (1996) included lead, thallium in poisoned bait, DDE 

and metabolites, and perhaps PCBs and endrin.

Because bald eagles are sensitive to human visits early in 

the nesting cycle, most bald eagle eggs were collected after the 

nest failed. This practice is in contrast to the random collection 

of fresh eggs from the osprey, which is more tolerant of human 

activity at its nest early in the nesting cycle. Bald eagle eggs 

were collected in 14 states from 1969 to 1979 (Wiemeyer and 

others, 1984) and 15 states from 1980 to 1984 (Wiemeyer and 

others, 1993). Bald eagle productivity appeared normal when 

eggs contained less than 3.6 ppm ww DDE, but decreased at 

higher concentrations. The largest series of eggs was collected 

in Wisconsin, Maine, Maryland, and Virginia; DDE residues 

declined substantially from 1969 to 1984 in all four states.
116 The History of Patuxent: America’s Wildlife Research Story

Uniqueness of the Patuxent Approach 

Patuxent could conduct controlled laboratory studies, had a large chemistry section to measure contaminant 

levels, and had several field stations pursuing investigations 

throughout the United States; these characteristics resulted 

in a robust combined approach to studying contaminant 

issues and provided a critical number of personnel. The field 

stations often provided initial leads on which contaminants 

to test further in the laboratory. A good example in 1977 

was Warbex (famphur), an OP, used on cattle as a pour-on 

for warble fly control. Black-billed magpies (Pica pica) in 

Oregon were reportedly dying nearby following a topical 

famphur application. The dead magpies were collected and 

frozen by an Oregon Department of Fish and Wildlife biologist in LaGrande, who also happened to be a raptor rehabilitator. During a weekend when he was gone, his wife ran out of 

food for the great horned owl (Bubo virginianus) they were 

rehabilitating. She found a magpie in the freezer and fed it to 

the owl. The owl immediately died. The story was relayed to 

me at the Pacific Northwest field station in Corvallis, OR, and 

a memo was sent to Patuxent. A laboratory study of common 

barn owls fed famphur-exposed quail showed significant cholinesterase (ChE) inhibition. Hill and Mendenhall (1980) concluded that owls could succumb to secondary OP poisoning. 

Then, in 1982, my colleagues and I conducted a field study 

that followed the recommended famphur pour-on treatment of 

535 head of cattle at seven ranches in Washington (Henny and 

others, 1985). Famphur persisted on cow hair for more than 

100 days, and magpies started dying on the day of treatment. 

A red-tailed hawk (Buteo jamaicensis) died 8 to 10 days after 

cattle treatment, and another was found sick 11 to 15 days 

after treatment (both had severe ChE inhibition); the dead 

hawk had eaten a magpie. From March 1984 to March 1985, 

other raptors were tested for famphur and fenthion poisoning 

at Patuxent. The list of deaths attributed to famphur or fenthion included nine bald eagles in four states, three red-tailed 

hawks in two states, and one great horned owl. The eagles and 

hawks had scavenged cattle carcasses or eaten magpies, European starlings (Sturnus vulgaris), or brown-headed cowbirds 

(Molothrus ater) (Franson and others, 1985; Henny and others, 

1987). Before 1982, only two bald eagles had been checked 

at Patuxent for anti-ChE exposure (both negative), but many 

cases remained open (no cause of death determined).

Some Final Thoughts

The number of papers authored by Patuxent scientists 

from 1945 to 2010 dealing with raptors and contaminants 

(142 papers) and raptor population numbers and status 

(58 papers) peaked in the 1980s and declined rather dramatically in later years, after Patuxent lost many of its field stations 

following a 1993 reorganization of the USFWS. Publication 

of raptor contaminant studies at Patuxent started in the early 

1960s; rapidly increased in the 1970s and 1980s, when the 

status and future of many raptor species were of great concern; 

then decreased in later years (fig. 3). Many field station personnel stayed in close contact with their Patuxent colleagues 

and shared information, although their publications were 

counted elsewhere. To address important issues, the Patuxent 

approach involved methods development, combining laboratory and field studies, using the scientific method/experimental 

approach (asking questions and formulating hypotheses), 

1945–1950

1951–19551956–1960

1961–19651966–19701971–1975

1976-1980

1981–19851986–1990

1991–1995

1996–2000

2001–20052006–2010

0

5

10

15

20

25

30

35

Number of papers published

Years

EXPLANATION

Raptors and contaminants 

(Total = 142)

Raptor population and status 

(Total = 58)

Figure 3. Summary of publications dealing with raptors and contaminants and 

raptor population and status, Patuxent Wildlife Research Center, Laurel, MD, 

1945–2010.
Environmental Contaminant Research Program

Role of Raptors in Contaminant Research at Patuxent 117

developing forensic ecotoxicology approaches, and solving 

problems systematically. A unique combination of personnel 

was assembled to address important issues of the time. It was 

a joy to work with them and in the atmosphere at Patuxent 

during those critical years.

Acknowledgments

A list of all raptor publications originating from Patuxent 

Wildlife Research Center (Patuxent), with complete citations, 

is available from the Patuxent library, Laurel, MD (http://

www.pwrc.usgs.gov/library/). Lynda J. Garrett, Patuxent 

librarian, graciously provided me with the list. I thank scientists Dan Anderson (University of California, Davis) and Gary 

H. Heinz (Patuxent), who made valuable comments on the first 

draft that improved the final document.

References Cited

Berger, D.D., Sindelar, C.R., Jr., and Gamble, K.E, 1969, The 

status of breeding peregrines in the eastern United States, 

in Hickey, J.J., ed., Peregrine falcon populations—Their 

biology and decline: Madison, WI, University of Wisconsin 

Press, p. 165–173.

Blus, L.J., 1984, DDE in birds’ eggs—Comparisons of two 

methods for estimating critical levels: Wilson Bulletin, 

v. 96, no. 2, p. 268–276. [Also available at http://sora.unm.

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Broley, C.L., 1958, The plight of the American bald eagle: 

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Buckley, J.L., and DeWitt, J.B., 1963, 1963 progress report—

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W.L., 1970, Causes of bald eagle mortality, 1960–1965: 

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available at http://dx.doi.org/10.7589/0090-3558-6.1.72.]

DeWitt, J.B., 1956, Toxicity of chlorinated insecticides to quail 

and pheasants: Atlantic Naturalist, v. 11, no. 3, p. 115–118.

DeWitt, J.B., and Buckley, J.L., 1962, Studies on pesticideeagle relationships: Audubon Field Notes, v. 16, no. 6, 

p. 541.

Franson, J.C., Kolbe, E.J., and Carpenter, J.W., 1985, Famphur toxicosis in a bald eagle: Journal of Wildlife Diseases, 

v. 21, no. 3, p. 318–320. [Also available at http://dx.doi.

org/10.7589/0090-3558-21.3.318.]

Grove, R.A., Henny, C.J., and Kaiser, J.L., 2009, Osprey—

Worldwide sentinel species for assessing and monitoring 

environmental contamination in rivers, lakes, reservoirs 

and estuaries: Journal of Toxicological and Environmental 

Health, Part B, v. 12, no. 1, p. 25–44. [Also available at 

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Henny, C.J., 1977, Research, management and status of the 

osprey in North America, in Chancellor, R.D., ed., Proceedings World Conference on Birds of Prey: Vienna, 

Austria, International Council for Bird Preservation, 

p. 199–222. [Also available at https://www.researchgate.net/

publication/242505856_Research_management_and_status_

of_the_Osprey_in_North_America_pp199-222.]

Henny, C.J., 1983, Distribution and abundance of nesting 

ospreys in the United States, in Bird, D.M., ed., Biology and 

management of bald eagles and ospreys: Ste. Anne de Bellevue, Quebec, Canada, Harpell Press, p. 175–186.

Henny, C.J., and Anderson, D.W., 1979, Osprey distribution, abundance and status in western North America—III. 

The Baja California and Gulf of California population: 

Bulletin of the Southern California Academy of Sciences, v. 78, no. 2, p. 89–106. [Also available at https://

www.researchgate.net/publication/242464256_Osprey_

distribution_abundance_and_status_in_western_North_

America_III_The_Baja_California_and_Gulf_of_

California_population.]

Henny, C.J., Anderson, D.W., Vera, A.C., and Cartron, J.L., 

2008, Region-wide trends of nesting ospreys in northwestern Mexico—A three decade perspective: Journal of 

Raptor Research, v. 42, no. 4, p. 229–242. [Also available at http://fresc.usgs.gov/products/ProductDetails.

aspx?ProductNumber=2039.]

Henny, C.J., Blus, L.J., Kolbe, E.J., and Fitzner, R.E., 1985, 

Organophosphate insecticide (famphur) topically applied to 

cattle kills magpies and hawks: Journal of Wildlife Management, v. 49, no. 3, p. 648–658. [Also available at http://

dx.doi.org/10.2307/3801689.]
118 The History of Patuxent: America’s Wildlife Research Story

Henny, C.J., Blus, L.J., and Stafford, C.J., 1983, Effects 

of heptachlor on American kestrels in the Columbia 

Basin, Oregon: Journal of Wildlife Management, v. 47, 

no. 4, p. 1080–1087. [Also available at http://dx.doi.org/ 

10.2307/3808167.]

Henny, C.J., Byrd, M.A., Jacobs, J.A., McLain, P.D., Todd, 

M.R., and Halla, B.F., 1977, Mid-Atlantic coast osprey 

population—Present numbers, productivity, pollutant 

contamination, and status: Journal of Wildlife Management, 

v. 41, no. 2, p. 254–265. [Also available at http://dx.doi.org/ 

10.2307/3800602.]

Henny, C.J., Collins, C.A., and Deibert, W.J., 1978a, 

Osprey distribution, abundance, and status in western 

North America—II. The Oregon population: Murrelet, v. 

59, no. 1, p. 14–25. [Also available at http://dx.doi.org/ 

10.2307/3534722.]

Henny, C.J., Dunaway, D.J., Mallette, R.D., and Koplin, J.R., 

1978b, Osprey distribution, abundance and status in western 

North America—I. The northern California population: 

Northwest Science, v. 52, no. 3, p. 261–271. [Also available 

at https://www.researchgate.net/publication/242484358_

Osprey_distribution_abundance_and_status_in_western_

North_America_I_The_northern_California_population.]

Henny, C.J., Grove, R.A., Kaiser, J.L., and Bentley, V.R., 

2004, An evaluation of osprey eggs to determine spatial 

residue patterns and effects of contaminants along the lower 

Columbia River, U.S.A, in Chancellor, R.D., and Meyburg, 

B.-U., eds., Raptors worldwide: Hungary, Budapest, 

World Working Group Birds of Prey and MME/Hungarian 

BirdLife, p. 369–388. [Also available at http://fresc.usgs.

gov/products/ProductDetails.aspx?ProductNumber=1268.]

Henny, C.J., Grove, R.A., Kaiser, J.L., and Johnson, B.L., 

2010, North American osprey populations and contaminants—Historic and contemporary perspectives: Journal of 

Toxicological Environmental Health, part B, v. 13, no. 7–8, 

p. 579–603. [Also available at http://dx.doi.org/10.1080/109

37404.2010.538658.]

Henny, C.J., Grove, R.A., Kaiser, J.L., Johnson, B.L., Furl, 

C.V., and Letcher, R.J., 2011, Wastewater dilution index 

partially explains observed polybrominated diphenyl ether 

flame retardant concentrations in osprey eggs from Columbia River Basin, 2008–2009: Ecotoxicology, v. 20, no. 4, 

p. 682–697. [Also available at http://dx.doi.org/10.1007/

s10646-011-0608-2.]

Henny, C.J., Kaiser, J.L., Grove, R.A., Johnson, B.L., and 

Letcher, R.J., 2009a, Polybrominated diphenyl ether flame 

retardants in eggs may reduce reproductive success of 

ospreys in Oregon and Washington, USA: Ecotoxicology, 

v. 18, no. 7, p. 802–813. [Also available at http://dx.doi.

org/10.1007/s10646-009-0323-4.]

Henny, C.J., Kolbe, E.J., Hill, E.F., and Blus, L.J., 1987, Case 

histories of bald eagles and other raptors killed by organophosphorus insecticides topically applied to livestock: 

Journal of Wildlife Diseases, v. 23, no. 2, p. 292–295. [Also 

available at http://dx.doi.org/10.7589/0090-3558-23.2.292.]

Henny, C.J., and Noltemeier, A.P., 1975, Osprey nesting 

populations in the coastal Carolinas: American Birds, v. 29, 

no. 6, p. 1073–1079. [Also available at https://sora.unm.

edu/node/112542.]

Henny, C.J., and Ogden, J.C., 1970, Estimated status of osprey 

populations in the United States: Journal of Wildlife Management, v. 34, no. 1, p. 214–217. [Also available at http://

dx.doi.org/10.2307/3799513.]

Henny, C.J., Overton, W.S., and Wight, H.M., 1970, Determining parameters for populations by using structural models: 

Journal of Wildlife Management, v. 34, no. 4, p. 690–703. 

[Also available at http://dx.doi.org/10.2307/3799133.]

Henny, C.J., Schmid, F.C., Martin, E.M., and Hood, L.L., 

1973, Territorial behavior, pesticides, and the population 

ecology of red-shouldered hawks in central Maryland, 

1943–1971: Ecology, v. 54, no. 3, p. 545–554. [Also available at http://dx.doi.org/10.2307/1935339.]

Henny, C.J., Smith, M.M., and Stotts, V.D., 1974, The 1973 

distribution and abundance of breeding ospreys in the Chesapeake Bay: Chesapeake Science, v. 15, no. 3, p. 125–133. 

[Also available at http://www.jstor.org/stable/1351027.]

Henny, C.J., and Van Velzen, W.T., 1972, Migration patterns 

and wintering localities of American ospreys: Journal of 

Wildlife Management, v. 36, no. 4, p. 1133–1141. [Also 

available at http://dx.doi.org/10.2307/3799242.]

Henny, C.J., Ward, F.P., Riddle, K.E., and Prouty, R.M., 1982, 

Migratory peregrine falcons (Falco peregrinus) accumulate pesticides in Latin America during winter: Canadian 

Field-Naturalist, v. 96, no. 3, p. 333–338. [Also available at 

http://www.biodiversitylibrary.org/item/89040#page/353/

mode/1up.]

Henny, C.J., and Wight, W.M., 1969, An endangered osprey 

population—Estimates of mortality and production: Auk, 

v. 86, p. 188–198. [Also available at https://sora.unm.edu/

node/21848.]

Henny, C.J., Yates, M.A., and Seegar, W.S., 2009b, Dramatic declines of DDE and other organochlorines in 

spring migrant peregrine falcons from Padre Island, TX, 

1978–2004: Journal of Raptor Research, v. 43, no. 1, 

p. 37–42. [Also available at http://fresc.usgs.gov/products/

ProductDetails.aspx?ProductNumber=2090.]

Hickey, J.J., 1942, Eastern population of the duck hawk: Auk, 

v. 59, p. 176–204. [Also available at https://sora.unm.edu/

node/18329.]
Environmental Contaminant Research Program

Role of Raptors in Contaminant Research at Patuxent 119

Hickey, J.J., 1952, Survival studies of banded birds: Washington, D.C., Special Scientific Report—Wildlife, no. 15, 

177 p. [Also available at https://babel.hathitrust.org/cgi/pt?i

d=mdp.39015077581133;view=1up;seq=3.]

Hickey, J.J., ed., 1969, Peregrine falcon populations—Their 

biology and decline: Madison, WI, University of Wisconsin 

Press, 596 p.

Hickey, J.J., and Anderson, D.W., 1968, Chlorinated hydrocarbons and eggshell changes in raptorial and fish-eating birds: 

Science, v. 162, no. 3850, p. 271–273. [Also available at 

http://www.jstor.org/stable/1725067.]

Hill, E.F., and Mendenhall, V.M., 1980, Secondary poisoning 

of barn owls with famphur, an organophosphate insecticide: 

Journal of Wildlife Management, v. 44, no. 3, p. 676–681. 

[Also available at http://dx.doi.org/10.2307/3808017.]

Hotchkiss, Neil, and Pough, R.H., 1946, Effect on forest birds 

of DDT used for gypsy moth control in Pennsylvania: Journal of Wildlife Management, v. 10, no. 3, p. 202–207. [Also 

available at http://dx.doi.org/10.2307/3795833.]

Houghton, L.M., and Rymon, L.M., 1997, Nesting distribution and population status of U.S. ospreys, 1994: Journal of 

Raptor Research, v. 31, no. 1, p. 44–53. [Also available at 

https://sora.unm.edu/node/53582.]

Lincer, J.L., 1975, DDE-induced eggshell-thinning in the 

American kestrel—A comparison of the field situation and laboratory results: Journal of Applied Ecology, 

v. 12, no. 3, p. 781–793. [Also available at http://dx.doi.

org/10.2307/2402090.]

Martin, E.M., 2004, Decreases in a population of red-shouldered hawks nesting in central Maryland: Journal of Raptor 

Research, v. 38, no. 4, p. 312–319. [Also available at https://

sora.unm.edu/node/54130.]

Mitchell, R.T., Blagbrough, H.P., and Van Etten, R.C., 

1953, The effects of DDT upon the survival and growth 

of nestling songbirds: Journal of Wildlife Management, 

v. 17, no. 1, p. 45–54. [Also available at http://dx.doi.

org/10.2307/3796804.]

Nisbet, I.C.T., 1988, The relative importance of DDE and dieldrin in the decline of peregrine falcon populations, in Cade, 

T.J., Enderson, J.H., Thelander, C.G., and White, C.M., 

eds., Peregrine falcon populations—Their management and 

recovery: Boise, ID, The Peregrine Fund, Inc., p. 351–375.

Peakall, D.B., 1996, Dieldrin and other cyclodiene pesticides 

in wildlife, in Beyer, W.N., Heinz, G.H., and Redmon-Norwood, A.W., eds., Environmental contaminants in wildlife—Interpreting tissue concentrations: Boca Raton, FL, 

Lewis Publishers, p. 73–97.

Peterson, R.T., 1969, Population trends of ospreys in the 

northeastern United States, in Hickey, J.J., ed., Peregrine 

falcon populations—Their biology and decline: Madison, 

WI, University of Wisconsin Press, p. 333–337.

Poole, A.F., Bierregaard, R.O., and Martell, M.S., 2002, 

Osprey (Pandion haliaetus), in Poole, A.F., and Gill, Frank, 

eds., The Birds of North America, issue no. 683: Philadelphia, PA, Birds of North America, Inc.

Porter, R.D., and Wiemeyer, S.N., 1969, Dieldrin and DDT—

Effects on sparrow hawk eggshells and reproduction: Science, v. 165, no. 3889, p. 199–200. [Also available at http://

www.jstor.org/stable/1726452.]

Postupalsky, Sergej, 1969, The status of the osprey in Michigan in 1965, in Hickey, J.J., ed., Peregrine falcon populations—Their biology and decline: Madison, WI, University 

of Wisconsin Press, p. 338–340.

Ratcliffe, D.A., 1967, Decrease in eggshell weight in certain 

birds of prey: Nature, v. 215, no. 5097, p. 208–210. [Also 

available at http://dx.doi.org/10.1038/215208a0.]

Ratcliffe, D.A., 1969, Population trends of the peregrine 

falcon in Great Britain, in Hickey, J.J., ed., Peregrine falcon 

populations—Their biology and decline: Madison, WI, 

University of Wisconsin Press, p. 239–269.

Rattner, B.A., McGowan, P.C., Golden, N.H., Hatfield, J.S., 

Toschik, P.C., Lukei, R.F., Jr., Hale, R.C., Schmitz-Alfonso, 

Isabelle, and Rice, C.P., 2004, Contaminant exposure and 

reproductive success of ospreys (Pandion haliaetus) nesting in Chesapeake Bay regions of concern: Archives of 

Environmental Contaminants and Toxicology, v. 47, no. 1, 

p. 126–140. [Also available at http://dx.doi.org/10.1007/

s00244-003-3160-0.]

Robbins, C.S., 1950, Hawks over Maryland, fall of 1949: 

Maryland Birdlife, v. 6, no. 1, p. 2–11. [Also available at 

https://sora.unm.edu/node/132726.]

Robbins, C.S., 1956, Hawk watch: Atlantic Naturalist, v. 11, 

no. 5, p. 208–217.

Robbins, C.S., 1960, Status of the bald eagle, summer of 

1959: Washington, D.C., U.S. Fish and Wildlife Service, 

Wildlife Leaflet 418, 8 p. [Also available at https://archive.

org/details/statusofbaldeagl418robb.]

Robbins, C.S., Springer, P.F., and Webster, C.G., 1951, Effects 

of five-year DDT application on breeding bird population: 

Journal of Wildlife Management, v. 15, no. 2, p. 213–216. 

[Also available at http://dx.doi.org/10.2307/3796613.]

Robbins, C.S., and Stewart, R.E., 1949, Effects of DDT on 

bird population of scrub forest: Journal of Wildlife Management, v. 13, no. 1, p. 11–16. [Also available at http://dx.doi.

org/10.2307/3796121.]
120 The History of Patuxent: America’s Wildlife Research Story

Rudd, R.L., 1964, Pesticides and the living landscape: Madison, WI, University of Wisconsin Press, 320 p.

Schmid, F.C., 1966, The status of the osprey in Cape May 

County, New Jersey, between 1939 and 1963: Chesapeake 

Science, v. 7, no. 4, p. 220–223. [Also available at http://

www.jstor.org/stable/1350442.]

Spitzer, P.L., Poole, A.F., and Scheibel, M.S., 1983, Initial 

recovery of breeding ospreys in the region between New 

York City and Boston, in Bird, D.M., ed., Biology and management of bald eagles and ospreys: Ste. Anne de Bellevue, 

Quebec, Canada, Harpell Press, p. 231–241.

Stewart, R.E., 1949, Ecology of a nesting red-shouldered 

hawk population: Wilson Bulletin, v. 61, no. 1, p. 26–35. 

[Also available at http://sora.unm.edu/node/126881.]

Stewart, R.E., Cope, J.B., and Robbins, C.S., 1945, Live 

trapping of hawks and owls: Journal of Wildlife Management, v. 9, no. 2, p. 99–104. [Also available at http://dx.doi.

org/10.2307/3795888.]

Stewart, R.E., Cope, J.B., Robbins, C.S., and Brainerd, 

J.W., 1946, Effects of DDT on birds at Patuxent Wildlife Research Refuge: Journal of Wildlife Management, 

v. 10, no. 3, p. 195–201. [Also available at http://dx.doi.

org/10.2307/3795832.]

Stickel, L.F., Chura, N.J., Stewart, P.A., Menzie, C.M., Prouty, 

R.M., and Reichel, W.L., 1966, Bald eagle pesticide relations: Transactions of the North American Wildlife and 

Natural Resources Conference, v. 31, p. 190–200.

Stickel, L.F., Schmid, F.C., Reichel, W.L., and Ames, P.L., 

1965, Ospreys in Connecticut and Maryland: Washington, 

D.C., U.S. Fish and Wildlife Service, Circular 226, p. 4–6.

Stickel, W.H., Stickel, L.F., and Coon, F.B., 1970, DDE and 

DDD residues correlated with mortality in experimental 

birds, in Deichmann, W.B., ed., Pesticides symposia—

Seventh Inter-American Conference on Toxicology and 

Occupational Medicine: Miami, FL, Helios and Associates, 

p. 287–294.

Stickel, W.H., Stickel, L.F., and Spann, J.W., 1969, Tissue 

residues of dieldrin in relation to mortality in birds and 

mammals, in Miller, M.W., and Berg, G.G., eds. Chemical 

fallout—Current research on persistent pesticides: Springfield, IL, Charles C. Thomas, p. 174–204.

Stickel, L.F., Wiemeyer, S.N., and Blus, L.J., 1973, Pesticide 

residues in eggs of wild birds—Adjustment for loss of 

moisture and lipid: Bulletin of Environmental Contamination and Toxicology, v. 9, no. 4, p. 193–196. [Also available 

at http://dx.doi.org/10.1007/BF01684824.]

Toschik, P.C., Rattner, B.A., McGowan, P.C., Christman, 

M.C., Carter, D.B., Hale, R.C., Matson, C.W., and Ottinger, 

M.A., 2005, Effects of contaminant exposure on reproductive success of ospreys (Pandion haliaetus) nesting in 

Delaware River and Bay, USA: Environmental Toxicology 

and Chemistry, v. 24, no. 3, p. 617–628. [Also available at 

http://dx.doi.org/10.1897/04-141R.1.]

Wiemeyer, S.N., Bunck, C.M., and Krynitsky, A.J., 1988, 

Organochlorine pesticides, polychlorinated biphenyls and 

mercury in osprey eggs—1970–1979—and their relationships to shell thinning and productivity: Archives of 

Environmental Contamination and Toxicology, v. 17, no. 

6, p. 767–787. [Also available at http://dx.doi.org/10.1007/

BF01061982.]

Wiemeyer, S.N., Bunck, C.M., and Stafford, C.J., 1993, Environmental contaminants in bald eagle eggs—1980–84—and 

further interpretations of relationships to productivity and 

shell thickness: Archives of Environmental Contamination 

and Toxicology, v. 24, no. 2, p. 213–227. [Also available at 

http://dx.doi.org/10.1007/BF01141351.]

Wiemeyer, S.N., Lamont, T.G., Bunck, C.M., Sindelar, C.R., 

Gramlich, F.J., Fraser, J.D., and Byrd, M.A., 1984, Organochlorine pesticide, polychlorobiphenyl and mercury residues 

in bald eagle eggs—1969–79—and their relationships to 

shell thinning and reproduction: Archives of Environmental 

Contamination and Toxicology, v. 13, no. 5, p. 529–549. 

[Also available at http://dx.doi.org/10.1007/BF01056332.]

Wiemeyer, S.N., Lamont, T.G., and Locke, L.N., 1980, 

Residues of environmental pollutants and necropsy data for 

eastern United States ospreys, 1964–1973: Estuaries, v. 3, 

no. 3, p. 155–167. [Also available at http://www.jstor.org/

stable/1352065.]

Wiemeyer, S.N., and Porter, R.D., 1970, DDE thins eggshells of captive American kestrels: Nature, v. 227, 

no. 5259, p. 737–738. [Also available at http://dx.doi.

org/10.1038/227737a0.]

Wiemeyer, S.N., Porter, R.D., Hensler, G.L., and Maistrelli, 

J.R., 1986, DDE, DDT + dieldrin—Residues in American 

kestrels and relations to reproduction: Washington, D.C., 

U.S. Fish and Wildlife Service, Fish and Wildlife Technical 

Report 6, 33 p.

Wiemeyer, S.N., Spitzer, P.R., Krantz, W.C., Lamont, T.G., 

and Cromartie, Eugene, 1975, Effects of environmental 

pollutants on Connecticut and Maryland ospreys: Journal of 

Wildlife Management, v. 39, no. 1, p. 124–139. [Also available at http://dx.doi.org/10.2307/3800475.]
Environmental Contaminant Research Program

Research on Amphibians and Reptiles at Patuxent: 

A Synopsis

By Donald W. Sparling

Patuxent Wildlife Research Center (Patuxent) in Laurel, 

MD, has a long history of research on amphibians and reptiles, 

beginning long before such research became commonplace. 

A survey of the Patuxent bibliography revealed 385 papers, 

books, or book chapters written or cowritten by Patuxent scientists from 1942 to 2015. Patuxent scientists are authors on 

231 publications on amphibians, 226 publications on reptiles, 

and 36 publications that included both classes.

These papers cover a wide range of topics, including contaminants, systematics, general ecology, sampling techniques, 

and disease (fig. 1). Notably, papers on amphibians and 

reptiles are nearly equal in number, in contrast to the literature 

as a whole, where papers on amphibians far outnumber papers 

on reptiles.

The oldest paper in the Patuxent bibliography on herpetofauna was published by biologist William Stickel in 1942 

(Stickel, 1942). Bill’s wildlife career at Patuxent in the early 

1940s was only partially interrupted when he was drafted into 

the Army during World War II. While in New Guinea and the 

Philippines, he found time to pursue his biological interests. 

He collected a variety of specimens, several of which were 

140

120

100

80

60

40

20

0

Number of publications

Total

Contaminants

Systematics

Ecology

Sampling

Disease

Category

EXPLANATION

Amphibian

Reptile

Figure 1. Number of publications on amphibians and reptiles 

authored by Patuxent Wildlife Research Center scientists, 

1942–2011, by category.

later found to be new to science. A species of lizard (Sphenomorphus stickeli) from New Guinea (Loveridge, 1948) and 

a frog (Kaloula stickeli) from the Philippines (Inger, 1954) 

were named in his honor (Stickel, 1996; Perry, 2007, p. 259). 

Patuxent biologist Francis Uhler was also active in providing 

information about snakes in the 1940s (Uhler, 1944). Uhler 

also conducted a food habits study with snakes in the George 

Washington National Forest in Virginia just prior to coming to 

Patuxent (Uhler and others, 1939).

Mr. Stickel and his wife, Dr. Lucille Stickel, were prolific 

writers in the 1940s and 1950s. Dr. Stickel published several 

papers on the ecology and movements of eastern box turtles 

(Terrapene carolina), and all of her research was done at 

Patuxent (Stickel, 1950, 1978). Her study on box turtles was 

continued for approximately 60 years by several biologists 

and is a highly cited classic (Hall and others, 1999). Patuxent biologist Paula Henry did the most recent field work 

on this subject, and published reviews of the work in 2003 

(Henry, 2003).

Research on herpetofauna was at a low during the 1960s 

and 1970s, but increased dramatically during the 1980s, 

primarily because of the work of three Patuxent scientists, 

Thomas H. Fritts, Russell J. Hall, and Robert P. Reynolds. 

Tom Fritts was a herpetologist at the Museum of Natural 

History, Washington, D.C., one of the field stations of Patuxent. He and Gordon Rodda wrote extensively on the invasive 

brown tree snake (Boiga irregularis), its effects on native 

populations of birds on Guam, and its threat to other Pacific 

Islands (Fritts, 1988; Rodda and others, 1991). Fritts also 

studied sea turtles and published papers on their distribution, 

ecology, and exposure to contaminants (Fritts, 1981).

Russ Hall was a major contributor of herpetofauna 

research during the 1980s, and an early pioneer in the area of 

amphibian and reptile ecotoxicology. Studies were published 

on the effects and uptake of pesticides, polychlorobiphenyls 

(PCBs), metals, polycyclic aromatic hydrocarbons (PAHs), 

and organochlorines on anurans (frogs and toads), salamanders, lizards, sea turtles, and other reptiles (Hall, 1988; Hall 

and Coon, 1988; Hall and Henry, 1992). Another contaminant 

study on herpetofauna was conducted by Peter Albers, who 

studied survival of spotted salamander (Ambystoma maculatum) eggs in temporary woodland ponds (Albers and Prouty, 
122 The History of Patuxent: America’s Wildlife Research Story

1987) and contaminants in snapping turtles (Chelydra serpentina) in a tidal wetland (Albers and others, 1986). Patuxent researcher Gary H. Heinz studied contaminant levels in 

alligators (Alligator mississippiensis) in Florida (Heinz and 

others, 1991) and in snakes in Lake Michigan (Heinz and 

others, 1980).

During the 1990s, the National Biological Survey (later 

the National Biological Service) (NBS) was formed from 

research entities within the U.S. Department of the Interior 

(DOI), and vertebrate biologists from the National Museum 

of Natural History of the Smithsonian Institution joined the 

Patuxent staff. This collaboration resulted in an extensive 

series of publications on the distribution and systematics of 

amphibians and reptiles under the Patuxent banner. Patuxent 

researcher Roy McDiarmid published three books on tadpoles 

in collaboration with Ronald Altig (McDiarmid and Altig, 

1999; Altig and McDiarmid, 2015; Altig and others, 1998). 

McDiarmid also published several descriptions of amphibian 

taxa as peer-reviewed articles or book chapters, and with other 

Patuxent scientists published the widely used references for 

the inventory and monitoring of amphibian (Heyer and others, 

1994) and reptile (McDiarmid and others, 2012) biodiversity. 

As a coauthor with colleagues, McDiarmid also wrote a monograph on the history of herpetologists and herpetology in the 

DOI (Lovich and others, 2012).

A colleague of McDiarmid, Bob Reynolds, station 

leader of the Patuxent Biological Survey Unit at the National 

Museum of Natural History, conducted surveys of amphibians 

and reptiles throughout northern South America in Bolivia, 

Ecuador, Guyana, and Peru. In 2005, he collaborated with 

Tom Hollowell on a checklist of the terrestrial vertebrates of 

the Guyana Shield (Hollowell and Reynolds, 2005); more 

recently, he collaborated on a monograph on the amphibians 

and reptiles of Guyana (Cole and others, 2013). In addition, 

he published a number of regional herpetological surveys 

throughout Guyana (MacCulloch and others, 2007; MacCulloch and Reynolds, 2012; Reynolds and MacCulloch, 2012; 

MacCulloch and Reynolds, 2013). Reynolds also published 

peer-reviewed descriptions of new species for four amphibians and three snakes (Reynolds and Foster, 1992; Wynn and 

others, 2012).

Patuxent biologist Matthew Perry monitored amphibians 

and reptiles with pitfall and funnel traps set along drift fences 

on mitigated forested wetlands (fig. 2). These studies revealed 

that the wood frog (Rana sylvatica) was the only amphibian species found in reference forested wetlands, but not in 

adjacent mitigated sites (Perry and others, 1996, 2001). Perry 

also monitored amphibians and reptiles to evaluate five habitat 

management practices on a powerline right-of-way (Perry and 

others, 1997).

Figure 2. Pitfall and funnel traps along drift fence to capture amphibians and reptiles sampled by Brian Eyler, 

U.S. Geological Survey, as part of forested wetland mitigation study, 1996. Photo by Matthew C. Perry, U.S. 

Geological Survey.
Environmental Contaminant Research Program

Research on Amphibians and Reptiles at Patuxent: A Synopsis 123

During the 2000s, research, especially on amphibians, 

expanded into multiple areas because of the publication of 

papers resulting from the U.S. Geological Survey (USGS) 

Amphibian Research and Monitoring Initiative (ARMI), the 

Patuxent North American Amphibian Monitoring Program 

(NAAMP), and other ongoing studies. The ARMI was started 

in 2000, after the NBS became part of the U.S. Geological 

Survey (Muths and others, 2005). Its mission was to monitor amphibian populations and investigate probable causes of 

amphibian declines (Corn and others, 2005). Robin Jung, the 

first Northeast ARMI coordinator, collaborated with biostatisticians at Patuxent to improve methods of surveying and 

sampling amphibians. Patuxent biologists Larissa Bailey and 

Evan Grant subsequently led the Northeast ARMI program at 

Patuxent. Some examples of ARMI research include vernal pool egg mass counts and the study of potential climate 

change effects on the endangered Shenandoah salamanders 

(Plethodon shenandoah) in Virginia (Jung and others, 2005).

The NAAMP, initiated by Patuxent biologist Sam 

Droege, later was led by Patuxent biologist Linda Weir, who 

was followed by Evan Grant. It is a large-scale monitoring program consisting of more than 500 volunteers in more 

than 20 states collecting data to assess frog population trends 

(Weir and Mossman, 2005). This book chapter by Weir and 

Mossman describes the NAAMP protocol and partnership. 

Droege was also instrumental in developing Frogwatch USA, 

a citizen-based science program for people to monitor their 

backyard pond or neighborhood wetland. The program was 

transferred to the National Wildlife Federation and is now 

(2016) coordinated by the Association of Zoos and Aquariums 

(accessed May 21, 2015, at https://www.aza.org/frogwatch/). 

Additional key USGS scientists in this area included Jim 

Hines, Bill Kendall, Jim Nichols, Andy Royle, and John Sauer 

(MacKenzie and others, 2002).

Investigations on contaminants continued during the 

2000s with my work, which focused on effects of pesticides on 

amphibians in the Sierra Nevada of California, and the effects 

of variety of pesticides, acidification, metals, perchlorate, 

and sediment-borne lead on amphibians (Sparling and others, 

2000; Linder and others, 2003a; Linder and others, 2003b). 

Patuxent biologist Mark Melancon focused on biomarkers. 

Patuxent scientists J. Michael Meyers, Jeff Hatfield, Robin 

Jung, Priya Nanjappa, and Jerry Longcore studied the conservation of amphibians and reptiles (Hatfield and others, 2004; 

Whiting and others, 2004, Jung and others, 2005). Longcore 

and others (2006) surveyed anurans in the northeastern United 

States to determine the distribution of chytridiomycosis, a 

lethal disease in some species of amphibians.

Productivity at Patuxent in terms of publications on 

amphibians and reptiles has generally increased since the 

1950s (fig. 3) and continues to increase. Approximately 

20 new papers were published during the first 18 months of 

2010–11; at that rate, more than 125 papers would be published during the decade from 2010–19. The collaborators on 

these projects number more than 100, and contributions have 

been received from colleagues from all over the United States 

and several foreign countries.

Major Contributions of Research by 

Patuxent Scientists

Over the years, research on amphibians and reptiles has 

focused on natural history, contaminants, systematics, sampling methodology, distribution, and conservation. Major 

contributions of Patuxent scientists to research on amphibians 

and reptiles include—

• New and improved methodologies to survey and 

accurately estimate the size of amphibian and reptile 

populations;

100

80

60

40

20

0

Number of publications

Decade

Pre-1960s 1960s 1970s 1980s 1990s 2000s

Figure 3. Number of publications on amphibians and reptiles 

published by Patuxent Wildlife Research Center scientists, 

by decade.
124 The History of Patuxent: America’s Wildlife Research Story

• Information on the accumulation and effects of many 

environmental contaminants, including mercury, 

organophosphate pesticides, lead, perchlorate, ammonium, toxaphene, endrin, PCBs, and methoxychlor, 

as well as multiple stressors, on amphibians;

• Increased knowledge about the effects of PAHs, 

dicofol, dichlorodiphenyltrichloroethane (DDT), 

dichlorodiphenyldichloroethylene (DDE), 

organochlorines, aldrin, petroleum, organophosphate 

pesticides, and mercury on reptiles;

• North American Amphibian Monitoring Program, 

developed by using the Breeding Bird Survey 

as a model;

• Information on the ecology, distribution, and conservation needs of many species of amphibians and 

reptiles;

• Early warning about and studies of the invasive brown 

tree snake before and during its devastation of avifauna on Guam;

• Input to and guidance on the formation of the Amphibian Research and Monitoring Initiative;

• Important research and conservation guidelines 

for endangered sea turtles;

• Assistance in the creation of Frogwatch USA, a 

citizen-based program to monitor amphibians; and

• A more than 60-year-long investigation of the population dynamics of eastern box turtles, one of the 

longest studies ever conducted on a single species.

Selected References

Albers, P.H., and Prouty, R.M., 1987, Survival of spotted 

salamander eggs in temporary woodland ponds of coastal 

Maryland: Environmental Pollution, v. 46, no. 1, p. 45–61. 

[Also available at http://dx.doi.org/10.1016/0269-

7491(87)90144-8.]

Albers, P.H., Sileo, Louis, and Mulhern, B.M., 1986, Effects 

of environmental contaminants on snapping turtles of a 

tidal wetland: Archives of Environmental Contamination 

and Toxicology, v. 15, no. 1, p. 39–49. [Also available at 

http://dx.doi.org/10.1007/BF01055247.]

Altig, Ronald, and McDiarmid, R.W., 2015, Handbook of 

larval amphibians of the United States and Canada: Ithaca, 

NY, Cornell University Press, 345 p.

Altig, Ronald, McDiarmid, R.W., Nichols, K.A., and Ustach, 

P.C., 1998, A key to the anuran tadpoles of the United 

States and Canada: Contemporary Herpetology Information 

Series 2, p. 1–58.

Cole, C.J., Townsend, C.R., Reynolds, R.P., MacCulloch, 

R.A., and Lathrop, Amy, 2013, Amphibians and reptiles 

of Guyana, South America—Illustrated keys, annotated species accounts, and a biogeographic synopsis: 

Proceedings of the Biological Society of Washington, 

v. 125, no. 4, p. 317–620. [Also available at http://dx.doi.

org/10.2988/0006-324X-125.4.317.]

Corn, P.S., Adams, M.J., Battaglin, W.A., Gallant, A.L., James, 

D.L., Knutson, Melinda, Langtimm, C.A., and Sauer, J.R., 

2005, Amphibian Research and Monitoring Initiative—Concepts and implementation: U.S. Geological Survey Scientific Investigations Report 2005–5015, 23 p. [Also available 

at https://pubs.er.usgs.gov/publication/5230279.]

Fritts, T.H., 1981, Marine turtles of the Galápagos Islands and 

adjacent areas of the eastern Pacific on the basis of observations made by J.R. Slevin 1905–1906: Journal of Herpetology, v. 15, no. 3, p. 293–301. [Also available at http://

dx.doi.org/10.2307/1563432.]

Fritts, T.H., 1988, The brown tree snake, Boiga irregularis, a 

threat to Pacific Islands: Washington, D.C., U.S. Fish and 

Wildlife Service Biological Report, v. 88, no. 31, 36 p. 

[Also available at https://babel.hathitrust.org/cgi/pt?id=mdp

.39015086474775;view=1up;seq=3.]

Hall, R.J., 1994, Herpetofaunal diversity of the Four 

Holes Swamp, South Carolina: Washington, D.C., 

National Biological Survey, Resource Publication 198, 

45 p. [Also available at http://www.dtic.mil/cgi-bin/

GetTRDoc?AD=ADA322610.]

Hall, R.J., and Coon, N.C., 1988, Interpreting residues of 

petroleum hydrocarbons in wildlife tissues: Washington, 

D.C., U.S. Fish and Wildlife Service, Biological Report 88, 

15 p. [Also available at http://www.pwrc.usgs.gov/oilinla/

pdfs/3610_Hall.pdf.]

Hall, R.J., and Henry, P.F.P., 1992, Assessing effects of pesticides on amphibians and reptiles—Status and needs: Herpetological Journal, v. 2, p. 65–71. [Also available at https://

www.researchgate.net/publication/263008772_Assessing_effects_of_pesticides_on_amphibians_and_reptiles_status_and_needs_Herpetol_J_2365-71.]

Hall, R.J., Henry, P.F.P., and Bunck, C.M., 1999, Fifty-year 

trends in a box turtle population in Maryland: Biological 

Conservation, v. 88, no. 2, p. 165–172. [Also available at 

http://dx.doi.org/10.1016/S0006-3207(98)00107-4.]
Environmental Contaminant Research Program

Research on Amphibians and Reptiles at Patuxent: A Synopsis 125

Hatfield, J.S., Price, A.H., Diamond, D.D., and True, C.D., 

2004, Houston toad (Bufo houstonensis) in Bastrop County, 

Texas—Need for protecting multiple subpopulations, in

Akçakaya, H.R., Burgman, M.A., Kindvall, Oskar, Wood, 

C.C., Sjögren-Gulve, Per, Hatfield, J.S., and McCarthy, 

M.A., eds., Species conservation and management—

Case studies: Oxford, England, Oxford University Press, 

p. 292–298.

Heinz, G.H., Haseltine, S.D., Hall, R.J., and Krynitsky, A.J., 

1980, Organochlorine and mercury residues in snakes from 

Pilot and Spider Islands, Lake Michigan—1978: Bulletin of 

Environmental Contamination and Toxicology, v. 25, no. 5, 

p. 738–743. [Also available at http://dx.doi.org/10.1007/

BF01985601.]

Heinz, G.H., Percival, H.F., and Jennings, M.L., 1991, Contaminants in American alligator eggs from Lake Apopka, 

Lake Griffin, and Lake Okeechobee, Florida: Environmental 

Monitoring and Assessment, v. 16, no. 3, p. 277–285. [Also 

available at http://dx.doi.org/10.1007/BF00397615.]

Henry, P.F.P., 2003, The eastern box turtle at the Patuxent 

Wildlife Research Center 1940s to the present—Another 

view: Experimental Gerontology, v. 38, no. 7, p. 773–776. 

[Also available at http://dx.doi.org/10.1016/S0531-

5565(03)00107-4.]

Heyer, W.R., Donnelly, M.A., McDiarmid, R.W., Hayek, L.C., 

and Foster, M.S., eds., 1994, Measuring and monitoring 

biological diversity—Standard methods for amphibians: 

Washington, D.C., Smithsonian Institution Press, 384 p.

Hollowell, Tom, and Reynolds, R.P., eds., 2005, Checklist 

of the terrestrial vertebrates of the Guiana Shield: Bulletin of the Biological Society of Washington, no. 13, 106 

p. [Also available at http://www.pwrc.usgs.gov/prodabs/

ab04060906/6484_Hollowell.pdf.]

Inger, R.F., 1954, Systematics and zoogeography of Philippine Amphibia: Fieldiana Zoology, v. 33, no. 4, 

p. 183–531. [Also available at https://archive.org/details/

systematicszooge334inge.]

Jung, R.E., Royle, J.A., Sauer, J.R., Addison, C., Rau, R.D., 

Shirk, J.L., and Whissel, J.C., 2005, Estimation of stream 

salamander (Plethodontidae, Desmognathinae, and Plethodontinae) populations in Shenandoah National Park, Virginia, 

USA: Alytes, v. 22, no. 3–4, p. 72–84.

Linder, Greg, Krest, S.K., and Sparling, D.W., eds., 2003a, 

Amphibian decline—An integrated analysis of multiple 

stressor effects: Pensacola, FL, Society of Environmental 

Toxicology and Chemistry, 368 p.

Linder, Greg, Krest, S.K., Sparling, D.W., and Little, E.E., 

eds., 2003b, Multiple stressor effects in relation to declining 

amphibian populations: West Conshohocken, PA, American 

Society for Testing and Materials International, Selected 

Technical Paper 1443, 282 p. [Also available at http://www.

astm.org/DIGITAL_LIBRARY/STP/SOURCE_PAGES/

STP1443.htm.]

Longcore, J.R., Longcore, J.E., Pessier, A.P., and Halteman, 

W.A., 2007, Chytridiomycosis widespread in anurans of 

northeastern United States: Journal of Wildlife Management, v. 71, no. 2, p. 435–444. [Also available at http://

www.jstor.org/stable/4495202.]

Loveridge, Arthur, 1948, New Guinean reptiles and amphibians in the Museum of Comparative Zoölogy and United 

States National Museum: Bulletin of the Museum of Comparative Zoology, v. 101, no. 2, p. 305–430. [Also available 

at http://biostor.org/reference/49254.]

Lovich, J.E., Scott, N.J., Jr., Bury, R.B., Dodd, C.K., Jr., and 

McDiarmid, R.W., 2012, A history of herpetologists and 

herpetology in the U.S. Department of the Interior: Herpetological Conservation and Biology, v. 7, Monograph 2, 

p. 1–45. [Also available at http://herpconbio.org/Volume_7/

Monographs/Lovich_etal_2012.pdf.]

MacCulloch, R.D., Lathrop, Amy, Reynolds, R.P., Señaris, 

J.C., and Schneider, G.E., 2007, Herpetofauna of Mount 

Roraima, Guiana Shield region, northeastern South 

America: Herpetological Review, v. 38, no. 1, p. 24–30. 

[Also available at https://www.pwrc.usgs.gov/prodabs/

reynolds/6735_macculloch.pdf.]

MacCulloch, R.D., and Reynolds, R.P., 2012, Amphibians 

and reptiles from Paramakatoi and Kato, Guyana: Check 

List, v. 8, no. 2, p. 207–210. [Also available at http://www.

checklist.org.br/getpdf?SL004-12.]

MacCulloch, R.D., and Reynolds, R.P., 2013, Baseline inventory of amphibians and reptiles in the vicinity of Kurupukari, Guyana: Check List, v. 9, no. 6, p. 1378–1382. [Also 

available at http://www.checklist.org.br/getpdf?SL091-12.]

MacKenzie, D.I., Nichols, J.D., Lachman, G.B., Droege, 

Sam, Royle, J.A., and Langtimm, C.A., 2002, Estimating 

site occupancy when detection probabilities are less than 

one: Ecology, v. 83, no. 8, p. 2248–2255. [Also available at 

http://dx.doi.org/10.1890/0012-9658(2002)083[2248:ESOR

WD]2.0.CO;2.]

McDiarmid, R.W., and Altig, Ronald, eds., 1999, Tadpoles—

The biology of anuran larvae: Chicago, IL, University of 

Chicago Press, 458 p.

McDiarmid, R.W., Foster, M.S., Guyer, C., Gibbons, J.W., and 

Chernoff, N., eds., 2012, Reptile biodiversity—Standard 

methods for inventory and monitoring: Berkeley, CA, University of California Press, 412 p.
126 The History of Patuxent: America’s Wildlife Research Story

Muths, Erin, Jung, R.E., Bailey, L.L., Adams, M.J., Corn, P.S., 

Dodd, C.K., Jr., Fellers, G.M., Sadinski, W.J., Schwalbe, 

C.R., Walls, S.C., Fisher, R.N., Gallant, A.L., Battaglin, 

W.A., and Green, W.A., 2005, Amphibian Research and 

Monitoring Initiative (ARMI)—A successful start to a 

national program in the United States: Applied Herpetology, v. 2, no. 4, p. 355–371. [Also available at http://www.

werc.usgs.gov/fileHandler.ashx?File=/Lists/Products/

Attachments/3351/ARMI%20program.pdf.]

Perry, M.C., ed., 2007, The Washington Biologists’ Field 

Club—Its members and its history (1900–2006): Washington, D.C., Washington Biologists’ Field Club, 342 p. [Also 

available at http://www.pwrc.usgs.gov/resshow/perry/bios/

wbfc_booksm.pdf.]

Perry, M.C., Osenton, P.C., Fallon, F.W., and Fallon, J.E., 

1997, Optimal management strategies for biodiversity within a powerline right-of-way, in Williams, J.R., 

Goodrich-Mahoney, J.W., Wisniewski, J.R., and Wisniewski, Joe, eds., Sixth International Symposium on 

Environmental Concerns in Right-of-Way Management: 

New York, Elsevier Science, p. 133–139. [Also available 

at https://www.researchgate.net/publication/283296233_

Optimal_management_strategies_for_biodiversity_

within_a_powerline_right-of-way.]

Perry, M.C., Osenton, P.C., and Stoll, C.S., 2001, Biological diversity of created forested wetlands in comparison 

to reference forested wetlands in the Bay watershed, in

Therres, G.D., ed., Conservation of biological diversity—A 

key to the restoration of Chesapeake Bay ecosystem and 

beyond: Annapolis, MD, Maryland Department of Natural 

Resources, p. 261–268. [Also available at http://ecos.fws.

gov/ServCatFiles/reference/holding/45966.]

Perry, M.C., Sibrel, C.B., and Gough, G.A., 1996, Wetlands 

mitigation—Partnership between an electric power company and a federal wildlife refuge: Environmental Management, v. 20, no. 6, p. 933–939. [Also available at https://

www.researchgate.net/publication/225222349_Wetlands_

mitigation_Partnership_between_an_electric_power_

company_and_a_federal_wildlife_refuge.]

Reynolds, R.P., and Foster, M.S., 1992, Four new species 

of frogs and one new species of snake from the Chapare 

region of Bolivia, with notes on other species: Herpetological Monographs, v. 6, p. 83–104. [Also available at http://

dx.doi.org/10.2307/1466963.]

Reynolds, R.P., and MacCulloch, R.D., 2012, Preliminary 

checklist of the amphibians and reptiles of Baramita, Guyana: Check List, v. 8, no. 2, p. 211–214. [Also available at 

http://www.checklist.org.br/getpdf?SL003-12.]

Rodda, G.H., Fritts, T.H., and Reichel, J., 1991, The distributional patterns of reptiles and amphibians in the Mariana Islands: Micronesica, v. 24, no. 2, p. 195–210. [Also 

available at https://issuu.com/marc_virtual_library/docs/

the_distributionl_patterns_of_repti/1.]

Sparling, D.W., Linder, Greg, and Bishop, C.A., eds., 2000, 

Ecotoxicology of amphibians and reptiles: Pensacola, 

FL, Society of Environmental Toxicology and Chemistry, 

SETAC Technical Publications Series, 617 p.

Stickel, L.F., 1950, Populations and home range relationships 

of the box turtle, Terrapene c. carolina (Linnaeus): Ecological Monographs, v. 20, no. 4, p. 351–378. [Also available at 

http://dx.doi.org/10.2307/1943570.]

Stickel, L.F., 1978, Changes in a box turtle population during 

three decades: Copeia, v. 1978, no. 2, p. 221–225. [Also 

available at http://dx.doi.org/10.2307/1443554.]

Stickel, L.F., 1996, Obituary—William H. Stickel, 1912–1996: 

Wildlife Society Bulletin, v. 24, no. 2, p. 369–370. [Also 

available at http://www.jstor.org/stable/3783137.]

Stickel, W.H., 1942, A partially scaleless garter-snake: Copeia, 

v. 1942, no. 3, p. 181. [Also available at http://dx.doi.

org/10.2307/1438220.]

Uhler, F.M., 1944, Facts about snakes: Washington, D.C., U.S. 

Fish and Wildlife Service, Wildlife Leaflet No. 257, 10 p. 

[Also available at https://archive.org/details/factsaboutsnakes103usfi.]

Uhler, F.M., Cottam, Clarence, and Clark, T.E., 1939, Food of 

snakes of the George Washington National Forest, Virginia: 

Transactions of the North American Wildlife Conference, 

v. 4, p. 605–622.

Weir, L.A., and Mossman, M.J., 2005, North American 

Amphibian Monitoring Program (NAAMP), in Lannoo, 

Michael, ed., Amphibian declines—The conservation status 

of United States species: Berkeley, CA, University of California Press, p. 307–313.

Whiting, M.J., Dixon, J.R., Greene, B.D., Mueller, J.M., 

Thornton, O.W., Jr., Hatfield, J.S., Nichols, J.D., and Hines, 

J.E., 2008, Population dynamics of the Concho water snake 

in rivers and reservoirs: Copeia, v. 2008, no. 2, p. 438–445. 

[Also available at http://www.pwrc.usgs.gov/prodabs/hatfield/Whiting_et_al_2008.pdf.]

Wynn, A.H., Reynolds, R.P., Buden, D.W., Falanruw, Marjorie, and Lynch, Brian, 2012, The unexpected discovery of 

blind snakes (Serpentes: Typhlopidae) in Micronesia—Two 

new species of Ramphotyphlops from the Caroline Islands: 

Zootaxa, v. 3172, p. 39–54. [Also available at http://www.

mapress.com/zootaxa/2012/f/z03172p054f.pdf.]
Environmental Contaminant Research Program

Chesapeake Bay Contaminant Studies by Patuxent 

Wildlife Research Center Scientists

By Barnett A. Rattner

Chesapeake Bay is the largest estuary in the United States (165,000 square kilometers [63,700 square miles]). In the 

1600s, the bay “teemed with life,” and forests covered 95 percent of the watershed (Alliance for the Chesapeake 

Bay, 1998, unpub. fact sheet). The arrival of European settlers was accompanied by the clearing of forests and 

gradual conversion of wetlands to agriculture and urban centers, and, in the centuries that followed, the ability 

of the watershed to keep contaminants from reaching the bay and its tributaries diminished (Baldwin and others, 

2012). In addition to the loss of habitat, overharvesting of living resources, as well as agricultural, industrial, and 

urban activities, have had major effects on invertebrate, fish, and wildlife populations residing in the bay and 

its watershed.

During its 75-year history, staff of the Patuxent Research Refuge and its successor research entities (Patuxent) 

and affiliates have contributed greatly to our present-day understanding of Chesapeake Bay. Our contaminant 

biologists (today more commonly referred to as wildlife toxicologists or ecotoxicologists) have conducted 

innumerable laboratory and controlled exposure investigations (for example, egg injection studies involving 

developing embryos in incubators, young and adult wildlife in cages or pens), field monitoring, and hypothesisdriven studies. By using a combined laboratory/pen-field approach, Patuxent scientists have elucidated both 

the direct and indirect effects of environmental contaminants on wildlife. Notably, some of the first studies of 

the effects of dichlorodiphenyltrichloroethane (DDT) on wild birds and mammals were conducted in forests at 

Patuxent or surrounding areas within the bay watershed, and their place in the history of wildlife toxicology is well 

established (for example, studies by Robert Stewart, Lucille Stickel, Chandler Robbins, Clarence Cottam, and others 

as described in an historical review by Rattner [2009]). Although the geographic scope of nearly all our studies is 

broad, this chapter is an historical perspective of Patuxent research efforts that specifically examined contaminant 

exposure and resulting effects on Chesapeake Bay wildlife and their supporting habitat.

Early Years

Through interviews with retirees who worked at Aberdeen Proving Ground, the U.S. Army facility in Aberdeen, 

MD, it was learned that an unknown quantity of white phosphorus munitions is said to be buried offshore (that is, a barge 

containing munitions may have been purposefully or accidentally sunk) in the vicinity of Black Point (upper Chesapeake 

Bay near U.S. Army Aberdeen Proving Ground) between 1922 

and 1925 (John Paul and John Wrobel, U.S. Army Garrison, 

Aberdeen Proving Ground, MD, oral commun., 2012). In 

addition, large segments of open water in this region had been 

used for decades as an ordnance impact area. Undoubtedly, 

ignited white phosphorus from artillery rounds was extinguished upon entering the bay. In 1933, the so-called burial 

site was disturbed by a hurricane. Resuspended white phosphorus may have been responsible for the large waterfowl kill 

that followed (ducks were said to have “turned pink and died”) 

(see the U.S. Environmental Protection Agency Superfund 

Record of Decision [U.S. Environmental Protection Agency, 

1991]). In 1939, Secretary of the Interior Harold Ickes designated parts of the site as a Migratory Waterfowl Closed Area 

for waterfowl hunting. These events and subsequent waterfowl die-offs may have been the impetus for a study of white 

phosphorus toxicity in mallards (Anas platyrhynchos) and 

American black ducks (hereafter black ducks) (Anas rubripes) 

(Coburn and others, 1950). In one of the first studies with 

captive waterfowl at Patuxent, survival of, and hematologic 

and histopathological responses to, acute and chronic exposure 

regimens were examined. Remarkably, tissue phosphorus concentrations in control and treated birds were determined and 

compared by using inferential statistical methods. Don Coburn 

and coworkers (1950) evaluated phosphorus concentrations 

in redhead ducks (Aythya americana) collected from northern Chesapeake Bay that were suspected to have died from 

phosphorus poisoning and concluded “it appears probable” the 
128 The History of Patuxent: America’s Wildlife Research Story

birds had been killed by ingestion of elemental phosphorus. 

This issue reemerged and was scientifically revisited following 

frequent waterfowl die-offs at a military firing range on the 

Eagle River Flats, AK, from 1980 to the mid-1990s (reviewed 

by Sparling, 2003). The U.S. Army has since banned the firing 

of white phosphorus rounds over the wetlands at Eagle River 

Flats (U.S. Department of Defense, 2007).

1960s

Following the publication of “Silent Spring” (Carson, 

1962), a National Pesticide Monitoring Program was initiated 

in response to public concern (Johnson and others, 1967). 

The Bureau of Sport Fisheries and Wildlife of the U.S. Fish 

and Wildlife Service (USFWS), including staff at Patuxent, 

collected starlings (Sturnus vulgaris) (initially at 44 locations, 

then at 110 locations), obtained hunter-collected mallard and 

black duck wings from nearly every state in the continental 

United States (organized into the four North American Flyways), and was sent dead golden eagles (Aquila chrysaetos) 

and bald eagles (Haliaeetus leucocephalus) from many locations across the country (Johnson and others, 1967). Samples 

initially were analyzed for organochlorine pesticides. Many 

Patuxent scientists contributed to the nationwide monitoring 

of starlings and duck wings in the decades that followed. The 

suite of analytes was expanded to include polychlorinated 

biphenyls (PCBs) and metals, and results were chronicled 

in special USFWS reports and scientific journal publications (Schmitt and Bunck, 1995). Because these monitoring 

schemes focused on nationwide trends over time, little information can be derived with respect to comparisons of contaminant concentrations between states or within a particular 

estuary, such as Chesapeake Bay.

Examination of data obtained from 69 moribund or dead 

bald eagles collected in 25 states from 1966 to 1968 included 

one specimen from the Chesapeake Bay region. That eagle 

contained a dieldrin concentration of 4.3 micrograms per gram 

(μg/g) brain tissue on a wet weight (ww) basis, which may 

have contributed to its death (Mulhern and others, 1970), and 

another suspected dieldrin poisoning (11 μg/g ww) was documented in 1970 (Belisle and others, 1972). Regionally focused 

studies also were conducted during this period. For example, a 

survey of organochlorine pesticide residues in black duck eggs 

was conducted in 1964 (Reichel and Addy, 1968). The dataset 

indicated that eggs from the Chesapeake Bay region contained 

lower concentrations of dichlorodiphenyltrichloroethane 

(DDT), dichlorodiphenyldichloroethylene (DDE), dichlorodiphenyldichloroethane (DDD), and dieldrin than samples 

from New Jersey, New York, Massachusetts, and other North 

Atlantic States.

Perhaps one of the most classic avian contaminant field 

studies of this era entailed the exchange of osprey (Pandion 

haliaetus) eggs from nests on the lower Potomac River, 

MD, with eggs from Old Lyme, Niantic, Trumbull Airport, 

and Mason’s Island in Connecticut by Stan Wiemeyer, Paul 

Spitzer, and others (Wiemeyer and others, 1975). The results 

of this highly cited study indicate that the most probable cause 

of poor reproduction in Connecticut ospreys was DDE, dieldrin, and PCB contamination, of both fish consumed and eggs 

laid by ospreys.

Young ospreys in nest on the James River, VA, 2012. Photo by Rebecca S. Lazarus, U.S. Geological Suvey.
Environmental Contaminant Research Program

Chesapeake Bay Contaminant Studies by Patuxent Wildlife Research Center Scientists 129

1970s

During the 1970s, Patuxent scientists devoted much effort 

to generating basic toxicological data on pesticides, industrial 

compounds, and metals through controlled-exposure studies 

with penned or caged birds (for example, Northern bobwhite 

[Colinus virginianus], Japanese quail [Coturnix japonica], 

mourning doves [Zenaida macroura], waterfowl, raptors, and 

black-crowned night-herons [Nycticorax nycticorax]. In addition, many regional or national contaminant-monitoring efforts 

included Chesapeake wildlife and, in some instances, research 

studies focused directly on the bay.

A study of ospreys on the Potomac River in 1970 and 

1971 revealed low reproductive success, and indicated that the 

effects of pesticides and other contaminants could be investigated as a possible cause (Wiemeyer, 1971, 1977). Osprey 

eggs collected from 1970 to 1978 contained about 3 μg/g DDE 

ww; other organochlorine pesticides were present at much 

lower concentrations, yet PCBs were present at concentrations as high as 20 μg/g ww (Wiemeyer and others, 1988). In 

some instances, eggshell thinning approached levels (greater 

than 15 percent) that are associated with breakage and reduced 

reproductive success. Using aerial surveys by Patuxent 

scientists Chuck Henny, Vern Stotts, and others, Henny and 

others (1974) estimated the Chesapeake Bay osprey population to be about 1,450 nesting pairs in 1973; however, only 

7 of these nesting pairs were observed in the northwestern 

part of the bay, and only 2 nesting pairs were observed on 

the James River and nearby tributaries. These results triggered several osprey ecotoxicological investigations in the 

subsequent decades.

During this era, Chesapeake Bay bald eagle eggs that 

failed to hatch contained greater concentrations of organochlorine pesticides than those from 13 other states (Wiemeyer 

and others, 1984), and eggshells were significantly thinner 

(-11 percent in Maryland and -18 percent in Virginia) than 

museum samples collected before the introduction of DDT 

(before 1946). In a continuation of this sampling effort, 

DDE concentrations in eagle eggs had declined by 1980–84, 

although shell thickness still averaged 13 to 14 percent less 

than pre-1946 values (Wiemeyer and others, 1993).

At about the same time (1972–73), eggs of barn owls 

(Tyto alba) were collected from offshore duck blinds on the 

lower Potomac River (Klaas and others, 1978). Eggshell thickness was determined to be inversely related to DDE, DDD, 

and dieldrin concentrations, and reproduction (1.7 young 

per clutch) was slightly less than that necessary to maintain 

population stability. In a long-term study of red-shouldered 

hawk (Buteo lineatus) populations in the Patuxent River 

Valley (1943–71), Henny and coworkers (Henny and others, 

1973) suggested that concentrations of DDT, its metabolites, 

and dieldrin may have caused as much as a 9-percent decrease 

in eggshell thickness in samples collected in 1971, although 

it was unlikely that such exposure was having detrimental 

effects on hawk populations in this region.

As part of an eastern United States sampling effort in 

1972 and 1973, concentrations of DDE and PCBs in eggs 

collected from great blue herons (Ardea herodias) and cattle 

egrets (Bubulcus ibis) nesting in the Potomac River were 

determined to be low to moderate compared to those in eggs 

collected from nests in other regions (Ohlendorf and others, 

1979). In a highly cited publication, Patuxent scientist Harry 

Banded young ospreys on nest in Chesapeake Bay, 2012. Photo by Rebecca S. Lazarus, U.S. Geological Survey.
130 The History of Patuxent: America’s Wildlife Research Story

Ohlendorf and others (1978) described contaminants in blackcrowned night herons (Nycticorax nycticorax) and determined 

that eggs in Chincoteague, VA, in the Chesapeake Bay region 

(but not the bay proper) contained low to moderate concentrations of chlorinated hydrocarbons and metals; no evidence of 

substantial shell thinning was observed. This colony was used 

as a reference site for many studies in subsequent decades. 

In 1978, black duck eggs were collected along the Atlantic 

Flyway, and concentrations of DDE, PCBs, and mercury 

were determined to be the lowest in the Chesapeake Bay 

region (Pennsylvania, Maryland, Virginia) compared to more 

northerly locations extending into Nova Scotia (Haseltine and 

others, 1980).

Pesticide residues in carcass and brain, and metals in 

liver and kidney, were quantified in a subset of 15 ospreys 

found dead in the Chesapeake Bay region (1964–73; Wiemeyer and others, 1980). Large concentrations of organochlorine pesticides and PCBs were detected in a few individuals 

(for example, greater than 40 μg/g ww in brain or carcass for 

DDE and PCBs), although the extreme values for mercury and 

lead in these Chesapeake Bay region samples were generally 

lower than values for samples from New York, New Jersey, 

Ohio, and Florida. Other geographically broad-scale efforts 

to monitor carcasses and tissues that included samples from 

the Chesapeake Bay drainage area used American woodcock 

(Scolopax minor) (Clark and McLane, 1974), mourning doves 

(Kreitzer, 1974), and herons (Ohlendorf and others, 1981). 

Concentrations of chlorinated hydrocarbons and mercury in 

these samples were generally moderate compared to concentrations in samples from other regions in the United States. 

One possible exception was dieldrin, which was implicated 

in several poisonings of bald eagles in the Chesapeake Bay 

region in the 1960s and 1970s (Cromartie and others, 1975; 

Prouty and others, 1977). Furthermore, of 27 herons found 

dead in the Chesapeake Bay region from 1966 to 1978, 3 great 

blue herons and 2 cattle egrets contained dieldrin residues 

that probably contributed to their deaths (Ohlendorf and 

others, 1981).

To investigate the potential role of contaminants in 

declining populations of canvasbacks (Aythya valisineria), 

blood samples were collected from birds trapped at two Chesapeake Bay locations (Westmoreland State Park in Virginia and 

Cove Point in Maryland) by Patuxent scientists Mike Dieter 

and Matt Perry from 1972 to 1974 (Dieter and others, 1976). 

Abnormal enzyme activity was detected in about 20 percent of 

the samples; plasma aspartate aminotransferase activity was 

positively correlated with PCB and DDE concentrations in 

blood, and whole blood delta-aminolevulinic acid dehydratase 

(ALAD) activity was inversely related to lead concentrations 

in blood. This was the first published report describing the use 

of ALAD inhibition as a biomarker of lead exposure in wildlife, and its use in lead studies and Natural Resource Damage 

Assessments continues to the present day (2016). In a related 

study, canvasback carcass and tissue samples collected in 

1973, 1975, and 1976 were analyzed for chlorinated hydrocarbons and several metals (cadmium, chromium, copper, lead, 

mercury, and zinc); for most individuals, concentrations were 

less than levels known to cause adverse effects (White and 

others, 1979).

One of many necropsy case reports described by Patuxent 

scientist Lou Locke involved a moribund tundra swan (Cygnus 

columbianus) collected on the bank of Seneca Creek in Essex, 

MD (Locke and Young, 1973); this case report is particularly 

important because it may have been the first paper attributing 

lead poisoning in a swan to ingestion of fishing tackle. Patuxent veterinarian Jim Carpenter contributed to another case 

report that described an immature bald eagle recovered from 

western Maryland that died during treatment and rehabilitation 

attempts (Jacobson and others, 1977). Lead concentrations in 

tissues were elevated (liver, 22.9 μg/g; kidney, 12.3 μg/g), but 

most remarkable were the radiograph and necropsy of the gizzard, which contained 20 lead pellets.

Pair of canvasbacks used in contaminant study, Chesapeake Bay, 1976. Photo 

by Matthew C. Perry, U.S. Fish and Wildlife Service.

Oiled canvasback in Chesapeake Bay, 1978. Photo by Matthew C. Perry, 

U.S. Fish and Wildlife Service.
Environmental Contaminant Research Program

Chesapeake Bay Contaminant Studies by Patuxent Wildlife Research Center Scientists 131

Tidal salt marsh in Chesapeake Bay, 1978. Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.

During this period, Patuxent contaminant studies in mammals were limited. Patuxent scientist Don Clark and coworkers 

(Clark and Krynitsky, 1978; Clark and Lamont, 1976; Clark 

and Prouty, 1976) documented DDE and PCB concentrations 

in several species of bats (big brown bat [Eptesicus fuscus], 

little brown bat [Myotis lucifugus], eastern pipistrelle [Pipistrellus subflavus]) captured in Maryland and West Virginia. 

The many purposes of these studies included comparing placental transfer and sensitivity of fetuses to these compounds. 

In a review published decades later (Clark and Shore, 2001), 

concentrations of chlorinated contaminants in these bats from 

the Chesapeake Bay region were moderate to low compared to 

those in bats from other locations in the United States. Notably, whole-body concentrations of lead in big brown and little 

brown bats exceeded concentrations determined in meadow 

voles (Microtus pennsylvanicus), white-footed mice (Peromyscus leucopus), and short-tailed shrews (Blarina brevicauda) 

in the Chesapeake Bay region, but were comparable to levels 

measured in bats collected at mining sites (Clark, 1979).

Just after the close of the decade, Harry Ohlendorf (1981) 

summarized organochlorine contaminant data for birds collected in Chesapeake Bay at the Forty-Sixth North American 

Wildlife and Natural Resources Conference in Washington, 

D.C., in 1981. Ohlendorf pointed out that although organochlorine compounds were still present in eggs and tissues, the 

production of the two compounds of greatest concern, DDT 

and dieldrin, had been banned for use in the United States, and 

the manufacture and use of other organochlorine pesticides and 

industrial compounds had declined (for example, production 

of Kepone in Hopewell, VA; this compound had contaminated 

much of the James River [Huggett and Bender, 1980], and was 

suspended, and sales of PCBs had been restricted). In closing, Ohlendorf states “...it appears that the impact of these 

chemicals in the future should be much less than in the past 

35 years. In the Chesapeake Bay attention should be focused 

on fish-eating birds, primarily bald eagles and ospreys, but it 

is unlikely that organochlorines will present a serious threat 

to these species, or others of the Chesapeake Bay region” 

(Ohlendorf, 1981).

1980s

Unlike the decline in DDE concentrations observed in 

bald eagle eggs in the Chesapeake Bay area, a similar trend for 

DDE in osprey eggs collected at the Glenn L. Martin National 

Wildlife Refuge, Chesapeake Bay, in 1986 was not statistically 

supported, and the concentrations present were reported to be 

large enough to cause a 10-percent eggshell thinning (Audet 

and others, 1992). At that particular location, PCB concentrations appeared to have declined, and other DDT metabolites 

and dieldrin were not detected. Results of additional studies 

of osprey carcasses from Chesapeake Bay (1975–82) revealed 

that concentrations of some organochlorine compounds had 

declined substantially (Wiemeyer and others, 1987). Interestingly, the mercury concentration of 21 μg/g ww in the liver of 
132 The History of Patuxent: America’s Wildlife Research Story

one of the dead ospreys might have contributed to the death 

of this bird, which was killed when it was struck by a motor 

vehicle (Wiemeyer and others, 1987).

Departing from the long-standing focus of Patuxent 

biologists on wildlife, Jim Fleming and coworkers (Fleming and others, 1988) led a series of studies of submerged 

aquatic vegetation (SAV). Water-quality problems and storms 

in the bay had long been identified as the most likely causes 

of dramatic declines in the abundance of SAV, and its loss 

adversely affected other biota throughout the bay. The toxicity 

of the widely used herbicide atrazine was tested using sago 

pondweed (Potamogeton pectinatus) grown in sterile cultures 

(anexic conditions) and in buckets (nonaxenic conditions). 

At concentrations of 1,000 micrograms per liter, atrazine 

impaired growth of plants in both axenic and nonaxenic conditions. This bioassay system showed considerable promise for 

effluent screening and testing in Chesapeake Bay.

In 1987 and 1988, Patuxent scientist Keith Miles collected samples of sediment, composites of various invertebrates, and clams (Macoma spp.) in Baltimore Harbor, MD, 

where large numbers of waterfowl had been observed to 

feed and rest (Miles and Tome, 1997). These samples were 

analyzed for 20 metals and metalloids, and concentrations of 

many elements were greater in invertebrates than in sediment. 

At some locations, concentrations of aluminum, boron, chromium, mercury, lead, and selenium exceeded toxic thresholds, 

and it was suggested that individual birds using some of the 

study areas might be adversely affected, although probably 

not at the population level. In a companion waterfowl study, 

concentrations of metals and metalloids were measured in 

livers of dabbling and diving ducks collected from Baltimore 

Harbor by Patuxent scientist Mike Tome. Lead concentrations 

exceeded the 2-μg/g ww threshold for subclinical poisoning in 

some mallards, black ducks, and scaup (Aythya spp.), but mercury, cadmium, and selenium levels were generally well below 

toxicity thresholds (U.S. Geological Survey, 2014; Rattner and 

McGowan, 2007).

Contamination in Baltimore Harbor, MD, 1973. Photo by Matthew C. Perry, U.S. 

Fish and Wildlife Service.

Toward the end of the decade, Patuxent scientists Ohlendorf and Fleming (1988) undertook a comparison of Chesapeake Bay and San Francisco Bay waterbird contaminant data 

collected. Based on field and laboratory studies, the authors 

concluded that the concentrations of some trace elements 

and organochlorine compounds in avian tissues and their 

food items could evoke adverse effects. In Chesapeake Bay, 

elevated concentrations of cadmium and lead in seaducks, 

lead in dabbling waterfowl, and DDE in ospreys and bald 

eagles were of concern, whereas major issues in San Francisco 

Bay included selenium, cadmium, and mercury in waterfowl 

and PCBs and DDE in shorebirds and herons. Ohlendorf and 

Fleming (1988) outlined a research- and information-needs 

strategy, but ultimately their plan was only partially pursued as 

a result of funding limitations and shifts in research priorities.

1990s

Patuxent staff members became increasingly involved 

with the Chesapeake Bay Program, a consortium of Federal, 

State, and nonprofit agencies and organizations working 

toward bay restoration. With the passage of the 1987 Chesapeake Bay Agreement, we began to serve on committees and 

collaborate with other scientists to develop guidelines for the 

protection of habitat, water quality, and living resources in 

Chesapeake Bay. At about this time, many of our researchers developed long-lasting collaborations with contaminant 

biologists (operational staff) at the Chesapeake Bay field 

office of the USFWS that continue to this day (2016). Gary H. 

Heinz and Stan Wiemeyer prepared a chapter titled “Effects 

of Contaminants on Birds” (Heinz and Wiemeyer, 1991) in 

the frequently cited compendium “Habitat Requirements 

for Chesapeake Bay Living Resources: A Report from the 

Chesapeake Bay Living Resources Task Force” (Funderburk 

and others, 1991). They describe the history of contaminant 

effects on birds of Chesapeake Bay and point out that the 

banning of the most harmful organochlorine pesticides and the 

replacement of lead shot with steel shot has reduced poisoning 

and reproductive problems. Nevertheless, they suggest that 

contaminants such as cadmium, petroleum (oil), and industrial 

chemicals could adversely affect avian species.

A small nesting colony of black-crowned night herons 

became established in the Baltimore Harbor area in 1979 

and had grown to 300 nests by 1990, constituting the largest 

colony of this species in Maryland. Remarkably, the foraging habits of this colony were concentrated in this highly 

industrialized area (Erwin and others, 1991), one of three U.S. 

Environmental Protection Agency-designated Chesapeake Bay 

Regions of Concern. The colony was popularized in an article 

by Patuxent scientist Mike Erwin titled “Industrial Strength 

Herons,” which appeared in “Maryland Magazine” (Erwin 

and others, 1990). In 1991, Mark Melancon began a study 

examining contaminant exposure and hepatic cytochrome 

P450 induction (a biochemical biomarker of polyhalogenated 

hydrocarbon exposure) in pipping embryos and nestlings from 
Environmental Contaminant Research Program

Chesapeake Bay Contaminant Studies by Patuxent Wildlife Research Center Scientists 133

the Baltimore Harbor heron colony and at a colony in Rock 

Creek Park in Washington, D.C. (Rattner and others, 1997). 

Cytochrome P450-associated monooxygenase enzymes were 

induced more than fivefold in pipping embryos from Baltimore Harbor and to a smaller degree in those from Rock Creek 

Park, and concentrations of organochlorine contaminants in 

pipping embryos and nestlings were markedly elevated compared to those collected from the Chincoteague Bay reference 

site. The concentration of some PCB congeners (numbers 77 

and 126) actually exceeded values observed in this species in 

the Great Lakes and appear to have been partly responsible for 

cytochrome P450 induction (Rattner and others, 1997).

These results were the impetus for testing the hypothesis that PCBs might be leading to the declining size of the 

Baltimore Harbor heron colony. In a follow-up study conducted in 1998, USFWS Chesapeake Bay field office biologist 

Pete McGowan and I determined that the heron colony had 

moved about 2 kilometers (1.2 miles) south to Fort Carroll, 

a mid-19th-century military structure built by Robert E. Lee 

before the Civil War. In a large-scale study, concentrations 

of 12 arylhydrocarbon receptor-active PCB congeners and 

dioxin-related toxic equivalents were more than 35 times 

greater in sampled eggs from Baltimore Harbor than in those 

from the reference site in southern Chesapeake Bay (Holland 

Island). Seventy-four percent of the nests produced at least one 

chick, and productivity (2.05 young per nest) was adequate to 

maintain a stable population (Rattner and others, 2001). No 

significant relation was found between hatching, fledging, or 

overall reproductive success and concentrations of PCBs and 

toxic equivalents. The authors concluded that contaminants 

were not having a dramatic effect on reproduction in the Baltimore Harbor heronry. In the years that followed, the numbers 

of black-crowned night herons at Fort Carroll continued to 

decrease to a mere 17 pairs in 2008 (D.F. Brinker, Maryland 

Department of Natural Resources, oral commun., 2008), and 

this now-mixed waterbird colony was dominated by doublecrested cormorants (Phalacrocorax auritus), herring gulls 

(Larus argentatus), and cattle egrets.

Led by colleagues of the USFWS Chesapeake Bay 

field office, Mark Melancon and Dave Hoffman of Patuxent 

assisted with a study of potential contaminant effects in great 

blue herons nesting at Mason Neck National Wildlife Refuge 

on the banks of the Potomac River in Lorton, VA, in 1997 

(Johnson and others, 2001). Eggs were collected and artificially incubated, and biochemical (cytochrome P450 and measures of oxidative stress) and eggshell-thickness measurements 

did not differ from those for the Coaches Island reference site. 

Results indicated that great blue herons at Mason Neck, the 

largest great blue heron colony in Virginia, were probably not 

being adversely affected by polyhalogenated contaminants.

As part of a study examining potential endocrine disruptive effects of PCBs, Patuxent scientist John French 

reported that common tern (Sterna hirundo) eggs from South 

Sand Point (off Barren Island in Maryland and Virginia) 

in 1994 contained relatively low levels of Aroclor 1260 

(0.44–1.50 μg/g ww) (U.S. Geological Survey, 2014; Rattner 

and McGowan, 2007). As part of this effort, eggs also were 

collected from Bodkin Island, MD, in 1997 and contained less 

than 10 micrograms total PCB per gram lipid; Bodkin Island 

served as a comparative reference site for the more contaminated samples from Ram Island in Buzzards Bay, MA (French 

and others, 2001). There was no evidence that the concentrations of steroid hormones that were maternally deposited in 

eggs were affected by contaminant exposure.

Tree swallow (Tachycineta bicolor) eggs and nestlings 

were collected from the Patuxent River, a tributary to the middle Chesapeake Bay, to serve as a reference for PCB-contaminated sites in Indiana, New York, and Pennsylvania (Yorks, 

1999). As expected, total PCB concentrations in samples from 

the Patuxent reference site (eggs, 0.69 μg/g ww; nestling carcass, 0.29 μg/g ww) were much lower than those in samples 

from the PCB-contaminated sites (eggs, 0.94–4.6 μg/g ww; 

nestling carcass, 0.17–18.5 μg/g ww).

Following an avian cholera outbreak in 1994, 41 longtailed duck (Clangula hyemalis) carcasses were collected 

throughout Chesapeake Bay (Mashima and others, 1998). 

Liver and kidney cadmium concentrations were greater in 

birds that succumbed to cholera than in apparently healthy 

birds collected during 1985–87. The authors suggested that 

cadmium may have contributed to cholera susceptibility in 

these ducks, and concentrations of lead, mercury, and selenium 

in tissues were probably too low to evoke immunotoxicity. 

The authors also indicated that weight loss owing to cholera 

could have concentrated metals in tissues.

As part of a series of studies examining tissue uptake of 

metals from ingested soil and sediment, Nelson Beyer, Dan 

Day, and other Patuxent colleagues collected mute swans 

(Cygnus olor) from several locations in Chesapeake Bay (for 

example, Bloodsworth Island, Horseheads Wetland Center, 

and Eastern Neck and Blackwater National Wildlife Refuges) 

(Beyer and others, 1998). Concentrations of metals in sediment were low, and concentrations in liver were considered 

to be at background levels for this species. Copper concentrations were remarkably high (as much as 1,200 milligrams 

per kilogram dry weight [dw]); apparently swans, in the 

absence of environmental contamination, can accumulate large 

quantities of copper in the liver, far more than other species 

of waterfowl. Although this study revealed little about the 

hazards posed by sediment to mute swans throughout the bay, 

it demonstrated the importance of sediment ingestion for the 

accumulation of lead in mute swans. Additional studies near 

Aberdeen Proving Ground indicated that hepatic lead, cadmium, copper, and selenium concentrations did not represent a 

toxic threat to the swans (Beyer and Day, 2004).

Some heavy metals can be incorporated into feathers 

at the time they are grown, and the sampling of feathers has 

gained some acceptance as a minimally invasive sublethal 

contaminant monitoring technique. My graduate student assistant, Nancy Golden, collected feathers from black-crowned 

night heron nestlings and determined lead concentrations in 

herons from Baltimore Harbor to average 0.32 μg/g dw, which 

was greater than those in feathers collected from Chincoteague 
134 The History of Patuxent: America’s Wildlife Research Story

Osprey on nest in Baltimore Harbor, MD, 2011. Photo by Rebecca S. Lazarus, U.S. Geological Survey.

Bay and Holland Island (less than or equal to 0.13 μg/g dw) 

(Golden and others, 2003b). In a related study of lead-dosed 

heron nestlings, red blood cell ALAD activity was inversely 

related to lead concentrations in feathers (Golden and others, 

2003a); thus, lead concentrations in feathers of some heron 

nestlings from Baltimore Harbor might be great enough to 

cause enzyme inhibition and impaired heme (porphyrin ring 

component of hemoglobin) synthesis.

Patuxent staff member Mark Melancon collaborated for 

several years with a team of scientists investigating contaminant exposure, pathological lesions, and cytochrome P450 

induction in brown bullheads (Ameiurus nebulosus) collected 

from highly contaminated locations in the Chesapeake Bay 

area, including the Anacostia River near Washington, D.C., 

and Back River and Furnace Creek near Baltimore (Pinkney 

and others, 2001, 2004). These studies documented tumor 

prevalence; concentrations of DDT, PCBs, and various polynuclear aromatic hydrocarbons (PAHs); and cytochrome P450 

induction. In some instances, tumor prevalence was associated 

with biliary PAH concentrations. Some of the skin tumors 

were rather grotesque and received considerable attention in 

the media.

2000s

With recovery and expansion of the Chesapeake osprey 

population in the 1990s, birds began nesting in some of the 

most contaminated sites in the bay, including Baltimore 

Harbor, and the Anacostia and Elizabeth Rivers. In 2000 and 

2001, a large-scale study was conducted in which osprey 

eggs were collected from nests in these Chesapeake Bay 

Regions of Concern and nearby tributaries (Rattner and others, 2004). Concentrations of DDE, dieldrin, and chlordane 

in eggs collected from the middle Potomac River in 2000 

were less than half those observed in 1970s, and there were 

no effects on reproductive success when compared to the 

reference sites (South, West, and Rhode Rivers). However, 

shell thickness of eggs from the Anacostia River and middle 

Potomac River averaged 8.7 percent less than in the pre-DDT 

era, and more than half of these sampled eggs contained DDE 

at concentrations within the 95-percent confidence interval 

(1.2–3.0 μg/g ww) associated with 10-percent eggshell thinning. Compared to total PCB values reported in eggs collected 

in the 1970s and 1980s (Wiemeyer and others, 1988), concentrations in osprey eggs in the 2000 and 2001 samples had not 

declined. Notably, total PCBs in the reference area averaged 

more than 4 μg/g ww, which alerted fisheries biologists to a 

potential hazard, eventually leading to a human-health fish 

consumption advisory for some species in the South River 

(Joseph Beaman, Maryland Department of the Environment, oral commun., 2002). Concentrations of toxicologically potent coplanar and semicoplanar PCB congeners were 

similar among study sites, and dioxin-like toxic equivalents 

were not unlike values reported for the Delaware Bay and the 

Great Lakes.

Several groups of emerging contaminants also were 

quantified in these osprey egg samples. Perhaps the most 

interesting group was the polybrominated diphenyl ethers 
Environmental Contaminant Research Program

Chesapeake Bay Contaminant Studies by Patuxent Wildlife Research Center Scientists 135

(PBDEs), which are flame retardants; concentrations 

approached 1 μg/g ww, which were some of the greatest 

values reported in bird eggs at that time. Follow-up PBDE egg 

injection studies indicated that pipping and hatching success 

might be adversely affected at 1.8 μg/g ww (McKernan and 

others, 2009). Perfluorinated surfactants also were detected 

in osprey eggs, although concentrations were well below 

adverse-effect levels. Alkylphenol and ethoxylate surfactants 

occasionally were detected in low nanogram-per-gram wet 

weight quantities, although effects of this putative endocrine 

disruptor in birds have yet (2016) to be definitively verified. 

Blood and feather samples also were collected from 40- to 

45-day old osprey nestlings, and results of analyses indicated 

that concentrations of several heavy metals (cadmium, lead, 

mercury) were well below toxicity thresholds (Rattner and 

others, 2008).

A reevaluation of contaminant exposure, biomarker 

responses, and potential reproductive effects in ospreys nesting in several tributaries and in Regions of Concern was initiated in 2011. In this large-scale collaborative study, research 

trainee Rebecca Lazarus and I are examining food-web transfer of legacy-halogenated contaminants, pharmaceuticals, and 

personal care products in water, fish, and ospreys (Lazarus and 

others, 2010). Results for legacy contaminants in osprey eggs 

revealed that concentrations of DDE are below thresholds 

associated with eggshell thinning and total PBDE concentrations have declined by 40 percent in the past decade, although 

concentrations of total PCBs in eggs from Baltimore Harbor 

and the Elizabeth River have remained unchanged (Lazarus 

and others, 2015). Of 23 pharmaceuticals measured in samples 

from the bay, 18 analytes were detected in water and 8 were 

detected in plasma from fish; only 1 of the 23 compounds (the 

antihypertensive diltiazem) was detected in nestling osprey 

plasma, but at concentrations well below the human therapeutic plasma concentration (Lazarus and others, 2014). Although 

there was some evidence of genetic damage in osprey nestlings from the most industrialized regions of the bay, overall 

findings document the continued recovery of the Chesapeake 

Bay osprey population (Lazarus and others, 2015).

Over the years, there have been many oil spills in Chesapeake Bay (about 500 incidents annually); fortunately, most 

have been small events. In 2000, a pipeline rupture released 

about 126,000 gallons of no. 2 and no. 6 fuel oil at the 

Potomac Electric Power Company Chalk Point Facility near 

Aquasco, MD. The spill spread to Swanson Creek, a tributary 

to the Patuxent River, and killed about 55 birds (principally 

waterfowl, ospreys, herons, gulls, and terns), and 109 oiled 

birds were collected for rehabilitation (Cardano, 2001; McGee 

and others, 2001). This event occurred in April and was coincident with nesting of many species. Patuxent biometrician 

Jeff Hatfield provided statistical assistance to Daniel Murphy 

and Craig Koppie of the USFWS Chesapeake Bay field office 

in evaluating reproductive success of great blue herons and 

osprey. Fortunately, nest success of herons and ospreys did 

not seem to be adversely affected by the spill (Cardano, 2001; 

McGee and others, 2001).

Barnett Rattner, U.S. Geological Survey (left), and Pete McGowan, U.S. Fish and Wildlife Service, approaching an osprey nest 

by boat in Chesapeake Bay, 2013. Photo by Reese F. Lukei, Jr., Center for Conservation Biology, College of William and Mary, 

Williamsburg, VA.
136 The History of Patuxent: America’s Wildlife Research Story

In 2001, reports of dead and dying waterbirds at the 

Poplar Island Complex, Kent Island, and Grasonville, MD, 

coincided with several harmful algal blooms (HABs). Most 

prominent was the mortality event at the Poplar Island 

Complex involving about 100 great blue herons. Results of 

necropsies performed by Patuxent veterinarian Glenn Olsen 

were consistent with steatitis (inflammation of adipose tissue), 

and microcystin toxins from cyanobacteria (Anabaena spp.) 

were detected in water samples and in tissues of dead herons. 

These HABs and the bird die-offs recurred in 2004 and 2005, 

and several hypotheses were developed (but remain untested) 

to examine the role of HABs and diet in steatitis and death of 

herons (Rattner and others, 2006).

As part of an interspecific study examining the comparative sensitivity of birds to PBDE, common tern eggs were 

collected from Poplar Island, MD, in 2010 (Rattner and others, 2013). Six eggs were chemically analyzed, and all were 

determined to contain low levels of organochlorine pesticides 

(less than 0.08 μg/g ww), total PCBs (less than 0.45 μg/g ww), 

and total PBDEs (less than 0.05 μg/g ww), indicating that eggs 

from this mid-Chesapeake Bay location could be used to study 

the commercial PBDE DE-71 formulation for embryotoxicity.

In their continued study of bullheads from many Chesapeake Bay tributaries, investigators examined tumor prevalence and biomarkers of genotoxicity (Pinkney and others, 

2011). Natalie Karouna-Renier identified DNA adducts in liver 

tissue of bullheads collected from the South and Anacostia 

Rivers, although this endpoint did not seem to be associated 

with liver- or skin-tumor prevalence.

Rattner and McGowan (2007) reviewed the potential hazards of contemporary environmental contaminants to avifauna 

in the Chesapeake Bay estuary by using the Contaminants 

Exposure and Effects—Terrestrial Vertebrates database (U.S. 

Geological Survey, 2014). They identified several groups of 

contaminants (for example, dioxins, dibenzofurans, rodenticides, pharmaceuticals, personal care products) that have not 

been systematically examined and highlighted the need for 

toxicological evaluation of birds found dead, and perhaps an 

avian ecotoxicological monitoring program.

Conclusions

Patuxent scientists have studied environmental contaminants and contamination processes in Chesapeake Bay 

for decades. Our efforts have been intermittent, reflecting 

ever-changing research priorities, perceived needs of naturalresource managers, and fluctuating budgets. During the 

organochlorine pesticide era, Chesapeake Bay served as a 

convenient outdoor laboratory to monitor exposure and test 

hypotheses. In fact, this estuary provided remarkable evidence of “a great natural experiment,” a wonderful phrase 

first coined by Patuxent contaminant biologist Bill Stickel and 

passed on to me by my colleague Gary H. Heinz. After the use 

of certain organochlorine pesticides was restricted, residues 

in tissues of wildlife and in their foods declined, toxic effects 

were abated, and, in some instances, wildlife populations (for 

example, osprey, bald eagle, peregrine falcon [Falco peregrinus]) recovered. With each successive decade, new chemicals 

and stressor interactions emerge that we must consider and 

evaluate. In the last several decades, Chesapeake Bay has 

been a source of plants and animals that can be used to study 

contaminant uptake, metabolism, clearance, and toxicity in our 

laboratories and animal holding facilities. We have contributed 

to the recovery of parts of the Chesapeake Bay ecosystem, 

but have come to the realization that it will never return to the 

condition that existed before the arrival of European settlers to 

the New World.

Acknowledgments

I thank Patuxent Wildlife Research Center scientists Drs. 

Gary H. Heinz and Harry M. Ohlendorf for providing editorial 

and technical comments on a draft of this manuscript.

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B.K., and McKernan, M.A., 2006, Harmful algal blooms 

and bird die-offs in Chesapeake Bay—A potential link?: 

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Organochlorine pesticides, polychlorinated biphenyls, and 

mercury in osprey eggs—1970–79—and their relationships 

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further interpretations of relationships to productivity and 

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C.R., Gramlich, F.J., Fraser, J.D., and Byrd, M.A., 1984, 

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BF01056332.]

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eastern United States ospreys, 1964–1973: Estuaries, v. 3, 

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the eastern United States, 1975–1982: Journal of Wildlife 

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and Cromartie, Eugene, 1975, Effects of environmental 

pollutants on Connecticut and Maryland ospreys: Journal of 

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net/10713/1326.]
Endangered Species Research Program

Overview of the Endangered Species Program

Glen Smart

In the late 1950s and early 1960s, we became increasingly aware, as a Nation, of declining populations of birds and 

mammals. Rates of extinction appeared to be skyrocketing 

and the situation was becoming critical. The country needed to 

take action to reverse this trend.

The Federal government began to show interest in the 

problem and acknowledged that it needed to intervene on a 

hands-on basis. The Washington, D.C., office of the U.S. Fish 

and Wildlife Service (USFWS) began to promote a program, 

championed by Dr. Ray Erickson, senior scientist at headquarters, to initiate captive research and propagation of birds 

and mammals. Research was needed to stabilize and recover 

populations in the wild. In order to save endangered species, 

the need was not only to raise birds and mammals in captivity 

but also to release them into the wild to augment populations.

Dr. Erickson envisioned a three-pronged program: a 

section of laboratory investigations; a section of propagation, 

whereby Patuxent Wildlife Research Center (Patuxent) in 

Laurel, MD, would maintain captive populations of animals; 

and the field stations where field biologists would study the 

populations in the wild to determine what actions needed to be 

taken to reverse the downward trends.

Gene Knoder, a biologist with the USFWS stationed 

in Monte Vista Refuge in Colorado, began working with a 

captive population of sandhill cranes (Grus canadensis). Ray 

envisioned that they could be raised at Patuxent because we 

needed to work with a closely related or surrogate species 

whose population was much more abundant than that of the 

endangered whooping crane (Grus americana). Because most 

of these endangered species had rarely or never been bred in 

captivity, Patuxent researchers used the surrogates to develop 

techniques that were likely to be successful in the wild rather 

than to risk working directly with the endangered species.

The whooping crane was a rare species at that time in the 

mid-1960s, and, to the best of our knowledge, its population 

had been reduced to about 14 or 15 birds, although the exact 

number was disputed. Most of these birds wintered along 

the Gulf Coast of Texas and migrated to an unknown part 

of northern Alberta, Canada. In the early 1950s, a biologist 

returning from a forest fire saw a whooping crane with one 

offspring on the ground in Wood Buffalo National Park, which 

extends from northern Alberta into the Northwest Territories.

Through a cooperative effort with the Canadian Wildlife 

Service, the USFWS developed a program whereby we would 

remove one egg from each two-egg clutch and bring it into 

The Endangered Species research team at its peak in early 1980s, at Snowden 

Hall, Patuxent Wildlife Research Center, Laurel, MD, 1980 (left to right, 1st 

row: Ray Erickson, Randy Perry, Paul Sykes, Mike Scott, John Serafin; 2nd 

row: Glen Smart, John Sincock, Noel Snyder, Sandy Wilbur; 3rd row: Jim 

Jacobi, Dave Mech, Dave Ellis, Scott Derrickson; 4th row: Barbara Nichols, 

Jim Carpenter, Cam Kepler; 5th row: Sharon Fox, Jim Wiley, Conrad Hillman; 

not present: George Gee, Gene Cowan). Photo by Paul Sykes, U.S. Fish and 

Wildlife Service.

captivity, where the chicks could be hatched and reared; in this 

way, we could develop a captive breeding population.

Cranes commonly lay two eggs but, because of sibling 

rivalry and food availability, typically only a single chick is 

reared. Therefore, we were salvaging the egg that would theoretically be lost to sibling aggression or starvation.

Beginning in 1967, Ray and I traveled to Wood Buffalo 

National Park, near Fort Chipewyan, Alberta, to meet with 

Canadian Wildlife Service biologist Ernie Kuyt. He was a 
142 The History of Patuxent: America’s Wildlife Research Story

Glen Smart (U.S. Fish and Wildlife Service), Ernie Kuyt (Canadian Wildlife Service), and Ray Erickson (U.S. Fish and Wildlife Service) with eggs, 1967. Photo by U.S. 

Fish and Wildlife Service.

delight to be around, and his knowledge of the area and his 

cooperative nature made him a valuable partner. Because only 

Ernie was authorized to leave the helicopter once we landed at 

a nest, it was his responsibility to collect the egg.

Before we could enter the park, of course, we had to have 

permits. Ray and I were issued permits to enter Wood Buffalo National Park, retrieve the eggs, and bring them out. The 

nesting area is about 80 percent water, consisting mostly of 

small, very shallow ponds. Most of them did not contain fish, 

as the ponds froze solid every winter. Many invertebrates did 

inhabit the ponds, however, and in this general area the cranes 

would nest and raise their young. The birds were typically 

very reluctant to leave the nest as Ernie neared them. On occasion, they even challenged the helicopter, which in itself was 

quite exciting.

We had developed a 1-cubic-foot case made of Styrofoam with a cavity in the middle into which an egg could be 

placed. The plan was for Ernie to put the egg in this Styrofoam 

case and carry it out of the park. If he dropped the case, then, 

optimistically, the egg would not break or be damaged. Ernie 

looked at the case and said, “There’s no way that I’m going 

to carry that thing back and forth.” From then on, every egg 

that was collected from a nest at Wood Buffalo National Park 

was carried out in Ernie’s old woolen sock! As far as I know, 

every egg that ever came out of Wood Buffalo National Park 

got a ride in Ernie’s woolen sock, and, to my knowledge, 

he never dropped an egg. He would go out, examine the 

nest, photograph the nest, select the egg that he felt was less 

liable to hatch, collect the egg, and make his way back to the 

helicopter, where he would relinquish the egg to us. Ray and 

I maintained them in a portable incubator that we had brought 

with us.

Glen Smart and Ray Erickson (U.S. Fish and Wildlife Service) monitoring crane 

eggs, 1967. Photo by U.S. Fish and Wildlife Service.
Endangered Species Research Program

Overview of the Endangered Species Program 143

In the first year (1967), we were going to be flown back 

to Maryland in an executive jet by the Canadian Wildlife Service, or by the Canadian Air Force. However, that was the year 

of the Six-Day War in the Middle East. U Thant, the Secretary 

General of the United Nations, took our plane that year, and 

we had to come back on a commercial flight. Thereafter, we 

returned in first-class accommodations with an executive jet 

each year.

The feather development of each chick was closely 

monitored at Patuxent. By November or December, a chick 

has molted its feathers from the mid-neck down through most 

of the body, but it still has a brown neck and brown wings, 

which are indicative of that time of the year. The birds have 

a continuous molt, so they continue to molt throughout the 

winter. By the time they fly north in the spring, the birds are 

completely white except for the brown head.

Another species we worked with in the 1960s was a small 

race of Canada goose (Branta canadensis) that breeds only in 

the Aleutian Islands off the coast of Alaska. At that time, they 

were called the Aleutian goose (Branta hutchinsii leucopareia). Their population had declined to such an extreme point 

that we thought they were extinct. This belief changed, however, when a refuge manager, Bob Jones (USFWS), made one 

of his lengthy trips into the outer Aleutians in an open dory. 

He was on Buldir Island, which is a relatively small pinnacle 

of rock about 5 × 8 miles in size, with very precipitous cliffs. 

He found a population of about 100 to 150 Aleutian geese 

breeding there.

Ray Erickson (U.S. Fish and Wildlife Service) and chick. Photo from the 

newspaper “Laurel Leader.” Reprinted with permission from The Baltimore 

Sun. All rights reserved.

The Aleutian geese originally were quite common 

throughout the Aleutians. With the interest in fur coats and 

other fur clothing, the arctic fox (Alopex lagopus) furs were 

very valuable and desirable. The Russians fur trappers brought 

foxes to many of these islands, and subsequently the foxes 

reproduced. The trappers would come back at the appropriate 

times and harvest the foxes for furs—it was almost a captive 

fur-animal population. This population of foxes was extremely 

detrimental to the ground-nesting species of birds and other 

animals there. The Aleutian Canada goose was one of the most 

obvious of the birds and it was one of the first to disappear 

because of predation by the foxes. Fortunately for the birds, 

no foxes were brought to Buldir Island because of its precipitous cliffs; fortunately for us, one small area on the northern 

side of Buldir Island is relatively flat, allowing us access to 

the island. We traveled to the island and went ashore in late 

spring. We collected approximately 22 goslings that were 

newly hatched and brought them back to Patuxent to be part of 

our breeding population.

Aleutian Canada geese nest similarly to the other Canada 

geese. We raised many of these birds, but the problem then 

was how to release them back into the wild. In the 1960s, 

the Aleutian Islands National Wildlife Refuge staff was 

actively destroying the foxes on various islands. As an island 

would be cleared of foxes, we would transport some of these 

captive-reared geese to the island and release them, hoping 

that they would disperse and repopulate the island. Unfortunately, although the foxes were gone, there were still many 

bald eagles (Haliaeetus leucocephalus) remaining. Because 

eagles are fond of geese as a dinner item, that plan was less 

than successful.

We tried several alternatives. One solution that worked 

well, once the islands were cleared of foxes, was to go out 

to Buldir Island, capture an adult and the goslings that were 

with that adult, transport them to another island, and release 

them as a family unit. They would then mature, reproduce, 

Crane flock manager Bruce Williams, U.S. Fish and Wildife Service, with 

young whooping crane, 1986. Photo by Matthew C. Perry, U.S. Fish and Wildlife 

Service.
144 The History of Patuxent: America’s Wildlife Research Story

and eventually repopulate the island. Although this population 

was only about 100 to 150 geese when discovered by USFWS 

biologist Bob Jones, it now has skyrocketed to the more than 

200,000 Aleutian Canada geese that are alive today (2016).

The Laboratory Investigations Program at Patuxent 

consisted of professionals in selected areas of expertise. These 

included many of the first people Ray hired, including a nutritionist, a physiologist, and a veterinarian to care for the birds 

in captivity and to cater to their every need. The field portion of the program was staffed originally with six biologists. 

Patuxent biologist Roy Tomlinson went to Arizona to study 

the masked bobwhite quail (Colinus virginianus ridgwayi), 

which is a desert form of bobwhite (Colinus virginianus) that 

was nearly destroyed. The remaining population was found 

mostly in Sonora, Mexico, with additional birds occupying a 

few valleys that extend into southern Arizona.

When cattle herds from Mexico were driven north to 

Tucson to the railheads, they destroyed most of the fragile 

grasslands, which are slow to recover. As a result, over time 

the habitats of the masked bobwhite quail in the United States 

were destroyed.

Roy conducted most of his work in Sonora. He developed 

a technique by which he would go into the desert and find a 

cactus wren (Campylorhynchus brunneicapillus) nest that he 

knew would be lined with feathers that the wrens obtain from 

the desert floor. Roy would examine the nest and identify bird 

species from the feathers that he found. If he found bobwhite 

quail feathers, of course, he would assume they were indicative of the presence of bobwhites in the area.

I went with him when we received the first bobwhites 

from two brothers in Tucson, Jim and Seymour Levy. They 

had been studying the birds on their own, and had a few birds 

in captivity. They let us have three or four pairs. We brought 

them to Patuxent and attempted to breed them. We were 

Andean condor pair in captive breeding pen at Patuxent Wildlife Research 

Center, Laurel, MD. Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.

successful and got a number of eggs. The birds’ fertility was 

quite low, however; the chicks were weak and so inbred that 

production was practically nil. Therefore, we needed to obtain 

some new birds to bolster that breeding population.

I went to northern Mexico with Roy; we trapped about 

20 birds and brought them back to Patuxent. They proved 

easy to breed; we could literally breed them by the hundreds. 

We had no idea how to release them, however, so we began 

by simply placing them in a pen. We allowed them to remain 

there for a few days, where we fed and cared for them, and 

then we opened the door and let them walk out. This plan, 

unfortunately, was not successful because of the many hawks 

and other predators in the area. The bobwhites were quite 

uneducated in the ways of the wild, and, as a result, suffered 

substantial mortality.

Next, we paired neutering females from a captive Texas 

bobwhite quail population with male masked bobwhites so 

they would not hybridize. As chicks hatched in the incubator, 

we would put 12 to 15 with one of these pairs, take them to the 

desert, and release them. Again, results were similar to those 

of the earlier releases, but with one exception: the mesh on the 

pens was large enough that the babies could get out and begin 

to forage a little on their own, but the parents would always 

call them back. We would keep them there for a week or so, 

until they became familiar with the area, and then release 

them. We did build a stable population for a while but, because 

of the inadequate habitat, I do not think that population has 

been very successful. I believe there are still a few quail in 

Arizona and a few in Sonora.

The California condor (Gymnogyps californianus) population was 12 or 13 birds, and the appropriate course of action 

regarding the species was a very controversial subject in the 

area of their native habitat. One faction of biologists felt very 

strongly that we should leave the birds alone to die in dignity, 

Andean condors with backpack transmitters, Patuxent Wildlife Research 

Center, Laurel, MD. Photo by Noel F.R. Snyder, U.S. Fish and Wildlife Service.
Endangered Species Research Program

Overview of the Endangered Species Program 145

and not bring them into captivity, where they would be no longer condors at all, but similar to captive chickens. The other 

faction felt that, in order to save them, we needed to bring 

all condors into captivity, breed them, and eventually release 

them back into the wild.

When the population began to decline precipitously, the 

State of California indicated that Patuxent could catch all of 

the birds and bring them into captivity. However, no California condors were allowed to leave the State of California. 

Unfortunately, then, we were not able to bring them back 

to Patuxent.

However, we were able to reach a compromise with 

the San Diego Zoo and the Los Angeles Zoo. The zoos built 

facilities that were off exhibit to the public and began to raise 

California condors. At Patuxent, we were studying the closely 

related Andean condor (Vultur gryphus). We found that by 

removing eggs as they were laid, we could obtain multiple 

clutches in a given year (a clutch being one egg in condors). 

Typically, we would get three or four eggs from a female, but 

I believe we once got as many as nine. By removing eggs, we 

could greatly increase the productivity of a given condor pair. 

Snyder (2016) discusses the details of this negotiation on the 

fate of the condors in depth.

The black-footed ferret (Mustela nigripes) was another 

animal we studied at Patuxent, but we had little success with 

it. Because of other priorities, we reduced the effort we were 

investing in this program, and it was eventually taken over 

by a consortium of State wildlife agencies and zoos with the 

guidance of the USFWS. Thousands of captive-raised blackfooted ferrets have been released in eight western states, and 

also in parts of Canada and Mexico (National Black-Footed 

Ferret Conservation Center, n.d.; U.S. Fish and Wildlife 

Service, 2015).

Hawaii was home to a multitude of endangered species. 

Many of them were forest birds, including the Hawaiian crow 

(Corvus hawaiiensis), which was rare. John Sincock was the 

first biologist hired by Patuxent for that program. He began 

studying this and a variety of other species. The Hawaiian 

research program was difficult to conduct because of the terrain, but the researchers involved made great progress in the 

conservation of endangered species on the islands (Scott and 

Kepler, 2016).

Noel Snyder was the first Patuxent biologist to work on 

the Puerto Rican parrot (Amazona vittata) in Puerto Rico. This 

bird’s population was very low—fewer than 20. We worked 

with this species briefly at Patuxent, after which Region 4 of 

the U.S. Fish and Wildlife Service and the Commonwealth of 

Puerto Rico became involved and set up a captive breeding 

population and facilities in Puerto Rico. They are doing well 

with them and in 2011 had about 500 birds, either in captivity 

or in one of two wild populations.

One of the first things that we found to be a limiting 

factor for the parrot was the curved-bill thrasher (Margarops 

fuscatus). The thrashers would go into the parrot nesting cavities, pierce the eggs, throw them out, and then use the nest 

site themselves. Dr. James Wiley, Patuxent (Wiley, 2016), 

presents a more detailed discussion of the Puerto Rican parrot 

research project.

Patuxent researcher Paul Sykes worked on snail kites 

(Rostrhamus sociabilis) and dusky seaside sparrows (Ammodramus maritimus nigrescens) in Florida. Snail kites feed 

almost exclusively on the apple snail. The kite population is 

currently (2016) doing well. Unfortunately, the dusky seaside 

sparrows did not fare as well, and actually became extinct during the period when Paul was working on them. 

Paul Sykes is also well known for his studies with other 

endangered species, including the Kirtland’s warbler (Setophaga kirtlandii) and the ivory-billed woodpecker (Campephilus 

principalis). A study of the Kirtland’s warbler was initiated in 

1985 on the bird’s wintering grounds in the Bahamas, West 

Indies, as part of Patuxent’s Endangered Wildlife Research 

Program. On the morning of February 26, Sykes and Paul 

Sievert captured an adult male Kirtland’s warbler in a mist net 

Paul Sykes, U.S. Fish and Wildlife Service, with a recently banded Kirtland’s 

warbler, Eleuthera, Bahamas, West Indies, 1985. Photo by Paul Sievert, U.S. 

Fish and Wildlife Service.
146 The History of Patuxent: America’s Wildlife Research Story

Wolf with collar-mounted transmitter being tracked by David Mech, U.S. Fish 

and Wildlife Service, in Minnesota. Photo by U.S. Fish and Wildlife Service.

in a patch of low, dense shrub/scrub dominated by buttonsage 

(Lantana involucrata). The site was 1.3 miles north of the 

town of Governor’s Harbour in the middle of the island of 

Eleuthera. The warbler was uniquely color banded and various 

morphological data were recorded, but in the excitement it 

managed to get free before it was photographed. Sykes named 

the bird “The Governor” for the proximity of its winter territory to Governor’s Harbour. The warbler was recaptured at 

the same locality on February 28 and photographs were taken, 

including the one shown here, with the warbler being firmly 

held by Sykes. To the best of our knowledge, this was the 

first time a live Kirtland’s warbler was photographed in the 

Bahamas, and at that time it was only the second banding of 

the species in the islands.

Dr. David Mech studied gray wolves (Canis lupus) in 

northern Minnesota and Michigan. Dave was a student at 

Purdue University when he studied wolves on Isle Royale in 

Michigan. He became very well known because of his studies, and subsequently was hired by the USFWS as the field 

biologist to study this population. Dave has been working with 

these animals since the early 1960s, and continues to work on 

wolves in that area. He presents major aspects of his studies 

together with supporting data in the chapter titled “Patuxent’s 

Long-Term Research on Wolves,” farther on in this report 

(Mech, 2016).

References Cited

Mech, L.D., 2016, Patuxent’s long-term research on wolves, in

Perry, M.C., ed., The history of Patuxent—America’s wildlife research story: U.S. Geological Survey Circular 1422, 

p. 197–212. [Also available at https://doi.org/10.3133/

cir1422.]

National Black-Footed Ferret Conservation Center, n.d., 

Black-footed ferret connections at blackfootedferret.org—

Captive breeding, accessed June 3, 2016, at http://blackfootedferret.org/captive-breeding/.

Scott, J.M., and Kepler, C.B., 2016, Endangered species 

research in Hawaii—The early years (1965–87), in Perry, 

M.C., ed., The history of Patuxent—America’s wildlife 

research story: U.S. Geological Survey Circular 1422, 

p. 183–196. [Also available at https://doi.org/10.3133/

cir1422.]

Snyder, N.F.R., 2016, Conserving California condors in 

the 1980s, in Perry, M.C., ed., The history of Patuxent—

America’s wildlife research story: U.S. Geological Survey 

Circular 1422, p. 147–156. [Also available at https://doi.

org/10.3133/cir1422.]

U.S. Fish and Wildlife Service, 2015, Black-footed ferret—

Mustela nigripes: U.S. Fish and Wildlife Service fact sheet, 

Region 6 (Mountain-Prairie Region), accessed June 3, 2016, 

at https://www.fws.gov/mountain-prairie/factsheets/BlackFooted-Ferret.pdf.

Wiley, J.W., 2016, Endangered species research in the 

Caribbean, in Perry, M.C., ed., The history of Patuxent—

America’s wildlife research story: U.S. Geological Survey 

Circular 1422, p. 157–170. [Also available at https://doi.

org/10.3133/cir1422.]
Endangered Species Research Program

Conserving California Condors in the 1980s

Noel F.R. Snyder

By the late 1970s, the California condor (Gymnogyps 

californianus) was in serious trouble, with probably no more 

than about 30 birds left in existence, all in a mountainous 

region just north of Los Angeles that is vegetated mainly in 

chaparral and grasslands. All estimates of population size and 

trends offered since the early condor studies by Carl Koford 

in the 1930s and 1940s indicated a continuing decline toward 

extinction, and it appeared that few years were left before the 

species would be gone (see Koford, 1953; Wilbur, 1978). Evidently, the conservation steps that had been taken, including 

the creation of a number of important condor reserves, were 

not resulting in recovery of the species.

Patuxent Wildlife Research Center (Patuxent) in Laurel, 

MD, had been involved in studies of the species since the mid1960s, beginning with the efforts of Fred Sibley from 1966 to 

1969 and continuing with the work of Sanford Wilbur through 

the 1970s (Sibley, 1968; Wilbur, 1978). The causes of the 

decline remained controversial and difficult to resolve, however, because of the enormous practical difficulties involved in 

studying such a rare and highly mobile species in exceedingly 

rugged terrain, especially when research was limited by political constraints to passive, nonintensive techniques and funding 

for research was minimal.

By 1980, no functioning captive population of California 

condors was yet in existence, largely because of the consistent 

opposition of biologist Carl Koford and other early researchers 

of the species, who believed a captive flock would represent 

an abandonment of efforts to conserve the wild population. 

Nevertheless, Patuxent had established a surrogate captive 

population of Andean condors (Vultur gryphus) in anticipation 

of a need for captive breeding of the California species and 

had been successful in demonstrating routine capacities of the 

Andean birds to lay replacement eggs—thus greatly increasing 

their reproductive potential under intensive management (see 

Erickson and Carpenter, 1983).

Fortunately, two outside evaluations of the recovery 

program were conducted in 1978—one by Jared Verner of the 

U.S. Forest Service and one by a combined Audubon-American Ornithologists’ Union panel chaired by Robert Ricklefs of 

the University of Pennsylvania (Verner, 1978; Ricklefs, 1978). 

Both evaluations strongly recommended the initiation of 

intensive research and management techniques such as radiotelemetry and captive breeding. These reports were crucial in 

mobilizing the National Audubon Society to mount a lobbying 

California condor, Ventura County, CA, 1980s. Photo by David Clendenen, U.S. 

Fish and Wildlife Service.

effort with Congress that resulted in the creation in 1979 of a 

well-funded, final intensive program on behalf of the condor.

On-the-ground operations of the new program were 

initiated in 1980 and were led by Patuxent in collaboration 

with the National Audubon Society, but there were many 

other cooperators, including the California Department of 

Fish and Game, the U.S. Forest Service, the Bureau of Land 

Management (BLM), the Los Angeles and San Diego Zoos, 

and several California universities and research institutions. 
148 The History of Patuxent: America’s Wildlife Research Story

Sespe Condor Sanctuary, Ventura County, CA, 1980s. Photo by Noel F.R. 

Snyder, U.S. Fish and Wildlife Service.

My personal involvement in condor research began at this 

point as field leader of Patuxent’s condor program; John 

Ogden became the principal leader of National Audubon’s 

field efforts. In this presentation, I briefly review the cooperative studies that were conducted in the 1980s to identify 

the primary causes of decline of the wild population and the 

cooperative efforts to create a viable captive population, as 

well as certain aspects of subsequent releases of captives to the 

wild—subjects covered in more detail in Snyder and Snyder 

(2000, 2005) and Snyder (2007).

Research on Causes of Decline in the 

1980s

At the start of the new intensive program in 1980, there 

were three primary competing hypotheses under consideration regarding the main cause of the decline of the California 

condor. The first was the position of Miller and the McMillan brothers (1965), who had studied the species in the early 

1960s and believed that the bird was breeding normally, but 

was suffering from overwhelming mortality stress from illegal 

shooting and from poisoning campaigns, especially ground 

squirrel poisoning using Compound 1080 (an organofluorine pesticide). The second hypothesis was the proposal of 

Wilbur (1978) that the species was suffering from declining 

carrion food supplies and had largely stopped breeding, with 

only two pairs still known to be actively reproducing in the 

late 1970s. The third hypothesis was that of Kiff and others (1979) that the condor was suffering major stress from 

dichlorodiphenyldichloroethylene (DDE) contamination of 

its food supplies, which apparently had caused a more than 

30-percent decline in eggshell thickness in the 1960s and 

could still be causing reproductive effects such as frequent egg 

breakage and lowered reproductive output.

All three of these hypotheses were plausible, but all suffered from only fragmentary supporting evidence and none 

was fully persuasive, though there was special concern about 

the potential effects of DDE, as the extent of eggshell thinning 

apparently had been severe in the 1960s. To resolve which factors were truly responsible for the condor’s continuing decline, 

so that conservation could proceed intelligently, comprehensive studies of contaminant levels, breeding productivity, 

mortality rates, and causes of mortality in the wild population 

were needed. In pursuit of these goals, diverse research activities were planned, many of them aided by radiotelemetry.

Intensive basic biological studies were especially crucial 

at this stage because it was not clear that all potentially important causes of the decline had been identified. One source of 

mortality that was not recognized by Koford, Miller, and the 

McMillans, or by any other historical condor researcher, was 

lead poisoning resulting from the birds’ ingestion of ammunition fragments in hunter-shot carcasses. Locke and others 

(1969) at Patuxent had published a paper on a captive Andean 

condor dying from feeding on an ammunition-contaminated 

carcass, and there was every reason to suspect frequent 

exposure of California condors to lead-contaminated carcasses 

because of the large amount of hunting going on in the State. 

Unless a substantial number of condors could be radiotagged 

so that dead birds could be found promptly and comprehensively necropsied, it could be difficult to determine the severity of the threat of lead poisoning.

Crucial to evaluating all hypotheses was the development 

of improved methods of censusing the wild population. From 

1965 until 1980, estimates of the size of the condor population were based largely on the annual simultaneous October 

Survey during which people were stationed at overlooks 
Endangered Species Research Program

Conserving California Condors in the 1980s 149

of known condor concentration areas throughout the range 

(see Mallette and Borneman, 1966). This methodology was 

relatively crude because of difficulties involved in recognizing 

and eliminating duplicate sightings of birds that moved from 

one observation point to another and because only a modest 

fraction of the range of the species was covered by accessible 

observation points. Program cooperators initially anticipated 

that if many of the birds in the wild population could be radiotagged, the uncertainties in future October Surveys could be 

substantially reduced. Instead, a more reliable and informative 

method of censusing evolved through the extensive use of a 

less advanced technology—photography of flying birds (see 

Snyder and Johnson, 1985). Early success with this new photographic method led to abandonment of the October Survey 

after 1981.

Each individual condor was discovered to be unique in 

its flight feather pattern as a result of unique feather damage 

events and highly variable molt of feathers (Snyder and others, 

1987). Because feather patterns changed only slowly through 

time, when a sufficient number of photos of flying condors had 

been taken throughout the condor range, all individuals could 

be continuously recognized and counted. The photos were 

sorted chronologically into files representing the histories of 

individual birds—histories that revealed not only the movements of the birds but also how many birds were present on 

specific dates. Much of the credit for this effort goes to Eric 

California condor with distinctive feather damage and molt, southwestern 

California, 1980s. Photo by Jesse Grantham, U.S. Fish and Wildlife Service.

Noel F.R. Snyder (left), U.S. Fish and Wildlife Service, and Eric Johnson, California Polytechnic State University, San Luis Obispo, CA, sorting condor 

photos. 1982. Photo by Helen A. Snyder, U.S. Fish and Wildlife Service.
150 The History of Patuxent: America’s Wildlife Research Story

Johnson and his students at California Polytechnic State University in San Luis Obispo, but essentially everyone involved 

in studying condors contributed to its success. By 1982, it was 

possible for the first time to census the wild population accurately and continuously. 

The photographic censusing revealed a very rapid decline 

in the remnant population associated with very high mortality 

rates. From late 1982 to mid-1985, the population decreased in 

annual decrements from 21 to 19 to 15 to 9 known individuals, and the average annual mortality rate for the population 

was more than 25 percent per year, a rate far greater than any 

that could allow population stability or growth under known or 

potential reproductive rates (see Meretsky and others, 2000). 

Such figures clearly indicated a grave crisis in survival of the 

wild population irrespective of any potential reproductive 

problems. Unexpectedly, the mortality rate was slightly higher 

in full adults (26.8 percent) than in immatures (22.2 percent), 

a finding that was important in identifying potential causes of 

decline, as discussed below.

While photographic censusing was underway, a major 

effort also was made to find all nests in the wild population 

Condor nest in giant sequoia, Ventura County, CA, 1984. Photo by Helen A. 

Snyder, U.S. Fish and Wildlife Service.

and to directly track their rates of success and causes of failure. To this end, a staff of nest observers was assembled that 

grew to 12 individuals by the time the program was several 

years old. All nesting pairs were eventually located and studied on a continuing basis despite major logistical difficulties.

Most condor nests were caves in cliffs, but one active 

study site was discovered in a burned-out hollow of a giant 

sequoia. Nests were generally hard to find because the breeding pairs were dispersed over an extensive and rugged terrain 

and visited their nests infrequently. To find active nests of 

pairs that were not radiotagged, we employed multiday vigils 

at strategic lookout points within potential nesting areas, following the movements of prospective nesting birds through 

telescopes, looking for aerial signs of nesting behavior, and 

then gradually homing in on the locations of nests. Once 

active nests had been located, they were given steady daylight coverage from distant observation points until the young 

fledged or the nests failed. Twenty-three of the 25 active nests 

found during studies in the 1980s were sites that had not been 

previously documented as condor nests by earlier researchers, 

but most of these nests were internally plastered with excrement layers, indicating repeated use in earlier years rather than 

new nests.

As summarized in Snyder and Snyder (2000, 2005), the 

studies of breeding biology in the 1980s resulted in the following major conclusions:

1. Most adults were paired and were breeders, although two 

of the pairs found were likely pairs of homosexual males 

that had nest sites but laid no eggs. These pairs likely 

resulted from the existence of a slightly skewed sex ratio 

among adults. Other than these two pairs, there were no 

generic signs of a failure of adults to breed, and all clearly 

heterosexual adult pairs were breeding consistently except 

when burdened with dependent fledglings. Even when the 

total population of condors in the wild, including immatures, had declined to just 15 individuals in 1984, five 

Observation point for locating condor nests in Sespe Condor Sanctuary, 

Ventura County, CA, 1980s. Photo by Noel F.R. Snyder, U.S. Fish and Wildlife 

Service.
Endangered Species Research Program

Conserving California Condors in the 1980s 151

Pair flight display of California condors, southwestern California, 1980s. Photo 

by Noel F.R. Snyder, U.S. Fish and Wildlife Service.

pairs of condors—two-thirds of the population—were still 

actively breeding.

2. Nesting efforts were reasonably successful, resulting in 

fledglings in nearly half the nesting attempts, a rate similar to those documented for other solitary nesting vultures. 

Nestlings were consistently well fed, and the survival 

rate of nestlings to fledging was high. Most nest failures 

occurred at the egg stage.

3. Clutch size was invariably a single egg, and nesting pairs 

readily laid replacement eggs when early-laid eggs failed 

as a result of predation or were taken into captivity.

4. Pairs that produced a fledgling in one year were capable 

of breeding late in the next spring, but then typically 

skipped breeding in the third year while they still were 

tending a dependent fledgling from late in the second 

year. Thus, successful pairs were evidently capable of 

producing two young in 3 years.

5. The primary cause of the moderate number of nesting 

failures was predation by common ravens (Corvus corax) 

on eggs. There were no persuasive signs of reproductive failure to DDE contamination, such as chronic egg 

breakage unrelated to raven predation. Neither was there 

any evidence of chronic failure of eggs to hatch after fullterm incubation. As documented in Snyder and Meretsky 

(2003), the correlation between eggshell thickness and 

DDE levels in eggshell membranes was weak; instead, 

eggshell thickness was highly correlated with egg size, 

indicating that the thin eggshell fragments collected in 

the 1960s could have come from relatively small eggs 

rather than from structurally weak eggs. One female in the 

1980s was laying eggs whose shell thickness was nearly 

25 percent less than the historical mean, but her eggs were 

also very small and she was the most successful female 

of her period in producing fledglings. Her eggshells were 

of an appropriate thickness for the size of her eggs, and 

there is no good evidence that she suffered from structurally weak eggs. The apparently severe shell thinning of 

the 1960s could have been largely an artifact of small egg 

size in the few females sampled, which may well have 

included the small-egged female studied in the 1980s. 

Unfortunately, egg size was not documented for any of the 

eggs in the 1960s but, consistent with egg size being the 

primary determinant of shell thickness, nesting success in 

the 1960s, as documented by Fred Sibley (1968) and in a 

later analysis by Snyder (1983), was not distinguishable 

from nesting success in the 1980s, and was reasonably 

strong.

Therefore, the intensive studies of the 1980s yielded no 

clear evidence of major breeding problems due to food stress, 

DDE contamination, nest predation, or any other factors, but 

instead indicated that excessive mortality of free-flying adults 

and immatures was the primary cause of population decline. 

Moreover, judging from the eight dark-headed immatures 

(about one-third of the population) whose existence we were 

fortuitously able to document at the start of the intensive program, there had been no major problems with reproduction at 

least as far back as the late 1970s.

The intensive studies of the 1980s, therefore, were most 

supportive of the hypothesis of Miller and others (1965) that 

the primary problems of the species were mortality factors, not 

reproductive factors (Wilbur, 2004). However, accumulating 

evidence (Snyder, 2007) indicated that the single most important mortality factor was not shooting or the sorts of poisoning described by these researchers, but was instead the kind 

of poisoning we had feared might be of primary importance 

as described by Locke and his collaborators in 1969—lead 

poisoning (Locke and others, 1969; Snyder and Snyder, 2000, 

2005; Snyder, 2007).

Probably just as a result of chance, the condors we were 

able to radiotag in the 1980s had much better survival rates 

than the condors that were not radiotagged, so that relatively 

few dead condors were recovered for necropsy, and information on specific mortality factors was accumulated only 

slowly. Nevertheless, of the four free-flying condors that were 

recovered dead or dying in the 1980s, three were found to be 

victims of lead poisoning. The fourth was a victim of cyanide 

poisoning, presumably from a coyote trap. Poisoning from 

contaminated food is one of the few causes of mortality that 

can be expected to affect adults as severely as immatures and, 

therefore, it provides a plausible explanation for the nearly 

identical mortality rates found for these age classes in the 

1980s. In contrast, if the population had been suffering mainly 

from shooting or collision mortality, one would have expected 

the mortality rate of relatively unwary and clumsy immatures 

to greatly exceed that of adults–a situation found in populations of many large raptorial birds.

When the first well-documented case of lead poisoning 

occurred in 1984, there was not yet nearly enough evidence 

to conclude that lead might be the most important cause of 
152 The History of Patuxent: America’s Wildlife Research Story

John Schmitt, U.S. Fish and Wildlife Service, with lead-poisoned condor, 1980s. 

Photo by Helen A. Snyder, U.S. Fish and Wildlife Service.

the species’ decline. However, when two more condors were 

diagnosed as victims of lead poisoning in the next 1-1/2 years 

and a full 40 percent of the wild population was lost over the 

winter of 1984–85, a belief that the species might be in deep 

trouble from this source became tenable, first for the California Fish and Game Commission and ultimately for the U.S. 

Fish and Wildlife Service (USFWS). This belief was the major 

force that led both agencies to decide that the last remaining 

wild condors should be brought into captivity—an action that 

was accomplished by early 1987.

The problem of lead poisoning from ammunition fragments remains unsolved today (2016) despite the accumulation of supporting data indicating that lead poisoning from 

ammunitions has been a major problem for the condor, as well 

as for other wildlife species such as swans and eagles (see 

discussion in Snyder [2007]).

The supporting data for condor lead poisonings have 

come from ongoing releases of captive condors to the wild 

that have been conducted since the early 1990s (Jane Hendron, 

U.S. Fish and Wildlife Service, unpub. report, 1998; Snyder 

and Snyder, 1989, 2000). These releases have been followed 

by many lead-poisoning mortalities plus many more nearmortalities from lead poisoning that have been countered by 

returning birds to captivity for emergency chelation treatment. 

One can question why releases have been attempted in the 

absence of mitigation or removal of the main cause of extirpation, but in any event they have confirmed beyond reasonable 

doubt that lead poisoning continues to be the major threat to 

wild populations. The release program in Arizona alone has 

performed considerably more than 150 emergency chelations 

of lead-poisoned birds since releases began in 1996 (see Walters and others [2010]). In spite of such rescue efforts, however, lead poisoning remains the principal source of mortality 

in the release programs (see Finkelstein and others [2012], 

Rideout and others [2012]).

Formation of a Captive Flock

Formation of a captive flock of condors involved capturing wild condors from the egg stage to the adult stage. This 

process faced opposition from individuals and some conservation organizations, as described in detail by Wilbur (2004) 

and Syder and Snyder (2000, 2005). The process could have 

been completed with only minimal effects on the wild population if it had been started early enough and had been limited 

to collecting eggs early in the breeding season, leaving time 

for pairs to recycle with replacement eggs (Snyder and Snyder, 2000, 2005). A captive flock was established at the Los 

Angeles Zoo in 1982, and only about half the captive flock 

was taken as eggs. The remainder consisted of nestlings and 

free-flying birds trapped from the wild, after it became clear 

that the wild population was inviable and about to disappear 

completely.

At the start of the intensive program, the California 

condor had never been bred in captivity and no members of 

the species were in confinement except Topatopa, a wild male 

fledgling that had come into the Los Angeles Zoo with an 

injured foot in 1967. Unfortunately, taking eggs from the wild 

population was politically impossible until 1983. Replacement 

egg-laying was well known for captive Andean condors by the 

start of the intensive program, but, because at that time such 

layings had not been clearly documented in the California condor permit, clearance to use this approach could not be secured 

from State and Federal authorities, although it seemed likely 

that California condors would have the same capacities.

Instead, the captive acquisition program was initially 

limited by permit restrictions to obtaining an unpaired female 

bird to pair with Topatopa, the only California condor already 

in captivity. This was a dubious strategy at best because a captive population consisting of one pair was far from adequate 

to sustain or significantly bolster the species and because 

Topatopa was known to be a behaviorally compromised bird. 

Topatopa had been held in isolation from his species since 

the late 1960s, and his potential for breeding was highly 

questionable because of his strong orientation to humans. 

Further, identifying an unpaired female in the wild population and capturing her posed some strong practical difficulties 

at that time, as condors cannot be sexed externally and were 

not yet individually identifiable. Efforts to obtain a potential 
Endangered Species Research Program

Conserving California Condors in the 1980s 153

mate for Topatopa were fruitless during the first 3 years of the 

intensive program.

Fortunately, the intensive observations of nesting pairs in 

1982 allowed conclusive documentation of a case of natural 

replacement clutching in the wild, eliminating the roadblock 

to forming a captive flock from eggs. Proof of natural replacement clutching was arguably the most important and beneficial 

result of the intensive nesting studies of the 1980s. It now 

became possible to take eggs from all breeding pairs in the 

wild and to artificially incubate them at the San Diego Zoo, 

while the pairs recycled with replacement eggs in the wild. In 

the first year of operations—1983—four eggs were taken from 

three pairs and all hatched successfully, producing four surviving young. Together with two chicks produced in the wild, six 

young were produced that year, in contrast to the typical average of two young produced in previous years. Results were 

even better in 1984, when five pairs produced seven surviving young. Thus, the removal of eggs for artificial incubation 

demonstrably increased overall reproduction of the remaining 

wild birds largely through replacement layings. Indeed, all 

pairs but one ultimately demonstrated a potential for double 

clutching within a single breeding season; three pairs even 

demonstrated a capacity for triple clutching (see Snyder and 

Hamber [1985]).

Thus, by late 1984, a captive flock was being rapidly 

assembled, and a consensus developed that in the following year the taking of eggs should continue, but that it might 

be possible to channel some of the production possible with 

replacement clutching into sustaining the wild population with 

an early release program. This hope was based on an assumption of reasonably good survival of the existing wild breeding 

pairs. The recovery team developed a plan approved by all 

cooperators in the program by which a pair would begin to 

contribute to a release program once five progeny had been 

obtained from the pair for permanent holding in the captive 

flock. By late 1984, two pairs were each represented by five 

progeny in captivity, so it appeared that both these pairs could 

produce young for a release program starting in 1985 if they 

survived to the 1985 breeding season. At that point, causes 

and rates of decline for the wild population were still not well 

established, and there was every reason to continue to attempt 

to maintain the wild population. Most program participants 

were looking forward to splitting the benefits of replacement 

clutching between the wild and captive populations in 1985.

Unfortunately, mortality of breeding pairs proved catastrophic over the winter of 1984–85, and only one of the five 

pairs active in 1984 survived to lay eggs in 1985. This was 

not one of the pairs with five progeny in captivity. Moreover, 

of the 15 birds in the wild population in late 1984, only 9 

were still alive by mid-1985—a 40-percent decline in the wild 

population in just a few months. This extremely high mortality was observed mostly in birds that were never recovered, so 

causes of mortality were for the most part unknown, although 

one of the lost birds was recovered moribund and was determined to be another victim of lead poisoning. The failure of 

the assumptions underlying an early release program to hold 

true during the winter of l984–85 led to one of the most contentious periods of debate over strategies in the history of the 

condor program.

On one side of the debate were those who, like me, 

believed that it was wisest and most conservative to conclude 

from recent events that the wild population was truly inviable and that release of captives into such a population would 

actually decrease the chances of ultimate recovery of the species by compromising the viability of the captive population. 

It appeared that lead poisoning could, in fact, be the major 

problem and that any hope that this problem could be reversed 

before the species became extinct in the wild was unrealistic. 

Meanwhile, the captive flock was neither large enough nor 

genetically diverse enough to ensure viability—at that time 

it was made up almost entirely of the progeny of a few pairs. 

Capturing the last free-flying birds might at least achieve a 

viable captive population and allow time to correct the lead 

problem, whereas leaving them in the wild would almost 

certainly be to watch them, and possibly the species, perish 

quickly with no long-term benefit. The California Fish and 

Game Commission opposed both releases and leaving birds in 

the wild (see discussion in Snyder and Snyder [2005]).

On the other side of the debate were people and organizations that argued that the recent high mortality was likely 

atypical and that it was crucial to maintain the wild population 

as long as possible by proceeding with releases even though 

the minimal conditions established by the recovery team for 

releases could not be met. Without birds in the wild, it was 

argued, it would not be possible to maintain existing and prospective condor reserves or funding for a continuing condor 

program (Wilbur, 2004).

The opposing points of view resulted in a stalemate 

through much of 1985. No releases were conducted because 

they required approval at both the Federal and State levels, which was not obtainable. The only action agreed upon 

through extensive negotiation was that three of the remaining 

nine birds in the wild could be brought into captivity. These 

three birds were trapped into captivity in the summer of 1985.

The position of the recovery team on capture of the last 

wild birds was initially ambivalent, although in early 1985 the 

team quickly reached a consensus that releases should not be 

initiated. However, by the summer of 1985, the team recommended that at least three of the remaining six wild birds 

should be taken captive, and by the fall of 1985, the team was 

in full agreement with the State of California’s preferred position that all wild birds should be taken captive. This agreement 

developed in part because of a vigorous debate on the issue 

held at the International Vulture Symposium in Sacramento in 

November of that year.

Then, in early December 1985, the USFWS reversed 

its position and the long debate was finally resolved with a 

consensus of the USFWS with the State of California and 

the recovery team that all wild birds should be taken captive 

and that no near-term releases should be conducted (Snyder 

and Snyder, 2000, 2005). This agreement clearly came about 

because another condor still in the wild contracted terminal 
154 The History of Patuxent: America’s Wildlife Research Story

lead poisoning at this point, making it increasingly plausible 

that the major problem in the wild was indeed lead poisoning, 

a very difficult problem to solve quickly.

However, agreement that the last birds should come into 

captivity still had to clear two more hurdles: (1) a lawsuit 

filed by the National Audubon Society to prevent trapping 

of the last wild birds, and (2) objections to trapping the last 

wild birds from a group of Native Americans. The lawsuit 

and Native American objections were successfully resolved 

by mid-1986, and the last birds were trapped into captivity 

by early 1987, yielding an initial captive flock of 27 birds, 

consisting of 13 males and 14 females (Snyder and Snyder, 

2000, 2005).

As hoped, the California condor proved adaptable to 

captive conditions and has bred readily in confinement, with 

all birds initially taken captive eventually becoming captive 

breeders—even Topatopa, although he was one of the very 

last to begin reproduction. The number of condors currently in 

existence now totals near 400, about half of them in the wild 

and half in captivity. This total is far greater than the low point 

of 22 individuals reached in 1982 before a captive program 

was launched (Snyder and Snyder, 2005).

Releases and Prospects for Viable 

Wild Populations

Following the rapid success in captive breeding, releases 

to the wild were begun in the early 1990s, first in southern 

California, then later in Arizona, other locations in California, 

and Baja California. Unfortunately, like the historical wild 

population in the 20th century, none of these populations 

has yet achieved viability, even with intensive management. 

Problems have been diverse but, as discussed above and in 

Snyder (2007), Walters and others (2010), Rideout and others 

(2012), and Finkelstein and others (2012), lead poisoning soon 

emerged again to dominate the list of negative factors. These 

authors agree that viable, self-sustaining wild populations 

likely will never be achieved unless the lead poisoning threat 

is fully addressed.

Other than a long-standing ban on lead shot in waterfowl 

hunting, lead ammunitions have not been banned anywhere 

in the United States except in the condor range in California, 

where a ban was instituted in 2007 and expanded in 2013. 

Elsewhere, prospective bans face continuing political opposition from interest groups fearful of potential consequences 

(see discussion in Snyder [2007]).

As was widely anticipated, the California ban on lead 

ammunitions, though an important step symbolically, has not 

ended condor lead poisonings in the State, perhaps because 

lead ammunitions are still readily obtainable in other parts of 

the country. Lead poisoning may continue if the supply of lead 

ammunitions is not fully removed

In favoring a ban on the use of lead ammunitions, most 

condor conservationists have not sought the end of hunting 

activities, but only the end of hunting activities using toxic 

ammunitions. In fact, hunting activities, so long as they are 

conducted with nontoxic ammunitions, may prove to be crucially beneficial for condor conservation in many regions by 

providing an adequate long-term carrion food supply (Snyder 

and Snyder, 2000, 2005).

Final Remarks

Although a major threat, lead poisoning is not the only 

source of the excessive mortality of wild California condors, 

and excessive mortality is not the only problem associated 

with releases. Discussions of other threats to the species are 

found in Mee and Hall (2007) and Walters and others (2010). 

The release population along the central California coast, for 

Condor release site, Sespe Sanctuary, Ventura County, CA, 1980s. Photo by Noel F.R. Snyder, U.S. Fish and 

Wildlife Service.
Endangered Species Research Program

Conserving California Condors in the 1980s 155

example, has recently been experiencing reproductive problems that are reflected in low hatchability of eggs (Burnett and 

others, 2013). Causes of the low hatchability have not been 

identified conclusively, although there are concerns that it may 

stem from these birds feeding heavily on carcasses of marine 

mammals, which are known to carry high levels of many 

contaminants (Marine Mammal Commission, 1999). Which 

contaminant might be involved is as yet unclear.

Another problem that is currently being vigorously 

debated is the need to ensure the future existence of optimal 

foraging regions for the species (Snyder and Snyder, 2005). 

Nesting habitats of the condor are mostly well-protected 

National Forest lands, but foraging habitats are largely private 

ranchlands that are being progressively lost to development. 

Arguably, the most important foraging region for the historical wild population and for the release population in southern 

California lies on the Tejon Ranch in Kern County, CA, parts 

of which were designated Critical Habitat for the species by 

the USFWS in 1976. The Tejon Ranch owners are now (2016) 

proposing major housing developments that would directly 

compromise a substantial portion of this Critical Habitat (Snyder and Snyder, 2005, p. 175). These development plans, if 

implemented, could have major adverse effects on the species.

Altogether, the condor program was one of the longest 

and most arduous efforts in Patuxent’s Endangered Wildlife 

Research Program. That the condor is still with us is a great 

credit to the USFWS, and although wild populations of the 

species are not yet self-sustaining, there is reason to hope that 

this goal can be reached if the commitment shown by involved 

agencies in the past can be sustained, and the remaining 

obstacles to full recovery can be successfully addressed.

References Cited

Burnett, L.J., Sorenson, K.J., Brandt, Joseph, Sandhaus, E.A., 

Ciani, Deborah, Clark, Michael, David, Chandra, Theule, 

Jenny, Kasielke, Susie, and Risebrough, R.W., 2013, Eggshell thinning and depressed hatching success of California condors reintroduced to central California: Condor, 

v. 115, no. 3, p. 477–491. [Also available at http://dx.doi.

org/10.1525/cond.2013.110150.]

Erickson, R.C., and Carpenter, J.W., 1983, Captive condor 

propagation and recommended release procedures, in

Wilbur, S.R., and Jackson, J.A., eds., Vulture biology and 

management: Berkeley, CA, University of California Press, 

p. 385–399.

Finkelstein, M.E., Doak, D.F., George, Daniel, Burnett, Joe, 

Brandt, Joseph, Church, Molly, Grantham, Jesse, and Smith, 

D.R., 2012, Lead poisoning and the deceptive recovery of 

the critically endangered California condor: Proceedings of 

the National Academy of Sciences of the United States of 

America, v. 109, no. 28, p. 11449–11454. [Also available at 

http://dx.doi.org/10.1073/pnas.1203141109.]

Kiff, L.F., Peakall, D.B., and Wilbur, S.R., 1979, Recent 

changes in California condor eggshells: Condor, v. 81, 

no. 2, p. 166–172. [Also available at https://sora.unm.edu/

node/102945.

Koford, C.B., 1953, The California condor: National Audubon 

Society Research Report, no. 4, New York, National Audubon Society, 154 p.

Condor foraging area, Tejon Ranch, Kern County, CA, 1980s. Photo by Noel F.R. Snyder, U.S. Fish and Wildlife Service.
156 The History of Patuxent: America’s Wildlife Research Story

Locke, L.N., Bagley, G.E., Fricke, D.N., and Young, L.T., 

1969, Lead poisoning and aspergillosis in an Andean condor: Journal of the American Veterinary Medical Association, v. 155, no. 7, p. 1052–1056. [Also available at http://

www.cabdirect.org/abstracts/19721300469.html;jsessionid=

4C0E8F4F6FE033F53E11C80F2BAE0E35.]

Mallette, R.D., and Borneman, J.C., 1966, First cooperative 

survey of the California condor: California Fish and Game, 

v. 52, no. 3, p. 185–203.

O’Shea, T.J., Reeves, R.R., and Long, A.K., eds., 1999, 

Marine mammals and persistent ocean contaminants: 

Bethesda, MD, Marine Mammal Commission, Proceedings 

of the Marine Mammal Commission Workshop, Keystone, 

CO, October 12–15, 1998, 150 p. [Also available at http://

www.mmc.gov/wp-content/uploads/contaminantsreport.

pdf.]

Mee, Allan, and Hall, L.S., eds., 2007, California condors in 

the 21st century: Series in Ornithology no. 2, Cambridge, 

MA, and Washington, D.C., Nuttall Ornithological Club and 

American Ornithologists’ Union, 279 p.

Meretsky, V.J., Snyder, N.F.R., Beissinger, S.R., Clendenen, 

D.A., and Wiley, J.W., 2000, Demography of the California 

condor—Implications for reestablishment: Conservation 

Biology, v. 14, p. 957–967. [Also available at http://dx.doi.

org/10.1046/j.1523-1739.2000.99113.x.]

Miller, A.H., McMillan, I., and McMillan, E., 1965, The current status and welfare of the California condor: National 

Audubon Society Research Report, no. 6, 61 p.

Ricklefs, R.E., ed., 1978, Report of the advisory panel on the 

California condor: National Audubon Society Conservation 

Report, no. 6, 27 p.

Rideout, B.A., Stalis, Ilse, Papendick, Rebecca, Pessier, Allan, 

Puschner, Birgit, Finkelstein, M.E., Smith, D.R., Johnson, 

Matthew, Mace, Michael, Stroud, Richard, Brandt, Joseph, 

Burnett, Joe, Parish, Chris, Petterson, Jim, Witte, Carmel, 

Stringfield, Cynthia, Orr, Kathy, Zuba, Jeff, Wallace, Mike, 

and Grantham, Jesse, 2012, Patterns of mortality in freeranging California condors (Gymnogyps californianus): 

Journal of Wildlife Diseases, v. 48, no. 1, p. 95–112. [Also 

available at http://dx.doi.org/10.7589/0090-3558-48.1.95.]

Sibley, F.C., 1968, The life history, ecology and management 

of the California condor (Gymnogyps californianus): Laurel, MD, U.S. Fish and Wildlife Service, Patuxent Wildlife 

Research Center, Annual Progress Report, Project no. B–22, 

34 p.

Snyder, N.F.R., 1983, California condor reproduction, past and 

present, in Temple, S.A., ed., Bird Conservation 1: Madison, WI, University of Wisconsin Press, p. 67–86.

Snyder, N.F.R., 2007, Limiting factors for wild California condors, in Mee, Allan, and Hall, L.S., eds., California condors 

in the 21st century: Series in Ornithology no. 2, Cambridge, 

MA, and Washington, D.C., Nuttall Ornithological Club and 

American Ornithologists’ Union, p. 9–33.

Snyder, N.F.R., and Hamber, J.A., 1985. Replacement-clutching and annual nesting of California condors: Condor, v. 87, 

no. 3, p. 374–378. [Also available at https://sora.unm.edu/

node/103587.]

Snyder, N.F.R., and Johnson, E.V., 1985, Photographic censusing of the 1982–1983 California condor population: Condor, 

v. 87, no. 1, p. 1–13.

Snyder, N.F.R., Johnson, E.V., and Clendenen, D.A., 1987, 

Primary molt of California condors: Condor, v. 89, no. 3, 

p. 468–485. [Also available at https://sora.unm.edu/

node/103834.]

Snyder, N.F.R., and Meretsky, V.J., 2003, California condors 

and DDE—A re-evaluation: Ibis, v. 145, no. 1, p. 136–151. 

[Also available at http://dx.doi.org/10.1046/j.1474-

919X.2003.00132.x.]

Snyder, N.F.R., and Snyder, H.A., 1989, Biology and conservation of the California condor, in Power, D.M., ed., 

Currrent Ornithology, v. 6: New York, Plenum Press, 

p. 175–267.

Snyder, Noel, and Snyder, Helen, 2000, The California condor, 

a saga of natural history and conservation: London, Academic Press, 410 p.

Snyder, N.F.R., and Snyder, H.A., 2005, Introduction to the 

California condor: Berkeley, CA, University of California 

Press, 271 p.

Verner, J., 1978, California condors—Status of the recovery effort: Washington, D.C., U.S. Forest Service, Pacific 

Southwest Forest and Range Experiment Station: Berkeley, 

CA, General Technical Report PSW–28, 30 p. [Also available at http://www.fs.fed.us/psw/publications/documents/

psw_gtr028/psw_gtr028.pdf.]

Walters, J.R., Derrickson, S.R., Fry, D.M., Haig, S.M., 

Marzluff, J.M., and Wunderle, J.M., Jr., 2010, Status of the 

California condor (Gymnogyps californianus) and efforts to 

achieve its recovery: Auk, v. 127, no. 4, p. 969–1001. [Also 

available at http://dx.doi.org/10.1525/auk.2010.127.4.969.]

Wilbur, S.R., 1978, The California condor, 1966–1976—A 

look at its past and future: North American Fauna, v. 72, 

p. 1–136. [Also available at http://dx.doi.org/10.3996/

nafa.72.0001.]

Wilbur, S.R., 2004, Condor tales—What I learned in twelve 

years with the big birds: Gresham, OR, Symbios, 400 p.
Endangered Species Research Program

Endangered Species Research in the Caribbean

James W. Wiley

Although indigenous Amerindian populations adversely 

affected the biota of their island environments, it was not until 

the arrival of Europeans that populations of many plant and 

animal species in the Caribbean Islands declined dramatically (Snyder and others, 1987). Island species are particularly vulnerable to changes in the environment, which, in the 

extreme, can lead to their extinction. The small populations of 

many species that occupy islands have limited gene pools and 

typically show extremes of specialization, characteristics that 

place those species at high risk for decline and extinction with 

rapid environmental change. The most important factor in the 

decline of most Caribbean Island species has been the rapid 

increase in human population and the environmental changes 

related to that growth (Snyder and others, 1987).

Among the islands in the Caribbean, Puerto Rico has 

experienced arguably the most radical transformation of any 

pre-Columbian habitat. Puerto Rico formerly was covered 

in natural vegetation, but by 1912 fewer than 1 percent of 

the original forests were still virgin; all other areas were cut, 

plowed, grazed, burned, or otherwise degraded (Snyder and 

others, 1987). The extensive agriculture supported by Puerto 

Rico’s fertile soils allowed the human population on this 

small (11,489 square kilometers [km2

] [4,436 square miles 

(mi2)]—204 kilometers [km] [127 miles (mi)] east to west 

and 76 km [47 mi] north to south at the widest points) island 

to increase rapidly, to the point that in 2015, with 4 million 

residents (about 350/km2

 [900/mi2]), it was one of the most 

densely populated islands in the world. Although agriculture 

is no longer of major importance in Puerto Rico, the human 

population has continued to grow, causing many plant and 

animal species to decline or disappear from the island (Snyder 

and others, 1987).

The endemic Puerto Rican parrot (Amazona vittata) is 

perhaps the most charismatic and emblematic of the species 

affected by the many environmental problems that have faced 

Puerto Rican wildlife in the past 500 years. Early accounts 

reported the parrot’s presence throughout the island and on 

at least three of Puerto Rico’s four major satellite islands. All 

indications are that the parrot was once abundant on the island, 

perhaps numbering more than 1 million individuals. As Europeans settled the land, parrot populations declined rapidly and 

disappeared from one after another part of the island (Snyder 

and others, 1987).

Development of an Endangered 

Species Research Program in Puerto 

Rico

In 1946, Ventura Barnés, a biologist with the Commonwealth of Puerto Rico Department of Agriculture and 

Commerce, expressed concern over the parrot’s decline 

(Rodríguez-Vidal, 1959). From 1953 through 1956, José 

Rodríguez-Vidal, another Commonwealth biologist, supported by the Pittman-Robertson Program of the U.S. Fish and 

Wildlife Service (USFWS), conducted the first detailed study 

of the parrot. Rodríguez-Vidal found that the parrot population 

in the mid-1950s consisted of only about 200 individuals, and 

those birds were localized in one small area in eastern Puerto 

Rico—the Luquillo Forest (Rodríguez-Vidal, 1959). The evidence of the parrot’s precariously low numbers and restricted 

range prompted further apprehension on the part of Commonwealth Department of Agriculture and Commerce biologists, 

Puerto Rican parrot ready to fledge, 1975. Photo by Jim Wiley, U.S. Fish and 

Wildlife Service.
158 The History of Patuxent: America’s Wildlife Research Story

who attempted to reintroduce the parrot in western Puerto 

Rico, outside its remnant range. Unfortunately, those efforts 

failed. Early studies by Rodríguez-Vidal and others indicated 

that a broad array of environmental problems could have been 

responsible for the parrot’s decline (Snyder and others, 1987).

At the urging of Frank Wadsworth, Director of the 

International Institute of Tropical Forestry (IITF), Río Piedras, Puerto Rico, and with similar efforts by Ray Erickson, 

assistant director in charge of endangered species research at 

Patuxent Wildlife Research Center in Laurel, MD (Patuxent), 

a cooperative program to rescue the parrot was begun in late 

1968. The program was developed as a collaboration of the 

USFWS, U.S. Department of Agriculture, U.S. Forest Service 

(Forest Service), and the government of the Commonwealth of 

Puerto Rico, with support from the World Wildlife Fund. The 

initiation of the Puerto Rican parrot program closely followed 

passage of the Federal Endangered Species Preservation Act 

(1966) and inclusion of the parrot on the Federal Endangered 

Species List in 1967.

At the onset of the Patuxent program in Puerto Rico, all 

participants recognized that the parrot was in steep decline 

and extreme measures would probably be needed to save the 

species. To maximize the likelihood of determining the important factors affecting the parrot population, studies were not 

restricted to the parrot, but included efforts to understand the 

biological characteristics of important natural enemies of this 

species and the biology of other, closely related parrot species 

(Snyder and others, 1987).

History of Patuxent Biologists at the 

Puerto Rico Field Station

Cameron Kepler was the first biologist to lead the Caribbean research program. The Forest Service provided Cam and 

his wife, Angela (“Kay”), with a live-in field station in the 

heart of the parrot’s remnant range in the protected Luquillo 

Forest, to allow them direct, daily access to the remaining 

population. The Keplers conducted research on the parrot and 

other species of conservation concern from 1968 to 1971. 

Cam Kepler’s parrot work focused on determining population size and distribution within the Luquillo Forest, where 

he developed reliable censusing methods (Kepler, 1972b). 

Unfortunately, the accuracy of the counts did not show a 

hoped-for larger population of parrots than had previously 

been reported. Kepler gave special attention to parrots in the 

eastern half of the Luquillo Forest, where he documented daily 

and seasonal foraging behavior and sought to obtain information on recruitment and mortality. Cam left Puerto Rico in 

late 1971 to become Visiting Researcher at the Edward Grey 

Institute of Field Ornithology, Oxford University, after which 

he returned to Patuxent in 1973 to head the whooping crane 

(Grus americana) captive breeding program. He moved on to 

Hawaii to establish the Maui field station in 1977, but returned 

to Patuxent (Southeast Research Station, Athens, GA) in 

1986 to conduct research on Kirtland’s warbler (Seteophaga 

kirtlandii) and other species.

Pico el Yunque, El Yunque National Forest (formerly Luquillo Forest), Puerto Rico, mid-1970s. Photo by Helen Snyder, U.S. Fish and 

Wildlife Service.
Endangered Species Research Program

Endangered Species Research in the Caribbean 159

Cam and Kay Kepler, U.S. Fish and Wildlife Service, at field station, Luquillo 

Forest, Puerto Rico, 1970. Photo by Noel F.R. Snyder, U.S. Fish and Wildlife 

Service.

Noel Snyder was the second scientist to head the Puerto 

Rico field station. Noel and his wife, Helen, conducted 

detailed studies of parrot biology from 1972 through 1976, 

concentrating on the population’s breeding biology. Constant 

daylight observations of all known nests (2–5) were conducted from blinds throughout breeding seasons. The Snyders 

made critical advances in the understanding of the parrot’s 

challenges and, as each bit of knowledge was obtained, 

immediate efforts were made to correct identified problems. 

For the first time, the decline of the parrot population was 

reversed, and the wild population began to increase slowly in 

number. Further, a captive parrot program was established in 

Puerto Rico under the watch of the Snyders, who developed 

fundamental husbandry techniques for captives (Snyder and 

others, 1987).

Jim and Beth Wiley’s work overlapped with that of the 

Snyders; they came to the program as Forest Service employees in 1975, replacing Noel when he transferred to Patuxent in 1976. After a writing stint at Patuxent, Noel headed 

back to the field to study snail kites (Rostrhamus sociabilis) 

in 1978, before leading the California condor (Gymnogyps 

californianus) research program beginning in 1980. Noel left 

the Patuxent program in 1987, when he retired, but continued 

writing scientific papers as a private researcher. The Wileys 

continued the work initiated by the Keplers and Snyders, 

with emphasis on improving reproductive success in the wild 

population and developing techniques for releasing captiveproduced birds into the wild. The aviary flock increased in 

number, produced the first captive-bred Puerto Rican parrots, 

and provided a vital resource for managing the wild flock. 

During this period, the first releases of captive-produced 

parrots were made in the Luquillo Forest, and radiotelemetry 

was used to track post-fledging parrots (Lindsey and Arendt, 

1991). The Wileys left Puerto Rico in late 1986, following 

Noel Snyder to California, where Jim studied the California 

Noel Snyder (left) and John Taapken, U.S. Fish and Wildlife Service, prepare 

for a day in the field, Puerto Rico, mid-1970s. Photo by Helen Snyder, U.S. Fish 

and Wildlife Service.

condor through 1991, when he entered the U.S. Geological 

Survey (USGS) Cooperative Research Units program.

Gerald Lindsey joined the Puerto Rico program in 1985. 

After the Wileys’ departure, he led the program, conducting 

additional work on parrot movements by using telemetry. 

Gerald overlapped with Marcia Wilson, who assumed leadership of the program in 1989, after which time Gerald followed Wiley out to California, where the two worked together 

again—this time on the condor project—before Gerald transferred to Hawaii in 1991.

Marcia Wilson (1989–91) continued to oversee nesting 

investigations, the captive program, and tracking of free-flying 

parrots. In her first year at the station, Marcia was faced with a 

major hurricane, which damaged much of the Luquillo Forest. 

Under the challenging post-hurricane conditions, her team 

documented the greatly reduced population size and distribution of the parrot (Wilson and others, 1994). Marcia left the 

Puerto Rico field station in 1991 to assume an administrative 

post at Patuxent in Maryland.

Wylie Barrow (1990–92) and J. Michael (“Joe”) Meyers (1990–95) joined Marcia in Puerto Rico as Patuxent staff 

members before she went to Laurel. Barrow and Meyers 

continued the telemetry work and developed refined parrotmarking techniques. Meyers was the last of the Patuxent scientists to lead the parrot project, which was abandoned in 1995. 

Barrow and Meyers continued as USGS wildlife research 

biologists—Wylie at the National Wetlands Research Center 

and Joe at Patuxent, stationed at the University of Georgia 

in Athens.

Even before Marcia Wilson left the Puerto Rico field 

station, a transition of agency roles had begun. In 1990, the 

USFWS (Region 4) assumed the lead in management aspects 

of the parrot conservation program, including operation of 

the aviary, in cooperation with the Puerto Rico Department of 

Natural Resources (PRDNR) and the Forest Service. Patuxent 
160 The History of Patuxent: America’s Wildlife Research Story

Puerto Rican field crew at East Fork, Puerto Rico, 1989. Photo by Jim Wiley, U.S. Fish and Wildlife Service.

closed the Puerto Rico field station in 1995. Francisco (“Tito”) 

and Ana Vilella, the first biologists involved in the USFWS 

program (1989–95), were followed by Augustín Valido 

(1991–2001), Fernando Nuñez (2000–06), and Tom White 

(1999–present [2016]), among others.

Challenges and Accomplishments of 

Patuxent’s Program for Conservation of 

the Puerto Rican Parrot

At the outset, Patuxent biologists were faced with a staggering, diverse array of environmental problems affecting the 

parrot (Snyder and others, 1987). Foremost among these was 

the near-complete, island-wide habitat destruction and alteration. Although parrots formerly were found through all of the 

island’s habitats ranging from woodland to forest, the species 

requires habitat that includes trees large enough to harbor 

cavities for nesting. By the mid-1950s, the Luquillo Forest 

was the only location in Puerto Rico that supported a parrot 

population, mainly because it was the only sizable habitat that 

provided nesting cavities. Early studies by Barnés, RodríguezVidal, and others had provided few clues about the parrot’s 

problems (Rodríguez-Vidal, 1959). Rodríguez-Vidal and others suggested that poor nest success, apparently due mainly to 

rat (Rattus rattus) and pearly-eyed thrasher (Margarops fuscatus) predation, was responsible, but a comprehensive appreciation of nesting and other difficulties was still lacking.

Kepler studied three nests from blinds and determined 

that many of the birds in the population were not breeding. He 

also found that the population had declined precipitously since 

the mid-1950s and, with only about 24 wild birds in existence 

in 1968, the species was perilously close to extinction in 

the wild.

Pearly-eyed thrasher—a parrot predator, 

1970s. Photo by John Taapken, U.S. Fish and 

Wildlife Service.

Noel Snyder intensified observations at nests, and initiated comprehensive studies of the ecology of the parrot. 

Through extensive searches and tree climbing, it was determined that although many large trees and cavities existed 

within the protection of the Luquillo Forest, only a few existing cavities were actually suitable for parrot nesting. Many 

of the most amenable cavity-bearing trees had been removed 

through historic logging and timber-stand improvement 

practices in the forest. Further, a tradition of felling nest trees 

or hacking into cavities to harvest chicks for pets selectively 

destroyed the most suitable (that is, parrot-occupied) nesting 

habitat. Snyder’s finding that few good cavities were available for nesting parrots led to an effort to improve existing 
Endangered Species Research Program

Endangered Species Research in the Caribbean 161

suboptimal cavities as well as provide suitable artificial cavities for parrots.

Detailed studies of parrot breeding biology were initiated 

in 1973 with constant daylight observations from blinds of 

as many nests as possible given constraints of personnel and 

their energy limitations. Those were days of pressing urgency, 

as the wild population continued its decline toward extinction 

and the time remaining to find solutions to slow and reverse 

the rapid loss of birds grew increasingly limited. In fact, when 

the low point of only 13 birds known in the wild was reached 

in mid-1975, the goal had to be nothing less than a rapid 

turnaround in the plummeting population to prevent genetic 

collapse of the species. This pressure led scientists to conduct 

intensive trials of innovative methods to protect the parrot and 

reverse the decline in reproductive output.

Intensive observations revealed the relative unimportance 

of some natural and exotic predators, including Puerto Rican 

boa (Epicrates inornatus) and introduced Javan mongoose 

(Herpestes javanicus). Although both are known predators 

of parrots, their role in the decline of the species was evaluated to be less significant than that of other threats. Exotic rats 

and pearly-eyed thrashers were determined to be important 

predators and competitors of the parrot. The now-ubiquitous 

thrasher is evidently a recent invader of the forest and may 

not have threatened historical populations of parrots. Both 

thrashers and rats use tree cavities for nesting, with thrashers 

being particularly aggressive cavity competitors with parrots. Rats were found to be more important as scavengers of 

abandoned parrot eggs or chicks, but nevertheless remained a 

threat to nest contents and were controlled within key nesting 

areas. The thrasher menace was addressed first through direct 

elimination of birds that demonstrated a threat at parrot nests. 

That labor-intensive strategy was not sustainable, however, 

and other control mechanisms were explored. Experimental 

trials using various alternatives of cavity size and dimension 

revealed that thrashers and parrots differed with respect to preferred nest-cavity characteristics, thereby indicating a potential 

option for thrasher management (Snyder and others, 1987). 

Nest boxes of various configurations and sizes were placed 

in the forest and their acceptance by thrashers was monitored 

to determine that species’ preferences. Comparing those data 

with data collected from successful parrot nests revealed that 

parrots preferred deeper cavities than thrashers. A program of 

deepening existing parrot nesting cavities was begun, along 

with provisioning thrashers occupying the parrots’ nesting 

areas with one or more optimal thrasher-sized nest boxes. 

That strategy greatly reduced thrasher-parrot competition and 

resulted in improved parrot nest success.

European honeybee (Apis mellifera), another exotic 

species, also proved to be an important cavity competitor 

with parrots. Honeybees seek cavities with characteristics 

attractive to parrots. Once established in a parrot nest cavity, 

honeybees may occupy that site for years, excluding the parrot 

and further diminishing the overall availability of parrot nest 

sites. Provisioning of additional nearby artificial boxes was 

not feasible in controlling honeybee invasions of parrot nests. 

Fortunately, honeybees typically do not swarm and seek new 

cavities until after the parrot nesting season. A practice of 

physically removing honeybee colonies that invaded parrot 

nests was used successfully for bee control.

Most natural cavities in the Luquillo Forest, where annual 

rainfall averages 500 centimeters (nearly 200 inches), were 

found to have wet bottoms, a characteristic that was determined to lower the chances of parrot egg and chick survival. 

Therefore, in addition to fortifying natural cavities against 

predators and competitors, all existing cavities were modified 

to eliminate problems caused by entry of water.

Although capture of parrots, especially taking young 

from nests, was an important historical factor in the decline 

of the parrot, that practice had declined by the 1960s, in part 

because of greater legal protection of the species and its 

habitat, but also because the pet trade had changed. People 

who wanted pet parrots were more likely to purchase an exotic 

parrot from a pet store than to encounter an individual selling 

Puerto Rican parrots. Unfortunately, this shift from native to 

exotic birds being sought as pets introduced other threats to 

the Puerto Rican parrot. Exotic parrots that escaped or were 

intentionally released from captivity established populations in 

Puerto Rico, and those species threatened the native species as 

competitors for habitat. Even though most alien parrots characteristically remained near populated areas, these established 

exotics posed a far more insidious threat: imported birds might 

carry exotic diseases against which the native parrot likely 

would have no defense.

Harvesting of wild parrots was also deterred by program 

personnel who guarded all active nests throughout the day, 

while watching for signs of other problems that would affect 

nest success and productivity. Although manpower constraints 

did not allow for constant vigil at all nests every day, the number of nests monitored was maximized through the dedication 

of technicians and volunteers. A tabulation of Patuxent parrot 

program activities from 1973 to 1979 showed that scientists 

and assistants had logged more than 20,000 hours of observations from blinds and lookouts.

Radiotelemetry techniques for tracking parrots were 

developed and have proven invaluable in advancing the conservation of the species. In 1985, studies of parrot movements 

using telemetry were brought to the forefront of the research 

program in an effort to determine areas of vulnerability of 

parrots to predation. Telemetry of marked birds confirmed the 

conclusions reached from observations and tallies of parrots: 

post-fledging mortality in the wild flock was high. Known and 

suspected predators included resident red-tailed hawks (Buteo 

jamaicensis), which are found in extraordinarily high densities 

in the Luquillo Forest, and wintering peregrine falcons (Falco 

peregrinus) (Lindsey and others, 1994).

As Patuxent scientists tallied the many environmental 

problems faced by the parrot in the Luquillo Forest, they also 

examined the possibility of establishing flocks in other parts 

of Puerto Rico that might exhibit less challenging environmental conditions than those in the extremely wet rain forest 

at Luquillo and, therefore, might prove to be better suited for 
162 The History of Patuxent: America’s Wildlife Research Story

Gerald Lindsey, U.S. Fish and Wildlife Service, 

tracking parrots with telemetry, Luquillo Forest, 

Puerto Rico, 1986. Photo by Jim Wiley, U.S. Fish 

and Wildlife Service.

Helen Snyder, U.S. Fish and Wildlife Service, 

with Hispaniolan parrots, Sierra de Baharuco, 

Dominican Republic, 1982. Photo by Noel F.R. 

Snyder, U.S. Fish and Wildlife Service.

Beth Wiley, U.S. Fish and Wildlife Service, 

feeding young parrots, Puerto Rican parrot 

aviary, Luquillo Forest, Puerto Rico, 1980s. Photo 

by Jim Wiley, U.S. Fish and Wildlife Service.

self-sustaining populations of the parrot. It became obvious 

that by using current (1985) techniques the parrot population at Luquillo could be sustained only through rigorous and 

extensive management. Although the Luquillo Forest offered 

substantial protection against poaching and habitat alteration, the parrot population there was facing more risk factors 

(especially the wetter environment and denser populations 

of predators and competitors) than existed in other areas in 

Puerto Rico. Several areas that might have been appropriate 

for potential reintroduction areas of the parrot were protected 

as Commonwealth forests and, with a shift of the island’s 

human population away from an agrarian-based society, natural cover, albeit second growth, had increased dramatically to 

about 40 percent of land cover. Patuxent scientists believed it 

would be advantageous to maintain the Luquillo Forest population, which was an important source of behavioral memory, 

while establishing a second free-flying flock distant from the 

Luquillo population and supported by an on-site aviary at a 

second release area. Río Abajo Commonwealth Forest was 

judged to be a suitable site for this next phase of the recovery 

effort on the basis of its recent (1940s) history of parrot presence, habitat recovery, security, and lower densities of predators and competitors.

With intensive and extensive efforts by many dedicated 

people, the Luquillo Forest wild population began a slow 

recovery from the low of 13 individuals and only 2 breeding 

pairs in 1975 (Snyder and others, 1987). By 1989, the wild 

population had reached 47 individuals and as many as 5 (1975, 

1984) breeding pairs in a year. In September 1989, however, 

the first major hurricane in 57 years devastated the Luquillo 

Forest. Despite an apparent loss of more than half the parrots 

in the wild, biologists subsequently located a new nesting area 

that may have been established as a consequence of the storm. 

In fact, an until-then program-high number of breeding pairs 

(six) nested in 1991. By 1995, when Patuxent discontinued 

the parrot program, the wild population had increased to 44 

individuals (Snyder and others, 1987).

Captive Puerto Rican parrots were established at Patuxent in 1970, with two birds donated by the Mayagüez Zoo 

in western Puerto Rico. In early 1972, Paul Sykes (USFWS) 

and Mike Lennartz (Forest Service) were detailed temporarily to Puerto Rico, where they captured two wild birds despite 

tremendous odds and physical challenges. One parrot survived 

and was added to the Patuxent flock. At that time, however, 

an outbreak of Asiatic Newcastle disease in Puerto Rico led to 

rigorous quarantine for any birds entering the United States, 

making it impractical to continue developing the captive flock 

at Patuxent. The quarantine problem and the need to move parrot eggs and chicks to and from wild nests for protection and 

treatment led to the establishment of an aviary in the Luquillo 

Forest in 1973, at which time activities shifted from capture of 

wild, free-flying birds to harvesting eggs and chicks from the 

wild to build the captive flock. In fact, most new members of 

the captive flock were added when eggs or chicks could not 

be maintained safely in the wild because of potentially lethal 

threats to their health and safety. At the onset of developing an 

on-site captive flock, a primary goal was to obtain genetic representation of as many of the existing wild parrots as possible.

With the establishment of the aviary in Puerto Rico, first 

in the Snyders’ living room and later at a dedicated aviary field 

station building, salvaging and manipulation of wild nest contents became practical. Eggs and chicks threatened by problems such as predation, parasitism by warble (Philornis pici) 

and black soldier (Hermetia illucens) flies, or wet cavity floors 
Endangered Species Research Program

Endangered Species Research in the Caribbean 163

could be removed temporarily to the aviary, treated or guarded 

in a safe environment until the threat at the wild nest had been 

addressed, then returned in time to fledge in the wild (Snyder 

and others, 1987). The ability to salvage endangered eggs and 

chicks was further improved through the establishment of an 

on-site captive flock of the closely related Hispaniolan parrot 

(Amazona ventralis). Captive Hispaniolan parrots served as 

surrogates for the endangered species in many ways. During 

periods of high risk at wild Puerto Rican parrot nests, captiveproduced Hispaniolan parrot eggs and chicks were fostered 

into wild nests to replace Puerto Rican parrot eggs and chicks 

until the danger had passed. Hispaniolan parrots were used 

as “guinea pigs” to test for suitability of various procedures 

before they were used on Puerto Rican parrots (Snyder and 

others, 1987). Furthermore, captive Hispaniolan parrots 

proved extremely useful and reliable in incubating eggs and 

brooding of captive- and wild-produced Puerto Rican parrot 

eggs and chicks. In fact, Hispaniolan parrots were far better 

at incubating eggs and brooding chicks than were mechanized incubators and brooders, and required far less intense 

interaction with humans—an important concern for avoiding 

parrot imprinting on humans and reliance on people as sources 

of food.

Although the wild population began to recover from 

its 1975 low, by mid-1979 only 25 or 26 birds were known 

to exist in the wild. The slow recovery made efforts to use 

the captive flock to augment the wild population even more 

important to the parrot’s survival. Efforts to achieve captive 

reproduction involved developing techniques for sexing the 

captives and methods of artificial insemination. Experiments 

in the aviary revealed that replacement clutching was a valuable procedure to increase egg production of parrots; therefore, this practice was incorporated into the captive program 

to boost production. The first captive-bred Puerto Rican parrot 

chick was produced in 1979 and was fostered into an active 

nest, from which it successfully fledged. Thereafter, all fit 

chicks produced through 1986 were fostered into wild nests.

As part of the preparation for releases of free-flying, 

captive-produced Puerto Rican parrots, experimental releases 

of captive-produced Hispaniolan parrots were conducted in 

Half-grown captive Puerto Rican parrot. 

Photo by Jim Wiley, U.S. Fish and Wildlife 

Service.

Mike Lennartz, U.S. Forest Service, carrying Puerto Rican parrots, Luquillo 

Forest, Puerto Rico, 1980s. Photo by Paul Sykes, U.S. Fish and Wildlife Service.

the Dominican Republic in 1982. Those releases of 36 birds 

resulted in an encouraging survival rate of 33 percent, which 

is approximately the rate the program had been able to achieve 

through efforts to manage the wild Puerto Rican parrot flock.

Additional advancements with radiotelemetry and other 

marking techniques gave biologists the confidence to release 

three free-flying, captive-produced Puerto Rican parrots into 

the Luquillo Forest in 1986. That release was preceded by 

aversion conditioning of release candidate parrots by using a 

trained red-tailed hawk. Again, the survival rate was one out 

of three, and, importantly, the surviving individual reached 

sexual maturity and bred in the wild.

After Ray Erickson retired from Patuxent in 1980, the 

program for the conservation of the Puerto Rican parrot was 

managed differently. Field work was delegated primarily 

to technicians and junior scientists, and active nests were 

monitored remotely. Senior scientists devoted more time to 

communicating with their superiors and writing scientifically 

defensible research proposals and manuscripts rather than 

making field observations and guarding nests, a function that 

had proven critical to the recovery effort (Lindsey, 1992). 

Therefore, although the junior scientists and technicians were 

very capable and dedicated to the success of the project, the 

knowledge, experience, and judgment of the senior scientists 

were no longer being applied directly to decision-making in 

the field.
164 The History of Patuxent: America’s Wildlife Research Story

Patuxent administrators continued to work on parrot 

recovery progress after the USFWS and the PRDNR assumed 

expanded roles in the parrot program. The second wild population in Río Abajo, Puerto Rico, was not established in spite 

of strong evidence that the Luquillo Forest environment was 

not optimal for the survival of a viable, self-sustaining wild 

population (Snyder and others, 1987, p. 270). Over time, 

the USFWS strengthened its relations with PRDNR and the 

program’s leadership shifted away from Patuxent. In 1990, 

the Puerto Rican government established and administered a 

second captive breeding site at the Río Abajo aviary in western 

Puerto Rico. Patuxent’s parrot program ended in 1995.

Present Status of the Puerto Rican 

Parrot

The establishment of a disjunct western population of 

Puerto Rican parrots has been of pivotal importance in the 

recovery of the parrot. By 2012, the wild population at Río 

Abajo totaled 40 to 50 birds, after only 6 years of releases. 

Even more encouraging, 10 pairs in the western area were productive in the wild in 2012. The collective captive populations 

in the Luquillo Forest and Río Abajo aviaries, which support 

both of the wild populations, currently (2016) number more 

than 400 birds. A third wild population was established at a 

second western site (Maricao) in Puerto Rico in 2015 (U.S. 

Fish and Wildlife Service, 2016).

Unfortunately, however, after more than 40 years of 

intense efforts to establish a self-sustaining population of parrots in the Luquillo Forest, the flock still struggles to survive, 

with a 2016 wild population of only about 12 birds. If other 

areas of Puerto Rico are included, however, the wild population of the parrot is more than 100 birds (Breining, 2015).

Research on Other Parrot Species and 

Training of Caribbean Conservationists 

and Biologists

Comparative studies of the Puerto Rican parrot and parrot species on other islands were an important component of 

the research conducted by Patuxent biologists. Such studies 

provided insights into some of the ecological and behavioral 

aspects of Puerto Rican parrot biology, particularly when 

“healthy” populations were compared with the small remnant 

population surviving in Puerto Rico. In such comparisons, 

wild populations of Hispaniolan parrots were studied where 

they occurred in large numbers in unaltered ecosystems in 

the Dominican Republic. Among other species studied, to 

varying extents, were Bahama parrot (Amazona leucocephala 

bahamensis) in Great Abaco and Great Inagua Islands (Kepler, 

1982); Grand Cayman (A. l. caymanensis) and Cayman Brac 

(A. l. hesterna) parrots in the Cayman Islands (Wiley, 1991); 

Cuban parrot (A. l. leucocephala) in Cuba and Isla de Pinos 

(now Isla de la Juventud) (Aguilera and others, 1999); blackbilled (A. agilis) and yellow-billed (A. collaria) parrots in 

Jamaica; and St. Vincent parrot (A. guildingii), St. Lucia parrot 

(A. versicolor), and imperial (A. imperialis) and red-necked 

(A. arausiaca) parrots in Dominica (Beissinger and Snyder, 

1992; Snyder and others, 1987). In addition to conducting 

studies of other parrot species and their ecosystems, Patuxent 

scientists trained many resident conservation officers and biologists on site or during their extended stays at the Puerto Rico 

field station. Parrot research and management techniques—for 

example, development of reliable censusing methodology and 

using artificial and improved natural nest structures to augment natural habitat—were transferred to other islands and 

incorporated into those countries’ parrot conservation efforts.

Other Endangered Species Research 

by Patuxent Scientists in the Caribbean

Because of the urgency of reversing the population 

decline of the Puerto Rican parrot, Patuxent biologists focused 

their research on that species; however, many other Caribbean 

wildlife species were in need of conservation efforts. For several species, that need could only be speculated upon, because 

no reliable population numbers or trends were available. 

Island agencies often asked Patuxent scientists to participate in 

studies of species in addition to the parrot. Therefore, Patuxent biologists considered it important to explore the biology 

of other species identified as possibly threatened to provide 

baseline data on those populations as well as a biologically 

sound foundation upon which to base local and international 

conservation efforts.

Seabirds on several of Puerto Rico’s offshore islands and 

cays were the focus of Kepler’s extra-parrot research (Kepler, 

1978). Cam also conducted the first study of Puerto Rican 

nightjar (Caprimulgus noctitherus), a species that was thought 

to have become extinct until its rediscovery in 1961. His work 

and subsequent surveys by other Patuxent biologists produced a basic understanding of the distribution of, status of, 

and threats to the nightjar. In addition, Cam and Kay Kepler 

surprised the ornithological world with their discovery of a 

new species of warbler (the elfin-woods warbler, Setophaga 

angelae) in Puerto Rico in 1970 (Kepler and Parkes, 1972).

Two pigeon species of international concern—plain 

pigeon (Patagioenas inornata) (Wiley and others, 1982) and 

white-crowned pigeon (P. leucocephala) (Wiley and Wiley, 

1979)—were studied by Patuxent personnel. Both suffered 

from the extreme habitat modification seen in Puerto Rico and 

other Caribbean islands. Results of the studies were used by 

the PRDNR to manage the pigeon populations. The formerly 

endangered Puerto Rican plain pigeon (P. i. wetmorei) has 
Endangered Species Research Program

Endangered Species Research in the Caribbean 165

Male white-crowned pigeon brooding, Puerto 

Rico, early 1980s. Photo by Jim Wiley, U.S. Fish 

and Wildlife Service.

shown remarkable recovery since the 1970s, when only about 

120 birds survived, to the several thousand pigeons that are 

currently (2016) spread over a large portion of Puerto Rico.

The endangered yellow-shouldered blackbird (Agelaius 

xanthomus) and several other native host species of a recently 

arrived brood parasite, shiny cowbird (Molothrus bonariensis), 

were the subject of extensive research that improved understanding of the ecological relations between the parasite and 

its hosts (Cruz and others, 1985, 1988; Wiley, 1985, 1988). 

Patuxent scientists and technicians developed techniques for 

controlling the effects of brood parasitism on host species, 

which resulted in improved reproductive success and productivity of hosts, including the yellow-shouldered blackbird 

(Post and Wiley, 1976, 1977; Wiley and others, 1991).

Several endangered or threatened species of raptors were 

the subject of in-depth research by Patuxent biologists. The 

threatened status of endemic races of sharp-shinned (Accipiter 

striatus venator) and broad-winged (Buteo platypterus brunnescens) hawks was determined, and Patuxent scientists initiated 

research on the ecology and behavior of these species. The 

restricted range of the endemic race of short-eared owl (Asio 

flammeus portoricensis) was determined and its status was 

identified as being of national concern.

White-necked crow (Corvus leucognaphalus), endemic to 

Hispaniola and Puerto Rico, was extirpated from Puerto Rico 

in the early 1960s. Patuxent scientists conducted a detailed 

study to determine the possible cause of that extirpation by 

studying populations of the crow in the Dominican Republic 

(Wiley, 2006). That study resulted in a recommendation to 

reintroduce the crow to Puerto Rico as part of a restoration of 

the island’s original ecosystems and a hedge against extirpation in Hispaniola and, thereby, extinction. The data collected 

on the crow in the Dominican Republic serve as a baseline for 

reintroduction into Puerto Rico, although no action to do so 

has been undertaken.

A detailed study of the critically endangered St. Croix 

ground lizard (Ameiva polops) was conducted by Beth and 

Jim Wiley at Green and Protestant Cays at the request of the 

government of the U.S. Virgin Islands. That study provided 

baseline information on the population size, habitat requirements, and management needs of the lizard. The formerly 

endangered Puerto Rican boa (Epicrates inornatus) was the 

subject of a diet study by Jim Wiley (2006).

In addition to studies of threatened wildlife species, 

Patuxent biologists led or were involved in research on several 

nonthreatened species that were important to the understanding of the ecology of the parrot and other species—for 

example, investigations of rat populations in the Luquillo 

Forest, pearly-eyed thrasher ecology and behavior (Snyder and 

Taapken, 1978), and warble and soldier fly biology.

Patuxent scientists served as members or consultants on 

Federal recovery teams for the Puerto Rican parrot, Puerto 

Rican plain pigeon, Puerto Rican nightjar, yellow-shouldered 

blackbird, and several other species in Puerto Rico and 

the U.S. Virgin Islands. The Patuxent scientists’ research 

results provided baseline data critical to the development of 

recovery plans.

Contributions of Patuxent Wildlife 

Research Center to Caribbean 

Conservation Efforts

It may never be known whether the efforts of Patuxent 

scientists and the many other employees and volunteers to 

save the Puerto Rican parrot actually prevented the species’ 

extinction. Certainly their efforts shifted the parrot’s trajectory from a precipitous decline headed for extinction toward 

population growth, albeit slow growth beset by many setbacks 

over the years. Although confidence is not yet warranted, the 

parrot appears to have beaten the odds and recovered from 

an extremely small population consisting of few individuals and, consequently, a dangerously small gene pool. Of 

course, whether genetic problems will appear in the future 

is unknown.

Similarly, it is difficult to evaluate the importance of 

Patuxent’s efforts to save other species from extinction. 

Certainly Patuxent scientists helped to recognize the problems 

faced by several species and to provide population estimates 

upon which the results of future recovery efforts could be 

assayed. Regardless of the effect of Patuxent on the recovery 

of individual species, the program had wide and lasting effects 

on conservation in the region. Importantly, the parrot program 

was one of the first conservation issues to attract the attention 

of the Puerto Rican public and helped to establish a foundation 

for the elevated conservation ethic seen on the island today.

Another of the most important byproducts of the Patuxent 

research program in the region has been the training of several 

conservationists and biologists from other islands while the 

Patuxent scientists were on site or during their extended stays 

in Puerto Rico. Patuxent scientists visited all islands having parrot populations and involved local conservationists in 

research and management efforts. Effective and experimental 
166 The History of Patuxent: America’s Wildlife Research Story

technologies were thereby transferred to other islands and 

incorporated into those countries’ parrot conservation efforts.

The many other people who sacrificed and worked under 

extremely difficult conditions as they participated in parrot recovery efforts also merit acknowledgment. Most were 

employed by the Forest Service, USFWS, and PRDNR, but 

many others generously donated their time as volunteers. 

Advances made through Patuxent and its collaborating agencies would not have been possible without their valuable 

contributions. Equally important as the conservation of individual species and their ecosystems are the effects of Patuxent’s Caribbean program on the professional development 

of the many technicians, assistants, graduate students, and 

volunteers who went on to become influential contributors to 

conservation efforts in Puerto Rico and elsewhere (table 1). In 

fact, several of those program associates have become important decision makers in the parrot’s recovery.

Table 1. Representative technicians, students, and volunteers who participated in Patuxent Wildlife Research Center’s Endangered 

Species Program in the Caribbean, and highlights of their subsequent careers.

[AM, aviary manager; AT, aviary technician; F&AT, field and aviary technician; FT, field technician; GS, graduate student; T, trainee; US, undergraduate student; 

V, volunteer; BBS, North American Breeding Bird Survey; EYNF, El Yunque National Forest; GIS, Geographic Information Specialist; IITF, International Institute of Tropical Forestry; NGO, Nongovernment organization; NMEMNRD, New Mexico Energy, Minerals and Natural Resources Department; PRDNR, Puerto 

Rico Department of Natural Resources; PRP, Puerto Rican parrot; Patuxent, Patuxent Wildlife Research Center; TNWRA, Tennessee Wildlife Resources Agency; 

UPR, University of Puerto Rico; USDA-APHIS, U.S. Department of Agriculture-Animal and Plant Health Inspection Service; USFS, U.S. Department of Agriculture-Forest Service; USFWS, U.S. Fish and Wildlife Service; USGS, U.S. Geological Survey; USNPS, U.S. National Park Service]

Program participant Status in 

program Post-program contributions

Hernán Abreu F&AT Environmental Scientist, USNPS

Wayne Arendt F&AT/GS Wildlife Biologist, IITF

Bonnie Bell F&AT Enforcement Officer, USFWS

Kelly Brock AM/GS Endangered Species Specialist, U.S. Navy

Julio Cardona V Scientist and Director, Puerto Rican conservation NGO

Orlando Carrasquillo F&AT Supervisory Biological Technican, Ecosystem Team, EYNF, USFS

José Colón F&AT Sociedad Ornitología Puertorriqueña, environmental consultant, photographer

Victor Cuevas F&AT Visitor Information Service Leader, EYNF, USFS

Carlos Delannoy F&AT Professor and Department Chair of Biology, UPR-Mayagüez

Linda DeLay V GIS, NMEMNRD

Oscar Díaz-Marrero F&AT Refuge Manager, USFWS

Joe diTomaso F&AT Department Plant Science Chair and Professor, University of California at Davis

Sharon Dougherty V/GS Endangered Species Biologist and cofounder, Circle Mountain Biological Consultants, Inc.

Rosemarie Gnam V/GS Chief, Division Science Authority International Affairs Program, USFWS

Nelson Green T/V Manager, captive parrot program in Dominica

Quammie Greenaway T/V Conservation Officer, Dominica Forestry Department

Robin Knopp F&AT Veterinarian

Ed LaRue F&AT/GS Endangered Species Biologist and Chief Executive Officer, Circle Mountain Biological Consultants, Inc.

Benjamin (“Benji”) Layton F&AT/GS Regional Big Game/Waterfowl Coordinator, TNWRA

Sebastian Lousada V/US Private aviculturalist

Aurea (“Puchi”) Moragón AT Website Manager, EYNF, USFS

Fernando Nuñez F&AT/GS Leader of PRP Recovery Program, USFWS Region 4

Keith Pardieck FT Patuxent BBS Program Coordinator

José Rodríguez AT First comanager. of captive program at Río Abajo aviary, PRDNR

Ann Smith AT First comanager. of captive program at Río Abajo aviary, PRDNR

Dwight Smith F&AT Businessman

John Taapken F&AT Businessman and politician

Monica Tomosy V/GS Chief, U.S. Bird Banding Laboratory; USFS liaison to USGS

Edgar Vazquez Cabrera F&AT Biologist, PRDNR and USDA-APHIS

Michael Zamore T/V Wildlife Research officer, Dominica Forestry Department
Endangered Species Research Program

Endangered Species Research in the Caribbean 167

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Wiley, J.W., 1985a, Bird conservation in the United States 

Caribbean, in Temple, S.A., ed., Bird conservation 2: Madison, WI, University of Wisconsin Press for International 

Council for Bird Preservation, p. 107–159.
Endangered Species Research Program

Endangered Species Research in the Caribbean 169

Wiley, J.W., 1985b, Shiny cowbird parasitism in two 

avian communities in Puerto Rico: Condor, v. 87, no. 2, 

p. 165–176. [Also available at http://sora.unm.edu/

node/103553.]

Wiley, J.W., 1985c, Status and conservation of forest raptors 

in the West Indies, in Newon, I., and Chancellor, R., eds., 

Raptor conservation: International Council for Bird Preservation, Technical Publication no. 5, p. 199–204.

Wiley, J.W., 1985d, The captive programme for the endangered Puerto Rican parrot Amazona vittata: Aviculture 

Magazine, v. 91, no. 2, p. 110–116.

Wiley, J.W., 1985e, The Puerto Rican parrot and competition for its nest sites, in Moors, P.J., ed., Conservation of 

island birds—Case studies for the management of threatened island species: Cambridge, England, International 

Council for Bird Preservation, Technical Publication no. 3, 

p. 213–223.

Wiley, J.W., 1986a, Habitat change and its effects on Puerto 

Rican raptors: International Council for Bird Preservation Birds of Prey Bulletin no. 3, p. 51–56. [Also available 

at http://www.raptors-international.org/book/birds_of_

prey_1986/Wiley_1986_51-56.pdf.]

Wiley, J.W., 1986b, Status and conservation of raptors in 

the West Indies: International Council for Bird Preservation Birds of Prey Bulletin no. 3, p. 57–70. [Also available 

at http://www.raptors-international.org/book/birds_of_

prey_1986/Wiley_1986_57-70.pdf.]

Wiley, J.W., 1988, Host selection by the shiny cowbird: Condor, v. 90, no. 2, p. 289–303. [Also available at http://sora.

unm.edu/node/103956.]

Wiley, J.W., 1991, Status and conservation of parrots and 

parakeets in the Greater Antilles, Bahama Islands, and 

Cayman Islands: Bird Conservation International, v. 1, 

p. 187–214. [Also available at https://doi.org/10.1017/

S0959270900000599.]

Wiley, J.W., 1996, Ornithology in Puerto Rico and the 

Virgin Islands, in Figueroa Colón, J.C., ed., The scientific survey of Puerto Rico and the Virgin Islands—An 

eighty-year reassessment of the islands’ natural history: 

New York, Annals of the New York Academy of Sciences, v. 776, p. 149–179. [Also available at http://dx.doi.

org/10.1111/j.1749-6632.1996.tb17419.x.]

Wiley, J.W., 2003, Habitat association, size, stomach contents, 

and reproductive condition of Puerto Rican boa (Epicrates 

inornatus): Caribbean Journal of Science, v. 39, no. 1, 

p. 189–194.

Wiley, J.W., 2006, The ecology, behavior, and conservation 

of a West Indian corvid, the white-necked crow (Corvus 

leucognaphalus): Ornithología Neotropical, v. 17, no. 2, 

p. 105–146. [Also available at https://sora.unm.edu/

node/119745.]

Wiley, J.W., Cotte, R., Parker, W.T., Raffaele, H.A., Vivaldi, 

J.L., and Snyder, N.F.R., 1982, Puerto Rican plain pigeon 

recovery plan: Atlanta, GA, U.S. Fish and Wildlife Service, 

52 p. [Also available at https://www.fws.gov/caribbean/

PDF/Recovery_Plans/Columba_inornata_wetmorei.pdf.]

Wiley, J.W., and Gee, G., 1981, Using captive propagation 

to help save the Puerto Rican parrot: AFA Watchbird, v. 8, 

no. 5, p. 4–11. [Also available at https://journals.tdl.org/

watchbird/index.php/watchbird/article/view/2037/0.]

Wiley, J.W., Gnam, R.S., Koenig, S.E., Dornelly, A., Gálvez, 

X., Bradley, P.E., White, T., Zamore, M., Reillo, P.R., and 

Anthony, D., 2004, Status and conservation of the family 

Psittacidae in the West Indies: Caribbean Journal of Ornithology, v. 17, p. 94–154.

Wiley, J.W., and Perry, H.R., Jr., 1985, El programa de investigaciones ornitológicas de Patuxent, in Stiles, F.G., and 

Aguilar, P.G., eds., Proceedings I Symposio de Ornitologia 

Neotropical, IX Congreso LatinAmericano de Zoologico, 

14–15 Octobre 1983: Arequipa, Peru, Asociación Peruana 

para Conservación de la Naturaleza, World Wildlife Fund–

U.S. and U.S. Fish and Wildlife Service, 126 p.

Wiley, J.W., Post, William, and Cruz, Alexander, 1991, 

Conservation of the yellow-shouldered blackbird Agelaius 

xanthomus, an endangered West Indian species: Biological 

Conservation, v. 55, no. 2, p. 119–138. [Also available at 

http://dx.doi.org/10.1016/0006-3207(91)90052-B.]

Wiley, J.W., Snyder, N.F.R., and Gnam, R.S., 1992, Reintroduction as a conservation strategy for parrots, in Beissinger, S.R., and Snyder, N.F.R., eds., New World parrots in 

crisis—Solutions from conservation biology: Washington, 

D.C., Smithsonian Institution Press, p. 165–200.

Wiley, J.W., and Wiley, B.N., 1979, The biology of the whitecrowned pigeon: Wildlife Monograph no. 64, 54 p.

Wiley, J.W., and Wunderle, J.M., Jr., 1993, The effects 

of hurricanes on birds, with special reference to Caribbean islands: Bird Conservation International, v. 3, no. 4, 

p. 319–349. [Also available at http://dx.doi.org/10.1017/

S0959270900002598.]

Wilson, K.A., Field, R., and Wilson, M.H., 1995, Successful 

nesting behavior of Puerto Rican parrots: Wilson Bulletin, 

v. 107, no. 3, p. 518–529. [Also available at http://sora.unm.

edu/node/131313.]
170 The History of Patuxent: America’s Wildlife Research Story

Wilson, K.A., Wilson, M.H., and Field, Rebecca, 1997, 

Behavior of Puerto Rican parrots during failed nesting 

attempts: Wilson Bulletin, v. 109, no. 3, p. 490–503. [Also 

available at http://sora.unm.edu/node/131502.]

Wilson, M.H., Kepler, C.B., Snyder, N.F.R., Derrickson, S.R., 

Dein, F.J., Wiley, J.W., Wunderle, J.M., Jr., Lugo, A.E., 

Graham, D.L., and Toone, W.D., 1994, Puerto Rican parrots 

and potential limitations of the metapopulation approach 

to species conservation: Conservation Biology, v. 8, no. 1, 

p. 114–123. [Also available at http://dx.doi.org/10.1046/

j.1523-1739.1994.08010114.x.]

Wunderle, J.M., Jr., Snyder, N.F.R., Muiznieks, Britta, Wiley, 

J.W., and Meyers, J.M., 2003, Histories of Puerto Rican parrot nests in the Caribbean National Forest/Luquillo Experimental Forest, 1973–2000: Portland, OR, U.S. Department 

of Agriculture, Forest Service, International Institute of 

Tropical Forestry, General Technical Report IITF–GTR–21, 

28 p. [Also available at http://www.fs.fed.us/pnw/pubs/iitf/

gtr21.pdf.]
Endangered Species Research Program

A Personal Perspective on Searching for the Ivory-Billed 

Woodpecker: A 41-Year Quest

Paul W. Sykes, Jr.

Introduction

I first learned about the Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, while attending high school in 

the mid-1950s. Patuxent wildlife biologists Brooke Meanley, 

Chandler (Chan) S. Robbins, and Robert (Bob) E. Stewart, Sr., 

visited me at my parents’ home in Norfolk, VA. I was the 

compiler of the Norfolk County Christmas Bird Count (which 

included the eastern portion of the Virginia sector of the Dismal Swamp). As part of that count, we had for several years 

been estimating populations of red-winged blackbirds (Agelaius phoeniceus) and common grackles (Quiscalus quiscula) 

in the millions. Patuxent was beginning studies of blackbird 

depredations on agricultural crops.

Approximately 10 years later, while I was attending 

graduate school at North Carolina State University at Raleigh, 

the chairman of my graduate committee, Thomas L. Quay, 

professor of zoology, suggested that I visit Patuxent to meet 

some of the staff and investigate job opportunities with the 

Bureau of Sport Fisheries and Wildlife (which became the 

U.S. Fish and Wildlife Service) within the U.S. Department of 

the Interior. I made two such trips, and was greatly impressed 

by the caliber of the research being conducted at Patuxent.

Toward the end of my graduate studies during the first 

half of 1967, I applied for a position as a wildlife biologist 

(research) at Patuxent, and, much to my delight, I got the job. 

I was hired on July 7, 1967, by Ray C. Erickson, Assistant 

Director of Patuxent; he was also in charge of the Endangered 

Wildlife Research Program housed at Snowden Hall on the 

Patuxent campus. At that time, Eugene (Dusty) H. Dustman 

was the center director, Pearle Sisler was head of the personnel 

office, and Bertha Preston was the program’s secretary, with 

Barbara Nichols coming on board several years later. Others 

in the program at the time included Glen Smart, Gene Cowan, 

Bruce Williams, James Stephenson, and Wayne Shifflett. 

Wildlife biologists at the field stations included John L. Sincock at Kauai, Winston (Win) E. Banko on the “Big Island” of 

Hawaii, Fred C. Sibley in California, Roy E. Tomlinson in Arizona, and Donald Fortenbery in South Dakota. Bill and Lucille 

Stickel and Brooke Meanley and family lived nearby at Patuxent in a two-story duplex. (In the late 1960s, fellow employees 

were addressed by their first names, from the Bureau director 

down. The agency was like extended family.)

After the departure of Norman Holgerson, my duty 

station was a one-man office in Delray Beach, Palm Beach 

County, FL. This was my first permanent job, and resulted in 

a career that lasted just short of 40 years; I retired on April 3, 

2007. My primary duties were to investigate the distribution, 

population dynamics, and biology of the snail kite (Rostrhamus sociabilis plumbeus) (at that time the common name 

was Everglade kite or Florida Everglade kite), the ivorybilled woodpecker (Campephilus principalis principalis), 

the dusky seaside sparrow (Ammodramus maritimus nigrescens) (formerly considered a full species, unfortunately now 

extinct), and other endangered species in the southeastern 

United States.

The Bureau of Sport Fisheries and Wildlife Research 

project work unit on the ivory-billed woodpecker (IBWO), 

“Status and distribution of the American ivory-billed 

Nestling ivory-billed woodpecker and J.J. Kuhn, local guide, 

in the Singer Tract, LA, March 6, 1938. Photo by James T. 

Tanner, graduate student, Cornell University. Photo coutesy 

of Tensas River National Wildlife Refuge Collection at the 

Louisiana State University Library, Baton Rouge, LA.
172 The History of Patuxent: America’s Wildlife Research Story

woodpecker,” authorized me to work with the species in the 

southeastern United States from October 1, 1967, to October 1, 1970. Given the circumstances, this project became 

open-ended, or, as fellow researcher J. Michael Scott (at the 

Hawaii field station on the “Big Island”) told Ray Erickson at 

one of our Endangered Species Research Program meetings at 

Patuxent, “Thanks for the long leash.”

The information presented here is derived from my 

weekly and monthly activity reports (1967–92), memoranda 

and other correspondence, office files, my field notes, the 

literature, and consultations and work with others. My efforts 

to find the IBWO are described here for the first time, and are 

presented in chronological order. The names of those who 

contributed to my field work are included for the historical 

record. Without the help of these persons and many others, my 

searches would not have been possible.

Searches

On my first attempt to locate an IBWO, I traveled alone 

to the Green Swamp in northern Polk County, FL, on October 

14, 1967. On October 16, I accompanied Richard A. Long 

(wildlife officer, Florida Game and Fresh Water Fish Commission—now the Florida Fish and Wildlife Commission), in an 

open 4x4 Jeep into the Green Swamp along the Withlacoochee 

River in Polk and Sumter Counties. It was on this trip that I 

heard what sounded like a loud white-breasted nuthatch (Sitta 

carolinensis)—like the “kent” calls of an IBWO. I had on 

tape a copy of IBWO vocalizations from the Cornell Lab of 

Ornithology (Ithaca, NY) that Professors Arthur A. Allen and 

Peter Paul Kellogg and doctoral student James T. Tanner had 

recorded at the Singer Tract (an 81,000-acre property named 

after the sewing machine company that owned the land) in 

northeastern Louisiana in the mid-1930s. I had studied this 

tape prior to beginning my search so I could readily recognize 

the vocalizations if I encountered any IBWOs.

When I heard the nuthatch-like vocalizations, the hair 

on the back of my neck stood up and I experienced an intense 

adrenaline rush. Richard quickly stopped the vehicle on the 

bank of the river. I stepped out of the vehicle and looked 

around. The sound originated at the top of a water oak (Quercus nigra)—it was a blue jay (Cyanocitta cristata)! I was both 

surprised and disappointed—but I learned that blue jays can 

produce a very good imitation of an IBWO call and, therefore, 

hearing the bird without seeing it can lead to false reports of 

this woodpecker. From that time to the present (2016), I have 

heard from observers who witnessed blue jays making such 

calls; one report was from New Jersey, far from the IBWO’s 

historic range. Other species, particularly northern flickers 

(Colaptes auratus), also may on occasion mimic an IBWO 

call. Henry M. Stevenson (professor of zoology, Florida 

State University, oral commun., about 1969) told me he had 

witnessed a flicker giving a call that sounded like that of an 

IBWO in either Alabama or northern Florida (I cannot recall 

which). In Louisiana, graduate student Laurence (Laurie) 

J.J. Kuhn, a local guide, and Peter Paul Kellogg, Cornell University, making 

sound recording of ivory-billed woodpecker in the Singer Tract, LA, April 1935. 

Photo by James T. Tanner, Cornell University graduate student. Photo courtesy 

of Tensas River National Wildlife Refuge Collection at the Louisiana State 

University Library, Baton Rouge, LA.

C. Binford (Louisiana State University, oral commun., about 

1969) heard a flicker giving a call that sounded like an IBWO. 

In both cases, the source of the calls was found and the birds’ 

true identities were determined. At the time, neither of these 

gentlemen knew of the other’s observation.

H.V. (Tommy) Hines (pilot and game management 

agent, Bureau of Sport Fisheries and Wildlife) flew me over 

the Green Swamp and along the course of the Withlacoochee 

River on October 17, 1967. No IBWOs were found in the 

swamp on October 14, 16, or 17.

I conducted a search in southwestern Florida on October 31, 1967, with James (Jimmy) Poncier (wildlife officer, 

Florida Game and Fresh Water Fish Commission). We worked 

Bright Hour Ranch, Sour Orange Hammock, Myrtle Slough, 

and Prairie Creek in DeSoto County, and the Sparkman area 

and Babcock Ranch in Charlotte County. In the late afternoon, I flew with John R. Dowd (pilot, Florida Game and 

Fresh Water Fish Commission) for 1.5 hours at low altitude 

(300–400 feet [ft]), making a big loop over the State psychiatric hospital on Florida State Road 70, Sour Orange Hammock, 

Tipper Bay Slough, Telegraph Swamp, Babcock Ranch, Prairie Creek, and Tiger Bay Slough. No IBWOs were detected 

and no sign of their presence was noted.

On November 10, 1967, Henry Stevenson (Florida State 

University) and I searched for IBWOs on the Chipola River 

and at Dead Lake in Gulf and Calhoun Counties in the Florida 

Panhandle. We lost our way on the river for a short time, as 

we returned to the boat landing after dark with no flashlight or 

other light source. We did not observe any IBWOs or see any 

sign of their presence. In 1950, IBWOs were reported in this 

area by ornithologists Whitney Eastman and Muriel Kelso, 

and also by Davis Crompton, a birder from Massachusetts, but 

in that same year James T. Tanner (then professor of zoology, 

University of Tennessee) and Herbert L. Stoddard, Sr. (director 
Endangered Species Research Program

A Personal Perspective on Searching for the Ivory-Billed Woodpecker: A 41-Year Quest 173

and president of Tall Timbers Research Station, Tallahassee, 

FL), searching separately, did not locate the species. However, 

naturalist John V. Dennis reported hearing an IBWO call five 

times in the Chipola River Swamp on April 5, 1951. This 

appears to be the last report of the IBWO in the area (Jackson, 

2004).

On November 12, 1967, Wayne Shifflett (then a refuge 

management trainee at St. Marks National Wildlife Refuge, 

formerly at Patuxent) and I looked for IBWOs along the east 

side of the Apalachicola River, in Tates Hell Swamp, and in 

part of the Apalachicola National Forest in Franklin County, 

FL, with negative results. I spent much of November 13 on 

the east side of the Apalachicola River in Liberty County, also 

with negative results.

I visited Tall Timbers Research Station just north of 

Tallahassee on November 14, 1967, where W. Wilson Baker 

(biologist at the station) introduced me to Herbert Stoddard. 

Stoddard stated that he had seen IBWOs several times, but did 

not divulge dates, locations, or other details of his sightings 

(Herbert Stoddard, Tall Timbers Research Station, oral commun., 1967). I learned later that most of Stoddard’s sightings 

James Tanner near large sweet gum tree in optimum ivory-billed woodpecker 

habitat, Singer Tract, LA, May 1937. Photo by James T. Tanner, Cornell 

University graduate student. Photo courtesy of Tensas River National Wildlife 

Refuge Collection at the Louisiana State University Library, Baton Rouge, LA.

had occurred years earlier when he was much younger. 

Presumably such sightings were in the Panhandle of Florida. I 

never discovered the exact locations of most of them.

My first special assignment away from Patuxent’s Florida 

field station was to verify reports by John Dennis of IBWO 

sightings in what is now the Big Thicket National Preserve of 

eastern Texas. I had first met John in the late 1950s on Martha’s Vineyard, MA, when I was an undergraduate student. At 

that time he was mist-netting (capturing birds with Japanese 

mist nets) and banding landbird migrants as part of “Operation Recovery,” a cooperative study of fall bird migration in 

the eastern United States, mainly along the Atlantic Coast. 

On April 17, 1948, John Dennis and Davis Crompton had 

rediscovered and photographed IBWOs in eastern Cuba after 

the species had not been seen for several years (Dennis, 1948; 

Jackson, 2004). In 1966–68, John was under contract with the 

Bureau of Sport Fisheries and Wildlife to locate IBWOs that 

were being reported by local residents in eastern Texas.

I met Harry Goodwin (Endangered Species Manager, 

U.S. Fish and Wildlife Service [USFWS]) at his office in the 

Main Interior Building in Washington, D.C., on August 9, 

1967. Harry briefed me on the reports that John Dennis had 

been sending him of IBWO sightings, vocalizations, feeding 

signs, etc., in East Texas. Harry needed to know for certain 

if these reports were accurate (at one point Dennis estimated 

5 to 10 pairs). The information Harry presented to me was 

very encouraging.

On the afternoon of August 25, 1967, I was at an IBWO 

meeting at Patuxent that was attended by John Dennis, Ray 

Erickson, and Harry Goodwin, and also Patuxent research 

managers Ralph Andrews and Gene Knoder. At this gathering, 

I obtained more information on contacts and places to search 

in East Texas, coastal South Carolina, Georgia, and Florida. In 

the course of our discussions, Dennis mentioned that because 

beetle infestations in large timber stands might tend to attract 

any IBWO present in an area, it might be worthwhile to 

contact foresters in the southeastern United States for possible leads to the locations of such infestations (John Dennis, 

contractor, U.S. Fish and Wildlife Service, oral commun., 

1967). At the close of the meeting, he gave me several suggestions based on his long experience searching for IBWOs 

that I found helpful during field work in Texas starting in early 

January 1968.

With the information I had been given at this meeting and 

the earlier meeting with Harry Goodwin, I fully expected to 

find an IBWO in the southeastern United States in the coming year. In preparation for the trip to Texas, I invited James 

Tanner to join me in searching for IBWO in Texas, and he 

accepted. Jim (who died in January 1991) was the world’s 

foremost authority on the IBWO and is the only person ever to 

have conducted a formal study of the species in the wild in the 

United States (Tanner, 1942), as part of his doctoral program 

at Cornell University under the direction of Arthur Allen. All 

other investigators, from Mark Catesby in 1731 to recent times 

(Catesby, 1731; Jackson, 2002), have had only brief encounters with IBWOs.
174 The History of Patuxent: America’s Wildlife Research Story

Male ivory-billed woodpecker at nest in red maple tree, Singer Tract, LA, April 

1935. Photo by James T. Tanner, Cornell University graduate student. Photo 

coutesy of Tensas River National Wildlife Refuge Collection at the Louisiana 

State University Library, Baton Rouge, LA.

While en route to East Texas in early January 1968, I 

visited Henry Stevenson at Florida State University; George 

H. Lowery, Jr., and Robert J. Newman (professors of zoology, Museum of Zoology, Louisiana State University, Baton 

Rouge); and Jacob (Jake) M. Valentine (Gulf Coast Wildlife 

Management Biologist, Bureau of Sport Fisheries and Wildlife, Lafayette, LA) to discuss IBWOs and Mississippi sandhill 

cranes (Grus canadensis pulla). Upon reaching Texas, I talked 

with Bureau and State personnel about the IBWO and made 

arrangements to obtain access to boats and to fly over the 

Neches River flood plain. I began field work on January 10 

and continued through January 31, 1968, in the Neches and 

Angelina River bottoms and a section along the Trinity River 

to the west, spending a total of 118 hours in the field. During 

the search, I covered 64 mi on foot, 372 mi by boat, 380 mi by 

airplane, and 2,600 mi in vehicles. Jim Tanner and I searched 

in the field together from January 19 to 27, and the two of us 

spent January 23 in the field with John Dennis. During January 

21–27, Jim Tanner and I were joined in the field by Ernest 

McDaniel. Ernest was a teacher living in Kountze, TX, and 

a past president of the Texas Ornithological Society. He is an 

accomplished birder and woodsman, and knows East Texas 

well, particularly the area north of Dam B Reservoir on the 

Neches River bottoms, where most reported sightings have 

occurred. Ernest had been searching in the Big Thicket region 

for the past 6 years, but had not seen or heard an IBWO. 

During 1966 and 1967, he increased his efforts to find the 

bird. He had been checking woodpecker cavities, finding only 

evidence of the common species of woodpeckers and small 

mammals. (It should be noted that he could free-climb a tree 

like a squirrel.)

The Neches River bottoms are used heavily for outdoor 

recreation and commercial purposes. We interviewed several people who had reported seeing an IBWO. We searched 

carefully (two or more times) on foot in localities where the 

birds had been reported, as well as at other areas that appeared 

promising. Stopping and listening for a period of several minutes at intervals was standard procedure in all field work. The 

search protocol also included looking for feeding signs (bark 

scaling, pits, etc.) and possible nesting/roosting cavities. Tanner (1942) used this technique for locating IBWOs and found 

it to be highly successful.

I did not see or hear any IBWOs or find any tangible 

evidence to confirm their presence in eastern Texas. Reliable observers have not seen IBWOs despite being alert and 

searching for them in the Neches River Basin. We found 

during searching that feeding sign and several roost holes 

believed to be made by IBWOs were actually those of the 

pileated woodpecker (Dryocopus pileatus), a very common 

species in the Big Thicket region.

With most IBWO reports, a bird had either been seen but 

not heard, or heard but not seen. Many reports of IBWOs had 

been accepted without question, leading to the dissemination 

of much erroneous information. Although it cannot be proven 

that IBWOs are not present, it is remotely possible that the 

birds that were reported were merely passing through the area 

where they were seen. The reported sightings of the IBWO 

in eastern Texas appear to be misidentifications, probably of 

pileated woodpeckers. I submitted a 31-page in-house report 

(P.W. Sykes, Jr., U.S. Fish and Wildlife Service, unpub. report, 

1968), which included an appendix of 14 maps (portions of 

U.S. Geological Survey [USGS] topographic quadrangles 

showing the areas visited), documenting my findings to Ray 

Erickson, Harry Goodwin, and John Aldrich (zoologist, 

National Museum of Natural History, Washington, D.C.). On 

my return trip to the field station at Delray Beach, I stopped 

at Louisiana State University and briefly discussed my findings in East Texas with George Lowery and several of his 

graduate students.

George M. Heinzman and H. Norton Agey (Heinzmann 

[sic] and Agey, 1971; Heinzman’s name is misspelled throughout the article), working on surveys for the Florida Audubon 

Society’s Bald Eagle Conservation Project, covered more than 

1 million acres in central Florida, mostly large cattle ranches. 

They had access to most of the private properties, and visited 

them as many as three or four times per year to document the 

status of activity at eagle nests. They reported sightings or 

vocalizations of IBWOs on 11 occasions from 1967 to 1969, 

with no reports in 1965 and 1966. They spent 41 days in the 

area where they reported the presence of IBWOs. I was invited 

to join them in 1968 and was asked not to divulge the search 

location. I honored that request for 43 years but, because no 

IBWOs have been reported from this particular location since 

1969 and all principal parties are deceased, I believe it is now 

time to make the location known. The Heinzman and Agey 
Endangered Species Research Program

A Personal Perspective on Searching for the Ivory-Billed Woodpecker: A 41-Year Quest 175

Pileated

Woodpecker

Male

Pileated

Woodpecker

F emale

Pileated

Woodpecker

F emale

Ivory-billed

Woodpecker

Pileated

Woodpecker

Ivory-billed

Woodpecker

Male

Ivory-billed

Woodpecker

Ivory-billed

Woodpecker Ivory-billed

Woodpecker

Comparison of pileated and ivory-billed woodpeckers showing ventral and dorsal views in flight and perched. From paintings by David Allen Sibley, well-known 

author and bird artist; used with permission.

IBWO reports were at a large cattle ranch with locked gates 

west of U.S. Route 27 in Hardee and Highlands Counties, 

north of Highlands Hammock State Park.

I visited the site with George and Norton on May 18 and 

19, 1968. We did not see or hear any IBWOs. Prior to my 

visit, on January 21, 1968, the duo found a dead sweetgum 

(Liquidambar styraciflua) that exhibited a freshly excavated 

cavity whose entrance hole was 44 ft above ground. On April 

21 they found the tree had fallen and its trunk had broken into 

pieces at the entrance hole. Measurements of the entrance hole 

and cavity were more characteristic of IBWO than of pileated 

woodpecker. Two down feathers were found in the cavity, and 

a white feather was found on the ground beside the entrance 

hole. The feathers were sent to the U.S. National Museum of 

Natural History (a part of the Smithsonian Institution), and the 

white feather was identified by Alexander Wetmore, former 

Secretary of the Smithsonian Institution and world-renowned 

ornithologist, as the innermost secondary feather of an IBWO. 

Dr. Wetmore commented that he could not positively identify 

the down feathers because no IBWO nestling specimens (this 

was prior to widespread use of deoxyribonucleic acid [DNA] 

analysis) were available for comparison (Heinzmann [sic] and 

Agey, 1971). Some years later, Jerome Jackson (Whiteker 

Eminent Scholar in Science at Florida Gulf Coast University, Naples, FL, oral commun., 1994) examined the white 

feather and agreed it was the innermost secondary feather of 

an IBWO. After George Heinzman died, Norton Agey kept 

the tree stub with the cavity for a while, then gave it to Byrum 

(Buck) W. Cooper (a birder and friend of Norton, living in 

Haines City, FL). Buck donated the tree stub to the Florida 

Museum of Natural History. The stub with the cavity (now 

reassembled) and the three feathers are still at the Florida 

Museum of Natural History on the campus of the University of Florida in Gainesville, where I have examined them 

several times.

In an interesting twist to this story, Jerome Jackson, while 

examining IBWO specimens at the Florida Museum of Natural 

History, found the innermost secondary feather missing from a 

female IBWO specimen collected in Florida in 1929. Is this an 

amazing coincidence or was fraudulent activity involved? We 

will probably never know with certainty. I can only say that 

George Heinzman and Norton Agey were friends of mine, and 

I do not believe they would commit such an act.

Heinzman and Agey recorded what they thought were 

vocalizations of an IBWO, but subsequent analysis at the 

Cornell Lab of Ornithology revealed them to be those of a 

pileated woodpecker. Samples from the base of the quill of 

the white secondary feather were sent to two laboratories for 

genetic analysis in 2005 to verify the identification as material 

from an IBWO. The results from the two labs were inconclusive (Andrew [Andy] W. Kratter, Florida Museum of Natural 

History, oral commun., about 2005). In addition to his position 
176 The History of Patuxent: America’s Wildlife Research Story

as Curator of Birds at the Florida Museum of Natural History, 

Andy served on the American Ornithologists’ Union (AOU) 

Committee on Classification and Nomenclature, and formerly 

served on the American Birding Association’s Checklist 

Committee. But, to my knowledge, the feathers have not been 

tested for arsenic or other preservatives that would have been 

used in preparation of a museum specimen to protect it in 

a collection.

I revisited the Green Swamp of Florida on October 1, 

1969, with Gary Hickman (biologist, Bureau River Basins 

Office, Vero Beach, FL; later in his career he was USFWS 

regional director for Alaska, Anchorage). We covered areas 

in the Withlacoochee State Forest from the North, Center, 

and South Grade Roads, and a road extension off the Center 

Grade. On October 2, Gary and I covered areas on the north 

and south sides of the Withlacoochee River in the Green 

Swamp and some private lands along the river. Both days 

produced negative results.

During 1970, reports of IBWO came from South Carolina. From September 12 to 20, 1970, I searched in Scape Oer 

and Black Water Swamps and along the Congaree River with 

Bob and Liz Teulings, Evelyn Dabbs, Eli Parker, and Peggy 

Kilby. Bob Teulings is a coauthor of “Birds of the Carolinas” 

(Potter and others, 1980, 2006); Evelyn Dabbs at the time was 

the President of the Carolina Bird Club; Eli Parker was a local 

birder who claimed to have seen IBWOs in the Scape Oer 

Swamp (Sumter County) in all seasons pre-1970; and Peggy 

Kilby was a local birder. I soon discovered that Eli knew the 

pileated woodpecker quite well. The Teulings and I canoed 

45 mi down the Congaree River starting just south of Columbia on September 15. On September 18, from Santee, the 

Teulings and I canoed 2 mi on the Congaree and 23 mi on the 

Wateree River. Evelyn Dabbs, the Teulings, and I searched a 

swamp area in the central part of the Francis Marion National 

Forest on September 19. The Scape Oer Swamp was searched 

on September 12, 13, 14, 17, and 20. In the course of searching I played a tape of the IBWO vocalizations, but we did not 

see or hear any IBWOs.

At the 1971 AOU meeting in Seattle, WA, Professor 

George Lowery of LSU had two color, slightly out-of-focus 

photographs, apparently taken with an inexpensive camera 

by someone he knew (see Jackson [2004] for details). The 

photos were believed to have been taken within a year or so 

of the meeting. I, along with several others, including Laurence (Laurie) C. Binford (California Academy of Science) 

and Burt L. Monroe, Jr. (professor of biology, University of 

Louisville, later to become chairman of the AOU’s Committee 

on Classification and Nomenclature) were invited to view the 

photos. We went to Dennis R. Paulson’s lab at the University 

of Washington to examine the photos more carefully. The 

images were small, but showed the correct color and markings 

of the IBWO. The bill and eyes were not visible, and we could 

not determine whether, in fact, the image was of a live bird. 

Nearly all those present were skeptical of the authenticity of 

the photos and the photographer. At that time Professor Lowery would not reveal the location where the photos were taken 

or the name of the person who took them. It was surmised by 

those present in Paulson’s lab at the time that the location was 

somewhere in the Atchafalaya River Basin of southern Louisiana. Therefore, during the early 1970s, I acquired a set of 

USGS 7.5-minute quadrangles covering the entire Atchafalaya 

River Basin. I planned to fly over the region, identify the most 

promising areas on the quads, and check them by boat and on 

foot to determine whether IBWOs might still be present. Funding for this proposed project was not forthcoming, however, 

and the plan was abandoned.

From 1973 through 1984, I looked for IBWOs in peninsular Florida, including the Big Cypress area (now Big 

Cypress National Preserve); Fakahatchee Strand (now Fakahatchee Strand Preserve State Park); Ocala National Forest; 

Loxahatchee River; and Highlands Hammock, Myakka River, 

and Tomoka State Parks. I visited some of these areas several 

times without finding any sign of IBWO. From 1985 through 

1999, I did not search for IBWOs, as I had transferred to 

Patuxent’s Athens, GA, field station and was involved with 

other research projects. During this latter period I did not hear 

of any IBWO reports that sounded plausible.

On April 1, 1999 (April Fool’s Day!), while hunting turkeys, David Kulivan, a graduate student at LSU, observed at 

close range what he thought was a pair of IBWOs in the Pearl 

River Wildlife Management Area (WMA). This area is on the 

Mississippi–Louisiana border, on the east side of Interstate 

59 and just north of Slidell, LA. His description of the birds 

was excellent. This sighting was not made public for several weeks. Shortly after the news broke, I was contacted by 

Robert (Bob) P. Russell (biologist, USFWS, Minneapolis–St. 

Paul, MN) about a trip he was planning to search for IBWOs 

in the Pearl River WMA early in 2000, prior to leaf-out. In 

early February 2000, 10 people including Bob and I met at a 

motel in Slidell. For the next 10 days we (I was afield February 5–9) systematically searched for IBWOs in teams of two 

or three, with negative results except for Juliana Simpson (a 

birding friend of Bob Russell), who claimed to have heard and 

glimpsed an IBWO. This report was investigated immediately, 

but no IBWO was found. We concentrated our efforts in and 

around the site where Kulivan reported his sighting. The entire 

WMA is heavily hunted (only squirrel hunting was in season 

during our visit). A team search by the Cornell Lab of Ornithology in early 2002 did not find any IBWOs or any sign that 

they were present.

Several weeks prior to the dramatic public announcement 

of the rediscovery of IBWO by John (Fitz) W. Fitzpatrick 

(Director, Cornell Lab of Ornithology), Scott Simon (Director, Arkansas Chapter of The Nature Conservancy), Gale 

Norton (Secretary of the Interior), and others at Main Interior 

Building, Washington, D.C., on April 28, 2005, I received 

a telephone call from longtime birding friend Carl Perry in 

Pennsylvania that an IBWO had been observed in the Big 

Woods of eastern Arkansas. As all searching in 2004 and early 

2005 had been kept secret, I was awestruck by this news. Carl 

had been tracking reports of IBWO sightings for several years 

and had developed an e-mail and telephone “grapevine” with 
Endangered Species Research Program

A Personal Perspective on Searching for the Ivory-Billed Woodpecker: A 41-Year Quest 177

many people throughout the southeastern United States. For 

details of the event, see Fitzpatrick (2005), Fitzpatrick and 

others (2005), Milius (2005), and Stokstad (2007).

I traveled to eastern Arkansas six times in search of the 

IBWO and looked for possible signs that it might be present. The earlier trips were on my own time and at my own 

expense, as as there was no funded project in place to support 

this work. The first trip was May 5–7, 2005, in the company of 

Steve Holzman (USFWS, Ecological Services, Athens, GA), 

Carl Perry, and Pierre D. Howard (birding friend, attorney, 

and former Lieutenant Governor of Georgia). We searched the 

Bayou de View sector of the Cache River National Wildlife 

Refuge (NWR) and environs, Brinkley, and Prairie Lake of 

the southeastern White River NWR and environs, Dagmar 

WMA, and Rex Hancock Black Swamp WMA. On this trip I 

became interested in woodpecker bill marks that were evident 

from bark scaling, and excavation of pits and furrows. On all 

subsequent trips I measured such bill marks.

On the second trip (June 30–July 2) I was accompanied 

by my wife, Joan. We visited Prairie Lake and Prairie Bayou, 

as well as other sites in the White River NWR. We were 

assisted by Richard E. Hines (refuge biologist), Jamie Kellum (refuge forester), and graduate students T.J. Benson and 

Nick Anich (Arkansas State University). We began to examine 

and measure the bill marks of pileated woodpeckers on trees 

where bark scaling and furrow excavations were present. We 

did this outside Arkansas to compare our observations with the 

features we had found at White River NWR.

On August 11–14, 2005, I visited Arkansas again. I traveled by canoe with M. David Luneau, Jr. (professor of electronics, University of Arkansas at Little Rock), on the Bayou 

de View north of State Route 17 on August 12. On April 25, 

2004, David and his brother-in-law had inadvertently captured 

on video a distant, out-of-focus image of a large black and 

white woodpecker flying from behind the base of a tree. The 

camera was set on automatic and therefore was focused on the 

nearest object(s), which happened to be the handle of a canoe 

paddle and his brother-in-law’s knee; consequently, the background with the bird was out of focus. This is the 4 seconds of 

video analyzed by the Cornell Lab, which concluded that the 

Paul Sykes, U.S. Geological Survey, searching for the ivory-billed woodpecker in Bayou de View, AR, in 2005. Photo by Oron L. (Sonny) Bass, Jr., Everglades 

National Park.
178 The History of Patuxent: America’s Wildlife Research Story

bird was an IBWO. Other locations visited on this trip were in 

the southern part of White River NWR.

Joan and I made a trip to Arkansas during September 

28–31, and were assisted at the Cache River NWR by Ryan 

Mollnow, refuge biologist. We visited the George Tract, 

Biscoe Bottoms Unit, and east side of Bayou de View between 

State Route 17 and Interstate 40. Jacks Bay and Big Island in 

the White River NWR were searched September 30–31.

Carl Perry and I visited eastern Arkansas during January 11–15, 2006. We were joined on this trip by birding 

friends from Macon, GA, Tyrus (Ty) Ivey and Jerry and Marie 

Amerson. During the course of the trip, we visited points 

along Bayou de View, Areas A and B, Stabb Lake in the Cache 

River NWR, the Vera Denning property (we had permission to 

visit this private site), and The Nature Conservancy property at 

an area known as Boom Access. On January 14, I met Martjan 

Lammertink (woodpecker researcher from the Netherlands) 

and his wife Utami (both part of the Cornell search team), 

and we searched in the Boom Access area and examined bill 

marks on many trees, some of which I made impressions of 

using quick-setting mold putty. At this point, not having seen 

or heard an IBWO, I and others began to doubt the reliability 

of the reported sightings on the Bayou de View and in the surrounding areas.

A search was made at the Congaree National Park, SC, 

just south of Columbia, by Steve Holzman and me, together 

with Craig Watson (USFWS, Charleston, SC), Bill Hulslander 

(Park Resources Manager), Laurel Moore Barnhill (biologist, 

South Carolina Department of Natural Resources [now with 

the USFWS at Atlanta, GA]), Stuart Greeter (Realty Division, 

South Carolina Department of Natural Resources [DNR]), 

and birders Sherr Scott and Fran Rametta (South Carolina). 

We covered the elevated loop boardwalk area and the trail 

from Cedar Creek south to the Kingsnake Trail. Steve and I 

measured several large woodpecker bill marks on dead trees 

during the course of the day. No IBWOs were found, but a lot 

of fresh woodpecker feeding sign was noted. Joan and I visited 

the Congaree National Park again in April 2006. We covered 

the area of the boardwalk, but found no sign of the IBWO.

The sixth and final trip to eastern Arkansas was made by 

Steve Holzman and me on February 6–18, 2005, as part of the 

volunteer search team of Cornell Lab of Ornithology at White 

River NWR, with Tom Snetzinger (formerly with USFWS 

in Hawaii), as team leader. Other members of our crew were 

Kenneth (Ken) P. Able (California; retired professor of biology, State University of New York at Albany), Oron (Sonny) 

L. Bass (biologist, Everglades National Park), Keith Brady 

(a birder from Washington State), Walt D. Koenig (researcher, 

Hastings Natural History Reservation, CA, and former editor of “The Condor”), Melinda Welton (birder, Franklin, 

TN), and Larry White (birder, Evergreen, CO). Working in 

pairs, we searched the Prairie Lake area, Scrub Grass Bayou, 

Alligator Lake, Horseshoe Lake, the powerline right-of-way, 

Round Island, Prairie Lake Campground, the Lightbulb area, 

Jacks Bay, the levee south to the confluence of the White and 

Arkansas Rivers, and Dana Rockin. On February 12, Sonny, 

Paul Sykes, U.S. Geological Survey, during ivory-billed woodpecker surveys in 

the Congaree Swamp, SC, 2006. Photo by Joan Sykes, Watkinsville, GA.

Keith, Walt, Steve, and I, in two borrowed canoes, searched 

the Bayou de View from State Route 17 south to the powerline and east to the Vera Denning property, but found no sign 

of IBWOs.

Of interest, during the course of our 2 weeks at White 

River NWR, Sonny Bass discovered an albinistic pileated 

woodpecker that was seen for a period of 3 to 4 days. Several 

others of our group saw it, and the bird was photographed. 

Snyder and others (2009) stated that pileateds occasionally 

exhibit abberant extensive white wing patches closely resembling those of perched ivory-bills. Sometime in the late 1970s, 

Noel Snyder told me of seeing a pileated in south-central 

Florida with many of the secondary feathers being white. 

Therefore, some of the reports of ivory-bills in the southeastern United States could well have been part-albino pileateds.

When it was learned that IBWOs had reportedly been 

seen in the Choctawhatchee River Basin in northwestern 
Endangered Species Research Program

A Personal Perspective on Searching for the Ivory-Billed Woodpecker: A 41-Year Quest 179

Florida in the winters of 2005 and 2006, Sonny Bass, Carl 

Perry, and I visited that area during July 23–28, 2006. Because 

the water level in the swamp was low at the time, we were 

able to cover areas on foot that are flooded in winter. Much 

to our surprise, people were riding jet skis and wave riders up and down the river. We searched Bruce Landing and 

Creek, Roaring Cutoff, the McCaskill Landing area, and boat 

landings on both sides of the river from U.S. Route 90 south 

to Florida State Highway 20 in a canoe borrowed from 

Steve Holzman. The three of us floated 40 mi on the Choctawhatchee River from Morrison Springs County Park south 

to Florida State Highway 20, including Dead River Landing, 

the powerline crossing of the river (both sides), Seven Runs 

Creek, Lost Lake, Little Lost Lake, and Tilley Landing. Most 

of our effort during this trip was concentrated around the powerline crossing, Bruce Creek, and Roaring Cutoff. No sign of 

IBWOs was found, but we did see many pileated woodpeckers, as well as their foraging marks on dead trees.

I visited the Choctawhatchee River on October 27–28, 

2006, with Bob Russell and Gloria Rios (LaFalda, Argentina). 

We met Bobby W. Harrison (assistant professor of communications and arts, Oakwood University, Huntsville, AL) 

on October 26 at Ponce de Leon, FL, where we discussed 

IBWOs (Bobby and Tim W. Gallager, editor of the Cornell 

Lab’s “Living Bird,” and kayaker Gene M. Sparling, local 

guide, had reported seeing an IBWO on the Bayou de View 

on February 27, 2004). Bob, Gloria, and I watched under the 

powerline on the west bank of the Choctawhatchee River and 

searched the Morrison Springs area, Fox Hollow Drive off 

Route 284, Holmes Landing, and Dead River Landing, with 

negative results.

On my third trip to the Choctawhatchee River, Sonny 

Bass and I spent November 7–12, 2006, in the field. The deer 

hunting (gun) season opened during this visit, and the river 

bottom sounded like a shooting gallery. The entire river bottom is heavily hunted for game species; we found expended 

shell casings, camp sites, and trash throughout. We searched 

the west bank of the river at the powerline from U.S. Highway 

90 downstream to Morrison Springs in Sonny’s motorized 

canoe-boat. On foot, we checked the peninsula east of Morrison Springs downstream to Old Creek, covering more of the 

bottomland on foot because the water level was low. We took 

the canoe-boat from Dead River Landing through a series 

of small lakes to the main river course and from McCaskill 

Landing downstream to just north of Roaring Cutoff Island. 

We also hiked around Horseshoe Lake and followed the creek 

northeast to Carlisle Lake, took the canoe-boat from Florida 

State Highway 20 to the river, and traveled downstream 

to East River (which makes a loop off the east side of the 

Choctawhatchee River) and up East River, and checked Tilley 

and Bruce Creek Landings. At 10:05 a.m., we stopped for a 

break on the east side of the Choctawhatchee River about 1 mi 

upstream from the south end of East River. At 10:15 a.m., 

we heard three very loud sounds like an ax hitting a tree with 

great force at an estimated distance of 1,000 ft. We never saw 

what made the sounds, and we are certain no other people 

were in the area. The area is low and not suitable for camping. 

No IBWOs were detected on this trip.

My last trip looking for IBWOs in the western Florida 

Panhandle was from February 20 to March 2, 2007. The river 

level was very high at that time. I searched with Peter Range 

(refuge ranger, USFWS, Savannah River NWR Complex, GA) 

and Steve Calver (biologist, U.S. Army Corps of Engineers, 

Savannah, GA) on the powerline right-of-way on the west side 

of the river, the Bruce Creek area, and Grassey and McCaskill 

Landings; took Peter’s boat upriver from McCaskill Landing 

to the Interstate 10 bridge; and searched Gum Creek Landing, 

the slough in the Oak Creek area, lower Carlisle Creek, Horseshoe Lake, and Cougar Island at Roaring Cutoff. Ken Able 

joined us in the search on February 22. We checked out Cow 

and Cedar Log Landings north of Morrison Springs along 

County Route 181C. We put in at Cedar Log Landing, paddled 

upstream about 1.5 mi, and stopped on the east bank to listen. 

At about 5:00 p.m., Peter reported he heard what sounded like 

kent calls in a series, but what actually made the calls was not 

seen. Steve and I heard nothing. Ken had gone by kayak to 

Lost Lakes. On February 25, birding friends Harry Armistead 

(Philadelphia, PA), Bob Ake (professor of chemistry, Old 

Dominion University, Norfolk, VA), and four others arrived 

to search for the woodpecker. On February 26, Peter, Steve, 

and I put the boat in at Cedar Log Landing and checked areas 

along the east side of the river opposite Old Creek, as well as 

the powerline right-of-way on the west side of the river. The 

next day we observed and listened at Horseshoe Lake; while 

we were there, John Puschock (professional bird guide, and 

owner and operator of Zugunruhe Birding Tours in Seattle, 

WA) came by in his kayak and stopped to discuss the IBWO 

situation. John had not seen or heard an IBWO since he started 

searching the Choctawhatchee River in early January 2007. 

John later told me he did not believe there were any IWBOs in 

the region.

During the last 5 days of this trip we spent a lot of time 

looking and listening on the west bank of the river at the 

powerline. This site is at a bend of the river. It provides a 

0.5-mi view up and down the river and more than a 1-mi view 

across the swamp forest to the east, all the way to the upland. 

On February 28, in addition to the powerline area, Ken and 

I checked Tilley and Dead Lake Landings. At the latter, we 

spoke with Bobby Harrison and others. On March 1, Carl 

Perry joined Ken Able and me at the powerline on the east side 

of the river on the edge of the upland. We had permission to 

cross private land to reach this site. Many pileated woodpeckers are found in this area, as well as other places throughout 

the Choctawhatchee River bottoms. Also on March 1, Ken and 

I checked the boat landings south of Florida State Highway 20, 

including Bozman, Simpler’s, and Rooks fish camps, Smoke 

House Lake, and Magnolia Landing. On March 2, my final 

day, Carl, Ken, and I watched and listened at the powerline. 

On this trip, no one in our group or whom we met in the area 

had ever observed an IBWO on the Choctawhatchee River.
180 The History of Patuxent: America’s Wildlife Research Story

Discussion

During the span of our searches for the IBWO in eastern Arkansas and northwestern Florida, the widths of bill 

marks made by foraging large woodpeckers on dead or dying 

trees were measured in these two states as well as Georgia, 

Maryland, Mississippi, North and South Carolina, Tennessee, 

and Virginia. These marks were measured on 19 species of 

hardwoods. The bill tips of 182 pileated and 178 ivory-billed 

woodpeckers were measured and the shape of bill tips noted 

at 15 museum collections. Posters illustrating measurements 

of the bill marks and bill tips of the two species have been 

presented at meetings at Patuxent (2005), AOU (University 

of California, Santa Barbara, 2005), Georgia Ornithological 

Society (Jekyll Island, GA, 2005), and at a Special Symposium—The Ecology of Large Woodpeckers: History, Status, 

and Conservation (Brinkley, AR, 2005).

Four cavities reported to be those of the IBWO are 

known to be extant in curated collections that my wife, Joan, 

and I examined. There is one such cavity at each of the following institutions: Museum of Comparative Zoology, Harvard 

University, Cambridge, MA; Cornell Lab of Ornithology, 

Ithaca, NY; Florida Museum of Natural History, University 

of Florida, Gainesville; and Anniston Museum of Natural 

History, Anniston, AL. The cavity at Cornell is the nest that 

Arthur A. Allen, Peter Paul Kellogg, and James T. Tanner studied in the Singer Tract in Louisiana in the mid-1930s. Their 

photographs of this nest, including the one on page 174 showing a male IBWO, were widely published.

After conducting several double-blind tests measuring 

the widths of bill marks made by large woodpeckers in bark 

scaling, excavation of nesting/roosting cavities, pits, and furrows on trees and examining the data, Steve Holzman and I 

found that the idea one might be able to determine whether 

such marks were made by either a pileated or an ivory-billed 

woodpecker was not possible as originally had been thought. 

There was too much variability in taking repeated measurements of the same bill mark by the same person or between 

different persons to be able to distinguish between the two 

species. There was also too much variability within marks 

made between individuals of the same species to be useful. 

Bill-mark widths also varied between tree species and state 

of tree decay, and there was a lot of variation in the shape and 

depth of the bill tips of specimens in museum collections both 

within and between the two species. So much for “pipe dreaming”—we had no smoking gun.

Through Judd A. Howell (director of Patuxent at the 

time), funding during the latter part of this project was made 

possible from the center’s discretionary fund. Post-early 1970s 

and prior to funding, all searching was on my own time and at 

my own expense.

The history of the IBWO is well summarized by Jerry 

Jackson (2004) and Noel Snyder and others (2009). The 

David Luneau video, presented as proof of the existence of the 

IBWO in eastern Arkansas by John Fitzpatrick and associates in “Science” (Fitzpatrick and others, 2005, 2006), has 

been questioned by other investigators (Jackson, 2006; Jones 

and others, 2007; Sibley and others, 2006). I viewed David 

Luneau’s 4-second clip three or four times. In my opinion, 

because the image is out of focus (when the original, small 

image was enlarged, it became pixelated), too little of the bird 

is visible, and the lighting is insufficient, the bird cannot be 

identified with any confidence.

My searches for the IBWO began in 1967 and continued 

intermittently through 2007. This effort has taken me to Florida, South Carolina, Louisiana, Texas, and Arkansas. Given 

the information contained in several reports from Florida, 

Texas, and Arkansas, I was certain I would see a living IBWO 

on at least four or five occasions, but it did not happen—I have 

never seen or heard the species in the wild, but have examined 

many study skins and mounts, and have listened to recordings of its vocalizations and double knocks made by Arthur A. 

Allen, Peter Paul Kellogg, and James T. Tanner.

It is impossible to say when the last living IBWO was 

seen in the United States. Although there are many reports 

of sightings over the past 70 years, there is no undisputed, 

verifiable proof of the bird’s existence since the early 1940s. 

Invariably, whenever an IBWO sighting is in the news, there is 

a sharp spike in the number of sightings reported; the reports 

usually cease after a year or two. It is most unfortunate that 

so little effort to save the species was undertaken from the 

mid-1930s through at least the 1970s. Although it is obvious that the IBWO lost most of its habitat in the southeastern 

United States, I came to the conclusion many years ago that 

shooting of the birds for any number of reasons may have 

been the cause of its final demise. Noel Snyder (formerly with 

Patuxent conducting research on the California condor [Gymnogyps californianus] and snail kite) and associates came to a 

similar conclusion (Snyder and others, 2009), and they discuss 

the matter in detail.

James T. Tanner (1942; University of Tennessee, oral 

commun., 1968) and others that preceded him typically 

located IBWOs first by their calls or double knocks or raps, 

then followed the sounds to see the bird(s). In most of the 

reports made in the last several decades, the bird was either 

heard but not seen, or seen but not heard. These reports are 

contrary to accepted knowledge about how to locate the species. Furthermore, most observers saw only a fleeting glimpse 

of a large black and white bird flying away, did not have time 

to use binoculars or take a picture, typically observed under 

poor lighting conditions, had a view obstructed by vegetation 

or other objects, were searching alone, and so on.

Although several plausible sightings of IBWOs have 

been reported, it is puzzling to me why, if the bird still exists, 

no good-quality photos (film or digital) or video has been 

forthcoming. Likewise, all audio recordings of calls and 

double knocks have been of only common species or sounds 
Endangered Species Research Program

A Personal Perspective on Searching for the Ivory-Billed Woodpecker: A 41-Year Quest 181

resulting from nonliving events (gunshots), or were inconclusive with respect to the origin of the sound. I am unaware of 

any animal on the planet as large as the IBWO, living and flying about in habitat surrounded by a sea of humanity, that can 

escape detection, especially given the great effort expended in 

eastern Arkansas and northwestern Florida during 2004–06. It 

is also troubling to me that the bird repeatedly “is seen” and 

then cannot be refound. My long field experience over much 

of North America during the past 66 years tells me that something is amiss.

After the April 28, 2005, announcement about the rediscovery of the IBWO in the Big Woods of eastern Arkansas, 

and given the prestige of the agencies, institutions, organizations, and esteemed individuals involved, it is my opinion that 

most (perhaps as many as 95 to 99 percent) of the people who 

started searching for the bird believed that it was still alive and 

present in the area. I was in this camp for a while. Therefore, 

many searchers may have been subconsciously biased and, 

as a result, not sufficiently cautious in their identifications 

under field conditions. In other words, their perception was 

in error—and they did not actually see what they believed 

they saw. Field experience and skill levels with respect to bird 

identification also affect the accuracy of the identifications, 

particularly when species that are rare in a given area or species believed to be extinct or near extinct in a given area are 

found. Those who have extensive field experience with birds 

know that bird identification requires checking as many field 

marks as possible and repeating this process several times 

while viewing the bird. A brief glimpse or an otherwise poor 

view can result in misidentification. All birders make identification mistakes sooner or later; the point is to be as careful 

as possible in all identifications. In the words of English poet 

Alexander Pope, “To err is human...” On any bird search, 

enthusiasm and expectation can rule the day. The high degree 

of anticipation and excitement inherent in this modern-day 

hunt can sometimes override caution, which may be problematic in the search of the elusive ivory-billed woodpecker.

Acknowledgments

This project could not have been carried out without the 

splendid assistance, cooperation, understanding, and support of friends, associates, and colleagues. I thank you all. In 

particular, I wish to thank Ken Able (State University of New 

York at Albany, retired); Sonny Bass (Everglades National 

Park, FL, retired); Steve Calver (U.S. Army Corps of Engineers, Savannah, GA, retired); Ray Erickson (U.S. Geological 

Survey [USGS] Patuxent Wildlife Research Center [Patuxent], Laurel, MD, retired; Andy Kratter (Florida Museum of 

Natural History, Gainesville, FL); Richard Hines (White River 

National Wildlife Refuge, AR); Steve Holzman (U.S. Fish 

and Wildlife Service [USFWS], Atlanta, GA); Judd A. Howell 

(USGS Patuxent, Laurel, MD, retired); Bonnie Kepler (USGS 

Patuxent, Athens, GA); Cameron Kepler (USGS Patuxent, 

Athens, GA, retired); Brooke Meanley (USGS Patuxent, Laurel, MD); Carl Perry (Armstrong World Industries, Lancaster, 

PA); Matthew Perry (USGS Patuxent, Laurel, MD, retired); 

Tom Quay (North Carolina State University, Raleigh); Peter 

Range (USFWS, Savannah River National Wildlife Refuge 

complex, GA-SC, retired); Bob Russell (USFWS, Minneapolis-St. Paul, WI); Henry Stevenson (Florida State University, 

Tallahassee); my wife, Joan Sykes; and Jim Tanner (University 

of Tennessee, Knoxville). I thank David Allen Sibley (author 

and bird artist, Concord, MA) for permission to use his very 

fine images of pileated and ivory-billed woodpeckers in 

this chapter.

References Cited

Catesby, Mark, 1731, Natural history of Carolina, Florida and 

the Bahama Islands: London, Benjamin White, v. 1, p. 16.

Dennis, J.V., 1948, A last remnant of ivory-billed woodpecker 

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Endangered Species Research Program

Endangered Species Research in Hawaii: 

The Early Years (1965–87)

J. Michael Scott and Cameron B. Kepler

Hawaii is an ecologically isolated archipelago 

2,500 miles from the nearest continent. Its isolation resulted in 

a taxonomically unbalanced flora and fauna with remarkable 

examples of adaptive radiation among those groups of organisms that won the dispersal sweepstakes. It was one of the 

last oceanic island groups to be populated by humans, about 

900 A.D. by Polynesian travelers and in 1778 by Europeans. 

Relatively recent colonization by humans did not save it, however, from the biodiversity losses suffered by other isolated 

archipelagos—it only delayed them (Scott and others, 1988; 

Pratt and others, 2009a).

The size of those losses and the severity of the threats 

were formally recognized by the United States in 1964 with 

the publication of “Rare and Endangered Fish and Wildlife 

of the United States” by the U.S. Department of the Interior 

(DOI) Committee on Rare and Endangered Wildlife Species 

(U.S. Department of the Interior, 1964). Sixteen of the 62 

species in that book, vertebrates all, were Hawaiian. That “red 

book” provided information that was used to compile the first 

formal list of endangered species under the 1966 Endangered 

Species Preservation Act, commonly referred to as “the Class 

of 67” (Wilcove and McMillan, 2006). That first list reinforced the findings of the Committee on Rare and Endangered 

Wildlife Species that Hawaii was home to some of the most 

highly endangered species in the United States. Twenty of the 

first 78 species listed under the Preservation Act (25.6 percent) 

were from Hawaii.

Dr. Ray Erickson was well aware of the challenges the 

country faced in recovering endangered species. A biologist 

in the Division of Research of the Bureau of Sport Fisheries 

and Wildlife in Washington, D.C., Dr. Erikson was a member 

of the Committee on Rare and Endangered Wildlife Species. Beginning in 1956, he had been advocating for funding 

to rear one of America’s rarest birds, the whooping crane 

(Grus americana), in captivity and to conduct research on the 

sandhill crane (Grus canadensis) as its surrogate species. In 

early 1961, responding to a White House call for new ideas 

from Federal employees, Ray offered a proposal for a captive 

propagation and research program on rare and endangered 

species. Although small amounts of funding were received 

as early as that year to construct pens for sandhill cranes and 

support studies of their behavior in Colorado, funds sufficient 

to initiate a multispecies field and laboratory program to study 

rare and endangered species were not available until March 

1966, when the Bureau signed off on $350,000 to support 

endangered wildlife research. With those funds, the research 

and captive propagation effort was moved to Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, from Monte 

Vista National Wildlife Refuge, Alamosa, CO, and Ray was 

placed in charge of what came to be known as the Endangered 

Wildlife Research Program. The original focus on captive 

rearing of whooping cranes and their surrogate the sandhill 

crane continued, but these efforts were quickly expanded to 

include other imperiled species and their surrogates, including black-footed ferret (Mustela nigripes), California condor 

(Gymnogyps californianus), Puerto Rican parrot (Amazona vittata), masked bobwhite quail (Colinus virginianus ridgwayi), 

and Aleutian Canada goose (Branta canadensis leucopareia) 

(U.S. Fish and Wildlife Service, 1976a, b; 1977). Ray Erickson originally envisioned an Endangered Wildlife Research 

Program that would include a field research component involving 10 field biologists that would complement the laboratory 

studies and captive propagation efforts at Patuxent. Four field 

biologists were eventually assigned to Hawaii. The first of 

these was Winston (Win) Banko. His task, as it was for all of 

us, was broad—work on the endangered birds of Hawaii. He 

arrived on Oahu in 1966, but later moved to the “Big Island” 

of Hawaii. John Sincock, who was assigned to Kauai, joined 

him in the islands in 1967. In 1974, Mike Scott joined Win 

Banko on the island of Hawaii, and, in 1977, Cam Kepler was 

assigned to Maui.

That first cohort of Patuxent’s endangered species biologists in Hawaii, Banko, Kepler, Scott, and Sincock, conducted 

extensive studies on the endangered flora and fauna of the 

islands (see Selected References). Their studies involved 

reviews of the literature and museum collections to determine 

the extent of studies conducted and the historical distribution 

of each species, their status and distribution in the field (Scott 

and others, 1977), their natural history and ecology threats, and 

recovery planning. Simultaneously, they were developing the 

methods needed to accurately identify and rigorously assess 

the distribution and abundance of Hawaii’s threatened and 

endangered species under the difficult conditions of complex 

terrain, adverse weather, and extremely low bird densities.
184 The History of Patuxent: America’s Wildlife Research Story

John Sincock, U.S. Fish and Wildlife Service, 

after surveying a Kau transect on Hawaii, 

summer 1976. Photo by U.S. Fish and Wildlife 

Service.

Jim Jacobi and Mike Scott, U.S. Fish and 

Wildlife Service, in Hawaii on the Kona side 

transect, summer 1978. Photo by U.S. Fish and 

Wildlife Service.

John Sincock, U.S. Fish and Wildlife Service, 

waiting for helicopter in Alaka’i Swamp, Kauai, 

1983. Photo by Paul W. Sykes, Jr., U.S. Fish and 

Wildlife Service.

Several books that provide a synthesis of these and other 

efforts to save Hawaii’s endangered avifauna and document 

the methods developed to survey and analyze the information from field studies emerged from the work of Patuxent’s 

biologists and others in the islands. These included Ralph and 

Scott (1981), Scott and others (1986), Scott and others (1993), 

Scott and others (2002), Stone and Scott (1985), and Stone 

and Stone (1989). The importance of collaborations with other 

researchers from Federal and State agencies, nongovernmental 

organizations, and academia as well as the private landowners 

of Hawaii to the success of these efforts cannot be overstated. 

The list of those who worked with us in the field, helped with 

funding, and collaborated on almost every one of the publications that resulted from the U.S. Fish and Wildlife Service 

(USFWS) effort in the islands is long. One need only consider 

the institutional affiliations of the authors of the reports, journal articles, and books we wrote or edited and the individuals 

we recognized in the acknowledgments sections of each publication to gain an appreciation of the truly interdisciplinary and 

interinstitutional nature of our work in the islands.

The arrival of the first Patuxent researchers followed 

shortly after the arrival of Gene Kridler on Oahu in 1965. As 

the first DOI biologist and manager assigned to Hawaii, Gene 

played a key role in identifying research needs and obtaining funds to conduct the needed research. The late 1960s and 

early 1970s saw a great increase in research on the Hawaiian 

biota. Andrew Berger (ornithologist, American Museum of 

Natural History, New York) and his students at the University of Hawaii, other academic researchers, and folks at the 

Hawaii Department of Forestry and Wildlife (HDFW) were 

conducting life-history studies on many of the endemic birds 

(Berger and others, 1969; Engilis and Pratt, 1993; Frings, 

1969; Shallenberger, 1977; Shallenberger and Vaughn, 1978; 

Swedberg, 1967). In 1970, the International Biological Program (Mueller-Dombois and others, 1981) initiated studies on 

island ecosystems and their biological organization. Finally, 

the U.S. Forest Service initiated studies on feather molting 

and behavior of Hawaiian birds (Ralph and Fancy, 1994) 

and the influence of nonnative species on native ecosystems 

(Scowcroft and Giffin, 1983). The role of Patuxent’s four 

research biologists, working along with others, in that resurgence of interest in Hawaii’s endangered biota is documented 

in the narrative that follows.

Win Banko came to the islands in 1966 and spent his first 

year on Oahu. He relocated to the island of Hawaii, where 

he established the Kilauea field station, a year later. Upon 

finding that little field work had been conducted on birds in 

Hawaii since the early 1900s (for example, Baldwin, 1945, 

1947, 1953; Warner, 1960, 1967, 1968), Banko determined 

that his contribution to understanding the endangered species 

of Hawaii would be in examining the literature, long-forgotten 

field notes, and museum specimens to determine what information was already known and where the gaps in our knowledge lay. Early on, however, Win went into the field to survey 

the birds of Kipahulu Valley, Maui, where, as a member of 

The Nature Conservancy’s Kipahulu expedition led by Rick 

Warner, he rediscovered the Maui nukupuu (Hemignathus 

lucidus affinis) (Warner, 1967; Banko, 1968). Banko also 

detected populations of several endangered forest bird species 

near Hawaii Volcanoes National Park. This discovery led to 

the selection of this area for intensive ecological studies by 

scientists associated with the International Biological Program 

and the U.S. Forest Service (Mueller-Dombois and others, 

1981; Ralph and Fancy, 1994).

The bibliography on Hawaiian birds and the documentation and Banko’s summaries of 20,700 status and distribution 

records were published by the Hawaii Cooperative Ecosystems Study Unit as part of its special reports series from 

1980 to 1990. In addition to his library work, Win conducted 

field studies of Hawaiian crows (Corvus hawaiiensis) on 

the leeward side of Hawaii and searched for the endangered 

Hawaiian dark-rumped petrel (Pterodroma sandwichensis) and 

other seabirds high on the desolate volcanic slopes of Mauna 

Kea and Mauna Loa (Banko, 1980). His studies of the crow 

documented its precarious status and prompted the decision to 

bring the first Hawaiian crows into captivity for propagation. 

Those birds were housed in flight cages at Hawaii Volcanoes 

National Park for a short period, then transferred to State 
Endangered Species Research Program

Endangered Species Research in Hawaii: The Early Years (1965–87) 185

managers and used to form the nucleus of the Hawaiian crow 

captive propagation effort (National Research Council, 1992). 

Win retired from the USFWS in 1977.

Soon after his arrival in the islands in 1967, John Sincock conducted wetland surveys to identify possible sites for 

new wildlife refuges. John also initiated the first statistically 

rigorous inventories of endangered birds in the forested areas 

of Kauai (Sincock and others, 1984; Scott and others, 1986) 

and of the endangered birds of the Leeward Islands (Laysan, Midway, and Nihoa): Laysan finch (Telospiza cantans), 

Nihoa millerbird (Acrocephalus familiaris kingi), Nihoa finch 

(Telospiza ultima), and Laysan duck (Anas laysanensis). 

The Leeward Islands transects he established for the land 

bird inventories have been surveyed for more than 40 years 

(Conant and Morin, 2002; Morin and Conant, 1997). The 

wetland surveys of Kauai, conducted collaboratively by John 

with refuge manager Gene Kridler, provided the information needed to establish Hanalei, Huleia, and Kilauea Point 

National Wildlife Refuges and complemented the statewide 

waterfowl surveys by the HDFW (Engilis and Pratt, 1993). 

John expanded his research efforts to include natural history 

studies and threats to survival of three seabirds: Newell’s 

shearwater (Puffinus newelli), band-rumped storm petrels 

(Oceanodroma castro), and Hawaiian dark-rumped petrels. 

After documenting the rediscovery of nesting areas for Newell’s shearwaters (Sincock and Swedberg, 1969), he translocated eggs of this species under nesting wedge-tailed shearwaters (Puffinus pacificus) to secure low-elevation nesting 

areas at the then Kilauea Point National Administrative site 

(Byrd and others, 1984). Presumed offspring resulting from 

those efforts or their young still continue to nest on what is 

now Kilauea National Wildlife Refuge (http://www.fws.gov/

endangered/news/bulletin-spring2009/shearwaters-of-kilaueapoint.html).

Recognizing the heavy mortality suffered by Newell’s 

shearwaters and Hawaiian dark-rumped and band-rumped 

storm petrels from crashing into the ground and other obstacles as a consequence of light pollution, John worked with 

Tom Telfer (HDFW) and researchers at the University of 

Wisconsin to develop methods to reduce light pollution by 

switching and shielding light sources (Reed and others, 1985; 

Telfer and others, 1987).

Left to right: Dave Marshall, Gene Kridler, and Win Banko, U.S. Fish and Wildlife Service, in Alaka’i Swamp, Kauai, HI, 1966. Photo by U.S. Fish and 

Wildlife Service.
186 The History of Patuxent: America’s Wildlife Research Story

Sincock and Tom Telfer established the Save Our Shearwaters (SOS) program in the 1970s. This project involved 

informing the island community of the consequences of the 

annual “raining of shearwaters” and its causes, and rescuing 

and then releasing stranded birds. Like almost every one of the 

Patuxent research studies, it quickly became a family affair 

when John’s wife, Renate, took on many of the day-to-day 

activities of this effort—helping to enlist volunteers in the 

rescue effort, picking up birds, coordinating volunteers, and 

housing and releasing birds. The SOS program continues to 

this day (2016) under the auspices of the Kauai Humane Society (http://kauaihumane.org/services/saveourshearwaters).

John was the first to propose and then conduct an assisted 

colonization for the Northwest Islands passerines. Working with folks in the HDFW and with Gene Kridler of the 

USFWS, he successfully translocated Laysan finches to Pearl 

and Hermes Reefs. However, their efforts to translocate Nihoa 

finches to French Frigate Shoals were unsuccessful (Conant 

and Morin, 2002). One product of John’s efforts in the Leeward Islands was a conservation plan for the future protection 

of the islands’ endemic avifauna (Sincock and Kridler, 1977). 

John was the last of the original cohort of Patuxent research 

biologists to leave Hawaii. He left the islands and the USFWS 

in 1988.

Mike Scott arrived fresh from graduate school in the 

fall of 1974 to work with the endangered birds of Hawaii. 

Working with John Sincock, USFWS refuge manager Gene 

Kridler, and State wildlife biologists Ernie Kosaka, David 

Woodside, and Ronald Walker, he identified the information 

needs that were most important to recovering the endangered 

species of Hawaii. It was not the “niche differentiation studies 

of endemic Hawaiian birds” (MacArthur and Levin, 1961) 

that Mike had envisioned when he accepted the position of 

endangered species biologist with the USFWS. The questions 

to which managers needed answers were far more policyand management-relevant. The decision-making process for 

recovery planning and implementation required answers to 

questions such as: Which species are extant? Where can they 

be found? How many are there? How do their distribution and 

density vary geographically? Who owns/manages the land, 

and what is its conservation status? The information gained 

from answering these questions could be used by managers to take the first two steps toward conserving Hawaii’s 

endangered forest birds—identifying and securing essential 

imperiled species habitat. It became clear to Mike and his colleagues that to answer those questions an extensive survey of 

all remaining forest bird habitat in the islands was needed. The 

result of their planning was the Hawaiian Forest Bird Survey 

(HFBS), a program to survey all remaining forest bird habitat 

in the islands, from the tree line down to the cane fields or the 

coast, on all the main islands in Hawaii with the exception of 

Oahu. The forest birds of Oahu were surveyed separately by 

others (Shallenberger and Vaughn, 1978).

Prior to launching the HFBS in 1976, a population survey 

was conducted to determine the distribution and abundance 

of the palila (Loxioides bailleui). That effort was led by 

University of Hawaii graduate student Charles Van Riper, 

whereas Mike Scott and David Woodside of the HDFW took 

the lead on the multiagency effort. They laid transects throughout the dry mamane (Sophora chrysophylla) and naio (Myoporum sandwicense) forests of the upper elevations of Mauna 

Kea, where the last remaining palila resided (Van Riper and 

others, 1978). These surveys, covering the entire geographical, 

geophysical, and ecological range of the palila, were repeated 

in 1980, and have been repeated every year since then (Jacobi 

and others, 1996; Banko and others, 2009). That standard—the 

surveying of the entire range of a species—was used for the 

larger HFBS (described below) that followed.

With funding and administrative support from the management side of the USFWS, logistical support from Ernie 

Koska and others from the HDFW, and leadership from John 

Sincock and Mike Scott, this historic undertaking (Pratt and 

others, 2009a) was launched in the Kau Forest on the island of 

Hawaii in the spring of 1976 (U.S. Fish and Wildlife Service, 1976a, b; 1977) and concluded on the island of Kauai 

in the summer of 1981 (Scott and others, 1986). Observers 

were selected from applicants who were screened for birding 

experience, physical fitness, hearing acuity, birding ability, 

familiarity with Hawaiian birds, and ability to spend extended 

periods in remote locations to conduct field studies. All field 

folks were trained in distance estimation and the audio, behavioral, and visual characteristics of the forest birds of Hawaii, 

as well as safety and sampling protocols (Kepler and Scott, 

1981; Ramsey and Scott, 1981; Scott and others, 1986). Members of that first year’s survey team, particularly Jim Jacobi, 

provided input to the study design that resulted in adding 

surveys for mapping rare and endangered plants and increased 

documentation of feral animal presence to the survey protocols. To supplement the quantitative capabilities of the group, 

Scott asked Fred Ramsey, longtime friend, lifelong birder, and 

professor in the statistics department at Oregon State University, to join the team to provide the statistical and analytical 

rigor needed to fully analyze the survey findings (Ramsey and 

others, 1979, 1987; Ramsey and Scott, 1978, 1979, 1981).

By the time the last sampling station was surveyed, 

members of the HFBS had recorded 30 native species and 33 

nonnative species; counted hundreds of thousands of birds; 

characterized vegetation (Jacobi, 1983, 1989; Jacobi and Scott, 

1985); and documented the occurrence of nonnative plant species (Warshauer and others, 1983), damage from feral animals, 

the presence of rare plants, and the discovery of new ones 

(Warshauer and Jacobi, 1982) at 9,940 survey stations during 20,789 count periods along 876 miles of transects (Scott 

and others, 1986). A dozen or so new species of plants were 

described and much new information was gained on the distribution and abundance of rare plants from the botanical collections created by James Jacobi, Rick Warshauer, Holly McEldowney, and others. Throughout Mike’s tenure in Hawaii, his 

wife, Sharon, played a key role in his research, making radio 

checks with field crews; picking up team members at the end 

of a transect; and serving as professional sounding board, editor, and all-around advisor for Mike.
Endangered Species Research Program

Endangered Species Research in Hawaii: The Early Years (1965–87) 187

The results of the HFBS were published in “Forest Bird 

Communities of the Hawaiian Islands” (Scott and others, 

1986) and many other peer-reviewed publications that are 

described elsewhere. The 1986 synthesis received The Wildlife Society’s Best Monograph Award. A review of the book 

characterized the HFBS as “a biological exploration of a high 

order and an excellent demonstration of applied statistics and 

despite my gloomy prediction, ecology of a high order...a 

model for other federal agencies charged with conservation 

programs” (Pimm, 1988). The complete electronic records 

of bird observation and transect locations of the HFBS are 

archived at the U.S. Geological Survey (USGS) Kilauea field 

station on the island of Hawaii (R.J. Camp, U.S. Geological 

Survey, written commun., 2010). The results of the HFBS 

complemented earlier statewide surveys of waterbirds (Engilis 

and Pratt, 1993; Reed and others, 2007; Swedberg, 1967) and 

game birds (Schwartz and Schwartz, 1949). Mike left Hawaii 

in 1984 to supervise the condor research effort in California.

Cam Kepler arrived in Maui in 1977 and joined the 

HFBS then underway on the Hamakua coast. Kepler participated in the surveys of Kona, Kohala, and Mauna Kea, including the extensive training sessions each spring (Kepler and 

Scott, 1981) in the years that followed. In 1980–81, he was 

coleader of the surveys of Maui, Molokai, Lanai, and Kauai.

During the HFBS, variable circle point counts for birds 

were conducted only in the first 4 hours of the day, weather 

permitting. This schedule provided time in the afternoons, 

after camp was set up, to make incidental observations in the 

study area. On May 12, 1981, during an incidental bird survey, 

Cam Kepler discovered the first nest of the small Kauai thrush 

(Myadestes palmeri) in a streamside cliff in one of the many 

embedded streams in the Alaka’i Swamp, on Kauai (Kepler 

and Kepler, 1983). All 13 small Kauai thrushes observed in 

the HFBS counts were also in deep gorges with flowing water, 

a finding consistent with observations made over 700 days in 

the Alaka’i by John Sincock (Scott and others, 1986). Knowledge of the microhabitats and nest-site locations of this endangered species allowed for more robust population estimates 

and management of the small Kauai thrush in subsequent 

years (Woodworth and others, 2009).

From 1977 to 1981, Cam and his wife, Kay Kepler, initiated surveys of several offshore islands to assess their seabird 

populations and plant communities (Kepler and Kepler, 1980; 

Kepler and others, 1984, 1990; Simons and others, 1985). All 

four islands hold breeding colonies of wedge-tailed shearwaters and Bulwer’s petrels (Bulweria bulwerii). The information 

from the surveys was made available to the Hawaii Department of Land and Natural Resources (DLNR) to inform their 

management activities on the seabird islands.

In 1978 and 1979, Cam studied the water birds of Kealia 

and Kanaha Ponds on Maui. Kanaha Pond was protected 

as a State bird sanctuary, but the much larger Kealia Pond 

was privately owned. He found that most of the endangered 

Hawaiian stilts (Himantopus mexicanus knudseni) frequently 

left Kanaha to feed at Kealia, and that the two wetlands 

were strongly linked, both being essential to the survival of 

the stilt and Hawaiian coot (Fulica alai). In 1984, Cam was 

asked to provide biological information about Kealia to the 

Maui County Council, which was considering changing the 

wetland to a development district (harbor development was a 

possible use). Because of information provided by Cam and 

others (Shallenberger, 1977), Kealia was retained in conservation district zoning. Cam also provided his results to Federal 

and State agencies as well as nongovernmental organizations. After years of deliberation, the USFWS made plans to 

acquire Kealia Pond (http://www.fws.gov/kealiapond/) as a 

wildlife refuge.

In 1984, following completion of the HFBS, Cam 

initiated an expanded research program on the ecology of 

Hanawi’s forest birds, including biological stresses affecting them. In 1986, Cam found the first nest of the po’o-uli 

(Melamprosops phaeosoma), and he, with Andy Engilis and 

Marie Ecton (USFWS), monitored this and a second (renesting) nest (Kepler and others, 1996; Engilis and others, 1996).

During their studies of the po’o-uli, the team noted a 

sobering increase in pig activity in the area (Mountainspring 

and others, 1990; Engilis, 1990). Habitat destruction by 

pigs resulted in soil loss of as much as 3 inches per year in 

Maui’s primary watershed, far more than previously had been 

suspected. Cam’s studies of the damage being caused by pigs 

to Hawaii’s native ecosystems complemented those of others 

(Stone, 1985; Stone and Stone, 1989). This information and 

the briefings by Cam and others to media and public agencies 

alerted decision makers and the public to the threat pigs posed 

to endangered species and the public water supply.

During this same period, Haleakala National Park initiated a multimillion-dollar program to fence its entire holdings 

and expanded its ungulate control program (Pratt and others, 

2009a). The Hawaii DLNR created the Hanawi Natural Area 

Reserve adjacent to The Nature Conservancy’s Waikamoi 

Preserve, and both organizations initiated their own fencing and control programs (Price and others, 2009). Kepler 

traveled to Athens, GA, in 1987 to study Kirtland’s warbler 

(Setophaga kirtlandii).

After Kepler left Hawaii, Patuxent maintained a research 

staff at the Kilauea field station that continued to study 

Hawaii’s imperiled flora and fauna. That research is summarized in Scott and others (2002) and Pratt and others (2009a).

The Science Policy Discourse: Making 

a Difference in Policy and on the 

Ground

In addition to publishing their findings widely in scientific journals, Mike Scott and others made repeated presentations on the conservation implications of the HFBS and 

their other studies to the Hawaii Department of Forestry and 
188 The History of Patuxent: America’s Wildlife Research Story

Wildlife and USFWS managers and biologists, as well as at 

many meetings of professional societies and conservation 

groups. By the late 1970s, word of the HFBS was spreading on the mainland and the conservation status of Hawaii’s 

imperiled biota had attracted increased attention from The 

Nature Conservancy. The Nature Conservancy’s Henry Little 

came to the islands in 1978. After becoming acquainted with 

the concept of the HFBS and its findings, he used the information from the HFBS to develop the Endangered Forest 

Bird Project. Working with Henry, Scott presented results of 

the HFBS and its implications for conservation of Hawaii’s 

endangered biota to The Nature Conservancy’s National 

Board of Directors in 1980. Funding for additional work by 

the Conservancy in Hawaii quickly became available. Henry 

used these funds to expand The Nature Conservancy’s work in 

the islands.

In 1980, Henry hired Kelvin Taketa and Hardy Spoehr, 

and together they launched the Endangered Forest Bird 

Project (The Nature Conservancy, 1982). The objective of this 

project was to use the results of the HFBS and other research 

efforts in the islands to identify the areas critical to for the 

conservation of Hawaii’s imperiled biota. The project’s steering committee was composed of community leaders. Sincock, 

Scott, and Kepler served on the project’s science advisory 

team along with National Park Service biologists and scientists from academia. In the fall of 1982, the Hawaii chapter 

of The Nature Conservancy was established. Henry Little 

quickly assembled a first-class board of trustees for the chapter, consisting of leaders in business, the nonprofit sector, and 

government. Realizing the importance of science-driven decision making, Henry Little tied the trustees to the science by 

using the Endangered Forest Bird Project’s science advisory 

board and Cam Kepler’s appointment to the Board of Trustees (1982–87) to bring science to the board’s conservation 

actions decision-making process. This organizational structure 

ensured a powerful flow of ideas between formerly disparate parts of the Hawaiian conservation community and the 

scientific community. The science board identified and ranked 

important factors that were essential to the survival of Hawaii 

imperiled species (The Nature Conservancy, 1982, 1983, 

1985), and gave that information to the Board of Trustees of 

the Hawaii chapter of The Nature Conservancy. The trustees quickly approved several areas for acquisition as nature 

reserves. The management challenges faced by the managers 

of those lands were identified in a “Save an Acre” commentary that was published in “Science” (Scott and Kepler, 1983). 

The response was phenomenal. By 1984, more than $4 million 

for conservation of endangered forest bird habitat had been 

brought into Hawaii, mostly in response to the information 

provided by the HFBS. Henry and Kelvin received the DOI 

Conservation Service Award in 1984 for their conservation 

efforts in Hawaii.

While The Nature Conservancy was conducting its 

conservation activities, Hawaii’s Natural Area Reserve System 

was identifying possible areas for designation as Natural 

Areas and the USFWS was screening areas for possible new 

wildlife refuges. The conservation efforts of these three groups 

were not entirely independent of each other, and each used 

shared resources to inform its decisions regarding establishment and design of new ecological reserves. Those decisions, 

made with the benefit of information from the HFBS and other 

sources, led to the designation of 12 protected areas, including 

the USFWS Hakalau Forest National Wildlife Refuge (http://

www.fws.gov/refuge/hakalau_forest) and an area in Kipahulu 

Valley on Maui that later became part of Haleakala National 

Park. Other Natural Area Reserves were established both 

independently and collaboratively by the Hawaii DLNR and 

The Nature Conservancy. These areas include Pu’u Maka’ala 

(http://dlnr.hawaii.gov/ecosystems/nars/hawaii-island/puumakaala/) and Pu’u O Umi Natural Area Reserves (http://dlnr.

hawaii.gov/ecosystems/nars/hawaii-island/puu-o-umi-3/) on 

the island of Hawaii (Scott and others, 1987b). The Nature 

Conservancy and the State established Waikamoi Preserve 

(http://www.nature.org/about-us/index.htm?intc=nature.tnav.

about) and the 7,500-acre Hanawi Natural Area Reserve 

(http://dlnr.hawaii.gov/ecosystems/files/2013/07/HanawiManagement-Plan.pdf) on Maui. The Nature Conservancy 

established Kamakou Preserve (http://www.nature.org/ourinitiatives/regions/northamerica/unitedstates/hawaii/placesweprotect/kamakou.xml) and Pelekunu (http://dlnr.hawaii.gov/

ecosystems/files/2013/09/Pelekunu-LRP-DRAFT-FINAL.

pdf), Olokui (http://dlnr.hawaii.gov/ecosystems/nars/reserves/

molokai/olokui/), and the 1,330-acre Puu Ali’i Natural Area 

Reserves (http://dlnr.hawaii.gov/ecosystems/nars/reserves/

molokai/puu-alii/) on Molokai.

On the island of Kauai, the 213-acre Kaluahonu Preserve easement to protect nesting sites of Newell’s shearwater 

(http://www.abcbirds.org/conservationissues/habitats/BCR/

hawaii.html) and the 3,579-acre Hono O Na Pali Natural Area 

Reserve (http://hawaii.gov/dlnr/dofaw/nars/reserves/kauai/

honoonapali) to conserve forest birds and rare plants were 

established. These and several other previously mentioned 

nature reserves on Kauai were established, in part, because 

of information provided by the work of Patuxent’s research 

biologists and their conservation partners.

The key to the quick application of information from the 

survey to the establishment of new protected areas for forest 

birds was the collaborative development of management- and 

policy-relevant research questions with managers and the 

continued involvement of the managers in conducting the 

survey, making the information available to decision makers 

in a user-friendly way (The Nature Conservancy, 1982, 1983, 

1985; Scott and others, 1986). The use of graphics showing 

the lack of overlap in the areas established and managed for 

their conservation value and the distribution of the birds of 

conservation interest was a particularly powerful tool (Scott 

and others, 1987b, 1993).

Many of the tools used in the HFBS have been used 

by others. The gap analysis process, first used as a means to 

identify gaps in the protected areas network for endangered 
Endangered Species Research Program

Endangered Species Research in Hawaii: The Early Years (1965–87) 189

Hawaiian birds (Scott and others, 1987a; Scott and others, 

1993), is used worldwide to assess the conservation status 

of species and ecosystems (Rodrigues and others, 2004a, b; 

see also http://gapanalysis.usgs.gov/about-gap/our-history/).

Every signatory to the Convention on Biological Diversity 

Treaty (http://en.wikipedia.org/wiki/Convention_on_Biological_Diversity) uses gap analysis to identify gaps in protection 

of their biological resources (http://www.cbd.int/doc/publications/cbd-ts-24.pdf), and GAP is an established program in 

the USGS (http://gapanalysis.usgs.gov/). Variable circular 

plots are widely used to estimate bird numbers (Estades and 

Temple, 1999). The 1980s rare bird surveys of the Micronesian Islands by John Engbring (USFWS), Fred Ramsey, and 

others used the methods and protocols of the HFBS to census 

the imperiled birds of Rota, Tinian, Aguijan, and Saipan (Engbring and others, 1986).

The translocation of Nihoa finches to new locations in the 

Leeward Islands by John Sincock and others was unsuccessful, but a population of Laysan finches persists today (2016)

on Pearl and Hermes Atoll because of a 1967 introduction 

by John and Gene Kridler (Morin and Conant, 1997; Conant 

and Morin, 2002). Newell’s shearwater can be found today at 

Kilauea Point National Wildlife Refuge on Kauai (http://www.

fws.gov/endangered/news/bulletin-spring2009/shearwatersof-kilauea-point.html) because of the translocation efforts 

of John and others. Those early translocation efforts in the 

Leeward Islands and Kauai demonstrated the results that could 

be achieved, and provided a model for the recent translocation efforts to decrease the risk of extinction for Laysan ducks 

(Anas laysanensis) and Nihoa millerbirds (Acrocephalus 

familiaris kingi) (Reynolds and others, 2008; U.S. Fish and 

Wildlife Service, 2014).

Finally, the Hawaiian crow is known to occur only in 

captivity (Banko, 2009; Lieberman and Kuehler, 2009). Its 

future as a wild bird lies with the captive flock made possible through the early efforts of Ernie Kosaka, Ah Fat 

Lee, Fern Duvall, and others in the HDFW and Win Banko 

to ensure that there would be options for the Hawaiian 

crow’s survival (http://blogs.sandiegozoo.org/2009/04/21/

hawaii-bird-program-open-house).

Our work in Hawaii differed in several ways from that 

done elsewhere in Patuxent’s Endangered Species Program. 

First, we were tasked with studying an entire avifauna, whose 

life histories, distribution and ecology, and indeed very existence were undocumented, whereas other programs focused 

only on a single species. In response to this challenge, we 

pioneered the development of ecosystem recovery plans for 

Hawaii’s birds (Kepler and others, 1984; Scott and others, 

1984; Sincock and others, 1984) rather than the single-species 

plans that were the standard in the 1970s and 1980s. We also 

developed new approaches for detecting and monitoring rare 

birds (Reynolds and others, 1980; Ramsey and others, 1979); 

however, the clinical interventions and captive propagation of 

individual animals that were a major component of many of 

Patuxent’s other endangered species field research efforts were 

only a minor part of ours. 

Where Do We Go From Here?

Nearly 50 years after the first endangered species 

research biologists arrived in the islands, what have we 

learned? As a result of the work of Patuxent’s biologists and 

other researchers from State and Federal agencies, nongovernmental organizations, and academia in the islands, we learned 

a lot about the rare things. We learned where they are and 

where they are not; new sampling methods for rare species; 

distribution, abundance, habitat associations, and biology 

of rare species; the nature of threats to survival of Hawaii’s 

endangered birds and plants; and the management actions 

needed to mitigate those threats. The take-away lessons from 

those early research efforts are sobering: recovery is slow and 

asking conservation-relevant research questions is a difficult 

process, but using the results of that research in a timely manner in the field to implement management actions at scales 

that increase the survival chances of a species is much more 

so. Our most important lesson may have been that the consequences of delaying or not implementing management actions 

are often irreversible.

The birds of Hawaii are still highly endangered (Gorresen 

and others, 2009; Pratt and others, 2009b). None of the birds 

unrecorded or insufficiently documented during the HFBS 

was reliably reported after the survey (Gorresen and others, 

2009). The chances that the unreported birds—for example, 

Kauai nukupuu (Hemignathus lucidus hanapepe) and Kauai 

akialoa (Hemignathus ellisianus stejengeri)—escaped detection are vanishingly small (Elphick and others, 2010; Gorressen and others, 2009; Reynolds and others, 2002; Scott and 

others, 1986, 2008; Sykes and others, 2000). Several birds 

observed during the HFBS—for example,‘o’u (Psittirostra 

psittacea) (Kauai and Hawaii), Kauai ‘o’o (Moho braccatus), 

large Kauai thrush (Myadestes myadestinus), Molokai thrush 

(Myadestes lanaiensis rutha), Maui akepa (Loxops coccineus 

ochraceus), Maui nukupuu, and po’o-uli—as well as the Oahu 

creeper (Paroreomyza maculata) observed on Oahu during 

surveys by Shallenberger and Vaughn (1978) have not been 

seen for 10 or more years. As mentioned above, one species, 

the Hawaiian crow, is known to occur only in captivity.

Why are these birds still endangered? For many of the 

species we were tasked with saving, we failed to eliminate 

or mitigate threats and restore habitat at temporal and spatial 

scales consistent with achieving recovery goals. The consequence of our failure to act at the necessary scales and speed 

to reduce threats was often extinction. None of the putatively 

“extinct” species, save possibly the po’o-uli (Groombridge, 

2009; Woodworth and others, 2009), benefited from the 

well-funded and intensive rescue efforts mounted for species 

like the California condor or peregrine falcon (Falco peregrinus). The work forces involved in several of those mainland 

conservation efforts commonly were larger than the population of the endangered species they were attempting to save. 

Unfortunately, for many other endangered Hawaiian birds, the 

resources to implement needed conservation efforts were not 

available and many of the management actions identified in 
190 The History of Patuxent: America’s Wildlife Research Story

the first recovery plans were not implemented or were implemented at scales that were not conservation-relevant.

For example, the first Kauai Forest Bird Recovery Plan 

(Sincock and others, 1984) called for removal of feral ungulates from the Alaka’i Swamp, the heart of the last remaining habitat for Kauai’s endangered forest birds, but the first 

ungulate fences were not built until 27 years later (http://dlnr.

hawaii.gov/ecosystems/files/2013/08/Proposal-Extensionof-Hono-o-Na-Pali-NAR.pdf). In the intervening three 

decades, three species on Kauai—Kauai ‘o’o, the ‘o’u, and the 

large Kauai thrush—have become extinct and two new species 

have been listed.

Similarly, the 1986 recovery plan for the palila called for 

removal of feral ungulates from critical habitat of the palila, 

a recommendation that was supported by two court decisions 

(Juvik and Juvik, 1984; Meltz, 1994). Twenty-six years later, 

although our knowledge of the ecology and biology of the 

palila has increased substantially (Banko and others, 2009), 

mouflon (Ovis gmelini musimon) are still found in critical 

habitat of the palila in large numbers and are being managed 

as a recreationally sustainable population for hunters, in part 

with Federal funds provided under the Pittman-Robertson Act 

(https://www.fws.gov/laws/lawsdigest/FAWILD.HTML).

Why was there a failure to implement management 

actions that were known to prevent extinction and promote 

recovery (Kepler and others, 1983; Scott and others, 1984; 

Sincock and others, 1984)? Current recovery efforts in Hawaii, 

the state with the highest density of endangered species per 

acre in the country, lag far behind those in other states in 

terms of conservation funds received. Hawaiian terrestrial 

vertebrates, 30 species, received $1.7 million, with 5 species 

(the Hawaiian crow, Hawaiian common moorhen [Gallinula 

chloropus sandvicensis], Newell’s shearwater, po’o-uli, and 

Hawaiian stilt) receiving 78 percent of those funds spent on 

Hawaii’s terrestrial vertebrates (U.S. Fish and Wildlife Service, 1996).

The situation is more complex than a lack of funds, however. In a thoughtful treatment of this question, David Leonard and others have suggested that lack of funding (Leonard, 

2008; Restani and Marzluff, 2002), lack of understanding of 

the plight of endangered birds in the islands, and failure to 

convince folks of the plight have contributed to an urgent need 

for conservation action. Additionally, there are substantial 

sociopolitical barriers to implementing conservation actions to 

benefit endangered forest birds related to conflicting management objectives for areas where endangered species occur (for 

example, sustaining a recreationally viable population of mouflon for hunters as opposed to maintaining the integrity, diversity, and health of palila habitat [Banko and others, 2009]). 

Where do we go from here? We have the advantage 

of nearly 50 years of research and the wisdom and insights 

gained from four decades of management actions, successful and unsuccessful; revised recovery plans for all but the 

northwestern passerine species; and a larger and more diverse 

conservation constituency with thousands of interested citizens 

and new citizen conservation groups (the Hawaii Conservation 

Alliance [http://hawaiiconservation.org/], Hawaii Association 

of Watershed Partnerships [http://hawp.org/], and Hawaiian 

Wetland Joint Venture [http://pcjv.org/hawaii/]) with which to 

work. These new institutional structures focused on maintaining the integrity of native ecosystems and their ecological 

processes will provide new perspectives on what actions are 

needed to save the remainder of Hawaii’s endangered ecosystems and species (Pratt and others, 2009b). Fortunately, 

working with the broader conservation perspectives offers new 

hope for the future of Hawaii’s endemic flora and fauna.

The ability of these conservation efforts to prevent 

extinction of additional species has been made more difficult, however, because of climate change, the increase in 

human population, and the need to act at landscape scales 

(Price and others, 2009). Finally, success will require more 

bridge building and collaboration among different constituencies, and major new commitments of collaboration and 

financial resources. 

Acknowledgments

The authors are grateful to Gene Kridler (U.S. Fish and 

Wildlife Service [USFWS]); Ernie Kosaka (Hawaii Department of Forestry and Wildlife [HDFW] and later USFWS); 

Henry Little and Kelvin Taketa (The Nature Conservancy); 

and Ron Walker and David Woodside (HDFW), our management advisory council during our research in the islands. We 

also thank all those who participated in the surveys, and Paul 

Banko (University of Washington student, and later USFWS); 

Sheila Conant (University of Hawaii); Ray Erickson, John 

Aloha from Hawaii—John Sincock and his assistant, Mike Scott, U.S. Fish and 

Wildlife Service, in their truck at the end of several days’ work, summer 1976. 

Photo by U.S. Fish and Wildlife Service.
Endangered Species Research Program

Endangered Species Research in Hawaii: The Early Years (1965–87) 191

Fay, Jim Jacobi, and Loyal Mehrhoff (USFWS); Thane Pratt 

(HDFW, and later USFWS); Fred Ramsey (USFWS summer 

employee from Oregon State University); Sharon Scott (Mike 

Scott’s wife); Rob Shallenberger (USFWS); Charles Van Riper 

(USFWS summer employee from the University of Hawaii); 

and Ron Walker (HDFW) for insights and comments on earlier 

versions of this manuscript. Our work in the islands benefited 

greatly from the administrative support provided by Ray 

Erickson and others at the Patuxent Wildlife Research Center. 

Finally, this research would not have been possible without 

Ray’s vision for an endangered species research program and 

his supervisory philosophy of “a big umbrella and long leash.”

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eds., 1981, Island ecosystems—Biological organization in 

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Pimm. S.L., 1988, Forest bird communities of the Hawaiian 

Islands—Their dynamics, ecology, and conservation, 

by J.M. Scott, Stephen Mountainspring, F.L. Ramsey, 

and Cameron Kepler (book review): Auk, v. 105, no. 2, 

p. 400-402. [Also available at http://www.jstor.org/

stable/4087519.]

Pratt, T.K., Atkinson, C.T., Banko, P.C., Jacobi, J.D., and 

Woodworth, B.L., eds., 2009a, Conservation biology of 

Hawaiian forest birds—Implications for island fauna: New 

Haven, CT, Yale University Press, 707 p.

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forest birds be saved?, in Pratt, T.K., Atkinson, C.T., Banko, 

P.C, Jacobi, J.D., and Woodworth, B.L., eds. Conservation 

biology of Hawaiian forest birds—Implications for island 

fauna: New Haven, CT, Yale University Press, p. 552–580.

Pratt, T.K., Kepler, C.B., and Casey, T.L.C., 1997, Poouli 

(Melamprosops phaeosoma), in Poole, A., and Gill, F., eds., 

the Birds of North America, no. 272: Philadelphia, PA, 

Academy of Natural Science, and the Washington, D.C., 

American Ornithologists’ Union, 16 p. [Also available at 

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Smith, C.W., 2009, Protecting forest bird populations 

across landscapes, in Pratt, T.K., Atkinson, C.T., Banko, 

P.C., Jacobi, J.D., and Woodworth, B.L., eds., Conservation 

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molting in six species of Hawaiian honeycreepers: Condor, 

v. 96, no. 1, p. 151–161. [Also available at http://sora.unm.

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available at https://sora.unm.edu/node/49.]

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scattering: Corvallis, OR, Oregon State University, Department of Statistics, Technical Report 60, 34 p.

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densities from variable circular plot surveys, in Cormack, 

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species under the Endangered Species Act—The need for a 

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1987b, Protecting endangered forest birds in Hawaii—The 

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S.I., 1988, Conservation of Hawaii’s vanishing avifauna—

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and Fefer, S.I., 1989, Integrated conservation strategy 

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Endangered Species Research Program

Endangered Species Research in Hawaii: The Early Years (1965–87) 195

Scott, J.M., Mountainspring, Stephen, Ramsey, F.L., and 

Kepler, C.B., 1986, Forest bird communities of the Hawaiian Islands—Their dynamics, ecology and conservation: 

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https://sora.unm.edu/node/56.]

Scott, J.M., Mountainspring, Stephen, Van Riper, Charles, III, 

Kepler, C.B., Jacobi, J.D., Burr, T.A., and Giffin, J.G., 1984, 

Annual variation in the distribution, abundance and habitat 

response of the palila (Loxioides balleiui): Auk, v. 101, 

no. 4, p. 647–664. [Also available at https://sora.unm.edu/

node/24018.]

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species on the ability of observers to make accurate counts 

of birds: Auk, v. 98, no. 3, p. 610–613. [Also available at 

https://sora.unm.edu/node/23582.]

Scott, J.M., and Ramsey, F.L., 1981b, Length of count period 

as a possible source of bias in estimating bird numbers, 

in Ralph, C.J., and Scott, J.M., eds., Estimating numbers of terrestrial birds: Studies in Avian Biology, no. 6, 

p. 409–413. [Also available at https://sora.unm.edu/

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estimation as a variable in estimating bird numbers from 

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no. 6, p. 334–340. [Also available at https://sora.unm.edu/

node/49.]

Scott, J.M., Ramsey, F.L., Lamertink, Martjan, Rosenberg, 

K.V., Rohrbaugh, Ron, Wiens, J.A., and Reed, J.M., 2008, 

When is an “extinct” species really extinct? Gauging the 

search efforts for Hawaiian forest birds and the ivory-billed 

woodpecker: Avian Conservation and Ecology, v. 3, no. 2, 

article 3 [n.p.], accessed September 9, 2016, at http://www.

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the birds of the Koolau Forest Reserve, Maui: Western 

Birds, v. 8, no. 3, p. 113–116. [Also available at https://sora.

unm.edu/node/122019.]

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‘Elepaio, v. 38, no. 3, p. 25–27.

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suppress mamane and other browse species on Mauna 

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105 p.

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in the central Koolau range, Oahu: Kailua, HI, Ahuimanu 

Productions, 51 p.

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1985, Hawaii’s seabird islands, no. 2—Hulu Island and 

vicinity, Maui: ‘Elepaio, v. 45, no. 11, p. 111–113.

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1984, Kauai Forest Bird Recovery Plan: Portland, OR, U.S. 

Fish and Wildlife Service, p. 1–69.

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akepa on the island of Hawaii: Wilson Bulletin, v. 92, 

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ecosystems—Preservation and management: Honolulu, HI, 

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on the life history and status of the Hawaiian duck (Anas 

wyvilliana): Honolulu, HI, Hawaii Department of Land and 

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196 The History of Patuxent: America’s Wildlife Research Story

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status of Vicia menziesii Spreng. (Leguminosae)—Hawai’i’s 

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p. 499–512.
Endangered Species Research Program

Patuxent’s Long-Term Research on Wolves

L. David Mech

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species.

Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and 

U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to 

the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota.

Endangered Species Act protection of the wolf fostered its quick population response, and wolf numbers began to 

increase in their reservoir in northeastern Minnesota and adjacent Canada and expand throughout northern Minnesota and eventually into Wisconsin and Michigan. In 2009, the number of wolves in Minnesota was approximately 

3,000, and there were at least 1,500 in Wisconsin and Michigan.

This chapter describes Patuxent’s wolf research, which continued into 1993 when Congress incorporated the 

USFWS’s Endangered Wildlife Research Program into the National Biological Survey (NBS). Eventually the NBS 

merged with the U.S. Geological Survey, and the long-term wolf research program was transferred to the Northern 

Prairie Wildlife Research Center. Through all the administrative changes, Patuxent’s wolf research project continued through the various agencies into the present (2016).

The text that follows is modified from Mech (2009).

The seeds for the blossoming of the wolf (Canis lupus) 

population throughout the upper Midwest were embodied in 

a long line of wolves that had persisted in the central part of 

the Superior National Forest (SNF) of northeastern Minnesota, probably since the retreat of the last glaciers more than 

10,000 years ago. This line of wolves had withstood not only 

the various natural environmental factors that had shaped them 

through their evolution, but also logging, fires, market hunting 

of prey animals, bounties, aerial hunting, and poisoning. These 

factors had exterminated their ancestors and dispersed their 

offspring to only a few wolf pack territories in the more accessible areas. The dense and extensive stretch of wild land that 

is now known as the Boundary Waters Canoe Area Wilderness 

had proven too formidable a barrier even for the foes of the 

wolf, which had striven to eliminate the animal and had succeeded everywhere else in the contiguous United States. The 

wolves of the SNF became the reservoir for the recolonization 

of wolves throughout Minnesota and into neighboring Wisconsin and the Upper Peninsula of Michigan.

The only other part of the 48 contiguous United States 

where wolves still survived in the late 1960s was Isle Royale 

in Lake Superior, just 32 kilometers (km) (20 miles [mi]) 

from Minnesota’s coast (Vucetich and Peterson, 2009). Those 

wolves had crossed Lake Superior’s rare ice bridge to the 

540-square-kilometer (km2

) (208-square-mile [mi2]) island 

from Ontario (or possibly Minnesota) in 1949. At that time, 

Isle Royale was a national park, and the wolves that reached 

the island were fully protected there from bounties, poisons, 

and aerial hunting.

Dave Mech, U.S. Fish and Wildlife Service, drugging wild wolf in Minnesota to 

radiocollar it, early 1970s. Photo by Don Elsing, U.S. Forest Service.
198 The History of Patuxent: America’s Wildlife Research Story

U.S. Fish and Wildlife Service wildlife technicians radiocollaring a wolf in 

Minnesota, mid-1980s. Photo by U.S. Fish and Wildlife Service.

The wolves of the central SNF also were those that wildlife biologist, wilderness enthusiast, and writer Sigurd Olson 

(1938) had trailed in the snow in the late 1930s and that Milt 

Stenlund (1955) had studied later. Although neither worker 

realized it, molecular geneticists would eventually debate 

whether the wolves they studied were a blend of animals 

descended from the most recent colonization of North America 

across the Bering land bridge (Canis lupus), such as those in 

northwestern Canada and Alaska, and wolves that putatively 

evolved in North America (Canis lycaon), such as those 

that inhabit southeastern Ontario (Wilson and others, 2000). 

Wolves with both types of genetic markers sometimes live 

in the same pack, and apparently many wolves in Minnesota 

are hybrids between the two types (Mech and Federoff, 2002; 

Wilson and others, 2009).

When the last remaining 700 or so wolves inhabiting 

Minnesota, most of them in the SNF, were placed on the Federal Endangered Species List in 1967, it was only logical to 

begin studying them. A few groundbreaking studies had provided some insights into the biology of wolves (for example, 

Olson, 1938; Murie, 1944; Cowan, 1947; Stenlund, 1955; 

Mech, 1966; Pimlott and others, 1969); however, because 

wolves were so scarce in the contiguous United States and 

lived in low densities and inaccessible areas where they did 

survive, much basic information about wolves was unknown. 

Fortunately, when wolves were declared endangered, wildlife 

researchers were beginning to apply the revolutionary technology of radiotracking (Cochran and Lord, 1963). Kolenosky 

and Johnston (1967) had proved in Ontario that radiotracking wolves was practical. This technique promised to greatly 

enhance the ability of researchers to discover many new things 

about the behavior and ecology of wolves.

In 1968, I began a pilot project in the central SNF using 

radiotracking to determine whether wolf packs were territorial 

(Mech and Frenzel, 1971). My preliminary aerial observations 

during 1966–67 and 1967–68 had shown that several packs 

of different sizes and color combinations were present in the 

area. Without reliable identifiers for each pack, however, and 

without being able to find packs systematically, I had only a 

subjective notion that they were territorial. Therefore, radiotracking wolves from aircraft, which allowed both identifying 

individuals and systematically locating them, was the ideal 

method to answer this question.

Study Area

My study area encompassed about 2,060 km2 (795 mi2) 

immediately east of Ely in the east-central SNF (48° N. 

Aerial radiotracking of wolves in Minnesota by U.S. Fish and Wildlife staff, mid1980s. Photo by U.S. Fish and Wildlife Service.Aerial observation of radiocollared wolves in Minnesota as part of the ongoing 

U.S. Fish and Wildlife Service wolf census, mid-1980s. Photo by U.S. Fish and 

Wildlife Service.
Endangered Species Research Program

Patuxent’s Long-Term Research on Wolves 199

92° W.). Although somewhat smaller than the areas I have 

reported on earlier, this area encompassed the core of that 

region in which I have been able to monitor the wolf population during the entire 40-year study (1966–2006) (fig. 1). The 

area represents only a small percentage of the total range of 

wolves in Minnesota.

Topography in the study area varies from large stretches 

of swamps and uneven upland to rocky ridges, with altitudes 

ranging from about 325 to 700 meters (m) (1,066–2,297 feet 

[ft]) above the National Geodetic Vertical Datum of 1988. 

Winter temperatures below -35 degrees Celsius (°C) 

(-31 degrees Fahrenheit [°F]) are not unusual, and snow depths 

(from about mid-November through about mid-April) generally range from 50 to 75 centimeters (cm) (20–30 inches [in.]). 

Summer temperatures rarely exceed 35 °C (95 °F). Conifers, 

including jack pine (Pinus banksiana), white pine (P. strobus), 

red pine (P. resinosa), black spruce (Picea mariana), white 

spruce (P. glauca), balsam fir (Abies balsamea), white cedar 

(Thuja occidentalis), and tamarack (Larix laricina), predominate in the forest overstory. As a result of extensive cutting and 

fires, however, much of the coniferous cover is interspersed 

with large stands of white birch (Betula papyrifera) and aspen 

(Populus tremuloides). Heinselman (1993) presents a detailed 

description of the forest vegetation.

In the northeastern half of this area, as well as immediately north and east of it, the overwintering population of 

white-tailed deer (Odocoileus virginianus) was extirpated by 

about 1975 by a combination of severe winters, maturing vegetation, and a large wolf population (Mech and Karns, 1977), 

and the area has remained devoid of wintering deer ever since 

(Nelson and Mech, 2006). Moose (Alces alces) inhabit the 

entire area but occur at a higher density in the northeastern 

half. In spring, about a third of the deer inhabiting the southwestern half of the study area migrate into the northeastern 

half or beyond and return in fall (Hoskinson and Mech, 

1976; Nelson and Mech, 1981). American beavers (Castor 

canadensis) occur throughout the study area, but generally are 

available as prey only from about April through November. 

Although all three prey species are consumed by wolves in the 

region (van Ballenberghe and others, 1975), the primary prey 

of wolves inhabiting the northeastern part has been moose 

since about 1975, whereas wolves in the southwestern part 

have consumed primarily deer.

Year-round hunting and trapping of wolves were legal 

until October 1970, when wolves were fully protected on Federal land within the SNF by the U.S. Forest Service. In August 

1974, wolves were protected under the Endangered Species 

Act of 1973. In 1978, wolves in Minnesota were reclassified as 

threatened, but remained legally protected except for depredation control outside the SNF (Fritts and others, 1992). Illegal 

taking of wolves continued, however—primarily in fall and 

winter (Mech, 1977b; Mech and Hertel, 1983). Wolves in the 

upper Midwest, including Minnesota, were removed from the 

Endangered Species List in March 2007.

CANADA

UNITED STATES

ONTARIO PROVINCE

Wolf census area

LAKE COUNTY

COOK COUNTY

LAKE SUPERIOR

ST. LOUIS COUNTY

SUPERIOR NATIONAL FOREST

91°

48°

0 25

25

MILES

0 KILOMETERS

Ely

Isabella

Figure 1. Location of the central Superior National Forest study area, Minnesota. (Modified from Mech, 2009)
200 The History of Patuxent: America’s Wildlife Research Story

Long-Term Research on Wolves, Wolf 

Packs, and Population Trends

My main objective at the beginning of the study was to 

determine spacing in the wolf population, but I also realized 

that by being able to find and identify each marked pack, I 

could obtain much additional information. For example, during winter I could count pack members, determine how consistently each pack maintained its size, track its movements, find 

and examine its kills, and locate marked wolves after death. In 

addition, if the packs were territorial, radiotagging a sufficient 

number of packs in the study area would allow me to determine the total number of wolves there by locating each pack 

and counting the pack members.

Over the long term, monitoring the population trajectory of wolves in the SNF became my primary objective. 

The longer this study continued, the more valuable the data 

on changes in population size became. The only other data 

available on wolf population trends were those from the Isle 

Royale study, which began in 1959 (Mech, 1966) and was 

continued by other researchers (Vucetich and Peterson, 2009). 

Although those data are of great interest, they characterize an 

island with no emigration or immigration and therefore cannot 

fully represent most populations of wolves. The opportunity to 

gather long-term data on a population of mainland wolves and 

determine the factors that drove the changes in that population 

was highly attractive.

The primary technique used has been live-trapping 

wolves in modified steel foot-traps, anesthetizing each animal 

(except most pups), weighing them, sampling their blood, and 

outfitting them with a radiocollar (Mech, 1974). Since 2000, 

my assistants, students, associates, and I also have estimated 

the age of each wolf on the basis of tooth wear (Gipson and 

others, 2000). We aerially radiotracked the wolves at least 

weekly during most years, and observed and counted them as 

often as possible, primarily from December through March 

(Mech, 1973, 1986). The largest number of wolves we saw 

during winter in each pack was considered to be the pack size. 

If the territory of a radiocollared pack fell partly outside the 

census area, the number of wolves assigned to the census area 

was multiplied by the percentage of the territory that fell in 

the area.

Territoriality of Wolf Packs

Each time we located a wolf, we recorded its location. 

We plotted these locations from October 1 through March 30 

and from April 1 through September 30 each year, and used 

minimum convex polygons (MCPs) (Mohr, 1947) to represent 

territories (Mech, 1973, 1977b, 1986).

Pack territories based on radio locations were delineated for each radiocollared pack in the study area each 

year; however, some packs died out, new ones formed, and 

not all packs were radiocollared each year. The existence 

U.S. Fish and Wildlife Service staff examining wolf-killed deer, Minnesota, 

mid-1980s. Photo by U.S. Fish and Wildlife Service.

of nonradiocollared packs in the study area in any year was 

inferred from voids in the maps of the territorial mosaic. Incidental observations of nonradiocollared packs and (or) their 

tracks in these voids indicated the sizes of these packs. (Some 

data pertaining to individual packs in some years in this chapter may differ from data presented previously [Mech, 1973, 

1977c, 1986] as a result of a reinterpretation of the data on the 

basis of additional experience with these packs.) If data on 

individual packs were unavailable for any year, pack-size estimates were made on the basis of the previous and subsequent 

years’ data for packs occupying those territories. Because an 

unknown portion of the territories of some of these packs may 

have fallen outside the census area, these data are not precise. 

Data collected in 1966–67 and 1967–68 were based solely on 

observations of nonradiocollared packs during intensive aerial 

observations. In the estimates of population trajectory for 

wolves presented here, I considered the number of lone wolves 

to be inconsequential because they represented only a small 

proportion of the population, and most of these individuals 

were dispersers accounted for by using the maximum numbers 

in each pack. During the earlier part of the study, lone wolves 

were estimated to constitute 7 to 14 percent of the population 

(Mech, 1973).

Because monitoring the population density of wolves 

in the study area required the maintenance of radiocollars on 

several adjacent packs, the project became a data-gathering 

system that allowed several parallel studies. Knowing where 

wolf packs lived regularly and how many members each 

contained allowed Fred Harrington and me to approach on 

foot and howl to them under various conditions to determine 

their responses (Harrington and Mech, 1979). By tracking 

known packs in the snow and examining their scent marks, 

Roger Peters and I could describe and quantify scent-marking 

behaviors (Peters and Mech, 1975). Russell Rothman and I 

conducted a similar study on newly formed pairs of wolves 

(Rothman and Mech, 1979).
Endangered Species Research Program

Patuxent’s Long-Term Research on Wolves 201

From 1968 through 2006, we live-trapped 712 wolves 

(119 female pups, 141 male pups, 239 females ≥1 year old, 

and 213 males ≥1 year old) in the study area, for a total of 

1,044 captures of wolves from 15 or more packs. The number of packs radiocollared each year varied, and over the 

38 years of radiotracking, some packs disappeared and many 

new ones formed. Weights of both males and females peaked 

at 5 or 6 years of age, with mean peak weights of 40.8 kg 

(89.9 pounds [lbs]) ± a standard error (SE) of 1.5 kg (3.3 lbs) 

and 31.2 kg (68.8 lbs) ± a SE of 2.4 kg (5.3 lbs), respectively 

(Mech, 2006a). From 2000 to 2004, the age structure of the 

population was relatively young, with only 12 percent of animals more than 1 year old being more than 5 years old (Mech, 

2006b). Some wolves, however, lived to be 13 years old 

(Mech, 1988). Most females 4 to 9 years of age had bred, as 

determined by assessing nipple sizes; those that had not bred 

had lower average weights than those that had.

The study clearly established for the first time that each 

radiocollared pack inhabited a separate territory (Mech, 1973). 

Pimlott and others (1969, p. 78) had concluded that “the 

results are far from conclusive on the question of whether or 

not pack territoriality is involved,” and Mech (1970, p. 105) 

had speculated that wolf packs might even have “spatiotemporal” territories. Radiotracking wolves in the SNF 

showed that they are territorial and that their territories are 

spatial (Mech, 1973). The wolves advertised and defended 

their territories by howling (Harrington and Mech, 1979), 

scent-marking (Peters and Mech, 1975), and direct aggression 

(Mech, 1994).

Analysis of wolf-pack territory size was not in the scope 

of this study. On the basis of MCPs of radiocollared wolf 

packs, territory sizes varied from 125 to 310 km2 (48–120 mi2) 

through winter 1973 (Mech, 1974). During 1997–99, however, 

the Farm Lake pack inhabited only 23 to 33 km2 (9–13 mi2), 

a density of 182 to 308 wolves per 1,000 km2 (472–798 per 

1,000 mi2), the highest density ever reported (Mech and Tracy, 

2004). The overall territorial structure gradually shifted over 

the years, although some semblance of the early structure was 

still apparent in 2006–07 (fig. 2).

Maximum winter pack sizes during 233 radiocollared 

pack-years (1 pack radiotracked for 1 year = 1 pack-year) varied from 2 to 15 and averaged 5.6 ± 0.20 (SE). Maximum winter pack sizes for 11 packs with at least 11 years of data varied 

from 2 to 8 to 2 to 15 per year, with means of 3.7 ± 0.5 (SE) 

to 7.9 ± 1.1 (SE); the small standard errors around these 

means show that individual packs in the study area tended to 

retain their basic sizes. Approximately 67 percent of the packs 

included a maximum of two to six members during winter, and 

90 percent included two to nine (fig. 3).

One of the more novel findings of our long-term study 

was the concept of the buffer zone between wolf-pack territories (Mech, 1977c). There appears to be an area of 1 to 

2 km (0.6–1.3 mi) around the edge of a wolf-pack territory 

where neighboring packs travel but spend little time (Mech 

and Harper, 2002), and wolves fight there, commonly to the 

death, if an encounter between packs occurs (Mech, 1994). 

Therefore, prey seem to survive longer in these zones. When 

the deer population declined early in the study, most of those 

Ely

Isabella

ONTARIO PROVINCE

Ely

Isabella

ONTARIO PROVINCE

Ely

Isabella

ONTARIO PROVINCE A B C

EXPLANATION

0 25

25

MILES

Wolf pack minimum convex polygon 0 KILOMETERS

Wolf census boundary

Figure 2. Territorial structure of wolf packs in the central Superior National Forest study area, Minnesota. A, 

represents the territorial structure from 1971 to 1973, but arbitrarily extends each pack’s minimum convex polygon 

(MCP) to the boundaries of its neighbors (Mech, 1973). B, represents the actual MCPs for radiocollared packs 

during winter 1984–85 (Mech, 1986). C, represents the same for 2006–07. In 1984–85, a nonradiocollared wolf 

pack consisting of an estimated six wolves occupied an unknown part of the northeastern area, and in 2006–07, 

a nonradiocollared pack of eight wolves occupied the northeastern area. Several aerial surveys over the eastcentral area indicated that no wolves were present during winter 2006–07. (Modified from Mech, 2009)
202 The History of Patuxent: America’s Wildlife Research Story

2 3 4 5 6 7 8 9 10 11 12 13 14 15

Wolf pack size

0

7

14

21

28

35

42

Frequency

Figure 3. Distribution of maximum winter pack sizes in the central Superior National Forest 

study area, Minnesota, winter 1966–67 through winter 2006–07. (Modified from Mech, 2009)

remaining inhabited these zones (Hoskinson and Mech, 1976; 

Mech, 1977a, c; Nelson and Mech, 1981). Even after the deer 

population increased, we continued to find evidence of this 

relation (Kunkel and Mech, 1994).

Buffer zones between territories of wolf packs are important to territorial maintenance. In addition to fighting, adjacent 

packs scent-mark disproportionately there (Peters and Mech, 

1975). Howling in and near the buffer zone undoubtedly also 

is important. Harrington and Mech (1979, p. 243) estimated 

that each pack on average is within howling range of at least 

one neighboring pack about 78 percent of the time, and “the 

probability of one pack hearing another, and the probability of 

encounters both increase when packs approach one another at 

a common border.”

Population Trends

In our 2,060-km2 (795-mi2) study area, numbers of 

wolves ranged from 35 to 87 with a mean of 59 and a median 

of 55, and a density of 17 to 42 wolves per 1,000 km2

(44–109 per 1,000 mi2) with a mean of 28 per 1,000 km2

(73 per 1,000 mi2) and median of 27 per 1,000 km2 (70 per 

1,000 mi2). The population decreased between the winters of 

1968–69 and 1973–74 and subsequently increased (r2 = 0.33; 

P < 0.001) (fig. 4). Mean pack size also increased after 

winter 1973–74 (r2 = 0.21; P < 0.01). In winter 2006–07, 

the population was estimated to be 81 wolves, or 39 wolves 

per 1,000 km2 (101 per 1,000 mi2). Both the population and 

average-pack-size trends increased after 1973–74 at a mean 

annual rate of 0.01. Annual changes in the estimated size of 

the wolf population were related to annual changes in mean 

sizes of radiocollared packs (r2 = 0.35; P < 0.001). Estimates 

of pack-size and population change were accurate because 

radiocollared packs were easily located and counted several 

times each winter.

From the beginning of the study through about the late 

1980s, the proportion of wolves on a deer economy in our area 

decreased, and more wolves had to rely on moose. The decline 

in wolves through 1982 coincided with the decline in deer 

(fig. 5), which in turn coincided with maximum cumulative 

3-year snow depth (Mech and others, 1987a). When the snowfall moderated in 1982–83, the number of deer began increasing again (Fuller and others, 2003). The trend for the wolf population that depended on deer declined curvilinearly, reaching 

a minimum about 1991 and gradually increasing through 2007 

(r2 = 0.86; P < 0.00001). The wolf population in the northern, 

northeastern, and eastern parts of the area that preyed increasingly on moose showed a reverse-sigmoid increase (r2

 = 0.80) 

from about 1978 through 2007, related (r2 = 0.12; P = 0.06) to 

an increase in abundance of moose from 3,900 individuals in 

1978 to 6,460 in 2007 (Mark Lennarz, Minnesota Department 

of Natural Resources, written commun., 2006).

Canine parvovirus (CPV) began affecting the SNF 

wolf population in the early 1980s and had its greatest effect 
Endangered Species Research Program

Patuxent’s Long-Term Research on Wolves 203

0

90

80

70

60

50

40

30

20

10

Number of wolves

1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

Figure 4. Size of the wolf population in the central Superior National Forest, MN, 1967–2007. 

(Modified from Mech, 2009)

Wolf

Deer

1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

Deer population in southeastern parts of the study area

Wolf population in southeastern parts of the study area

0

500

1,000

1,500

2,000

2,500

3,000 100

0

20

40

60

80

90

70

50

30

10

Figure 5. Size of the deer (1967–2005) and wolf (1967–2007) populations in southeastern parts of the 

central Superior National Forest study area, Minnesota. (Modified from Fuller and others, 2003, fig. 6.6)
204 The History of Patuxent: America’s Wildlife Research Story

from 1987 to 1993, after which the wolf population gained 

resistance (Mech and Goyal, 2011). From 1987 to 1993, the 

annual change in the wolf population was negatively related 

to seroprevalence of CPV (r = -0.92; P = < 0.01). The relation 

between CPV seroprevalence and an index of survival of wolf 

pups was r =- 0.73 (P = 0.06) (Mech and Goyal, 2011).

Dispersal

The wolf population occurred at a high density, and packs 

occupied most of the available space. Any excess production 

of pups therefore resulted in their dispersal as 1- to 3-yearolds (Mech, 1987; Gese and Mech, 1991). Some dispersers 

became nomadic in the general vicinity of their natal population, covering as much as 4,100 km2

 (1,577 mi2) (Mech and 

Frenzel, 1971; Mech, 1987). Others, however, dispersed 

farther and helped recolonize other parts of Minnesota, as well 

as Wisconsin and Michigan (Mech and others, 1995; Merrill 

and Mech, 2000).

Studies of Deer Ecology

As I radiotracked wolves, it became clear that a thorough 

study of wolf ecology would require examination of the natural history and ecology of their main prey, white-tailed deer. 

In 1973, I began radiotagging deer in the same area and traced 

their movements, survival, and mortality along with those of 

the radiocollared wolves. Reed Hoskinson, University of Minnesota (Hoskinson and Mech, 1976), and then Mike Nelson, 

U.S. Fish and Wildlife Service (Nelson and Mech, 1981; 

Nelson, 1993), conducted the initial studies of deer. Mike 

remained with the project as a collaborator in charge of deer 

research (DelGiudice and others, 2009). Ted Floyd joined us 

as a graduate student and used our radiotagged deer to pioneer 

the technique of evaluating observability biases in aerial ungulate censuses, applying an adjustment for observability to our 

data (Floyd and others, 1979). We used this technique to count 

deer in winter through 1992 (Nelson and Mech, 1986a), until 

funding constraints forced us to discontinue it. Since 1992, we 

have used buck harvest in part of our area to index deer population trend. The number of deer in our area decreased from 

the late 1960s and 1970s, reached a minimum about 1981, and 

has slowly and intermittently increased since then (fig. 5).

From 1973 to 2007, we radiocollared 347 deer, mostly 

females. In addition to learning much basic natural history 

about these deer (for example, Hoskinson and Mech, 1976; 

Nelson and Mech, 1981, 1987, 1990; Nelson, 1993; Mech and 

McRoberts, 1990), we found that wolves rarely killed adult 

females during summer (Nelson and Mech, 1986c), that wolf 

predation was greatest when snow was deepest (Nelson and 

Mech, 1986b), that daily predation rates during fall migration were 16 to 107 times those of deer in wintering areas or 

yards (Nelson and Mech, 1991), that survival of adult females 

was related to the nutritional condition of their mothers, 

and that survival of yearlings to 2-year-olds was related to 

the nutritional condition of their grandmothers (Mech and 

others, 1991).

We learned that condition was an important factor predisposing deer to predation by wolves, and various measures 

of condition provided evidence. Wolves tended to kill old deer 

(Mech and Frenzel, 1971; Mech and Karns, 1977; Nelson 

and Mech, 1986a); deer with abnormalities (Mech and others, 

1970; Mech and others, 1971; Mech and Karns, 1977); deer 

with low blood fat (Seal and others, 1978); deer with low marrow fat (Mech and Frenzel, 1971; Mech, 2007); and newborn 

fawns of below-average weight and (or) with low serum urea 

nitrogen (Kunkel and Mech, 1994).

Deer condition in winter depends on snow depth because 

the deeper the snow, the more difficult it is to find food 

(Verme, 1968). Therefore, we were not surprised to find that 

the size of, and trend in, deer populations were related to snow 

conditions (Mech and others, 1971; Mech and Karns, 1977; 

Mech and others, 1991; Mech and others, 1987a; McRoberts 

and others, 1995; but see Messier, 1995).

Follow-Up Studies from, and Adjuncts 

to, the Superior National Forest Wolf 

Research

While trapping wolves in the SNF, I quickly realized that 

if we could capture them more easily, we could examine them 

more often and better monitor their weight, blood values, and 

condition. Furthermore, the early collars we used commonly 

did not last even 1 year, so replacing them was important. 

The longer data were collected, the more complete a picture 

we could gain of the natural history of packs and the spatial 

organization of the population.

To determine whether radio signals could be used to 

remotely dart and recapture a radiocollared wolf, I consulted 

my former coworker, Bill Cochran (University of Minnesota), 

who had pioneered radiotracking (Cochran and Lord, 1963). 

Cochran suggested using a squib—an electrically detonated 

matchhead, like a tiny flashbulb. When a signal sends current 

through the squib, it flashes. Gunpowder in front of the squib 

detonates, drives a dart, and injects a drug. This technique, 

however, requires a radio receiver attached to the dart to pick 

up the signal, and an electrically detonated dart small enough 

to be attached to a wolf collar. The dart also has to be wolfand waterproof, and in a position to inject a drug into a wolf. 

We designed the mechanism, but needed a talented machinist 

to produce the experimental prototypes. Lee Simmons, Director of the Henry Doorly Zoo in Topeka, KS, came to the rescue. Ulysses (Ulie) Seal of the U.S. Veterans Administration 

Hospital, Minneapolis, MN, and an expert on drugs suitable 

for use in such a collar (Seal and others, 1970), completed the 

development team.
Endangered Species Research Program

Patuxent’s Long-Term Research on Wolves 205

The time between conception and availability of a working dart collar was about 10 years. Sometime during the final 

development, Rick Chapman, a graduate student on the project, was hired by 3M Company, which had sufficient interest 

in the concept of the collar to invest considerable time and 

funding to perfect it (Mech and others, 1984).

We also tested the capture collar on several deer (Mech 

and others, 1990) and used it to conduct studies of year-round 

nutritional condition in deer (DelGiudice and others, 1992) 

and of capture stress (DelGiudice and others, 1990). We then 

tested the collar successfully on wild wolves (Mech and Gese, 

1992) and used it to obtain such elusive types of data as serial 

weights and blood values on the same wolf over long periods, 

as well as field metabolic rates (Nagy, 1994). The most important contribution of the capture collars, however, was unexpected. To facilitate recovery of the collar in case it failed, 

Chapman invented a remote-release mechanism. When that 

mechanism was applied to global positioning system (GPS) 

collars, then being developed, biologists could retrieve the 

GPS collars to download the data (Merrill and others, 1998). 

Unfortunately, because commercial companies found it much 

more lucrative to produce GPS collars than capture collars, 

the latter soon became unavailable.

Blood Sampling

During the 1970s, Ulie Seal began studying aspects of 

blood that had direct application to our studies. I then began a 

productive collaboration with him, collecting blood from both 

wolves and deer. Although my main objective was to determine the nutritional condition of my study animals (Seal and 

others, 1975; Seal and others, 1978), the samples gained more 

significance for their usefulness in determining seroprevalence of CPV in our wolves (Mech and Goyal, 2011).

Studies of Captive Wolves

As these projects produced new information, they also 

spawned many questions. Some could be answered with additional field studies, but others required a different approach. 

Therefore, Jane Packard (Texas A&M University), Ulie Seal, 

and I set up a colony of captive wolves that could be observed 

closely and examined frequently, blood-sampled, and otherwise studied intensively (Seal and others, 1987; Seal and 

Mech, 1983; Packard and others, 1983, 1985). As that project 

grew, Cheri Asa, St. Louis Zoo (Asa and others, 1985; 1990), 

James Raymer, University of Indiana (Raymer and others, 

1985, 1986); and Terry Kreeger, University of Minnesota 

(Kreeger and others, 1990, 1997) became additional collaborators. Glenn DelGiudice (University of Minnesota Ph.D. 

student) made use of both the captive wolf colony (Mech and 

others, 1987b) and the field studies in the SNF (DelGiudice 

and others, 1988, 1989) to begin investigations of the nutritional condition of various animals by using analyses of urine 

in the snow.

Beyond the Superior National Forest

Several other spin-offs of research in the SNF increased 

our knowledge of wolves and wolf recovery in the Midwest 

and elsewhere. Because radiotracking was so productive in the 

SNF where the wolf population had been long established and 

occurred at high density, I wanted to use the same techniques 

to examine a recently colonized wolf population. For this I 

recruited Steve Fritts (USFWS) to study a recently established 

wolf population 290 km (181 mi) away in northwestern Minnesota (Fritts and Mech, 1981).

We also assisted the Minnesota Department of Natural Resources in starting a research project on wolves in 

north-central Minnesota similar to the SNF study. We taught 

colleagues, students, and technicians how to live-trap, anesthetize, radiotag, and radiotrack wolves. Many of them continued 

research on wolves in other areas (Berg and Kuehn, 1982; 

Fuller and others, 2003; Boyd and others, 1995; Meier and 

others, 1995; Burch and others, 2005; Ream and others, 1991). 

Furthermore, we conducted an experimental reintroduction 

of four wolves into northern Michigan that demonstrated that 

translocated wolves held for a week tended to return homeward (Weise and others, 1979).

Biologists in other areas became interested in doing 

similar studies, so I was invited to Italy; to Riding Mountain 

National Park, Canada; and to Alaska to help organize their 

first radiotracking studies of wolves (Boitani and Zimen, 

1979; Carbyn, 1980; Peterson and others, 1984). Some of my 

technicians helped start projects in Portugal and Romania. 

Furthermore, the Patuxent wolf project hosted biologists from 

Sweden, Israel, Portugal, Poland, Spain, Croatia, India, Italy, 

Mexico, Norway, Turkey, and Austria to receive training in 

wolf research techniques in the SNF study area.

Wolf Depredation Control Program

Responses to complaints about livestock depredation had 

been managed by the Animal Damage Control Branch of the 

USFWS, but in 1978, when wolves in Minnesota were reclassified from endangered to threatened, I was asked to design a 

control program for wolves. This program had to stay within 

the directives of a court order while still attempting to reduce 

wolf depredations on livestock—that is, taking a minimal 

number of wolves, yet satisfying farmers and ranchers. I was 

appointed to direct the program, and I assigned Steve Fritts, 

with his newly minted Ph.D. degree, to run it. Bill Paul, a 

newly hired technician on the SNF project, was his main assistant. These two workers conducted a well-respected program 
206 The History of Patuxent: America’s Wildlife Research Story

that continues under the auspices of the U.S. Department of 

Agriculture Wildlife Services (Fritts and others, 1992).

We tried many alternative nonlethal methods to reduce 

losses of livestock, such as translocating depredating wolves 

(Fritts and others, 1985), and using “fladry” (flagging), blinking lights, guard dogs, and taste aversion (Fritts and others, 

1992), and conceived several other methods such as radiocontrolled shock collars, radioactivated alarm systems, humanapplied scent marking, and recorded howling. None proved to 

be very effective or practical because the law allowed lethal 

control and the population was not so low (1,250 in 1978) that 

every last member needed to be preserved at all costs. Some of 

these concepts have since proved useful where lethal control is 

allowed or where wolf numbers are so low that extraordinary 

means are justified (Shivik, 2006; Musiani and others, 2003; 

Schultz and others, 2005). Fritts eventually was promoted to 

assistant leader of the Endangered Species Wildlife Research 

Program at Patuxent under leader Randy Perry, who had 

assumed Erickson’s position when he retired. Fritts later went 

on to head the USFWS’s wolf reintroduction into Yellowstone 

National Park with Ed Bangs.

Future Directions

To understand the functioning of natural wolf populations, it is important to follow the long-term trend of at least 

one long-extant population. The value of the information that 

science has obtained from the Isle Royale wolf population 

over 50 years is immeasurable (Vucetich and Peterson, 2009); 

however, the fact that the population is restricted to an island 

with no regular immigration or emigration is problematic. 

Because the central SNF study is the longest running, nonisland study of a wolf population, continuing this investigation as long as possible is critical. Patuxent deserves credit 

for supporting this important work during its first two and a 

half decades.

Acknowledgments

This study was supported during its entirety by the U.S. 

Department of the Interior through the U.S. Fish and Wildlife 

Service (USFWS), the National Biological Survey, and the 

U.S. Geological Survey (USGS) (Patuxent, Midcontinent, and 

Northern Prairie Wildlife Research Centers), as well as by the 

U.S. Forest Service through the North Central Forest Experiment Station (now the North Central Research Station) and the 

Superior National Forest. Private funding sources included the 

New York Zoological Society, the World Wildlife Fund, the 

Mardag Foundation, the Special Projects Foundation of the 

Big Game Club, Wallace Dayton (Big Game Club), and Valerie Gates (Gates Family Foundation). I especially thank M.E. 

Nelson, J.J. Renneberg, and Tim Wallace (USFWS) as well 

as the many volunteers and graduate students who assisted 

with the field work. Shannon Barber-Meyer (USGS) and D.J. 

Demma (Alaska Department of Fish and Game) critiqued an 

early version of the manuscript and offered helpful suggestions for improvement.

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Seasonal metabolic and reproductive cycles in wolves, 

in Frank, H., ed., Man and wolf—Advances, issues, and 

problems in captive wolf research: Boston, Dr. W. Junk 

Publishers, p. 109–125. 

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lupus) on the Superior National Forest: Minnesota Department of Conservation Technical Bulletin, v. 4, 55 p.

Van Ballenberghe, Victor, Erickson, A.W., and Byman, David, 

1975, Ecology of the timber wolf in northeastern Minnesota: Wildlife Monographs No. 43, p. 3–43. [Also available 

at http://www.jstor.org/stable/3830388.]

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v. 32, no. 3, p. 566–574. [Also available at http://dx.doi.

org/10.2307/3798937.]

Vucetich, J.A., and Peterson, R.O., 2009, Wolf and moose 

dynamics on Isle Royale, in Wydeven, A.P., Van Deelen, 

T.R., and Heske, E.J., eds., Recovery of gray wolves 

in the Great Lakes Region of the United States—An 

endangered species success story: New York, Springer 

Science+Business Media, p. 35–48. [Also available at http://

dx.doi.org/10.1007/978-0-387-85952-1_3.]

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1979, An experimental translocation of the eastern timber 

wolf, in Klinghammer, Erich, ed., The behavior and ecology 

of wolves: New York, Garland STPM Press, p. 346–419.

Wilson, P.J., Grewal, Sonya, Lawford, I.D., Heal, J.N.M., 

Granacki, A.G., Pennock, David, Theberge, J.B., Theberge, 

M.T., Voigt, D.R., Waddell, Will, Chambers, R.E., Paquet, 

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wolf provide evidence for a common evolutionary history 

independent of the gray wolf: Canadian Journal of Zoology, 

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2009, Genetic characterization of hybrid wolves across 

Ontario: Journal of Heredity, v. 100, suppl. 1, p. S80–S89. 

[Also available at http://dx.doi.org/10.1093/jhered/esp034.]

Wydeven, A.P., Van Deelen, T.R., and Heske, E.J., eds., 2009, 

Recovery of gray wolves in the Great Lakes Region of the 

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212 The History of Patuxent: America’s Wildlife Research Story

Muskrat (Ondatra zibethicus) on water, Patuxent Research Refuge, Laurel, MD, 1980. Photo by Matthew C. Perry, 

U.S. Fish and Wildlife Service.
Other Programs at Patuxent

Wildlife Disease Studies at Patuxent

Glenn H. Olsen

The study of wildlife diseases has always been part of the 

mission of the Patuxent Wildlife Research Center (Patuxent), 

in Laurel, MD. Indeed, when the original lands were being 

chosen and developed, personnel of the U.S. Department of 

Agriculture, Bureau of Animal Industry, Pathological Division, criticized the location of the facility. They believed that 

establishment of a wildlife demonstration and research area by 

the Bureau of Biological Survey in the vicinity of the planned 

Beltsville Agricultural Research Center could lead to a disease 

hazard (Morley, 1948, p. 4). Dr. Leland C. Morley, a veterinarian by training, was the first superintendent of Patuxent 

Research Refuge. Dr. Morley’s appointment and his move into 

the refuge’s first offices (and residence), known as the Log 

Cabin, occurred 7 months before President Franklin D. Roosevelt signed Executive Order No. 7514 on December 16, 1936, 

officially establishing the Patuxent Research Refuge. The Log 

Cabin residence had been acquired by the Federal government 

in April 1936.

The first captive wildlife research flock was established in the spring of 1936, predating the official opening of 

Patuxent. This flock consisted of northern bobwhite (Colinus 

virginianus), which were received from the Section of Disease 

Control of the University of Maryland, demonstrating that the 

cooperative ties between Patuxent and the university date back 

to the earliest days of Patuxent. These quail were used in the 

first experimental work done at Patuxent by biologist Phoebe 

Knappen (Morley, 1948, p. 17), who studied the acceptability and toxicity of various natural seeds and berries that 

were considered at the time to be important quail food. The 

first Patuxent publication about wildlife disease—“Diseases 

of Upland Game Birds (part 5)” by J.E. Shillinger and L.C. 

Morley (1941), published in “Game Breeder and Sportsman”—resulted partly from quail studies. This paper was 

followed by U.S. Fish and Wildlife Service (USFWS) Bulletin 

21, “Diseases of Upland Game Birds,” also by Shillinger and 

Morley (1942).

With the help of the Civilian Conservation Corps (CCC), 

kennels with litter boxes were constructed to house fur-bearing 

animals for disease research. Thirty foxes and an unspecified number of ferrets and mink were acquired for this work 

(Morley, 1948, p. 17). In 1938, Phoebe Knappen and Franklin 

H. May, an employee of the Section of Food Habits of the 

Department of Agriculture, studied the effects of orchard 

sprays on birds (Morley, 1948, p. 29). By this time, a Section of Disease Control had been established at Patuxent, and 

experimental facilities for this section were expanded. Also in 

1938, Dr. Morley hired two additional veterinarians, Dr. Don 

R. Coburn (who started September 21, 1938) and Dr. William H. Armstrong (who started October 17, 1938). In 1942, 

Patuxent published five papers with either Dr. Coburn or Dr. 

Armstrong as the lead author. The subjects of these early 

research papers ranged from Salmonella in muskrats (Ondatra 

zibethicus) (Armstrong, 1942) and chinchillas (Chinchilla sp.) 

(Coburn and others, 1942) to canine distemper in a zoological 

park (Armstrong and Anthony, 1942).

In 1939, funds were requested for construction of a barn 

and greenhouse, but it was decided instead to build a laboratory for Patuxent’s newly named Unit of Disease Investigations. Because the original intent had been to build a barn, the 

architect, Munk Pederson, designed the building to appear 

plain and barn-like. This is why Henshaw Laboratory was set 

into the hillside with a second-story entrance on one side and 

a first-floor entrance on the other. The new building included 

a large greenhouse that was used for other nondisease studies. 

The building remains plain in appearance, with small windows 

and doors, and is more barn-like than Nelson and Merriam 

Laboratories, whose architecture is more ornate (Morley, 

1948, p. 30).

The Unit of Disease Investigations employed the following 

people in the early days of Patuxent:

Personnel Position Dates of employment

William H. Armstrong Veterinarian 10/17/38–8/7/42

Helen M. Churchill Bacteriologist 10/8/42–3/31/45

Don R. Coburn Veterinarian 9/21/38–?

Phoebe Knappen Biologist 7/1/40–6/28/42

Erling Quartrop Veterinarian 4/28/45–6/29/46

Psyche W. Wetmore Bacteriologist 6/1/39–7/23/42

Ralph B. Nestler Biologist 6/1/42–?
214 The History of Patuxent: America’s Wildlife Research Story

Lumber for construction of this building and all early 

buildings, except Merriam Laboratory, came from two sawmills set up on Patuxent property to process trees harvested 

from the site of Cash Lake and downed timber along the 

Patuxent River bottomlands. The Patuxent sawmills were 

so effective that some wood was harvested and shipped to 

Washington, D.C., for construction projects there (Morley, 

1948, p. 33). The sand and gravel used in the cement for all 

construction came from an open gravel pit at Patuxent.

Seventeen papers on wildlife diseases—eight on mammalian wildlife diseases and nine on avian wildlife diseases—were published by Patuxent authors during 1942–49. 

Arnold L. Nelson, Director of the Patuxent Research Refuge, 

described the work of the Wildlife Pathology Laboratory 

in the Bulletin for Medical Research in 1959. He said that 

Patuxent scientists had been working to identify diseases of 

wildlife and the agents causing the diseases, and indicated 

that “Little information exists however, on pathology, significance of disease-causing organisms on the welfare of the host, 

mechanisms of infection and spread, relationship between 

wildlife diseases and environmental stress and methods by 

which an effective attack can be launched to control disease” 

(Nelson, 1959). He described studies of Canada goose (Branta 

canadensis) mortality resulting from gizzard worms at Pea 

Island National Wildlife Refuge in North Carolina. Patuxent 

scientists also were studying diseases of waterfowl, especially 

aspergillosis, the diseases of icteric birds (blackbirds), and the 

relations of stress factors to infectious diseases and parasite 

infestation during the 1950s (Nelson, 1959). Trichomoniasis in 

mourning doves (Zenaida macroura) also was being studied, 

with an emphasis on mode of infection and immunity factors 

(Nelson, 1959).

Nelson acknowledged that the study of mammalian 

diseases was much more limited. He mentioned two ongoing studies, one on the parasites found on mammals at the 

Patuxent Research Refuge and the other on distemper in wild 

mammals (Nelson, 1959). Also at this time, staff at the Walter 

Reed Army Institute of Research in Silver Spring, MD, were 

studying wildlife diseases that were considered zoonotic—that 

is, diseases that spread between animals and humans. This 

work was conducted at Fort George G. Meade Army Post, 

on land that is now part of Patuxent Research Refuge. Patuxent scientists published 36 papers on wildlife diseases in the 

1950s; 15 of these were on mammalian diseases and 21 were 

on avian diseases.

Diseases caused by toxicological agents, namely pesticides, became an area of concern for wildlife populations 

in the 1940s, and Patuxent began studies at that time. The 

program increased in scope under the leadership of Dr. John L. 

Buckley, Patuxent’s director from 1959 until 1963, and was 

renamed the Environmental Contaminants Research Program 

to distinguish it from the study of wildlife diseases caused 

by other agents. More emphasis was placed on statistically 

rigorous controlled experiments. In 1962, the bestselling book 

“Silent Spring” by Rachel Carson (Carson, 1962) highlighted 

this type of threat to wildlife. In 1963, Secretary of the Interior 

Stewart Udall dedicated a new building at Patuxent, named the 

“Biochemistry and Wildlife Pathology Laboratory” to indicate 

its dual role. The building housed state-of-the-art necropsy 

facilities to further the study of wildlife diseases.

The study of lead poisoning in waterfowl also was begun 

in the 1960s. Louis N. Locke and George E. Bagley (1967) 

published the first report from Patuxent on lead poisoning, 

“Coccidioses and lead poisoning in Canada geese,” in the 

journal “Chesapeake Science.” The study of lead toxicity in 

wildlife continued (Heinz, 2016) with more recent work by 

Nimish Vyas, who studied lead poisoning in passerines from 

skeet shooting ranges in the early years of the 21st century 

(Vyas and others, 2000). In 1969, Locke and others (1969) 

published another important lead study that identified lead 

poisoning as a mortality factor in condors. This work was conducted at Patuxent by using captive Andean condors (Vultur 

gryphus) as a surrogate for the endangered California condor 

(Gymnogyps californianus).

Another development in the 1960s that had a large effect 

on wildlife disease studies at Patuxent was the establishment 

of an endangered species research program that included not 

only field research, but captive breeding programs for at least 

eight species, including masked bobwhite (Colinus virginianus 

ridgwayi), bald eagles (Haliaeetus leucocephalus), Mississippi 

sandhill cranes (Grus canadensis pulla), whooping cranes 

(Grus americana), and Puerto Rican parrots (Amazona vittata) 

in addition to the Andean condors.

Also in the 1960s, the role of parasites as disease agents 

in wildlife began to receive greater emphasis in Patuxent 

research (Herman, 1966). Carlton Herman, a parasitologist, 

eventually became leader of the Wildlife Disease Section, as it 

was called in the 1960s–70s. Richard Kocan, another parasitologist, worked on trichomoniasis in mourning doves (Kocan, 

1971), and Barry Tarshis, Herman, and Kocan worked on the 

relation of black flies (Simulium nigricoxum) and leucocytozoon infestations (Tarshis and Herman, 1965; Kocan, 1968a, 

1968b; Kocan and Barrow, 1968; Herman, 1969b).

In the 1960s, Patuxent scientists produced a total of 

67 wildlife-disease-centered publications—52 on avian species, 8 on mammalian species, and 7 on the general topic of 

wildlife disease. Included among these publications is the 

chapter by Herman on “Bird-borne Diseases in Man” (Herman, 1969a) in the first comprehensive veterinary textbook 

on pet birds, “Diseases of Cage and Avian Birds,” edited by 

Margaret L. Petrak (1969). Other notable wildlife disease 

research included work on viruses that cause eastern equine 

encephalitis and myxovirus in deer plus duck viral enteritis 

(duck plague).

The start of the Endangered Species Program caused a 

shift in emphasis in the study of wildlife diseases owing to 

the presence of live animals in pens at Patuxent for long-term 

(10 or more years) rather than periodic (1–3 years) research 

studies. Starting in 1970, a veterinary hospital was located in a 

double-wide trailer on a dead-end road off the loop road in the 

endangered species area. A veterinarian was hired to manage 

the clinical care of the endangered species. James Brown, the 
Other Programs at Patuxent

Wildlife Disease Studies at Patuxent 215

Domestic sheep maintained at Patuxent Wildlife Research Center, Laurel, MD, for disease studies, 1972. Photo by Matthew C. Perry, 

U.S. Fish and Wildlife Service.

first veterinarian to work in this position, was followed by 

James Carpenter, who came in 1975. Louis Sileo (1976–83) 

and Louis Locke worked at the Patuxent environmental contaminants research laboratory. Sileo and others (1983) reported 

on a die-off of captive kestrels at Patuxent attributed to hemorrhagic enteritis and hepatitis.

In 1975, wildlife disease study at Patuxent experienced 

a major shift. A new laboratory to study wildlife diseases, the 

National Wildlife Health Center, was established in Madison, 

WI, as part of the efforts of the USFWS (later U.S. Geological 

Survey [USGS]) to better diagnose and fight disease outbreaks 

at wildlife refuges across the country. Over the next two 

decades, many Patuxent staff members migrated to this new 

laboratory, and general wildlife disease research at Patuxent ended, though research on wildlife diseases caused by 

environmental contaminants and those affecting endangered 

species continued.

In the 1970s, the number of publications fell precipitously as a result of the move of many members of the 

wildlife disease research staff from Patuxent to Madison. 

From 1970 through 1974 (before the move), 38 papers were 

published—33 on avian wildlife disease studies and 5 on 

general wildlife disease subjects. From 1975 through 1979, 

only 13 papers were published—3 on mammalian diseases and 

10 on avian diseases. This decrease in the number of publications on wildlife diseases demonstrates more than anything 

else the shift in program emphasis on wildlife disease research 

away from Patuxent. Wildlife disease publications during 

the 1970s included 43 on avian disease, 3 on mammalian 

disease, and 5 on the general topic of wildlife diseases, for a 

total of 51 papers; however, papers continued to be published 

on trichomoniasis (Kocan, 1971) and plasmodium (Kocan 

and Perry, 1976) infections. Several papers were published 

on avian cholera (Locke and Banks, 1972; Locke and others, 1972). Several publications in the latter half of the 1970s 

Dan Day and Glenn Olsen, U.S. Fish and Wildlife Service, inspecting a 

sandhill crane in the old trailer veterinary hospital at Patuxent Wildlife 

Research Center, Laurel, MD, 1988. Photo by Matthew C. Perry, U.S. Fish and 

Wildlife Service.
216 The History of Patuxent: America’s Wildlife Research Story

Jane Chandler and Glenn Olsen, U.S. 

Geological Survey, inspecting a whooping 

crane in new veterinary hospital at Patuxent 

Wildlife Research Center, Laurel, MD, 1996. 

Photo by U.S. Geological Survey.

about parasites in cranes (Forrester and others, 1978; Carpenter and others, 1979) and endangered black-footed ferrets

(Mustela nigripes) (Carpenter and Novilla, 1977; Carpenter 

and others, 1976) demonstrate the shift toward wildlife disease 

studies involving the captive endangered species colonies 

at Patuxent.

Wildlife disease studies at Patuxent in the 1980s focused 

on two species, whooping cranes and gray wolves (Canis 

lupus). The whooping crane disease research focused on two 

diseases—disseminated visceral coccidiosis, which occurs 

naturally in cranes, but was seen in increased numbers because 

of captive rearing (Carpenter and Novilla, 1980; Carpenter and 

others, 1980; Novilla and others, 1981; Carpenter and others, 1984); and eastern equine encephalitis, which developed 

suddenly in 1984, killing seven whooping cranes (Carpenter and others, 1985; Carpenter and others, 1986; Dein and 

others, 1986). Dr. L. David Mech was hired to manage the 

endangered species Minnesota field station working with gray 

wolves. He was a former graduate student of Durward Allen, 

a Patuxent wildlife research biologist in the 1940s, who had 

moved on to Purdue University of Indiana. Mech, in his wolf 

research, collaborated with Ulysses S. Seal (Veterans Administration Medical Center, Minneapolis, MN) and others about 

disease research and immobilization techniques (Mech and 

others, 1984, 1985, 1986; Kreeger and others, 1987).

Additions to the Patuxent research staff in the 1980s 

included Chris Franson (1979–84), a veterinarian, who worked 

with the environmental contaminants program. Joshua Dein 

(1984–87) joined the Patuxent Endangered Species Program 

as a veterinarian and helped develop the first institutional 

animal care and use committee. When Dein and Franson 

departed to join the staff at the USGS National Wildlife Health 

Center, Glenn H. Olsen was hired (1987–present [2016]) to 

work in clinical veterinary medicine (50 percent) and research 

(50 percent). Beginning in the late 1980s, Olsen and Carpenter 

planned and drafted the blueprints for a new Patuxent Veterinary Hospital that opened on December 3, 1994; it was partly 

funded by Baltimore Gas and Electric Company.

Published papers on wildlife diseases in the 1980s 

totaled 39—25 on avian diseases and 14 on mammalian 

diseases. Patuxent also hired a nutritionist, John A. Serafin 

(1980–82), who worked with the Endangered Species Program 

and published several papers on nutritional diseases (Serafin, 

1981, 1982, 1983).

The 1990s was a decade of changes for Patuxent and 

certainly for wildlife disease research. In 1994, Patuxent 

joined the National Biological Survey and gained several field 

stations. From a wildlife disease standpoint, the most important of these was arguably a former National Park Service field 

station colocated at the University of Rhode Island in Kingston. Howard S. Ginsberg (1994–present [2016]), a medical 

entomologist, joined Patuxent at this field station. In 1990, 

Dr. Carpenter left Patuxent for Kansas State University. In 

1991, Patrice N. Klein (1991–95) was hired as a veterinarian 

to work in pathology and clinical medicine. In October 1996, 

Patuxent joined the USGS. In 1994, a new veterinary hospital 

was opened in a 3,000-square-foot building 0.2 miles west 

of Gabrielson Laboratory. In addition to serving the needs of 

Patuxent’s captive wildlife, the facility has been used for many 

research projects.

Forty-one papers that originated at Patuxent were published on wildlife diseases from 1990 to 1999—19 on avian 

diseases, 9 on mammalian diseases, 12 on general wildlife 

diseases, and 1 on diseases of turtles. During this decade, 

Patuxent initiated a more intensive monitoring and research 

program involving reptiles and amphibians and published one 

paper on shell diseases in turtles (Lovich and others, 1996). 

Other important publications include a paper on mycotoxinrelated epizootic disease in the captive crane colony (Olsen 

Thom Lewis and James Carpenter, U.S. Fish and Wildlife Service, force feed 

with gavage a sandhill crane, Patuxent Wildlife Research Center, Laurel, MD, 

1981. Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.
Other Programs at Patuxent

Wildlife Disease Studies at Patuxent 217

and others, 1995); several papers on Lyme disease; and a 

book, “Ecology and Environmental Management of Lyme 

Disease,” edited by Howard S. Ginsberg (1993). Papers on 

wildlife diseases in endangered species, primarily wolves and 

cranes, continued to predominate, along with those on Lyme 

disease. Several papers were published on new techniques that 

would be used in future programs (Olsen and others, 1990; 

Olsen, 1999). One techniques paper on surgically implanting 

radio transmitters in ducks (Olsen and others, 1992) led to the 

development of an entirely new method of research on duck 

populations, especially far-ranging seaducks (Olsen and others, 2005).

In the first decade of the 21st century, research on 

wildlife diseases continued at Patuxent and at field locations around the world. Since 2005, the veterinary staff has 

been actively involved with implanting platform transmitting 

terminals (PTTs), also called satellite radio transmitters. Most 

of this work has been in support of various projects funded by 

the Sea Duck Joint Venture, a multiagency group supporting 

seaduck conservation, but some work has involved learning more about the habits of seaducks in relation to licensing 

of sites for offshore wind energy. Another important area of 

study with implant and backpack PTTs has been a project on 

avian influenza in Eurasia and Africa, and the potential for this 

disease to be transmitted by migrating waterfowl (Prosser and 

others, 2011).

Another emerging disease of this decade (2000–10) was 

West Nile virus, and Patuxent researchers were active in this 

area, studying the vectors of transmission (Ginsburg, 1993), 

the effect of the virus on endangered species, and possible 

methods for prevention through vaccination (Olsen and 

others, 2009).

Patuxent has had a long and distinguished history of 

research on diseases of wildlife. Although much of the leading role in this area changed owing to the formation of the 

National Wildlife Health Center, Madison, WI, Patuxent still 

(2016) does major investigations dealing with disease, especially in regard to diseases of the Patuxent captive colonies 

of endangered species and other wildlife. Patuxent veterinarians maintain close contact with the veterinarians at the 

Health Center and collaborate on many field studies that focus 

on diseases.

Acknowledgments

The author thanks Dr. Matthew C. Perry (U.S. Geological 

Survey [USGS]) for the opportunity to write this chapter of 

Patuxent history, Lynda J. Garrett (USGS) for help in compiling all 321 of the scientific publications that cover wildlife 

diseases, and Carlyn Caldwell (USGS) for assistance with 

manuscript preparation. 

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cholera in a bald eagle from Ohio: Ohio Journal of Science, 

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Laemmerzahl, A.F., 1996, Prevalence and histopathology 

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Other Programs at Patuxent

Wildlife Disease Studies at Patuxent 219

Mech, LD., Goyal, S.M., Bota, C.N., and Seal, U.S., 1986, 

Canine parvovirus infection in wolves (Canis lupus) from 

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of a severely debilitated wolf: Journal of Wildlife Diseases, 

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Nelson, A.L., 1959, The Patuxent Research Refuge: Bulletin 

for Medical Research, v. 13, no. 1, p. 16–19, 30.

Novilla, M.N., Carpenter, J.W., Spraker, T.R., and Jeffers, 

T.K., 1981, Parental development of eimerian coccidia in 

sandhill and whooping cranes: Journal of Protozoology, 

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Implanting radio transmitters in wintering canvasbacks: 

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and Barnes, S.N., eds., The effects of oil on birds—A multidiscipline symposium: Wilmington, DE, Tri-State Bird 

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game birds (part 5): Game Breeder and Sportsman, v. 46, 

no. 9, p. 170–171, 179.

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Rattner, R.A., and Pattee, O.H., 1983, Hemorrhagic enteritis 

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220 The History of Patuxent: America’s Wildlife Research Story

Red fox (Vulpes vulpes) in pen, Patuxent Research Refuge, Laurel, MD, 1972. Photo by Matthew C. Perry, 

U.S. Fish and Wildlife Service.
Other Programs at Patuxent

Urban Wildlife Research at Patuxent

Lowell W. Adams

Introduction

Urban wildlife research at Patuxent Wildlife Research 

Center (Patuxent) has spanned the last 50 years of Patuxent’s 

80-year history (1936–2016). Urban research dealt with birds, 

mammals, reptiles, invertebrates, wetlands, stream ecology, 

contaminants, diseases, and parasites. The U.S. Fish and Wildlife Service (USFWS) officially established an urban wildlife 

research program in June 1972 (Geis, 1981). The program 

focused on birds and was headed by Dr. Aelred D. Geis at 

Patuxent’s central campus in Laurel, MD. In this chapter, I 

present a review of urban wildlife research conducted by Dr. 

Geis and other investigators at Patuxent’s central campus and 

its various field stations.

Birds

Early research conducted by Dr. Geis dealt with changes 

in the bird community as the planned development of the town 

of Columbia, MD, was underway. From 1966 to 1971, he 

conducted breeding and wintering bird surveys at Town Center 

and in the Village of Wilde Lake (Geis, 1974a, 1974b, 1976). 

During the breeding season, the number of birds of species 

associated with farmland and field habitat declined. Birds in 

this category included northern bobwhite (Colinus virginianus), mourning dove (Zenaida macroura), eastern meadowlark 

(Sturnella magna), red-winged blackbird (Agelaius phoeniceus), and grasshopper sparrow (Ammodramus savannarum). 

Numbers of wood thrush (Hylocichla mustelina) (woodland 

species) and indigo bunting (Passerina cyanea) (edge species) also declined. Birds whose numbers increased during 

this period included northern mockingbird (Mimus polyglottos), chipping sparrow (Spizella passerina), song sparrow 

(Melospiza melodia), European starling (Sturnus vulgaris), 

house sparrow (Passer domesticus), and house wren (Troglodytes aedon). The number of northern cardinals (Cardinalis 

cardinalis) did not change.

In Columbia, housing type affected species composition and bird density (Geis, 1974a, 1974b, 1976). Detached 

houses with lots on which some of the original trees had been 

retained had the most varied species composition. Bird diversity declined in more intensely developed areas characterized 

by townhouses and apartments. Townhouse and apartment 

complexes, however, showed the greatest bird density, consisting mostly of house sparrows and European starlings. Geis 

(1974a, 1974b, 1976) observed that starlings and house sparrows were related to building design and quality of construction. Unboxed eaves provided small openings beneath house 

roofs that birds used for nesting sites (fig. 1), and widely 

louvered air vents and latticework used to camouflage airconditioning units at apartment buildings provided attractive 

nesting sites for starlings and house sparrows.

Also in Columbia, Geis and his colleagues compared two 

methods for counting birds in urban areas (DeGraaf and others, 1991)—point counts and transect counts. They reported 

that transects centered on roads through residential developments and divided into 300- × 300-foot (ft) plots for recording 

data reduced many of the problems associated with counting birds in urban areas, such as varying noise and visibility. 

Figure 1. Bird nest in a house eave, Columbia, MD. Unboxed 

eaves provided small openings beneath house roofs in which 

birds could build nests. Photo by Aelred D. Geis, U.S. Fish and 

Wildlife Service.
222 The History of Patuxent: America’s Wildlife Research Story

Because 80 percent of bird observations were recorded in the 

first 4 minutes of sampling, they concluded that 4 minutes per 

plot was a reasonable time limit (DeGraaf and others, 1991).

Geis (1980a) surveyed breeding and wintering birds 

at Cylburn Park in Baltimore, MD, before construction of 

adjacent Coldspring Town. The 174-acre park was a natural 

area containing a large forest tract in an urban setting. Coldspring Town was planned as a high-density residential area 

(10 dwelling units per acre). In addition to Cylburn Park and 

predevelopment Coldspring Town, Geis (1980a) surveyed a 

nearby mature residential area of detached and two-family 

attached housing with scattered native trees and an abundance 

of mature shrubbery during 1974–76. Buildings ranged from 

25 to 60 years old. Geis (1980a) reported the greatest density 

of birds and the smallest number of species in the mature residential area. In contrast, the mature forest of Cylburn Park had 

the lowest density of birds and the largest number of species 

(33, compared with 22 in the mature residential area).

In the 1970s, Geis addressed questions related to bird 

feeding. He focused research efforts on the seeds birds liked 

to eat and, therefore, the most efficient way for people to feed 

birds. From 1977 to 1979, volunteers recorded more than 

179,000 bird visits and food consumption at experimental 

feeders near their homes (Geis, 1980b; fig. 2). Geis reported 

that the small oil sunflower seed and white proso millet were 

preferred by birds under Maryland conditions. The large, 

black-striped sunflower seed, at the time the traditionally 

used sunflower seed for feeding birds, also was reported to be 

preferred. Many seeds in wild bird mixes sold on the market, 

including wheat, milo, peanut hearts, hulled oats, and rice, 

however, were generally unattractive to birds. Feeding preferences differed by species. Nevertheless, on the basis of Geis’s 

work, oil sunflower and white proso millet became widely 

popular seeds for feeding birds. At the time, oil sunflower 

seeds were not marketed as birdseed. Geis’s work created 

public demand, and he played a role in convincing the seed 

industry to make oil sunflower seeds available as birdseed. 

Geis’s research report was in high demand by the public and 

was distributed widely as a USFWS Special Scientific Report 

(Geis, 1980b).

Patuxent biologists completed some urban bird research 

before establishment of the urban wildlife research program 

mentioned above. Linehan and others (1967) reported early 

results from an ecological study of urban woodlots in Delaware initiated in 1964. These investigators studied birds in 

nine woodlots during the breeding seasons of 1966 and 1967. 

Woodlot sizes ranged from 2 to 36 acres. Fifty-three species were recorded. Of 27 species common in the woodlots, 

only 13 were considered true forest birds. Many were edge 

species that could make use of the considerable amount of 

edge habitat associated with the small woodlots. Linehan and 

others (1967) observed that red-eyed vireo (Vireo olivaceus) 

Figure 2. Bird-feeding station, Howard County, MD, 1980—one of the sites where birdseed was tested. Photo 

by Lowell W. Adams, Urban Wildlife Research Center, Columbia, MD.
Other Programs at Patuxent

Urban Wildlife Research at Patuxent 223

breeding density was positively related to woodlot size. The 

red-eyed vireo was 1 of 21 species later identified by Darr 

and others (1998) and other researchers as an “area-sensitive” 

species whose probability of occurrence increases with the 

size of unfragmented forested areas. Of the 21 principal species recorded in the Delaware urban woodlots, only 4—wood 

thrush, red-eyed vireo, red-bellied woodpecker (Melanerpes 

carolinus), and eastern wood-pewee (Contopus virens)—were 

classified as area sensitive by Darr and others (1998). The 

small Delaware woodlots lacked woodland warblers and 

tanagers, along with vireos and other forest interior species 

that require larger forested tracts to breed and nest successfully. Nevertheless, the Delaware urban woodlots provided 

habitat for many birds. Linehan and others (1967) concluded, 

“Very dense populations of a large variety of breeding birds 

are found in urban woodlots of 20 or more acres which have 

adequate shrub understory, mature and dead standing trees, 

and vegetative edge types that are of sufficient width and 

proper quality.” Results of additional work conducted in 

Delaware urban-suburban woodlots were reported by Jones 

and others (1966), Longcore and others (1966), and West and 

others (1966).

Patuxent researchers studied a black-crowned night 

heron (Nycticorax nycticorax) nesting colony in the Patapsco 

River estuary of Baltimore Harbor, MD, during May–July 

1988 (Erwin and others, 1990, 1991). The colony consisted of 

more than 300 nesting pairs, and researchers were interested 

in determining whether or not birds avoided using contaminated areas of the urban estuarine environment as feeding 

sites. Flight directions of birds from the nesting colony were 

documented, and some birds were followed with aircraft and 

small boats. More birds appeared to fly west and northwest 

toward Baltimore than to other areas when leaving the colony 

on foraging flights, although results were not statistically significant. Areas west and north of the nesting colony were more 

heavily developed than areas to the east and south. Researchers speculated that city lights might have attracted small fish, 

crabs, and invertebrates, which, in turn, attracted the herons. 

Black-crowned night herons that feed in contaminated urbansuburban environments may not as a result experience direct 

threats to their survival or reproductive success (Rattner and 

others, 2000), but access to high-quality, uncontaminated 

wetlands with a large prey base probably could better sustain 

colonial wading bird populations.

Sparling and others (2007) studied nesting success and 

foraging behavior of red-winged blackbirds in stormwater 

wetlands in metropolitan areas. Such wetlands are constructed 

to manage stormwater runoff from developed sites following rain events. Controlling stormwater is required by law in 

many jurisdictions. Sparling and his colleagues focused on 

stormwater retention wetlands draining residential, commercial, and highway sites. These investigators studied birds 

at 12 stormwater retention wetlands in Prince George’s, 

Howard, and Anne Arundel Counties, MD, during 1993–94. 

They noted no significant differences in nest success among 

the wetland types. Number of nests was positively correlated 

with percent of area occupied by cattail (Typha spp.), and nest 

success and foraging rates were similar to those reported for 

natural wetlands. Forty-seven species of birds were recorded, 

and investigators concluded that stormwater wetlands could 

provide suitable habitat for red-winged blackbirds and perhaps 

other species. Although constructed for stormwater control, 

wetland features can be designed to either attract or discourage 

wildlife use. Such features include size and shape of the wetland, side slope (steep or shallow), water depth, and percent of 

area occupied by cattails.

Monitoring wetland contaminants, particularly zinc and 

copper, in stormwater wetlands would provide more information about potential problems with contaminants. In a related 

study of the same sites, Sparling and others (2004) focused 

on contaminant exposure of nestling red-winged blackbirds. 

Investigators reported elevated concentrations of zinc and copper in wetland sediments and carcasses of 8-day-old chicks. 

Sediment zinc concentrations were negatively correlated with 

average red-winged blackbird clutch size, hatching success, 

fledgling success, and nest success. Overall, however, nest 

success was comparable to national averages. Additional study 

of this issue could yield important information that could be 

used to help educate the public about the benefits of controlling sedimentation rates and prevent wetland areas from 

becoming toxic sinks to wildlife.

Patuxent researchers also have studied the effect of 

urban light on birds. On the Hawaiian Island of Kauai, more 

than 1,000 fledgling seabirds of three species were attracted 

to coastal lights during autumn flights to the ocean (Telfer 

and others, 1987). All three species are either threatened or 

endangered. The birds, apparently on their first flight to the 

ocean, became disoriented and crashed into buildings, wires, 

vehicles, and other structures. The phenomenon has increased 

since the early 1960s as urban areas have grown and the 

number of high-intensity lights has increased. From 1978 to 

1985, 11,767 Newell’s shearwaters (Puffinus auricularis 

newelli), 38 dark-rumped petrels (Pterodroma phaeopygia 

sandwichensis), and 8 band-rumped storm-petrels (Oceanodroma castro cryptoleucura) were found downed—that is, 

either dead (8.6 percent) or still alive, but injured or stunned 

on the ground, unable to fly. The anomaly was most severe at 

river mouths near urban coastal areas. Apparently, young birds 

followed rivers from inland nesting grounds to the sea and 

became disoriented because of urban lights along the coast. 

Through a program established with public cooperation and 

government-run “aid stations,” 90 percent of the downed birds 

were returned to the wild. Telfer and his colleagues reported 

that light shielding can reduce the problem, and some resort 

owners were convinced to turn off some of their decorative 

lights during the most critical period.

Other researchers at Patuxent described methodologies 

for reporting bird species richness and community structure. 

Using Breeding Bird Survey data (Sauer and others, 1997), 

Cam and others (2000) found significant negative correlations between bird species richness and urban land use in 

six physiographic regions of the Mid-Atlantic States (fig. 3). 
224 The History of Patuxent: America’s Wildlife Research Story

0.54

0.56

0.52

0.50

0.48

0.46

0.44

0.42

0.40

0.38

0.36

0.34

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Estimate of relative species richness

Proportion of urban land

EXPLANATION

Physiographic region

Upper Coastal Plain

Northern Piedmont

Southern Piedmont

Ridge and Valley

Ohio Hills

Allegheny Plateau

Figure 3. Relation between relative species richness and proportion of urban land (arcsine square-root transformed) 

by physiographic region. Relations were estimated by using a model. (Modified from Cam and others, 2000)

These investigators pointed out that local species richness 

may be affected by local and regional factors. They presented 

a method to estimate relative species richness that accounts 

for potential variation in species detection probability and 

allows flexibility in specification of a reference community. 

For example, it is not likely that all species are detected during 

sampling sessions. The defined species list ideally is derived 

from regional data, they noted, and a smaller regional pool 

might help to account for fewer species at a site.

Research at Patuxent has yielded conclusions about 

planning for and management of urban and urbanizing areas 

(Leedy and Geis, 1980; Geis 1986a, 1986b). Geis (1986a) 

reviewed the early history of the development of the planned 

community of Columbia, MD. In 1965, county zoning called 

for a minimum of 20 percent open space, a minimum of 15 

percent low-density residential housing, and a maximum of 

10 percent attached housing. Zoning was changed in 1973 to 

require a minimum of 30 percent open space, a minimum of 

12 percent low-density residential housing, and a maximum 

of 12 percent attached housing. Less than a decade later, 

these regulations were changed again to require a minimum 

of 36 percent open space and a minimum of 10 percent lowdensity residential housing. Although these zoning changes 

were prompted by changes in housing demand, they also had 

ecological benefits. Geis (1986a) noted that many trees were 

preserved during development and that many more trees and 

shrubs were planted following development. In addition, the 

water areas (three lakes and many ponds) that were created 

benefited wildlife. These characteristics plus the large amount 

of open space retained after development were considered 

positive for wildlife populations. Geis (1986a) noted, however, 

that originally there was no plan to manage open space. It 

was simply mowed on a regular basis (fig. 4), providing little 

Figure 4. Early residential development and open space in 

Columbia, MD. Geis (1986b) noted that open space could be 

managed to enhance wildlife habitat and public wildlife viewing 

opportunities. Photo by Aelred D. Geis, U.S. Fish and Wildlife 

Service.

wildlife habitat. He suggested that the open space could be 

managed to enhance both wildlife habitat and public wildlife 

viewing opportunities. He also noted that building design and 

construction characteristics in some areas allowed populations 

of European starlings, house sparrows, and common pigeons 

(Columba livia) to increase, often causing nuisance situations 

for residents.

Geis (1986b) pointed out that the amount of woody 

vegetation retained during development and planted after 
Other Programs at Patuxent

Urban Wildlife Research at Patuxent 225

development was the most important factor for the well-being 

of birds in Columbia. In Europe, he noted, although many 

areas are intensively manicured near buildings, a hedge is 

used to separate these areas from less intensively managed 

areas that are infrequently mowed. He argued that managing 

open space to include meadow habitat and reduce the amount 

of regular mowing would provide better habitat that could be 

beneficial to bird populations.

Obrecht and others (1991) described a 1960 agreement 

between the USFWS and Potomac Electric Power Company 

(Washington, D.C.) for managing vegetation on a newly 

constructed electric transmission line right-of-way through 

the Patuxent property. A diverse shrub community that was 

allowed to develop on the right-of-way after construction provided habitat for wildlife. Management consisted of periodic 

removal of tall-growing tree species to avoid conflict with 

the overhead electric transmission lines, which was accomplished by selectively applying herbicide to the stems of each 

unwanted plant. The site effectively showed how right-of-way 

management can benefit wildlife in metropolitan areas.

Darr and others (1998) used forest breeding bird data in 

combination with county zoning and a woodland conservation 

ordinance to develop a forest conservation plan for the watershed of the Western Branch of the Patuxent River in Prince 

George’s County, MD. These investigators were interested 

in developing a forest conservation plan that would benefit 

area-sensitive forest breeding birds that require large tracts of 

forest for successful nesting. Breeding birds were surveyed 

during the nesting seasons (late May–early July) of 1992 to 

1994. Forest tracts were catalogued into seven size classes that 

ranged from 1.2 to 5 acres to greater than 1,236 acres. Twentyone of the 100 bird species recorded were determined to be 

area sensitive. The researchers identified 22 forest tracts of 

a size that likely would support successfully nesting populations of area-sensitive birds and indicated that giving these 

areas priority for conservation efforts could have a desirable 

benefit. They concluded, “The resulting conservation plan 

will maintain and enhance breeding habitat for area-sensitive 

forest birds, while still allowing for additional development as 

human populations increase.”

In the southern Piedmont Physiographic Province of 

the southeastern United States, human population growth 

was leading to increased conversion of rural, forested, and 

agricultural lands to urban and suburban areas. Conroy and 

others (2003) argued that this process leads to loss of “natural capital” in the form of biological diversity and ecosystem 

function. Although the resilience of ecosystems decreases with 

increasing human effects on the systems, humans evolved in 

these ecosystems and are dependent on them for sustaining 

human life. Conroy and others (2003) suggested that incorporating the concept of ecosystem and landscape resilience into 

the landscape-level decision-making process could lead to 

more effective decision making in the future. To incorporate 

this concept, the economic value of ecosystem services would 

need to be determined and factored into landscape-level urban 

and suburban planning. 

Mammals

High white-tailed deer (Odocoileus virginianus) densities 

in many metropolitan areas throughout the United States have 

created human-deer conflict situations (Rudolph and others, 

2000). Wildlife researchers have studied nonlethal methods 

of controlling urban deer density, and Dr. Brian Underwood 

of Patuxent’s field station at the State University of New York 

College of Environmental Science and Forestry, Syracuse, has 

been involved with some of that work. He was a member of a 

team that evaluated immunocontraception for managing suburban white-tailed deer in Irondequoit, NY (a suburb of Rochester). During 1995–98, the team studied efforts required to treat 

female deer and assessed the utility of using immunocontraception to control growth of the deer population. The researchers reported that the effort to capture and mark deer and to 

administer follow-up treatment remotely with a dart gun was 

inversely related to deer density (Rudolph and others, 2000). 

Some deer were difficult to approach for treatment. Dr. Underwood and his colleagues concluded that the technique had the 

potential to hold suburban deer populations between 30 and 70 

percent of ecological carrying capacity. This technique could 

be useful in localized populations where treatment involves 

100 or fewer deer out of a total population of 200 or fewer 

animals (Rudolph and others, 2000).

Follow-up research in Irondequoit from 1997 to 2000 

focused on using immunocontraception for managing deer 

on a local scale (2–4 square miles) (Porter and others, 2004). 

These investigators studied females only and reported that 

deer showed strong site fidelity. Annual survival was 64 percent, and the major cause of mortality was deer-vehicle collisions. Dispersal rates were less than 15 percent for yearling 

and adult deer. The study supported the idea of localized, 

neighborhood-scale management because of high site fidelity, 

as well as small home-range sizes and limited seasonal movement of the deer.

Reptiles

Ferebee and Henry (2008) studied the movement and distribution of the eastern box turtle (Terrapene carolina) in Rock 

Creek Park, Washington, D.C. The park is surrounded almost 

entirely by urban development and, at 1,754 acres, is one of 

the largest national parks in a major city in the United States. 

These investigators focused their work within a 37.6-acre 

study area in the northern section of the park during 2001–04. 

The population density of turtles (2.42–4.02 turtles per acre) 

was low when compared with that in nearby areas of Patuxent (20.75–22.25 turtles per acre) and Mason Neck National 

Wildlife Refuge, VA (25.62 turtles per acre). In Rock Creek 

Park, males outnumbered females 5.3:1. The researchers found 

no significant evidence of natural recruitment. The old-age 

structure, low recruitment, low productivity, low population 

density, removal as pets, and high potential for substantial 
226 The History of Patuxent: America’s Wildlife Research Story

road mortality, particularly for females, led these investigators 

to conclude that long-term survival of box turtles in the park 

was uncertain.

Invertebrates

Aliberti Lubertazzi and Ginsberg (2010) studied dragonfly diversity (Aeshnidae, Corduliidae, Gomphidae, and 

Libellulidae) at small wetlands along an urbanization gradient 

in Rhode Island. These investigators reported that diversity, 

species richness, and evenness did not change along the gradient, although relatively rare species generally were found at 

the rural end of the gradient.

Wetlands

Wetlands are important habitats for many wildlife species 

and provide other benefits, including groundwater recharge, 

flood storage, sediment retention, and water-quality enhancement. Unfortunately, by the mid-1980s in the 48 conterminous 

States of the United States, urbanization had caused the loss of 

22 percent of saltwater wetlands and 6 percent of freshwater 

wetlands (Guntenspergen and Dunn, 1998). Many wetlands 

that had not been destroyed were altered and degraded. The 

distribution of water within the hydrologic cycle typically was 

altered with land development.

Syphax and Hammerschlag (1995) summarized the 

first efforts to restore freshwater tidal marshes in the Anacostia River of Washington, D.C. Tidal marshes historically 

were common along the river, and annual wildrice (Zizania 

aquatica L.) and other wetland plants were abundant. During the 1920s to 1940s, the U.S. Army Corps of Engineers 

dredged and channeled the Anacostia River from the Potomac 

River to Bladensburg, MD, to improve navigation. In 1940, 

the marshes at Kenilworth were dredged.

Reconstruction of 32 acres of emergent wetlands of 

the old Kenilworth marshes began in October 1992 with the 

addition of fill material to create a gradient of moist soils and 

water depth. Tidal channels were cut that approximated the 

original channels. In May 1993, 16 local native plant species 

were introduced. Hammerschlag and Krafft (2006) reported 

on 5 years of post-reconstruction monitoring of the 67-acre 

Kingman Marsh, one of four reconstructed wetlands of the 

Anacostia River. Vegetation establishment was initially strong 

but declined with grazing pressure from resident Canada geese 

(Branta canadensis). By 2004, only two of seven planted species remained. Efforts to control the size of the goose population by nonlethal means were unsuccessful.

A similar effect of resident Canada goose grazing on 

wetland plants was noted along the tidal marshes of the 

upper Patuxent River at Jug Bay near Upper Marlboro, MD 

(Haramis and Kearns, 2007). Through experimental use of 

fenced exclosures during 1999–2004, these investigators 

demonstrated striking growth of annual wildrice in areas 

where geese were denied access. Consequently, a goose reduction plan was implemented by addling eggs to reduce recruitment and opening areas to Maryland’s September resident 

goose-hunting season to reduce population size. Approximately 1,700 geese were harvested during a 4-year period. 

These actions, along with fencing and planting, resulted in 

dramatic restoration of annual wildrice and other vegetation 

along a 6-mile- (mi) long section of the upper Patuxent River.

Stream Ecology 

Research ecologist Dr. Mary Freeman, based at Patuxent’s field station at the University of Georgia in Athens, was 

a member of a research team studying effects of urbanization 

on small streams of the Piedmont Physiographic Province of 

north-central Georgia near Atlanta. One of the team’s first publications focused on habitat quality and fish assemblages along 

an urbanization gradient (Walters and others, 2005). Field 

work was conducted during 1999–2000. Fish-species richness 

and density declined with increased urbanization. Centrachids, 

largely species of bass and sunfish that were more resistant 

to disturbance, became dominant, and other species declined 

or were locally extirpated. The number of endemic species as 

a group declined with increasing urbanization. The researchers concluded that human disturbance might cause major 

changes in species composition despite only minor changes in 

species richness. 

Also early in its work, the team investigated the function of riparian forests as stream protection buffers in urban 

and suburban areas at a relatively small scale (Roy and others, 

2005a). The unit of measurement was the “reach scale,” a 

650-ft length of stream. The researchers studied five small 

streams during 2001–03. Streams with riparian forest had 

greater channel width and contained more large woody debris 

than streams without riparian forest (open streams), which had 

more algae; contained more tolerant fish and habitat generalists, such as largescale stoneroller (Campostoma oligolepis) 

and southern studfish (Fundulus stellifer); and had greater 

herbivore density and size. Catchment-scale (watershed level) 

land cover may have important effects on fish communities, and reach-scale studies do not detect catchment-scale 

effects. Roy and his colleagues concluded that preservation of 

forested riparian fragments alone may not adequately protect 

stream ecosystems.

 The Georgia research team also investigated effects of 

hydrologic alterations on stream fish assemblages (Roy and 

others, 2005b). Three land-cover categories based on degree 

of ground-surface imperviousness (less than 10 percent, 10–20 

percent, and greater than 20 percent), with increasing imperviousness representing increasing urbanization, were studied. 

Altered stormflows in summer and autumn were related to 

decreased richness of endemic, cosmopolitan, and sensitive 

fish species. Hydrologic variables explained 22 to 66 percent 
Other Programs at Patuxent

Urban Wildlife Research at Patuxent 227

of the variation in fish-species richness and abundance. The 

researchers concluded that use of more porous pavement (for 

roads and parking lots), rain gardens, and drainage swales 

would increase infiltration and minimize alteration to stream 

ecosystems.

Additional research in Georgia documented that stream 

hydrology and sedimentation affect the ability of riparian 

forests to maintain healthy stream ecosystems in urban catchments. Roy and others (2006) reported that excessive sedimentation in streams was detrimental to sensitive specialist species, and, where such conditions prevailed, forest cover along 

the stream would not protect the species. The Cherokee darter 

(Etheostoma scotti), a sensitive species that was on the Federal 

list of threatened species, was not found in the study streams 

that exhibited the most stormflow alteration. Maintenance of 

the Cherokee darter most likely will require management of 

both stormflow alteration and sedimentation loads (Roy and 

others, 2006). In the north-central Georgia study area, these 

processes were driven largely by urbanization in the catchment. Riparian forests were important but were not sufficient 

to protect streams in highly urbanized catchments. Percent forest cover was important at the 0.6-mi stream-length scale only 

if urbanization was less than 15 percent of the catchment area 

(Roy and others, 2007). Forest cover at the reach scale (650 ft 

of stream length) had no effect on fish assemblages. The most 

sensitive fish species became rare when the level of impervious cover (as a measure of urbanization) reached 2 percent 

(Wenger and others, 2008).

Urbanization is accompanied by road construction, and 

roads can alter stream ecosystems. The design of culverts 

constructed where roads cross over streams greatly affects fish 

assemblages. Norman and others (2009) reported that, of the 

culverts tested, the bottomless box culvert appeared to allow 

unrestricted movement for benthic and water-column fishes. 

The three-barrel pipe culvert and the box culvert with a bottom 

restricted fish movement.

On the basis of their research, the Georgia team reviewed 

the effectiveness of measures for managing aquatic species as 

areas are urbanized (Wenger and others, 2010). This information was useful in the development of the Etowah Habitat 

Conservation Plan (HCP) (Etowah HCP Advisory Committee, 

2007) for three federally protected fish species in the area—

the Etowah darter (Etheostoma etowahae), Cherokee darter 

(Etheostoma scotti), and amber darter (Percina antesella). 

The plan included a management policy to address the effects 

of stormwater runoff and other stressors, and an adaptive 

management strategy to incorporate new data over time and 

to adjust management policies on the basis of the new data. 

Wenger and others (2010) predicted that use of the HCP 

offered a high probability of long-term persistence of the three 

fish species.

Other Patuxent researchers have studied the effects of 

urbanization on fish communities in coastal New England 

streams (Coles and others, 2004). These investigators found 

that cyprinids (minnows) and centrarchids (sunfish) were the 

dominant taxa. Cyprinid richness decreased with increasing 

urban development, but no clear urban effect was noted for 

centrarchids. Contaminant-tolerant species, such as white 

sucker (Catostomus commersonii), blacknose dace (Rhinichthys atratulus), and bluegill (Lepomis macrochirus), were 

fairly widespread and indicated no strong association with 

degree of urban development.

Diseases and Parasites

Louis Locke, a histopathologist at Patuxent, reviewed diseases and parasites of urban wildlife at an urban wildlife symposium in 1973 (Locke, 1974). He discussed diseases affecting 

only wildlife species, such as pox, trichomoniasis, salmonellosis, canine distemper, and Type C botulism, as well as diseases 

with public-health implications. Included in the latter category 

were histoplasmosis, cryptococcasis, rabies, and arboviruses, 

such as eastern, western, and St. Louis encephalitis.

Patuxent investigators at field stations in New York 

studied the distribution and abundance of West Nile and 

eastern equine encephalomyelitis virus vectors (mosquitoes) 

in Suffolk County in relation to human population density 

and land-use/land-cover patterns (Rochlin and others, 2008). 

Land-use/land-cover information was obtained from aerial 

orthophotographs supplied by Suffolk County (2001). Areas 

were categorized as residential, natural, barren, or saltwater. 

The researchers reported that land-use/land-cover information provided more accurate spatial resolution and was more 

useful than human population density in describing mosquito 

distribution patterns.

Summary

Patuxent Wildlife Research Center (Patuxent) biologists have contributed to an improved understanding of urban 

wildlife ecology, conservation, and management. The urban 

wildlife research program established at Patuxent in 1972 was 

headed by Dr. Aelred D. Geis. Early in his program, Geis studied the relation between bird habitat factors and development 

of the new town of Columbia, MD, and documented changes 

in bird communities as urbanization advanced. He determined 

that population numbers of farmland and field species, such as 

northern bobwhite, mourning dove, eastern meadowlark, redwinged blackbird, and grasshopper sparrow, declined, whereas 

population numbers of other species, such as northern mockingbird, chipping sparrow, song sparrow, European starling, 

house sparrow, and house wren, increased with development. 

His results showed that building design and construction 

features affected the density of so-called nuisance birds such 

as house sparrows and European starlings. Later, Geis studied 

supplemental bird feeding by people and found that the small 

oil sunflower seed and white proso millet were preferred by 

birds under Maryland conditions. At the time (late 1970s), oil 

sunflower seeds were not marketed as birdseed. Geis’s work 
228 The History of Patuxent: America’s Wildlife Research Story

created public demand and helped convince the seed industry 

to make oil sunflower seeds available as birdseed. Additional 

urban bird-related research by other investigators at Patuxent included work on the effects of habitat fragmentation on 

area-sensitive species and effects of contaminants and artificial 

light on birds.

Results of studies by Geis and other Patuxent scientists 

helped guide planners and managers of urban and urbanizing 

areas by showing that trees and shrubs preserved or planted 

in urban open spaces, along riparian areas of streams, and 

within watersheds are valuable for wildlife. Geis’s work in 

the Columbia study area showed that reduced mowing and 

increased creation of meadow habitat in urban open space 

would increase both the availability of wildlife habitat and 

public wildlife viewing opportunities.

Urban wildlife-related research at Patuxent included 

investigations of nonlethal methods of controlling white-tailed 

deer density in metropolitan areas; movement and distribution of the eastern box turtle in Rock Creek Park, Washington, D.C.; dragonfly diversity at small wetlands along an 

urbanization gradient; and diseases and parasites of urban 

wildlife. Research efforts also focused on wetland restoration in metropolitan Washington, D.C., and stream ecology in 

north-central Georgia near the State’s expanding capital city of 

Atlanta. Patuxent’s location in the Baltimore-Washington metropolitan area facilitates its continuing study of urban wildlife, 

as well as potential future collaborations with researchers at 

nearby universities.

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Other Programs at Patuxent

Patuxent Research Refuge—Supporting Wildlife Science

Bradley A. Knudsen

Patuxent Research Refuge in Laurel, MD, was established by President Franklin D. Roosevelt through Executive 

Order 7514, dated December 17, 1936. This Order clearly 

expressed the purpose of the refuge—“...to effectuate further the purposes of the Migratory Bird Conservation Act...

reserved and set apart...as a wildlife experiment and research 

refuge.” Since 1936, Patuxent Research Refuge has amassed a 

myriad of purposes through various land acquisition authorities or additional Executive Orders—for example, “for use as 

an inviolate sanctuary, or for any other management purpose, 

for migratory birds” (16 U.S.C. 715d, Migratory Bird Conservation Act of 1929), and “...recreation, conservation, wildlife 

preservation, and related scientific and educational activities” 

(Executive Order 11724, June 27, 1973).

The original research purpose remains the primary 

purpose of the refuge and is applied to any lands added 

to the refuge since its initial establishment. This purpose 

remains unique within the National Wildlife Refuge System. 

The purpose of many refuges is to provide habitat to benefit 

migratory birds. Other refuges, such as Horicon National 

Wildlife Refuge in Wisconsin, have a unique purpose—“to 

provide habitat for redhead ducks” (http://www.fws.gov/

refuge/Horicon/about.html, accessed June 19, 2015). Patuxent 

Research Refuge’s purpose is to support the critical function 

of wildlife research (http://www.fws.gov/refuge/Patuxent/

about.html, accessed June 19, 2015).

Two long-time employees offered interesting perspectives on Patuxent Research Refuge and its ability to provide 

opportunities for wildlife research. Retired refuge biologist 

Holliday Obrecht, a scientist for nearly 30 years, often said 

that the refuge rarely had to turn away a research request 

because of the variety of habitats the refuge had to offer 

(Holliday Obrecht, U.S. Fish and Wildlife Service, oral commun., 2012). Retired wildlife research scientist Dr. Chandler 

Robbins, in a recent video production, “History of Patuxent” 

(U.S. Geological Survey, 2011), which highlights the history 

of Patuxent, says, “It was Gabrielson’s dream [referring to 

Dr. Ira Gabrielson, who was instrumental in the establishment of Patuxent Research Refuge] to maintain a variety of 

habitats to conduct research...” Other speakers who appear 

on the video include Susan Haseltine, Gary H. Heinz, Kathy 

O’Malley, Matthew Perry, Chandler Robbins, and Gregory 

Smith of the U.S. Geological Survey (USGS), and Bradley A. 

Knudsen and Frank McGilvrey of the U.S. Fish and Wildlife 

Service (USFWS).

Trends in the quantity and type of research conducted at 

Patuxent Research Refuge over the years are shown in figure 1 

and table 1, respectively. Much of the research, particularly 

the decades-long research that has been so critical in documenting habitat and wildlife change over time, has, of course, 

been conducted by employees stationed at Patuxent Research 

Refuge. The refuge, however, also has provided research 

opportunities for nonstaff researchers (universities, State 

agencies, county environmental managers, and others) on this 

12,841-acre “outdoor laboratory” for decades. Since 2000, 

nonstaff research projects have actually outnumbered projects 

conducted by staff members.

The variety of flora and fauna studied is equally extensive. Birds certainly have been a focal point, but insects, 

pollinators, reptiles and amphibians, mammals, fish, fungi, and 

bacteria have all been included in the multitude of research 

subjects addressed at Patuxent Research Refuge during the 

past more than 75 years (1940–2016). The disciplines of 

population modeling, habitat management, endangered species 

propagation, toxicology, wildlife and human disease transmission, and environmental threats (habitat fragmentation, acid 

rain, water quality) have all been topics of past and ongoing 

research at Patuxent Research Refuge.

In What Other Ways Does Patuxent 

Research Refuge Support Wildlife 

Research?

• As mentioned above, the refuge encompasses more 

than 12,800 acres of federally protected land that can 

be available for research studies, both short- and longterm, essentially for the foreseeable future.

• The refuge provides a secure land base with law 

enforcement personnel who offer protection and security for the many captive animal colonies housed on 

the property.
232 The History of Patuxent: America’s Wildlife Research Story

* **

1930 1940 1950 1960 1970 1980 1990 2000 2010

0

5

10

15

20

25

30

35

Year

Number of research projects

Figure 1. Number of U.S. Fish and Wildlife Service/U.S. Geological Survey research projects conducted by researchers at Patuxent 

Research Refuge, Laurel, MD, 1936–2010. (*, missing data)

Table 1. Earliest and longest running research at Patuxent Research Refuge, Laurel, MD.

Date Researcher(s) Research subject Reference

Earliest

1936–42 Stewart and Robbins Winter and breeding bird abundance and distribution Stewart and others, 1952

1936 Hotchkiss and Stewart Vegetation of Patuxent Research Refuge Hotchkiss and Stewart, 1947

1936 Armstrong Fur animal autopsies None

Longest running

70 years Stewart and Robbins Christmas bird counts Robbins, 1966

40 years Stewart/Henny/Martin Red-shouldered hawk (Buteo lineatus) nest survey and 

population ecology

Stewart, 1949; Henny and 

others, 1973; Martin, 2004

40 years Uhler/McGilvrey/Haramis/Obrecht Wood duck (Aix sponsa) box management and research Perry and others, 2000

38 years Stickel/Hall/Henry Eastern box turtle (Terrapene carolina) surveys Henry, 2003

32 years Bystrak/Dawson Mist netting birds for banding None

30 years Martin Butterfly surveys of Central Tract (location of most 

research study sites; generally closed to the public)

None
Other Programs at Patuxent

Patuxent Research Refuge—Supporting Wildlife Science 233

• The refuge offers a variety of public uses—hunting, 

fishing, wildlife observation, environmental education, 

and interpretation programs— that minimize disturbance to research projects. Its Central Tract, where the 

bulk of the research is conducted, is closed to public 

use, except on a few days in the fall when a controlled 

deer-management hunt is held.

• The National Wildlife Visitor Center in the refuge 

(fig. 2) is a 40,000-square-foot public facility that 

presents high-quality exhibits on wildlife research, 

natural-resource problems, and wildlife conservation. 

It also offers meeting space for science seminars and 

workshops for as many as 250 participants.

• The refuge provides office space for the USFWS Division of Migratory Bird Management. Colocation of 

this group allows for scientific information exchange 

and collaboration on a variety of wildlife-related needs.

• The refuge supports a large volunteer program of as 

many as 250 participants annually, many of whom 

become advocates for the refuge in particular and 

natural resources in general. Volunteers provide critical 

support for outreach events and assist with some of the 

research projects, thereby enhancing and increasing 

research capability.

Figure 2. Visitor Center facing Lake Redington, Patuxent 

Research Refuge, Laurel, MD, 1994. Photo by Matthew C. Perry, 

U.S. Geological Survey.

• Through environmental education and interpretation 

programs, each year thousands of students are exposed 

to the wonders of nature and the importance of the 

outdoors. It is not unreasonable to hope that their 

participation has helped nurture a conservation ethic in 

at least some of these young people, and perhaps has 

inspired some of them to go on in life to become the 

next Chan Robbins, Ira Gabrielson, or Rachel Carson.

Dedication of the first and largest fishing pier accessible to persons with disabilities at Patuxent Research Refuge, Laurel, MD, 

1992 (left to right: Patuxent Director Harold O’Connor, Prince George’s County Executive Parris Glendenning, U.S. Representative 

Steny Hoyer, and Facility Manager Bill Lomax). Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.
234 The History of Patuxent: America’s Wildlife Research Story

A Memorandum of Agreement (MOA) between the 

USFWS and the USGS, signed by the respective directors of 

these agencies in September 2000, dealt primarily with the 

shared responsibilities for operations and maintenance of the 

substantial infrastructure at Patuxent; however, an important 

part of this MOA addressed the furthering of and recommitment to Patuxent’s research purpose. The MOA described 

the concept of priority research, defined as “...projects...

important to DOI [Department of the Interior], the FWS [U.S. 

Fish and Wildife Service], the NWRS [National Wildlife 

Refuge System], and/or State Fish and Game agencies, and...

address important management issues/techniques, and species 

of concern...,” and emphasized the importance of conducting 

such priority research at the Patuxent Research Refuge and the 

Patuxent Wildlife Research Center located on the refuge.

This commitment ensures that research will continue to 

be an essential part of the refuge’s future and reaffirms the 

facility’s research purpose. Former Patuxent Wildlife Research 

Center Director Harold J. O’Connor used to say, “Patuxent 

Wildlife Research Center is the research part of Patuxent 

Research Refuge” (Harold O’Connor, U.S. Geological Survey, 

oral commun., 1994). I would add the following companion 

statement: Although the nature of research may change over 

time, research on nature will always be timely.

References Cited

Henny, C.J., Schmid, F.C., Martin, E.M., and Hood, L.L., 

1973, Territorial behavior, pesticides, and the population 

ecology of red-shouldered hawks in central Maryland, 

1943–1971: Ecology, v. 54, no. 3, p. 545–554. [Also available at http://dx.doi.org/10.2307/1935339.]

Henry, P.F.P., 2003, The eastern box turtle at the Patuxent 

Wildlife Research Center 1940s to the present—Another 

view: Experimental Gerontology, v. 38, no. 7, p. 773–776. 

[Also available at http://dx.doi.org/10.1016/S0531-

5565(03)00107-4.]

Hotchkiss, Neil, and Stewart, R.E., 1947, Vegetation of the 

Patuxent Research Refuge, Maryland: American Midland 

Naturalist, v. 38, no. 1, p. 1–75. [Also available at http://

dx.doi.org/10.2307/2421630.]

Martin, E.M., 2004, Decreases in a population of red-shouldered hawks nesting in central Maryland: Journal of Raptor 

Research, v. 38, no. 4, p. 312–319. [Also available at https://

www.researchgate.net/publication/266297424_Decreases_

in_a_population_of_Red-Shouldered_Hawks_nesting_in_

central_Maryland.]

Perry, M.C., Kangas, Partick, and Obrecht, H.H., III., 2000, 

Creating and managing wetland impoundments to provide 

habitat for aquatic birds, in Comin, F.A., Herrera, J.A., and 

Ramirez. J., eds., Limnology and aquatic birds monitoring, modelling and management: Universidad Autonoma 

de Yucatan, International Symposium on Limnology and 

Aquatic Birds, Monitoring, Modelling, and Management, 

2nd, Merida, Mexico, November 24–27, 1997, p. 261–279.

Robbins, C.S., 1966, The Christmas count, in Stefferud, 

Alfred, and Nelson, A.L., eds., Birds in our lives: Washington, D.C., U.S. Fish and Wildlife Service, p. 154–163.

Stewart, R.E., 1949, Ecology of a nesting red-shouldered 

hawk population: Wilson Bulletin, v. 61, no. 1, p. 26–35. 

Stewart, R.E., Cope, J.B., Robbins, C.S., and Brainerd, J.W., 

1952, Seasonal distribution of bird populations at the 

Patuxent Research Refuge: American Midland Naturalist, 

v. 47, no. 2, p. 257–363. [Also available at http://dx.doi.

org/10.2307/2422265.]

U.S. Geological Survey, 2011, History of Patuxent: Boston, 

MA, Northern Light Productions, U.S. Geological Survey 

video, 27 minutes, accessed February 28, 2016, at http://

www.pwrc.usgs.gov/history/history.cfm.
Other Programs at Patuxent

History of the Library at Patuxent Wildlife Research 

Center

By Lynda J. Garrett

Patuxent Wildlife Research Center (Patuxent) in Laurel, 

MD, celebrated its 75th anniversary in 2011. The Patuxent Research Refuge was established in 1936 and, in 1956, 

it was renamed the Patuxent Wildlife Research Center. The 

two names have been virtually synonymous throughout the 

decades since and although three agencies—U.S. Department of Agriculture (USDA), U.S. Fish and Wildlife Service 

(USFWS), and U.S. Geological Survey (USGS)—have managed the facility, the refuge and research staffs have acted 

essentially as one unit (Perry, 2004). The library has supported 

all the various management and research staffs located at 

Patuxent since its inception. This chapter recounts primarily the library’s history and staffing during the period I was 

employed there (1969–2013).

The library has been an important part of Patuxent since 

the establishment of the research facility. I worked in the 

Patuxent library for more than 43 years, but little information 

about its early days is available. The USDA library bookplates 

that can be found in many old volumes from the 1800s in the 

library hint at some sort of transfer or donation many years 

ago. Helen P. Alexander was Patuxent’s librarian for several 

years during the 1960s. She left Patuxent in the mid-1960s and 

later served at the brand-new National Agricultural Library in 

Beltsville, MD, which opened in 1969.

I applied for a position at Patuxent in February 1969. I 

was not interested in a career at that time because I expected 

my husband to be drafted soon. I was told I would need a 

Civil Service rating to be a candidate for a Federal job, even a 

clerk-typist position. I went to the Civil Service Commission 

(now Office of Personnel Management) in Washington, D.C., 

to take the test. Half of the test was multiple choice; the other 

half was typing! The only machines available were old manual 

typewriters. I had not touched one of those in years, so I did 

not pass the typing test. Thankfully, applicants could repeat 

that part of the test on another day, and were allowed to bring 

an electric typewriter. Therefore, I rented a portable electric 

machine and passed on my second try.

I arrived at my new Federal clerk-typist job in March 

1969, and operated the antiquated switchboard in the director’s office in the Gabrielson Laboratory building (Gabrielson), as a General Schedule- (GS) 3 employee, for 6 months. 

Gabrielson, which had just opened in December 1968, was 

named for Ira N. Gabrielson, the first director of the newly 

formed USFWS in 1940, who earlier had been influential in 

the creation of Patuxent Research Refuge in 1936. Evelyn 

Schoenborn was the director’s secretary, and my supervisor.

Ruth Nunnally was the GS-5 library technician, but no 

librarian position existed at that time. The director, Eugene 

Dustman, knew that Ruth planned to retire in the summer. 

He noted that I had listed previous library experience on 

my application and had me in mind to replace Ruth, which 

I did, in August 1969, as a GS-4. Ken Chiavetta became my 

new supervisor.

I had a break in service at Patuxent from July 1970 to 

November 1971, while my husband served his time in the U.S. 

Army in Kentucky. When we were ready to return to Maryland, I inquired about whether I might be able to have my 

old job back. However, Sue Samson was the library technician at that time, having recently arrived at Patuxent with her 

husband, Fred, who was a biologist. Therefore, I contacted 

my former supervisor, Ken Chiavetta, who arranged for me 

to have the job in the Pesticides Library located in the Merriam Laboratory (Merriam). The main duty there was mailing reprint requests on postcards for articles to be filed in the 

pesticides file cabinets—all 15 of them. That collection is still 

(2016) located in the basement of Gabrielson, room G10. Sue 

and Fred moved away in 1972 and, once again, I accepted the 

library technician position.

The library was on the second floor of Merriam. Initially, 

most of the library was in the large room that spanned the 

width of the building at the north end of the hall—room 212—

and was very crowded. Migratory bird biologists located in 

Merriam who were assigned to the newly formed Migratory Bird and Habitat Research Laboratory (MBHRL) were 

scheduled to move to Gabrielson. After the move, the library 

was assigned the vacated space and, consequently, was able 

to expand.

At that time in the 1970s, Patuxent housed two additional 

library collections. One was located in the Chemistry-Pathology building, later renamed the Stickel Laboratory. The other 

library collection, housed in Gabrielson, consisted of materials 

belonging to the Non-Game Bird Section. Chan Robbins, the 

section chief, and Ceil Nalley, a statistical assistant, looked 

after the collection. During the 1970s, those holdings served 

the newly created MBHRL, which disbanded in 1981 when 

migratory bird research returned to Patuxent.
236 The History of Patuxent: America’s Wildlife Research Story

The Merriam Library was supervised by Ken Chiavetta, 

the editor of “Wildlife Review.” Ferne Maines, a library aide, 

was also part of the library staff. “Wildlife Review” was a 

USFWS print quarterly index that was published in Chicago 

beginning in 1935. Following the retirement of Waldo McAtee, the editor since its inception, in 1948, “Wildlife Review” 

moved to Patuxent, where it was edited, in turn, by Neil 

Hotchkiss, Bill Stickel, and Ken Chiavetta. In conjunction 

with “Wildlife Review” activities, the Patuxent library developed extensive holdings in wildlife literature, and “Wildlife 

Review” became an invaluable reference for wildlife professionals (Humphrey, 1992). In 1975, both “Wildlife Review” 

and Ken were transferred to Fort Collins, CO. “Wildlife 

Review” continued as a print product until 1995, when the 

National Biological Service discontinued funding the publication because of budget reductions. The database continues 

today (2016) as a commercially available electronic title 

offered through subscription by EBSCO Publishing (Ipswich, 

MA) as “Wildlife and Ecology Studies Worldwide.”

In the spring of 1978, I took the Civil Service librarian 

equivalency exam. My passing score allowed me to move 

from a library technician position to a librarian position, GS-7. 

During 1975–83, the library was supervised first by Patuxent’s director, Lucille Stickel, and then by William Stickel, a 

renowned wildlife research biologist. The Stickels both retired 

in 1983.

In 1983, David Trauger became Patuxent’s director and 

established the Branch of Technical Services. The branch chief 

was biologist Nancy Coon. The Information Management Section was supervised by biologist Matt Perry, and included the 

library and manuscript tracking, which was handled by Nancy 

Bushby, a technical information specialist.

One of Dave Trauger’s early decisions was to consolidate all of the Patuxent library’s holdings into the Merriam 

location. He also authorized an extensive remodeling of the 

library. Work included painting the walls, painting all metal 

shelving and file cabinets, and installing carpeting and a 

drop ceiling. New shelving was added to rooms down the 

second-floor hallway to make room for titles relocated from 

the Chemistry-Pathology Laboratory and Gabrielson. The 

remodeling process required moving all library materials at 

least twice! Kinard Boone, a newly hired technician, did most 

of the moving each time.

In 1990, under Director Harold O’Connor, the Branch of 

Technical Services was abolished and its information-transfer 

functions were moved to the Office of Administrative Services 

under Joe Nagel. I was disappointed with this change because 

I believed that organizing the support services as a separate 

Branch of Technical Services underscored their importance 

and enhanced their visibility. In 1994, the library was moved 

again—this time to the second floor of Gabrielson. All of the 

stacks were in one room, but shelving space was reduced by 

about 10 percent. The pesticides and pollution collection was 

relocated to the Gabrielson basement, first to room G2 and, 

later, to room G10.

In the spring of 1996, just before Joe Nagel resigned, still 

another reorganization occurred; it placed the library under 

Information Resources Management (IRM), with Bob Munro 

supervising Wanda Manning, the library technician, and me. 

As a result of this reorganization, the library was again aligned 

with other technical support staff. In 2003, Bob retired and 

Rodney Payne was hired as the IRM coordinator. Rodney 

remained in this position until October 2008. Wanda Manning, 

who had worked at Patuxent since 1989, resigned in 2003. 

(Left to right) Dick Coon, Nancy Coon, Matt Perry, and Lynda J. Garrett in front of the current periodical display rack 

in the Patuxent Wildlife Research Center library, Laurel, MD, 2000. Photo by U.S. Geological Survey.
Other Programs at Patuxent

History of the Library at Patuxent Wildlife Research Center 237

Various part-time contractors and students followed until 

2009. Long-time library volunteer Betty Murphy left in 2010.

I was offered some generous travel opportunities during 

the years that the Federal Interagency Field Librarians Workshops were held. These workshops were held in Washington, 

D.C., in even years and in other cities (Denver, CO; Seattle, 

WA; and New Orleans, LA) in odd years. The training sessions provided during the workshops were valuable, but they 

were discontinued in 1986. In 1993, I traveled to Tucson, AZ, 

for museum property training because of a concern in USFWS 

headquarters that historical government property needed a different type of management.

The library at Patuxent supports research and the publishing of that research. The five functions discussed below—literature searching, interlibrary loan, journal subscriptions, 

cataloging, and the Patuxent bibliography—constitute the 

library’s support role.

Literature Searching

During most of my working years, computer literature 

searching was not available to the individual researcher. 

Librarians at the Department of the Interior Library completed requested literature searches until 1984, when Patuxent acquired an account with Dialog (now [2016] ProQuest 

DialogTM), which allowed our local Patuxent library personnel 

to complete precision searches. I ran these searches through 

the years along with IRM staff members Nancy Bushby and 

Nancy Hestbeck. By 2001, the Biological Resources Division 

(BRD) of the USGS began subscribing to “Cambridge Scientific Abstracts” (CSA), which later merged with ProQuest. In 

2005, BRD added the research tool Web of Knowledge (now 

[2016] Web of ScienceTM), which includes BIOSIS® and Zoological Record®. The Web of Knowledge/Web of ScienceTM 

research tools enabled all researchers to conduct independent 

searches. I completed several comprehensive searches to 

contribute to the preparation of books written by Patuxent 

staff members.

Interlibrary Loan 

Interlibrary loan (ILL) support has always been an important library function. Until 1980, ILL requests were typed on 

four-part forms and mailed to a library we hoped would own 

the book or journal. The ILL request process changed dramatically when Patuxent joined Online Computer Library Center, 

Inc. (OCLC), a worldwide library cooperative, in 1980. OCLC 

allows requests to be generated online to libraries that are 

listed as owners of the requested title; in addition, it allows the 

librarian to request an item from multiple potential lenders, 

sequentially, using the same request form.

Currently (2016), the Patuxent library staff fills almost 

twice as many ILL requests for other libraries as we originate 

ourselves, which reflects the breadth of our library holdings. Records indicate that in fiscal year 1991 (October 1990 

through September 1991), we requested 1,162 ILLs for our 

staff and filled 482 requests from other libraries. In fiscal year 

2011 (October 2010 through September 2011), we requested 

321 items and filled 488 requests. Filling article requests is 

faster and more efficient since the installation of a scanner in 

the photocopy machine. The ability to e-mail the portable document format (pdf) file has simplified the paperwork required 

and shortened the waiting time for the requesting scientist.

The major reason that we do not place or fill as many 

requests as we did in the past is the increase in the number of 

journal titles to which libraries have access online. The USGS 

Libraries Program subscribes to a comprehensive list of titles 

that are accessible to all USGS employees—an estimated several thousand unique journal titles in 2011. USGS-wide access 

to these materials maximizes the equitable availability of 

information to scientists and eliminates duplicate subscriptions 

among the various USGS library locations, thereby conserving 

financial resources.

Through the years, the use of ILLs has greatly contributed to the preparation of a number of books written by Patuxent authors. The successful completion of many of these large 

projects would have been difficult or perhaps even impossible 

without easy access to the great variety of literature that has 

been requested by the library. Patuxent library staff members, 

in turn, assist other researchers by lending books from the 

more than 6,000 Patuxent titles offered through the OCLC 

library utility.

Journal Subscriptions

It was easy to predict that Patuxent’s journal subscriptions would change as USGS-wide access to e-journals 

became more common, reducing the number of subscriptions 

the library purchases. Many researchers prefer the convenience of desktop access to publications. In 1995, we ordered 

about 160 print journal titles, whereas for 2011, we ordered 

just 26 print titles, and the price of some of those “core” titles 

included online access. Eventually, the list may be reduced 

to only those titles that do not offer online access. Another 

result of the availability of e-journals is that we no longer send 

journals to the bindery—in fact, the government contract binding company that Patuxent used for many years is no longer 

in operation.

Cataloging

Not long after my title was converted to librarian, I was 

offered the opportunity to attend a cataloging course in the 

Library Science program at the University of Maryland. By 

1980, when we prepared to join OCLC, Patuxent management decided to use Library of Congress cataloging for our 
238 The History of Patuxent: America’s Wildlife Research Story

collection and to discontinue the local scheme that was in use 

at the time. This decision modernized the library and greatly 

facilitated the day-to-day cataloging of our materials. By 

2002, we began offering our catalog online through Reference 

Manager Web Publisher software.

Patuxent Bibliography

During 1989–2010, the library was the fortunate recipient of the services of a devoted volunteer, Betty Murphy. Her 

project was to work in the Patuxent author archives, collecting 

copies of our past publications and placing them in the files in 

the Gabrielson basement. She also entered the citations into 

the ProCite (a proprietary commercial reference management 

software program) database that Nancy Bushby customized 

for the Patuxent bibliography in the mid-1980s, when Nancy 

was responsible for tracking manuscripts. This searchable 

database is currently (2016) available online and can be 

accessed from the Patuxent Web site (under “Our Products” 

[http://www.pwrc.usgs.gov/products/]), where many of the 

citations include the Universal Resource Locator (URL) link 

to the full text content.

Patuxent’s bibliography has been used to populate two 

other USGS databases. Our citations were uploaded to the 

USGS Publications Warehouse database in 2009 and, in 2010, 

I began using our bibliography to update our records in the 

USGS Information Product Data System (IPDS) report-tracking database. My involvement with the Patuxent bibliography 

has been one of the most satisfying projects of my career as 

a librarian.

The years I spent working at the Patuxent library have 

constituted a wonderful career—far more satisfying than 

teaching high school history, my first job upon graduating college. It was pure serendipity that caused my curiosity to lead 

me through the “wildlife” gate on Route 197 in Laurel, MD, 

in 1969.

References Cited

Perry, M.C., 2004, The evolution of Patuxent as a research 

refuge and a wildlife research center: Laurel, MD, U.S. 

Geological Survey, Patuxent Wildlife Research Center, 

20 p., accessed November 3, 2011, at http://www.pwrc.usgs.

gov/history/cronhist/patuxenthistory_perry.pdf.

Humphrey, J.A., 1992, The history and uses of Wildlife 

Review and Fisheries Review: Galveston, TX, International 

Association of Aquatic and Marine Science Libraries and 

Information Centers, Conference Proceedings, p. 207–213, 

accessed November 3, 2011, at http://hdl.handle.

net/1912/1670. 

Dr. Lucille Stickel, U.S. Fish and Wildlife Service, 

a major supporter of Patuxent Wildlife Research 

Center library holdings and functions in the 1960s 

and 1970s. Photo by U.S. Fish and Wildlife Service.
Other Programs at Patuxent

Patuxent’s Research Program in an Era of Transitions

James A. Kushlan

Introduction

It was a telephone call to me, not totally unlike that 

received 9 months earlier by Ron Pulliam (Director of the 

National Biological Survey [NBS]) from Bruce Babbitt 

(Secretary of the Interior), which has since entered the lore of 

United States wildlife conservation history (Pulliam, 1998). 

The call, in the summer of 1994, bore an offer I never would 

have imagined being given to me, nor being accepted by me. 

It differed from Pulliam’s job offer experience in that I had 

indeed applied for the position, albeit solely at the behest of 

long-time colleagues at the Patuxent Wildlife Research Center 

(Patuxent) in Laurel, MD. They had been promised an open 

search for a new director of Patuxent. I had applied to test 

whether the promise was true.

The NBS director requested on my behalf, and I 

received, an unprecedented 3-year leave of absence from the 

University of Mississippi, where I was then chairman of the 

biology department. Previous appointees to Federal agency 

positions had received only their allocated 2 years. I was 

honored to have the offer to lead what in my early professional career was viewed by all as the most important research 

facility in all of wildlife biology. I wanted to help scientists 

publish science that was, in fact and in appearance, credible 

and nonadvocative. This concept had gained traction in recent 

years (National Academy of Sciences, 1992), and helping to 

see it through was appealing to me.

I did revel in the possibilities of facilitating expansion 

of the biological knowledge base available to the Department of Interior (DOI) land-management agencies, especially 

for migratory birds and even more especially for waterbirds. 

Therefore, I agreed to undertake what was to be a 3-year 

tour of duty helping Patuxent during its transition and assisting my colleagues in the process. To be sure, I knew at the 

time that it would be a difficult, although fascinating, task, 

and I could proceed boldly dealing with management of a 

research facility.

Of course, grand plans rarely work out as anticipated. It 

turned out that the Patuxent at which I arrived in the fall of 

1995 had been shorn of its field stations and renamed Patuxent Environmental Science Center (Perry, 2004). Its budget 

was to be cut $1.5 million and, to accommodate this reduction 

in funding, one option was to reduce the staff by about two 

dozen people and eliminate functionality. In October 1996, 

Patuxent’s remaining functions were transferred to the U.S. 

Geological Survey (USGS). This chapter describes the story of 

that transitional period at Patuxent: transitions in form, function, structure, aspirations; transitions in the trajectory of many 

professional careers; and transitions in agencies, including the 

U.S. Fish and Wildlife Service (USFWS), NBS, National Biological Service, and USGS, and their differing perspectives. 

It also is the beginning of the story of the future of biological 

science in the DOI, a tale that as of this writing more than two 

decades later (2016) has yet to completely unfold.

A History of Agency Roulette

It is generally acknowledged that wildlife studies came 

into the Federal government in 1885 with the establishment 

of a Section of Economic Ornithology within the Division 

of Entomology at the Department of Agriculture (USDA) 

(Allen, 1954). Its early focus, as that organizational hierarchy 

indicates, was on the negative and positive relations between 

birds and agriculture. What birds were there, where, when, and 

what did they eat? In 1896, the group became the Biological 

Survey and, under President Theodore Roosevelt’s patronage, 

the Bureau of Biological Survey (Bureau) in 1905. President 

Roosevelt was one of the great naturalists of his era, an observant amateur ornithologist, and a widely accepted scientific 

mammalogist (Kushlan, 2011). Roosevelt admired the USGS 

and he wanted a biological equivalent. Under Roosevelt’s 

direct influence, the Bureau added mammals to its emphasis, 

along with the new natural history museums and zoos (Matthiessen, 1959). The Bureau also delved into bird and mammal taxonomy and distribution, and their status and trends. 

The enforcement of the 1900 Lacey Act, which prohibited the 

interstate transfer of birds killed in violation of State laws, also 

became their responsibility. The identity, name, and function of the Bureau had lasted a long time—35 years—when 

a merger with the Bureau of Fisheries of the Department 

of Commerce produced the USFWS, all in the DOI. It was 

during this period, in part to address the habitat destruction 

that characterized the Dustbowl Era, that scientific wildlife 

management began in earnest, focusing first on waterfowl and 

fishery stocks (Matthiessen, 1959).

The wildlife research function known as Patuxent took 

life on December 16, 1936, when President Franklin D. 
240 The History of Patuxent: America’s Wildlife Research Story

Roosevelt signed Executive Order 7514, transferring land 

along the Patuxent River in Maryland to the USDA and authorizing it to be used as a research refuge, essentially a wildlife experiment station equivalent to the nearby agricultural 

experiment station, in support of the Migratory Bird and Conservation Act (Perry, 2016). The Patuxent Research Refuge 

was officially dedicated on June 3, 1939, and moved from the 

USDA to DOI with the USFWS. As habitat was the principal 

research question of the time, much of the work over the next 

decades centered on the land base of the experiment station, 

including its fields, woodlots, and constructed wetlands. From 

the time the first director, Arnold Nelson, was appointed, the 

research and the land were under common management.

With the reorganization of the USFWS in 1956, the 

Patuxent Research Refuge was administratively renamed the 

Patuxent Wildlife Research Center. Over the decades, Federal 

wildlife research needs broadened gradually from habitat to 

such issues as harvest management, and then further to population dynamics, pesticides, endangered and declining species, 

and nongame birds. With this expansion of need, Patuxent 

grew in mission, staffing, physical plant, and geographic 

reach, becoming the largest and arguably the most famous 

wildlife research laboratory in the world (Perry, 2016).

By the early 1980s, an increasingly complex array of 

research activities derived from multiple sources was administratively reorganized into disciplines within a centralized 

structure made to conform to modern management principles. 

In the late 1980s and early 1990s, Patuxent management 

explicitly chose to add roles of public use and outreach to 

its science core (Ballard, 1989) as the Laurel (MD) campus 

was expanded by incremental increases of land from adjacent 

Federal agencies and by the building of the National Wildlife 

Visitor Center, which was funded to highlight the USFWS 

research history. These role expansions and facility transactions altered both the function and the funding of Patuxent in 

fundamental ways. Patuxent had always been run on funds 

appropriated to the USFWS for the research region (Region 8 

in Washington, D.C.), and had always been managed solely as 

a research facility (Perry, 2004).

With increased public use and new facilities and lands 

to manage, these core funds by necessity were increasingly 

used to pay for nonresearch matters. Finally, in 1992, additional funds were appropriated to the USFWS Northeast 

regional office for Patuxent, a refuge manager was appointed 

to serve under the director, and plans were underway to divide 

responsibilities between the refuge managers of the region 

and Patuxent, with Patuxent retaining management control 

of the historical core of the land and the refuge system taking 

over the rest (Perry, 2004). This plan did not materialize. At 

its peak, Patuxent was an institutional juggernaut. It comprised more than 200, mostly scientific staff members; 11 field 

stations; a $20 million budget; and 12,800 acres of land and 

facilities (Perry, 2004).

On Earth Day, April, 21, 1993, President Clinton 

announced his intention to undertake a biological survey of the 

Nation. This announcement, a single sentence in his speech 

(http://www.presidency.ucsb.edu/ws/?pid=46460, accessed 

July 30, 2015), articulated the vision of his Secretary of the 

Interior, Bruce Babbitt, who, like Roosevelt, was an admirer of 

the USGS in his youth, wanted a biological equivalent of the 

USGS, wanted an agency where science was independent of 

the land-management bureaus, and wanted enhanced capacity 

to provide the inventories and scientific studies the agencies 

needed. His rationale was to get ahead of oncoming environmental crises (Stone, 1993).

The new bureau was to be formed by extracting the 

research functions and staff from the other DOI agencies. 

It was organized within the 1994 budget process accompanied by the passage of authorizing legislation in the House 

of Representatives, but not in the Senate, leaving the agency 

as administratively and budgetarily authorized, but not 

organically established. But, carrying the vision on, Secretary 

Babbitt signed an order (Secretarial Order 3165) on May 17, 

1993, announcing his intention to create the new bureau and 

setting that process in motion. On August 20, 1993, letters 

were mailed transferring personnel with their functions as of 

passage and signing of the fiscal year (FY) 1994 budget beginning October 1993.

Among other science functions transferred to the NBS 

were other DOI research centers (some historically spawned 

by Patuxent), Cooperative Research units at land-grant universities, and research scientists from the National Park Service 

(NPS) and other bureaus. Also among functions and personnel 

transferred to the NBS were several from the USFWS Migratory Bird Management Office such as the Bird Banding Laboratory, Breeding Bird Survey, and other inventory activities; 

the NPS’s Center for Urban Ecology; the USFWS Biological 

Survey Group housed at the National Museum of Natural History; NPS Cooperative Parks Studies Units at universities; and 

park-based research scientists.

In June 1994, University of Georgia professor Ronald 

Pulliam became director of the NBS and took over forming 

his agency. It was to be academic, scientific, independent, 

unbiased, peer reviewed, and agency responsive, and to 

address more than wildlife. It would additionally be about 

ecosystems and technology and tend to big questions of ecology and resource management (Stone, 1993). On January 5, 

1995, Secretary Babbitt (Secretarial Order 3185) changed the 

agency’s name to National Biological Service and clarified 

that its primary role was to meet the biological research needs 

of the DOI. The agency was short-lived.

A new Congress elected under House of Representatives 

Speaker Newt Gingrich’s leadership took office in January 

1995. His “Contract with America” had formally promised 

to abolish the NBS (Pulliam, 1998a). In 1996, the functions 

and employees of the NBS became part of the Biological 

Resources Division of the USGS (Pulliam, 1998b). Additional 

transitions were in store for everyone. Patuxent’s identity, 

form, and functions underwent substantial changes during this 

period (Perry, 2004).
Other Programs at Patuxent

Patuxent’s Research Program in an Era of Transitions 241

Identity

Name changes quickly became an issue. What had been 

for decades Patuxent Wildlife Research Center was renamed, 

as of May 10, 1994, Patuxent Environmental Science Center. 

By the time of my arrival in 1995, the decision had long since 

been made to change Patuxent’s name (Perry, 2004). Among 

my first assignments was to call on Maryland Senator Paul 

Sarbanes, who wanted Patuxent’s original name reinstated 

(Perry, 2004). The order came out a few days later, and at 

Patuxent we had a celebration to enjoy our name restitution. A 

name change did not change anything fundamentally, but was 

psychologically uplifting. 

With a new logo featuring the bald eagle (Haliaeetus leucocephalus), the identity of Patuxent had returned to its roots. 

When moved to the USGS, it officially became “USGS Patuxent Wildlife Research Center,” but it always remained for most 

just “Patuxent.” Of course, outside the wildlife community, 

“Patuxent” is a Naval air station, a prison, or a Maryland river. 

Within the wildlife community, it remained one of the centers 

of its science.

Form

The form I found at Patuxent in 1995 was in my view 

entirely logical in that its three main disciplinary functions, 

each with its independent history, were divided among three 

branches for migratory birds, contaminants, and endangered 

species. Each had a mid-level manager, who controlled the 

branch budget and supervision, and each had an administrative staff. Scientists were further divided into groups, 

each with a supervisor. The form of Patuxent consisted of a 

centralized command structure, based on the concept of Total 

Quality Management (TQM) (https://en.wikipedia.org/wiki/

Total_quality_management, accessed July 30, 2015) enacted 

by a Quality Council that met long and regularly. When I first 

entered Patuxent’s conference room, on the wall was a sign 

assuring the staff that TQM meant that whatever was said in 

this room by the Quality Team members of TQM stayed in this 

room and that employees could express their opinions without 

fear of retribution. 

The potential imposition on creativity of TQM in a 

research environment worried me, and after a couple of 

months of consideration, I terminated TQM and the threebranch structure. Instead, all the research scientists were to 

report to one chief scientist and were encouraged to selforganize into recognized, but nonsupervisory, teams around 

projects, themes, or fields of work as they chose. This was an 

academic department model. It also eliminated the overhead 

costs of two layers of management. Finally, the concept of 

base funding branches was ended in favor of funding on a 

project basis supported by peer-reviewed proposals that competed for available base funds.

Scientists found freedom to do the work they chose, 

staying within the overall mission of servicing DOI, so long 

as they could competitively or by partnership acquire funds 

for their work and publish it in peer-reviewed journals. USGS 

headquarters was behaving somewhat similarly, offering funds 

derived from proposal-driven competition within the agency, 

and Patuxent scientists did well in this competition. Therefore, 

all Patuxent research became derived from internal or external 

peer-reviewed proposals.

Function

The NBS on its creation immediately became regionalized, with Patuxent reporting not to DOI headquarters in 

Washington, D.C., as it had for 60 years, but to a regional 

office in West Virginia. Implicit in this regionalization was 

that Patuxent was no longer to be a national laboratory, but a 

regional one. Patuxent was stripped of its far-flung field stations, and now consisted of the Laurel campus, including the 

National Wildlife Visitor Center; staff in Maine; the research 

and curatorial staff assigned to the U.S. National Museum 

(taken from the Denver Research Center); and the Center for 

Urban Ecology (taken from the NPS). The Smithsonian-based 

scientists were the taxonomic, curatorial, and distributional 

experts from the USFWS. These acquisitions brought taxonomists, mammalogists, herpetologists, botanists, urban ecologists, and wetland scientists to Patuxent.

The new agency’s initial functional areas and budget 

categories were to be species biology, population dynamics, 

ecosystems, inventory and monitoring, and technology development and transfer (Stone, 1993). Species biology, population dynamics, and monitoring were within Patuxent’s capabilities; ecosystems were not, even though this was clearly to 

be a principal focus for the new agency. Clearly in the new 

agency’s organization, the initial intention was for Patuxent 

to have an eastern focus (Perry, 2004). Patuxent did wildlife 

research on a national, and sometimes international, scope for 

the entirety of the USFWS. Hal O’Connor and Dave Trauger 

(respectively, Director and Deputy Director of Patuxent) had 

gone through a strategic planning process, finished in October 1993, to attempt to align Patuxent more closely with the 

mandates of its new bureau and to face up to its new realities 

(Patuxent Wildlife Research Center Quality Council, 1993).

Within the NBS mission elements of species and population dynamics research, Patuxent was able to see the disciplines that had made it famous. National programs continued 

with contaminants and endangered species. Migratory birds 

research was clearly to be as much in the future of Patuxent as 

it was in the past. In the transition, the NBS failed to accumulate all of the USFWS migratory bird science capability, and 

Patuxent had received no new migratory bird personnel and 

even lost some from its former field stations to other regions; 

still, this was Patuxent’s strength and a logical growth area. 
242 The History of Patuxent: America’s Wildlife Research Story

Given that developing geographic information system capabilities and ecosystem- and landscape-scale biological conservation was a fast-moving field for wildlife research, thinness of 

staff was indeed worrisome. Something needed to be done 

there. It is worthwhile, therefore, to examine Patuxent’s science capabilities at the beginning of NBS.

Endangered Species

Patuxent was long the national leader in terrestrial 

vertebrate endangered species research, starting in 1965. It 

was a leader after the passage of the first Endangered Species Act, ready to support the new Federal role in biodiversity 

conservation, under the leadership of Dr. Ray Erickson (see 

the “Endangered Species” section of this report). It did the 

seminal species, reintroduction, and contaminant research on 

the bald eagle (Haliaeetus leucocephalus), osprey (Pandion 

haliaetus), brown pelican (Pelecanus occidentalis), California 

condor (Gymnogyps californianus), masked bobwhite (Colinus 

virginianus ridgwayi), Puerto Rican parrot (Amazona vittata), 

whooping crane (Grus americana), Mississippi sandhill crane 

(Grus canadensis), gray wolf (Canis lupus), and black-footed 

ferret (Mustela nigripes). By 1995, much of this reintroduction work had passed operationally to management agencies. 

Patuxent’s one remaining program in the endangered species 

branch was on cranes.

The crane program had persisted, and the issue of cranes 

was front and center in the National Biological Service continuing in the Biological Resources Division of the USGS. I 

impaneled a peer-review team (Scott and Sparrowe, 1999), 

which agreed that the program should be confined to research; 

defined the research needed as being studies on reintroduction, not husbandry; and called for maintaining the captive 

stock needed for this research. An implementation plan for a 

reintroduction program was developed on the basis of peerreviewed proposals and, to support this work, no birds were 

moved. Thus, the whooping crane propagation at Patuxent 

survived unabated. Patuxent itself had neither the money nor 

the mandate to lead the reintroduction program, but encouraged partners to do so. In addition to the crane program, Dave 

Mech’s long-term wolf study for a time was returned to Patuxent, and Jeff Spendelow in the migratory bird program studied 

roseate terns (Sterna dougallii). 

CANUS (for Canada and the United States), the first whooping crane of many 

in the captive colony at the Patuxent Wildlife Research Center, Laurel, MD, 

1991. Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.

Captive bald eagle at Patuxent Wildlife Research Center, Laurel, MD, 1979. 

Photo by Matthew C. Perry, U.S. Fish and Wildlife Service.
Other Programs at Patuxent

Patuxent’s Research Program in an Era of Transitions 243

Immature roseate tern (Sterna dougallii) color banded for monitoring, 

Chatham, MA, 2011. Photo by David Monticelli, Marine and Evironmental 

Sciences Centre, Universidade de Coimbra, Portugal.

Contaminants

Patuxent was once the national leader in wildlife contaminant research, which had started in the mid-1940s. Under 

Director Lucille Stickel’s leadership, Patuxent was able 

to benefit from attention to pesticides after Rachel Carson 

published “Silent Spring” in 1962 (Carson, 1962) to build a 

program that soon had continent-wide implications. By 1995, 

the program was still producing a substantial number of publications on contaminant effects on wildlife. Much of this work 

dealt with detailing the questions; summarizing and synthesizing the data; and attempting to address the then-current, 

but technically difficult, issue of secondary and generational 

effects by using Patuxent’s remaining captive colonies of 

American kestrels (Falco sparverius) and Eastern screech 

owls (Megascops asio).

In the transition to the NBS, the Analytical Control Facility established in 1985 and housed at Patuxent (Perry, 2004) 

remained with the USFWS, with the rationale that this facility 

was a scientific service, not research. One functional result 

was that Patuxent lost its research chemists. Nonetheless, in 

1995 Patuxent housed a cadre of contaminant biologists. As 

demand for their expertise decreased, they documented the 

continuing progress of environmental regulation. This work 

continued in the 1990s and thereafter, with special attention to 

Chesapeake Bay.

Migratory Birds

Patuxent in its largest sense (that is, including entities at 

the Laurel site not necessarily administered by Patuxent) in 

1995 was still one of the world leaders in migratory bird studies. The bureaucratic history is convoluted, as several Federal 

migratory bird science entities over the previous decades had 

been established, merged, disestablished, or remerged (Erwin 

and Blohm, 2016). But over the years prior to the agency transition, migratory bird functions had been rearranged a couple 

of times, with some eventually becoming part of Patuxent 

and some remaining in the offices dealing with migratory bird 

management and habitat. Upon the emergence of the NBS, 

some of these functions, including the Bird Banding Laboratory (BBL), Breeding Bird Survey (BBS), and similar functions, were transferred, but were managed by headquarters, 

leaving part of the migratory bird capabilities in the USFWS, 

part in Patuxent, and part reporting to NBS headquarters, 

but nearly all colocated at the Laurel site. Thus, the core of 

the former and present USFWS migratory bird research and 

migratory bird management functions still resided physically 

at Laurel by 1995.

After the transition, it became clear to me that Patuxent could seek out this role to amalgamate all the former 

USFWS migratory bird science functions within the NBS. So 

a campaign was launched by others and me to secure transfer 

of at least the BBL and BBS from headquarters to Patuxent. 

I believed it to be a scientifically and logistically feasible 

proposition. This proposal was agreed to, with much credit 

going to USGS Chief Biologist Sue Haseltine, and these 

programs, along with personnel from the Office of Inventory 

and Monitoring, were transferred to Patuxent management. 

Patuxent then sheltered the most important of DOI’s long-term 

bird monitoring programs, which were always considered to 

have been part of Patuxent in any case (Robbins, 2016; Tautin, 

2016). The BBS, started by Chandler Robbins, had always 

physically resided at Patuxent. The BBL and the Electronic 

Data Processing center had resided at the Laurel site since 

1942. These national responsibilities for bird monitoring were 

accommodated at Patuxent by erecting for the Monitoring 

Program a second supervisory section coequal with Research.

It was apparent to nearly all that the functionalities of the 

BBL were seriously out of date, relying on paper data forms; 

proprietary and idiosyncratic computer programs; severe and 

sometimes unfathomable restrictions on awarding banding 

permits; tight, centralized, person-mediated quality control of 

data input; and limited and highly controlled data availability. 

The BBL had long focused on waterfowl harvest, but, clearly, 

the BBL was a critical adjunct to ornithological research and 

many levels of resource management. Innovative programs 

for monitoring bird demography, color banding, and satellite 

telemetry were being initiated. To address these changes in the 

scientific community and to settle the BBL in its new bureaucratic home, a peer-review panel was commissioned prior to 

my arrival, although its report was not published until 1998 

(Buckley and others, 1998). Upon its completion, I impaneled an implementation committee that included personnel 

from the USFWS, conservation organizations, and academia. 

Under the leadership of John Tautin, slowly but surely, the 

BBL was “reengineered” and brought into the electronic and 

communication age (Tautin, 2008, 2016). The process led to 

developments such as having Federal prisoners make bands, 
244 The History of Patuxent: America’s Wildlife Research Story

encouraging recoveries by telephone, and attempting to make 

programs more user friendly. Eventually, the data-processing 

unit was, for efficiency, merged with Patuxent’s other information functions and the BBL became essentially all electronic, 

relying on the World Wide Web for its functionality.

Similarly, I impaneled a review team led by Raymond 

O’Connor (University of Maine, Orono) to review the operation of the BBS (O’Connor and others, 2000). Its conclusions 

were the well-accepted consensus opinions about what might 

be done better. The BBS was designed in the days of paper 

field notebooks, and wildlife biologist Bruce Peterjohn had 

already led it into the electronic era, long before the BBL was 

able to do so. An implementation plan that followed up on the 

recommendations was put into action as funding allowed.

Monitoring

Given my emphasis on research independence and 

eliminating middle management, the observant reader might 

ask why there was a Monitoring Division separate from the 

Research Division. The reason for the internal organization 

within Patuxent was twofold. The activities of the Monitoring 

Division, although scientific, were not necessarily research 

functions, and the biologists were not research scientists, but 

focused on customer service. The new Monitoring Division 

arrangement soon expanded to encompass colonial waterbird, 

amphibians, and pollinator monitoring programs, with Patuxent serving as the operational and data hub.

A “downside” of the separation of function was that 

a recognizable research/nonresearch divide came to exist 

within the science of Patuxent between publishing research 

scientists and database-managing scientists. The migratory 

bird data-managing scientists became increasingly separated, 

Patuxent Wildlife Research Center biologist Sam Droege monitoring bees with 

a sampling net, 2005. Photo by U.S. Geological Survey.

organizationally and intellectually, from the migratory bird 

research scientists. The migratory bird programs were eventually successfully coalesced by my successor, Dr. Judd A. Howell, under a single supervisory unit. After many years, Federal 

migratory bird science had achieved a unified home.

Reexpansion

With the loss of its distant field stations, scientific personnel, and geographic scope in the mid-1990s, Patuxent had 

contracted in multiple ways. Accumulation of monitoring 

programs increased personnel, expanded the program, and 

reestablished a national scope of work. But Patuxent could 

have benefited from employing additional scientists, especially 

because it initially lacked expertise in subject areas important 

to the National Biological Service, and later to the USGS—

especially ecosystems; landscape ecology; climate change; and 

similar big-question, nonbird issues. Some of this expertise 

could be gathered as positions became available, and a plan to 

guide future disciplinary hires was created.

A campaign was launched by Patuxent management staff 

to recruit these scientists to Patuxent, whose history, administrative expertise, and prestige were positive arguments. In 

the end, Patuxent accumulated, in addition to the National 

Museum scientists and its Maine bird-focused field station, 

the NPS research units at the Universities of Rhode Island, 

Boston, and Syracuse, incorporating a wide range of park 

science positions including coastal geology and entomology; 

the NPS-derived visitor impact research program at Virginia 

Polytechnic Institute and State University; the world-famous 

wolf research program located in Minnesota; the contaminant 

and bird, and, later, freshwater researchers at the University 

of Georgia (Director Pulliam’s home institution); and the bird 

research station with the multiagency partnership of the Lower 

Mississippi Joint Venture in Mississippi. As job openings 

and opportunities became available, positions were filled in 

the areas of migratory birds, monitoring, bird conservation 

planning, urban ecology, landscape ecology, and population 

dynamics, and in the reamalgamation of a wetland ecology/

landscape/climate-change group that originally had coalesced 

at the wetlands center in Lafayette, LA, under the leadership 

of Dr. Robert Stewart.

In tight economic times, the perceived need and willingness for partnerships can increase. Patuxent had retained 

its solid relations with national wildlife refuges in the midAtlantic and Northeast and, owing to the addition of the Rhode 

Island unit, gained new connections with national parks in 

the Northeast. Buoyed by the long-term cooperation among 

refuges and parks, studies continued in these areas. Patuxent 

had multifaceted and positive relations with the migratory bird 

leadership and scientists in the USFWS, especially under the 

leadership of Paul Schmidt, Dave Smith, and Jon Anderson 

in Washington, D.C. Combined programs, joint committees, the North American Waterbird Conservation Initiative, 
Other Programs at Patuxent

Patuxent’s Research Program in an Era of Transitions 245

cooperative policy setting for the BBL and BBS, parallel 

migratory bird science directions, and administrative issues 

were all collectively managed.

Patuxent continued and expanded its involvement with 

Chesapeake Bay by establishing relations with the leadership 

of the U.S. Environmental Protection Agency-managed Chesapeake Bay Program, the USFWS Chesapeake field office, the 

University of Maryland research campuses on the Eastern 

Shore and Solomon Island, the Smithsonian Environmental 

Research Center, and the Eastern Shore wildlife refuges. 

Scientists were engaged in species, restoration, wetland, and 

contaminant research over much of Chesapeake Bay and its 

watershed. Patuxent had acquired the science component of 

the Lower Mississippi Joint Venture, which was then under the 

leadership of Charles Baxter. It also engaged with the Atlantic 

Joint Venture, offering space for its science staff. It brought 

to Patuxent science staff of the USDA Natural Resources 

Conservation Service, with which I had worked in Mississippi. Patuxent had alumni in Cooperative Research Units at 

several universities, so these collaborations continued. The 

USGS State Water Science Centers were seen as potential collaborators, and several staff colocations occurred. Following 

the NPS example, Patuxent began to establish its scientists at 

various research universities, as it was clear that Patuxent-university partnerships were to be extremely valuable by increasing productivity.

Partnerships overall were generally beneficial, as they 

multiplied resources and encouraged scientific interchange. 

Partnerships can be difficult in practice, however, as institutions are sometimes in competition. In my opinion, partnerships worked best when they were forged by the scientists 

themselves; however, the partnership effort at the leadership level proved useful during the early period of reintroduction and trust building among entities, as it appeared 

to reduce impediments for scientists when they chose 

their collaborations.

Staff and functional acquisitions, targeted hiring, outplacements, and partnerships allowed Patuxent to reexpand. 

Eventually, staff was located at the Smithsonian Institution and 

seven universities as well as water-resource and environmental service offices in addition to the Laurel facility. By 2001, 

Patuxent encompassed 150 positions at 13 locations from 

Maine to Georgia, with a substantially broadened disciplinary scope. Patuxent’s science purview had been reestablished, 

with both regional strengths and national programs.

Bird Conservation

Given its history, prior reputation, staff expertise, accumulation of well-respected bird biologists throughout the 

East, and responsibility for national bird databases, Patuxent 

was in a position to participate in and affect the bird conservation movement, and participated in conservation planning 

and other wildlife organizational structures with all of these 

nongovernmental organizations. Patuxent had for decades 

been an active participant in the Black Duck Joint Venture. 

It sponsored the organizational meeting for a Sea Duck Joint 

Venture. It had a field station in the “hot spot” of migratory 

bird land management thought and practice in Mississippi. 

After the alternatives had been analyzed, the BBS, established 

by Chan Robbins, turned out in my opinion to be the best way 

of estimating status and trends of North American migrant 

birds. The BBS bird point-count data have been digitized and 

archived (Robbins, 2016); Chan also undertook to digitize the 

Audubon Breeding Bird Censuses (Robbins, 1977). Patuxent 

recreated the colonial waterbird colony database (Erwin and 

Blohm, 2016), which it had first set in motion in the 1970s. 

Complementing and working with Partners in Flight and the 

U.S. Shorebird Plan, Patuxent took the lead in developing 

the North American Waterbird Conservation Plan (Kushlan 

and others, 2002). As these planning efforts came to fruition, 

Patuxent found itself a key player in the development of a 

continent-wide approach to bird conservation, crystallized 

in the public-private partnership of the North American Bird 

Conservation Alliance (Yaich and others, 2000). Patuxent 

scientists were active participants in the important scientific 

discussions about the North American Bird Conservation Initiative (NABCI), especially population status and trends and 

monitoring, and eventually in the state of the bird reports.

Funding

The story of any Federal entity is tied to the story of its 

funding. Patuxent’s funding during the period discussed in this 

chapter is shown in figure 1. 

The reduction in funding from FY 1995 to FY 1996 

included the loss of more than half of Patuxent’s base funding. 

Instructions for dealing with this reduction were threefold: 

The Center for Urban Ecology was to be closed, half of the 

facilities funding was withdrawn, and employees needed to be 

terminated (which was called a reduction in force). With this 

decision, much of the urban planning and park science capabilities used by the NPS that had recently accrued to Patuxent 

was lost.

The loss of facilities support can be understood from 

the immediate prior history of Patuxent, when its management emphasis had shifted from pure research to, in addition, 

accumulating lands, building a Visitor Center, public use, and 

outreach. Apart from directed appropriations for construction, 

which indeed covered most of the costs, funding for management of the Visitor Center and of the lands of Patuxent came 

from the USFWS research budget, which was arguably viewed 

by some as decreasing the money available for research.

The rest of the decision making was left to Patuxent. 

Because the funds available for salary were insufficient to 

support the existing staff, I had to let some employees go. I 

made the decision to protect the research at all costs; therefore, 

no cuts and no reduction in force occurred for research and 
246 The History of Patuxent: America’s Wildlife Research Story

immediate research support positions (other than the Center 

for Urban Ecology). The rest of Patuxent took a substantial 

functional blow as facility, administrative, and other support 

staff positions were eliminated. Managing the force reduction 

required all of my available personal and professional skills. 

The result was that 26 people were fired, and, overall, 35 positions were vacated. These actions inevitably had adverse 

consequences for both morale and functionality at Patuxent. In 

any organization, recovery from such a mass firing can require 

a professional generation. The reduction in force was perhaps 

especially devastating for a Federal workforce for whom job 

loss was not in their history. 

The FY 1996 and 1997 budgets reflect the Visitor 

Center’s move to the USFWS (see the disappearance of the 

yellow part of the bar in figure 1). Although it initially came 

to the NBS, it was transferred back because it did not have a 

science function. This facility was funded to highlight the history of USFWS science throughout the United States, including Patuxent. Instead it became a highlight of the Patuxent 

Research Refuge. The FY 1997 budget shows the accretion 

of funds to support the monitoring program (shown in red in 

figure 1), including the BBL, the BBS, and other monitoring 

functions transferred to Patuxent. There was a steady increase 

in funding available for research beginning in FY 1998, 

peaking at more than $9 million in FY 2001 (shown in white 

in figure 1). Monitoring funds also increased, to a little less 

than $3 million in FY 2001. By FY 2001, research funding 

at Patuxent had returned to the level seen in FY 1993, before 

implementation of the NBS, which was able to support its 

return to national and international engagement.

Facilities and the Land

Unexpectedly, facilities issues as well as science drove 

much of the transition at Patuxent’s Laurel, MD, campus. 

Historically, as noted above, Patuxent and the land on which 

it stood were indistinguishable. The director of Patuxent was 

responsible for the research and for the land, which was used 

entirely for research, and facilities were built and converted to 

support it. From this trust of land and facilities came many of 

the internationally known fundamental management protocols 

for wetlands, refuge impoundments, game-bird enhancement, 

endangered species conservation propagation, bird banding, 

migratory bird conservation, contaminant studies, and the long 

list of other wildlife management advances. Patuxent and the 

lands were one. This relation became more complicated when 

additional lands, to be known as the South Tract and the North 

Tract, were accreted to the historic Central Tract from other 

Federal entities in the early 1990s. These lands were not intrinsically useful for research, but did add public use and even 

consumptive uses to the mix of management needs. Research 

and public use are generally not really compatible activities. 

Facilities money in support of research at Patuxent 

disappeared in four steps. Many of the research facilities and 

Funding, in millons of dollars

20

15

10

5

0

1993 1994 1995 1996 1997 1998 1999 2000 2001

EXPLANATION

Visitor Center

Monitoring program

Research program

Facilities (without major maintenance)

Administration and Director’s Office

Allocation

Figure 1. History of Patuxent Wildlife Research Center funding 

allocations, 1993–2001. (Graph modified from an unpublished 

presentation made by J.A. Kushlan at a meeting of Patuxent 

Wildlife Research Center staff, Laurel, MD, January 23, 2001.)

buildings at Patuxent were old, some historically so. It was 

certainly the case that in adding lands and the Visitor Center, funds that used to support these research facilities on the 

Central Tract were now used for broader purposes, resulting in 

an acceleration of degradation of the research facilities. Second, when deep budget cuts hit the NBS in FY 1994–95 and, 

because of the past history of Patuxent management accreting 

nonresearch responsibilities, Patuxent lost half of its facilities 

funds (see above). I recall well making a speech to the staff to 

urge them to think of Patuxent as consisting of people, not land 

and buildings—good for morale, but the land and the historic 

buildings were in Patuxent’s “blood.” 

The Future

This story as of this writing (2016) ended two decades 

ago; so much of what was then “future” has already passed. 

There have been three subsequent Patuxent directors and a 

USFWS refuge manager. Patuxent moved much of its staff to 

the USDA Beltsville Research Station and collapsed its office 

presence to one building. The biology discipline is no longer 
Other Programs at Patuxent

Patuxent’s Research Program in an Era of Transitions 247

an organizational unit of USGS. Since 2002, the USGS has 

divided its science programs and funding streams into the 

“mission areas” of climate and land-use change, core science 

systems, ecosystems, energy and minerals, environmental 

health, natural hazards, and water. 

The USFWS and the USGS appeared to have engaged 

constructively to optimize existing science capabilities (Cohn, 

2005). The next generation of managers and scientists will 

decide how the story of DOI biological science that began 

in the era of transition will proceed into the middle of the 

21st century.

Acknowledgments

I acknowledge with friendship and gratitude the people 

of the U.S. Geological Survey (USGS) Patuxent Wildlife 

Research Center (Patuxent), who are and always were exceptional people in many ways, and those who served as leaders 

and partners through the years of this story. Although I cannot 

name all of the hundreds of people who were in this mix, I 

would like to express my gratitude to some by name. First, 

thanks to Ron Pulliam and Sue Haseltine, and Dennis Fenn 

(USGS), who provided input to my historic perspective on 

Patuxent. I thank my more experienced advisors, especially 

Marshall Howe, Dick Jachowski, John Tautin, Dave Trauger, 

and Marilyn Whitehead (USGS). I acknowledge my longstanding and ever full of advice scientific colleagues at the 

USGS, Patuxent, especially Dick Banks, Paul Buckley, Mike 

Erwin, Mercedes Foster, Roy McDiarmid, Matt Perry, Barnett 

Rattner, Chan Robbins, and Melanie Steinkamp. I appreciate help in preparing this chapter from Dick Banks, Harry 

Coulombe, Matt Perry, Bruce Peterjohn, Bob Reynolds, John 

Tautin, and Marilyn Whitehead (USGS, Patuxent).

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J.E., Syderman, Bill, Trapp, John, Wheeler, Jennifer, and 

Wohl, Kent, 2002, Waterbird conservation for the Americas—The North America Waterbird Conservation Plan 

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Daniel, Pollock, Ken, Smith, C.R., Trapp, J.L., and Welling, 

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Perry, M.C., 2016, Patuxent’s development—The people and 

the projects, in Perry, M.C., ed., The history of Patuxent—

America’s wildlife research story: U.S. Geological Survey Circular 1422, p. 1–12. [Also available at https://doi.

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part 1: Wildlife Society Bulletin, v. 26, no. 2, p. 199–202. 

[Also available at http://www.jstor.org/stable/3784037.]

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p. 95–98.

Robbins, C.S., 2016, Early avian studies at Patuxent, in

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wildlife research story: U.S. Geological Survey Circular 

1422, p. 13–24. [Also available at https://doi.org/10.3133/

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whoop2.htm. 

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Tautin, John, eds., Bird banding in North America—The 

first 100 years: Cambridge, MA, Memoirs of the Nuttall 

Ornithological Club, no. 15, p. 65–91.

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for and collaboration with research at Patuxent, in Perry, 

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Other Programs at Patuxent

Facility and Research Initiatives at Patuxent 

for the New Millennium

Judd A. Howell

The Challenge

When I came to Maryland in 2002, I realized facilities 

at the Patuxent Wildlife Research Center (Patuxent) had been 

allowed to languish for several decades due to flat budgets and 

more important research priorities (CTA Architects Engineers 

[2000] and Patuxent Joint Working Group [2003], unpub. 

reports available from the Patuxent Wildlife Research Center, 

Laurel, MD). During my interview for the position of director, 

two points became very clear to me: that I needed know about 

facilities and that I needed to know about leadership. Both 

would be the challenge during my tenure at Patuxent.

First Steps

Literally, the first step was to repair the brick steps 

leading to Merriam Laboratory. Bricks were falling out of 

the steps while yellow tape and orange cones restricted passage. The work eventually had to be redone by a mason who 

understood historic restoration, but the effort was symbolic. It 

was a simple job, certainly not the highest priority, but it was 

highly visible and represented safe passage for the people who 

worked in the building. The effort showed that something was 

going to be done. Step 2 required hiring a new facilities manager to stabilize the facilities situation at Patuxent while plans 

for its modernization could be completed.

By the time I arrived, a committee from the U.S. Geological Survey (USGS) and U.S. Fish and Wildlife Service 

(USFWS) had developed a facilities restoration plan with a 

cost of $120 million (Patuxent Joint Working Group, 2003, 

unpub. report available from the Patuxent Wildlife Research 

Center, Laurel, MD). Although the plan would completely 

restore both agencies’ infrastructure, the high price tag was an 

impediment to its adoption.

The Move

Having been at Patuxent for 8 months, I began to think 

about my first holiday message. I had been keeping staff 

informed about Patuxent activities with an informal message 

called “Thought from this Corner” (referring to my corner 

office), which I sent by e-mail periodically. In the third paragraph of the holiday thought, I discussed the need to abandon 

Stickel Laboratory, move perhaps to Beltsville Agricultural 

Research Center (BARC) in Beltsville, MD, and consolidate other personnel in Gabrielson Laboratory. Then I left 

for vacation.

By the time 2003 had begun, Patuxent was buzzing 

about the move. Patuxent had regular monthly meetings for 

all hands, including those at field stations. Generally, field station employees phoned in to listen and ask questions. By the 

time of the first Patuxent center-wide meeting of 2003, I had 

received many negative e-mails in response to the December 

“thought” regarding the possible move. The day of reckoning 

had arrived. While everyone assembled in the large conference room, I donned a highway safety vest and a hard hat, 

and drew a big red bull’s-eye that I taped to my chest. The 

sound emanating from the conference room as I approached 

resembled that produced by a hive of bees. I stood outside the 

door to let the excitement build and then I entered. The room 

suddenly went quiet, and then someone laughed, as did others. 

The room seemed to fill with smiles and grins.

I said, “Okay, we have some tough work to do, so go 

ahead and take your best shot.” I laid out the plan to move, 

dressed in vest, hardhat, and target. That bit of tomfoolery set 

the tone and lightened the mood. As a result, Patuxent worked 

through the tough details of abandoning Stickel Laboratory, 

moving out of Merriam and Nelson Laboratories, and relocating a third of the staff to BARC. The move was to be interim 

until new and renovated facilities were completed at Patuxent. Although some of the early sentiment was that this would 

destroy the unity of Patuxent, the spirit of the people remains 

the core of what makes Patuxent a great research institution. After seeing the completed upgrade of the Beltsville 

Laboratory, one scientist even asked to be relocated there. 

I said no, that some of us needed to share the discomfort of 

crowded conditions until the entire restoration of Patuxent 

was completed.

New Blood, New Thrusts

In the face of more than 12 years of flat budgets and 

an older, retiring workforce, it was imperative that the next 

generation of great scientists at Patuxent be recruited. During 
250 The History of Patuxent: America’s Wildlife Research Story

Diann Prosser, U.S. Geological Survey, in Mongolia with swan goose 

instrumented with solar-powered transmitter, 2006. Photo by John Takekawa, 

U.S. Geological Survey.

Alicia Berlin, U.S. Geological Survey, weighing common eider in seaduck 

colony for selenium study at Patuxent Wildlife Research Center, Laurel, MD, 

2004. Photo by Matthew C. Perry, U.S. Geological Survey.

my tenure, I oversaw the hiring of a research zoologist, 

Terry Chesser, at the National Museum of Natural History; 

a research statistician, Andy Royle, and a research ecologist, Sarah Converse, for the quantitative methods group at 

Patuxent; a research ecologist, Natalie Karouna-Renier, for 

the contaminants group; and a statistician, Clint Moore, for 

quantitative methods at the Athens, GA, field station. Wildlife 

biologist Mark Wimer was hired full time for the Breeding 

Bird Survey, and wildlife biologist Monica Tomosy became 

the new chief of the Bird Banding Laboratory (BBL), which 

was transformed and reengineered under her leadership, with 

the assistance of the computer scientist, Kevin Laurent, and 

the Herculean efforts of the BBL staff.

Two Student Career Experience Program Ph.D. students 

who worked at Patuxent during my tenure stand out. Alicia 

Berlin, under the direction of research biologist Matthew 

Perry, completed her dissertation about seaducks using Patuxent’s newly constructed seaduck dive tanks. Diann Prosser, 

under the direction of research biologist Michael Erwin, 

opened the research door to China, working with the Chinese 

Academy of Sciences and John Takekawa at the Western 

Ecological Research Center, Sacremento, CA, on a project to 

study the transmission of highly pathogenic avian influenza, 

H5N1, in migratory birds. These young and brilliant minds 

along with their exceptional, more experienced colleagues will 

most likely keep Patuxent in the forefront of wildlife research 

for decades to come.

The Presidential Visit

On a Saturday morning, October 20, 2007, President 

Bush, First Lady Laura Bush, Secretary of the Interior Dirk 

Kempthorne, and the wife of the Secretary of the Treasury, 

Wendy Paulson, came to Patuxent to make a media announcement about conservation efforts for migratory birds. As part 

of the event, I had the opportunity to give them a tour of 

President George W. Bush and First Lady Laura Bush near the crane pens at 

the Patuxent Wildlife Research Center, Laurel, MD, 2007. Photo by Eric Draper, 

White House photographer.
Other Programs at Patuxent

Facility and Research Initiatives at Patuxent for the New Millennium 251

First Lady Laura Bush, Secretary of the Interior Dirk Kempthorne, President Bush, Bradley A. Knudsen, and Judd A. Howell at Cah Lake, Patuxent Wildlife 

Research Center, Laurel, MD, 2007. Photo by Eric Draper, White House photographer.

Patuxent’s Endangered Species Program facilities, especially 

the whooping cranes. What flashed through my mind was, 

“How do I tell the Secretary in 60 seconds how and why we 

need $82 million for the rehabilitation of Patuxent?”

I looked at my watch and said that there probably was 

not enough time, because the group had to move on. Instead, I 

asked the Secretary whether I could come to his office to have 

that discussion. The Secretary said that would be fine. We then 

proceeded with our tour.

The next event was the media event. Patuxent Research 

Refuge Manager Bradley A. Knudsen escorted the entourage 

along the lake to see wildlife, and then they headed back to 

the podium for the announcement, which included direction to the Secretary to add funds to the National Wildlife 

Refuge system (http://georgewbush-whitehouse.archives.

gov/news/releases/2007/10/20071020-2.html, accessed 

December 30, 2015).

Winter Weather and Cranes

One defining moment for Patuxent and the Refuge was 

the heavy, wet snow in February 2006. That snow crushed 105 

of the 110 whooping crane breeding pens. The last time that 

had happened was in the mid-1980s, and the breeding season 

had been lost. My management team and I mobilized the 

resource, with exceptional help from the Patuxent and Refuge 

staffs. In a mere 3 weeks, this highly focused, hands-on effort 

restored the pens to operation. The Friends of Patuxent, a 

volunteer support group for Patuxent, supplied the funds for 

the food. Director’s Office staff members Marilyn Whitehead 

and Regina Lanning acted as chiefs for the “Crane Cafe” that 

fed the volunteers in the field for the long hours of labor. That 

year Patuxent successfully reared 17 whooping cranes to be 

released into the wild. The event brought the entire Patuxent 

community together in a spirit of common cause that I will 

never forget.

The Final Plan

With the considerable work from all levels of the USGS 

and the USFWS, the final $82 million restoration plan for 

Patuxent had been elevated to the number 1 priority for funding by the Department of the Interior. Senate Appropriations 

staffers had outlined the best approach for a funding schedule. 

Water and sewer lines were connected to the local water and 

treatment district, and design concepts began to be formulated. It was a possible start for a new Patuxent. In June 2008, 

I retired and returned to California.
252 The History of Patuxent: America’s Wildlife Research Story

Judd A. Howell, U.S. Geological Survey, and his wife, Nancy Howell, with 

President George W. Bush in the White House Oval Office, 2007. Photo by Eric 

Draper, White House photographer.
Appendix 1. Contributors and Contact 

Information, September 2016.
254 The History of Patuxent: America’s Wildlife Research Story

Name Affiliation Title Mailing address

Lowell W. Adams University of 

Maryland

Associate Professor (retired) Department of Environmental Science and Technology, University of 

Maryland, College Park, MD 20742

Ralph Andrews USFWS Chief, Wetland Ecology 

Section (retired)

U.S. Fish and Wildlife Service, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

Robert J. Blohm USFWS Migratory bird biologist 

(retired)

Division of Migratory Bird Management, U.S. Fish and Wildlife 

Service, 12100 Beech Forest Road, Laurel, MD 20708

Nancy C. Coon USFWS Branch Chief, Technical 

Services (retired)

U.S. Geological Survey, Patuxent Wildlife Research Center, 12100 

Beech Forest Road, Laurel, MD 20708

Richard A. Coon USFWS Program Manager, Migratory 

Bird and Habitat Research 

Laboratory (retired)

U.S. Geological Survey, Patuxent Wildlife Research Center, 12100 

Beech Forest Road, Laurel, MD 20708

R. Michael Erwin PWRC Emeritus Senior Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, 

Department of Environmental Sciences, Clark Hall, University of 

Virginia, Charlottesville, VA 22904

Lynda J. Garrett PWRC Librarian (retired) U.S. Geological Survey, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

Russell J. Hall PWRC Deputy Director (retired) U.S. Geological Survey, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

Gary H. Heinz PWRC Emeritus Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

Charles J. Henny PWRC Emeritus Scientist U.S. Geological Survey, Forest and Rangeland Ecosystem Science 

Center, 777 NW 9th Street, Suite 400, Corvallis, OR 97330

Judd A. Howell PWRC Director (retired) H.T. Harvey & Associates, Ecological Consultants, 983 University 

Avenue, Building D, Los Gatos, CA 95032

Cameron B. Kepler PWRC Emeritus Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, Athens 

Field Station, The University of Georgia, Warnell School of 

Forestry and Natural Resources, Athens, GA 30602

Bradley A. Knudsen USFWS Refuge Manager U.S. Fish and Wildlife Service, Patuxent Research Refuge, 

10901 Scarlet Tanager Loop, Laurel, MD 20708

James A. Kushlan PWRC Director (retired) P.O. Box 2008, Key Biscayne, FL 33149

Jerry R. Longcore PWRC Emeritus Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, 

Maine Field Station, 151 Bennoch Road, Orono, ME 04473

L. David Mech PWRC Senior Research Scientist U.S. Geological Survey, Northern Prairie Wildlife Research Center, 

8711 37th Street, SE, Jamestown, ND 58401

Appendix 1. Contributors and contact information, September 2016.

[USFWS, U.S. Fish and Wildlife Service; PWRC, U.S. Geological Survey Patuxent Wildlife Research Center]
Appendix 1 255

Name Affiliation Title Mailing address

Glenn H. Olsen PWRC Emeritus Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

Matthew C. Perry PWRC Emeritus Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

Barnett A. Rattner PWRC Research Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

Chandler S. Robbins PWRC Emeritus Senior Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

John R. Sauer PWRC Research Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

J. Michael Scott USFWS Hawaii project leader 

(retired)

Department of Fish and Wildlife, University of Idaho, Moscow, 

ID 83844

Glen Smart USFWS Research biologist (retired) U.S. Fish and Wildlife Service, Patuxent Wildlife Research Center, 

12100 Beech Forest Road, Laurel, MD 20708

Noel F.R. Snyder USFWS California condor project 

leader (retired)

P.O. Box 16426, Portal, AZ 85632 

Donald W. Sparling USFWS Research scientist Cooperative Wildlife Research Laboratory, Southern Illinois 

University Carbondale, 251 Life Science II, Carbondale, IL 62901

Paul W. Sykes, Jr. PWRC Emeritus Scientist U.S. Geological Survey, Patuxent Wildlife Research Center, Athens 

Field Station, The University of Georgia, Warnell School of 

Forestry and Natural Resources, Athens, GA 30602

John Tautin PWRC Chief, Bird Banding 

Laboratory (retired)

Purple Martin Conservation Association, 301 Peninsula Drive, 

Suite 6, Erie, PA 16505

James W. Wiley PWRC Caribbean project leader 

(retired)

P.O. Box 64, Marion Station, MD 21838

Appendix 1. Contributors and contact information, September 2016.—Continued

[USFWS, U.S. Fish and Wildlife Service; PWRC, U.S. Geological Survey Patuxent Wildlife Research Center]

Publishing support provided by the 

U.S. Geological Survey Science Publishing Network, 

West Trenton and Rolla Publishing Service Centers 

For more information concerning the research in this report, contact:

Director, Patuxent Wildlife Research Center

U.S. Geological Survey

12100 Beech Forest Road

Laurel, MD 20708

http://www.pwrc.usgs.gov/
Perry, ed.—The History of Patuxent: America’s Wildlife Research Story—Circular 1422

ISSN 1067-084X (print)

ISSN 2330-5703 (online)

https://doi.org/10.3133/cir1422