RESTORATION OF COMMON MURRE COLONIES IN CENTRAL CALIFORNIA:

ANNUAL REPORT 2004

REPORT TO THE APEX HOUSTON TRUSTEE COUNCIL

Gerard J. McChesney1

, Nathan M. Jones2, Travis B. Poitras2, Karen J. Vickers2, Lisa E. Eigner2, Harry R. Carter3

, Richard T. Golightly2, Stephen W. Kress4, Michael W. Parker5, Kristina Studnicki2

, Phillip J. Capitolo2, and James N. Hall2

U.S. Fish and Wildlife Service

San Francisco Bay National Wildlife Refuge Complex

 P.O. Box 524

Newark, CA 94560

FINAL REPORT

 1 August 2005
RESTORATION OF COMMON MURRE COLONIES IN CENTRAL CALIFORNIA:

ANNUAL REPORT 2004

REPORT TO THE APEX HOUSTON TRUSTEE COUNCIL

by

Gerard J. McChesney1

, Nathan M. Jones2, Travis B. Poitras2, Karen J. Vickers2, Lisa E. Eigner2, Harry R. Carter3

, Richard T. Golightly2, Stephen W. Kress4, Michael W. Parker5, Kristina Studnicki2

, Phillip J. Capitolo2, and James N. Hall2

 1U.S. Fish and Wildlife Service, San Francisco Bay National Wildlife Refuge Complex,

 P.O. Box 524, Newark, CA 94560

2

Humboldt State University, Department of Wildlife, Arcata, CA 95521 3

Carter Biological Consulting, 1015 Hampshire Road, Victoria, BC V8S 4S8 Canada

 4National Audubon Society, 159 Sapsucker Road, Ithaca, NY 14850 5

U.S. Fish and Wildlife Service, Red Rock Lakes National Wildlife Refuge,

27820 Southside Centennial Road; Lima, MT 59739

U.S. Fish and Wildlife Service

San Francisco Bay National Wildlife Refuge Complex

 P.O. Box 524

Newark, CA 94560

FINAL REPORT

 1 August 2005
ii

Suggested Citation: McChesney, G. J., N. M. Jones, T. B. Poitras, K. J. Vickers, L. E.

Eigner, H. R. Carter, R. T. Golightly, S. W. Kress, M. W. Parker,

K. Studnicki, P. J. Capitolo, and J. N. Hall. 2005. Restoration of

Common Murre colonies in central California: annual report 2004.

Unpublished report, U.S. Fish and Wildlife Service, San Francisco

Bay National Wildlife Refuge Complex, Newark, California

(prepared for the Apex Houston Trustee Council).
iii

TABLE OF CONTENTS

LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv

LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix

PROJECT STRUCTURE AND ADMINISTRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi

INTRODUCTION ............................................................1

SCIENTIFIC PROGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Social Attraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Monitoring Effort . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Seasonal Attendance Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Productivity - Common Murre . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Adult Time Budgets - Common Murres ..................7

Disturbance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Brandt’s Cormorant Productivity and Nest Surveys . . . . . . . . 8

Aerial Photographic Surveys . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Colony Surveys - Other Species . . . . . . . . . . . . . . . . . . . . . . . . . 9

RESULTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Social Attraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Seasonal Attendance Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Productivity - Common Murre . . . . . . . . . . . . . . . . . . . . . . . . . 12

Adult Time Budgets - Common Murres . . . . . . . . . . . . . . . . . 13

Disturbance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Brandt’s Cormorant Productivity and Nest Surveys . . . . . . . 16

Aerial Photographic Surveys . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Colony Surveys - Other Species . . . . . . . . . . . . . . . . . . . . . . . . 18

DISCUSSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

ENVIRONMENTAL EDUCATION PROGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

PARTICIPANTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

TEACHER RESOURCE MATERIALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

DECOY CLEANING AND REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

CLASSROOM PRESENTATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Initial Visits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Final visits (Painting Decoys) . . . . . . . . . . . . . . . . . . . . . . . . . . 24

CLASSROOM EXTENSION ACTIVITIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

EDUCATION PROGRAM SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

LITERATURE CITED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

APPENDIX 1. Raw counts of Common Murre birds, and Brandt’s and Double-crested

cormorant nests, sites and birds from aerial photographic surveys of central California

colonies, 2004. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
iv

LIST OF FIGURES

Figure 1. Map showing the location of the two study sites along the central California coast.

Devil’s Slide Rock and San Pedro Rock are located within the Devil’s Slide

Colony Complex.

Figure 2. Devil’s Slide Colony Complex including colonies and subcolonies monitored by

the Common Murre Restoration Project.

Figure 3. Castle/Hurricane Colony Complex, including Bench Mark-227X (BM227X),

Castle Rocks and Mainland (CRM), and Hurricane Point Rocks (Hurricane).

Labels indicate subcolonies mentioned in the text.

Figure 4. GIS map of Devil’s Slide Rock, 2004. Common Murre breeding and territorial

sites are shown in relation to social attraction equipment.

Figure 5. Photograph of Common Murre and Brandt’s Cormorant decoys on San Pedro

Rock.

Figure 6. San Pedro Rock (south side) as it appears from the viewing location along

Highway 1. The rock is divided into five sections for recording bird and marine

mammal locations (West End, East End, Lower, The Nose, Decoy Area).

Figure 7. Number of Common Murre breeding and territorial sites at Devil's Slide Rock,

1996-2004.

Figure 8. Number of Common Murre breeding and territorial sites within and outside of

decoy plots on Devil's Slide Rock, 1996-2004.

Figure 9. Seasonal attendance of Common Murres at Devil's Slide Rock, 11 November

2003 to 11 August 2004. Attendance is reported as an average of three

consecutive counts. Dashed line indicates pre-season (prior to 16 April).

Figure 10. Seasonal attendance of Common Ravens and Common Murres at San Pedro

Rock, 17 April to 31 July 2004. Data are recorded as an average number of birds

seen per 10 minute scan during two hour watches.

Figure 11. Seasonal Attendance patterns of Common Murres at BM227X subcolony 02

(Esselen), and Castle Rocks and Mainland subcolonies 02, 03 East, and 03 West,

8 April to 29 July 2004. Dashed line indicates attendance after arrival of the

juvenile Brown Pelican on 24 June (see Disturbance).

Figure 12. Seasonal attendance patterns of Common Murres at Castle Rocks and Mainland

subcolonies CRM 04, 05 and 07, 8 April to 29 July 2004. Dashed line indicates

attendance after arrival of the juvenile Brown Pelican on 24 June (see

Disturbance).

Figure 13. Seasonal attendance patterns of Common Murres at Hurricane Point Rocks

subcolonies 01, 02 Ledge, and 02 Hump, 8 April to 29 July 2004. Dashed line

indicates attendance after arrival of the juvenile Brown Pelican on 24 June (see

Disturbance).

Figure 14. Survey areas from boat survey of seabird colonies in the San Pedro Rock to

Devil’s Slide areas, 18 June 2004.
v

Figure 15. Aerial overview photograph of Devil’s Slide Rock, 3 March 2004. 

Figure 16. Aerial overview photograph of Devil’s Slide Rock, 25 May 2004.

Figure 17. Prospecting Common Murre among decoys on San Pedro Rock, 21 June 2004. 

Figure 18. Pair of Common Ravens attracted to mirrors on San Pedro Rock, 6 June 2004.

Figure 19. View to southwest from Castle Pullout of raven nesting cliff at Castle Mainland,

2004. Arrow indicates approximate location of nest.

Figure 20. Common Raven with a murre egg, Castle Rocks subcolony 04, May 2004.

Figure 21. “Right” side of CRM-04 productivity plot, 12 June 2004.

Figure 22. Juvenile Brown Pelican on “right” side of CRM-04 productivity plot during

disturbance event, late June 2004. Note the murre chick near the pelican’s tail. 
vi

LIST OF TABLES

Table 1. Common Murre productivity at Devil’s Slide Rock (DSR) and Castle Rocks and

Mainland (CRM), 2004.

Table 2. Non-anthropogenic disturbances incidentally observed at the Castle/Hurricane

Colony Complex, 2004. Data listed includes: mean number and range of

murres/eggs/chicks disturbed or lost per event, and the number of events.

Table 3. Common Murre egg and chick loss on Castle Rocks and Mainland, subcolony 04

during Brown Pelican disturbances, 24 June to 2 July 2004.

Table 4. Aircraft sightings, boat sightings, and resulting disturbances incidentally observed

at Devil’s Slide Rock, 2004.

Table 5. Brandt’s Cormorant breeding phenology and reproductive success at Devil’s

Slide Rock and Mainland, 2004.

Table 6. Numbers of Brandt’s Cormorant poorly-built nests (PBN), fairly-built nests

(FBN), and well-built nests (WBN) counted at the Devil’s Slide Rock and

Mainland colony, 2004.

Table 7. Table 7. Numbers of Brandt’s Cormorant poorly-built nests (PBN), fairly-built

nests (FBN), and well-built nests (WBN) counted at the Castle/Hurricane Colony

Complex, 2004. Not all subcolonies were counted on each day.

Table 8. Summary of aerial photograph counts of Common Murres (COMU), Brandt’s

Cormorants (BRCO), and Double-crested Cormorants (DCCO) at sample central

California breeding colonies, 2004.

Table 9. Numbers of Pelagic Cormorants, Western Gulls, Pigeon Guillemots, and Black

Oystercatchers counted at breeding colonies on a boat survey between San Pedro

Rock and Pillar Point, 18 June 2004. ND, no data.

Table 10. Numbers of Pelagic Cormorant, Western Gull, and Black Oystercatcher nests and

Pigeon Guillemot birds counted at the Castle/Hurricane Colony Complex, 2004.
vii

ACKNOWLEDGMENTS

The Apex Houston Common Murre Restoration Project is conducted cooperatively by the U.S.

Fish and Wildlife Service, San Francisco Bay National Wildlife Refuge Complex (USFWSSFBNWRC), Humboldt State University (HSU), the National Audubon Society (NAS), and

other public and private organizations, with oversight by the Apex Houston Trustee Council

(made up of USFWS, National Oceanic and Atmospheric Administration [NOAA], and

California Department of Fish and Game [CDFG]).

Special thanks go to the Apex Houston Trustee Council for their unwavering support throughout

the project: Dan Welsh (USFWS-Ecological Services), Maria Brown (NOAA-Gulf of the

Farallones National Marine Sanctuary [GFNMS]), Paul Kelly (CDFG-Office of Spill Prevention

and Response [OSPR]), Jennifer Boyce (NOAA alternate representative), Joelle Buffa (USFWS

alternate representative). Thanks are also due to Carolyn Lown (Department of the InteriorOffice of the Solicitor) for legal advice and assistance with landowner agreements.

Many other individuals and organizations have helped to make this project a great success

through their support and hard work. Departing crew members A. Robinson and J. Koepke

(HSU) assisted greatly with decoy removal, decoy deployment, winter observations, field season

preparation, and training new field biologists. Special thanks to Marge Kolar (Refuge Complex

Manager) and all the other staff and volunteers of the USFWS-SFBNWRC for their constant

support and assistance, especially: Sheila Baham, Joelle Buffa, Tess Dumaop, Juan Flores, Diane

Kodama, Danielle Le Fer, Clyde Morris, Ellen Tong, and Larry Wade; Betty Foster for her

continued assistance with decoy repairs; Ken Clarkson for his assistance with the education

component of the restoration project; and Joelle Buffa, Rachel Hurt, Jesse Irwin, Marc Mitchell,

Sally Reynolds, and Natalie Wilson for their assistance with decoy deployment or removal. We

sorely missed Beverly Drollman this year, whom assisted with decoy repairs for several years. 

Many thanks to Kirstin Bixler for all of her volunteer assistance on many aspects of the project. 

Other assistance on system deployment and removal was provided by Eli Bernstein, Alex

Genevsky, John Mason, Laura Pavliscak, Amy Whitesides, and Rich Young. In addition, the

many students and teachers of our Education Program deserve special thanks for all their efforts

repainting our decoys.

Rheannon Okey and Talitha Penland from the Department of Wildlife, HSU, as well as Joe

Bonino and the staff at the HSU Foundation, deserve special thanks for assisting the project with

their administrative efforts. 

Special thanks to pilots Wayne Burnett, Larry Heitz, and Robert Morgan (CDFG- Air Services)

for their continued support, expertise and safety on our aerial seabird surveys. Many thanks to

Paul Kelly (CDFG-OSPR) for his continued support of these surveys.

Thanks also to: Julie Yee and Bill Perry (U.S. Geological Survey, Western Ecological Research

Center); Rose Borzik (National Audubon Society Seabird Restoration Project); Jan Roletto

(NOAA-GFNMS); Deirdre Hall and Scott Kathey (NOAA, Monterey Bay National Marine

Sanctuary); Daniel Zatz, Lane Chesley, and Matt Pawuk (SeeMore Wildlife Systems); Carter

Stewart (U.S. Department of Justice); Brian Popper (USDA-Wildlife Services); Mike Hink and

Jack Van Zander (Bestor Engineers); Bill Sydeman, Russell Bradley, and Pete Warzybok (Point

Reyes Bird Observatory); Sue Schubel (Murremaid Music Boxes); and Roger Helm (USFWS). 

Very special thanks to Armand and Elaine Neukermans for permission to access their Big Sur

property. The views afforded from this coastal location assisted greatly with our monitoring of

murres at Castle Rocks and Mainland.

Aerial survey work in the Gulf of the Farallones and Monterey Bay National Marine Sanctuaries

were conducted under a permit from NOAA (permit GFNMS/MBNMS-2000-003-G). 
viii

Observations of Devil’s Slide Rock and San Pedro Rock were conducted from the mainland

under Encroachment Permit No. 0403-NSV0720 from the California Department of

Transportation. 

Field site monitoring for the Common Murre Restoration Project in 2004 was conducted mainly

by: N. Jones, K. Vickers, and L. Eigner (Devil’s Slide Rock and Mainland, San Pedro Rock);

and T. Poitras (Castle/Hurricane Colony Complex). The Education Program was run by K.

Studnicki. Aerial surveys were conducted by G. McChesney and P. Capitolo, with assistance

from N. Jones and J. Buffa. Counting of seabirds from aerial photographs was conducted mainly

by N. Jones, K. Vickers, E. Eigner, T. Poitras, P. Capitolo, and J. Hall. 
ix

EXECUTIVE SUMMARY

The 1986 Apex Houston oil spill off the central California coast killed approximately 9,900

seabirds, including 6,300 Common Murres (Uria aalge). A litigation settlement in August 1994

provided funding for restoration of natural resources injured by the oil spill. To oversee the

implementation of restoration actions, the Apex Houston Trustee Council (AHTC) was

established and comprised of representatives from the U.S. Fish and Wildlife Service, California

Department of Fish and Game, and National Oceanic and Atmospheric Administration. Three

restoration projects have been approved to date: 1) the Common Murre Restoration Project; 2)

the Marbled Murrelet (Brachyramphus marmoratus) Nesting Habitat Acquisition Project; and 3)

seabird habitat restoration at the South Farallon Islands (Farallon National Wildlife Refuge).

The U.S. Fish and Wildlife Service (San Francisco Bay National Wildlife Refuge Complex;

hereafter "Refuge") was selected by the AHTC to lead the Common Murre Restoration Project. 

Soon after the preparation of a publicly reviewed restoration plan the Refuge created the

scientific and environmental education programs which constitute the Common Murre

Restoration Project. Field data collection and analysis for the scientific aspect of the project is

being conducted by biologists from the Refuge in collaboration with the U.S. Fish and Wildlife

Service (Ecological Services), Humboldt State University, and National Audubon Society. 

Additional assistance has been by: Carter Biological Consulting, U.S. Geological Survey, Point

Reyes Bird Observatory, National Park Service (Point Reyes National Seashore), Gulf of the

Farallones and Monterey Bay National Marine Sanctuaries, California Department of Fish and

Game, and the California Department of Transportation. The Refuge is also playing the lead role

in the implementation of the environmental education program. This report summarizes the

results for year nine (Federal Fiscal Year 2004) of the scientific and environmental education

programs which make up the Common Murre Restoration Project.

Efforts to restore the Common Murre colonies at Devil’s Slide and San Pedro rocks using social

attraction equipment began in 1996 and 1998, respectively, and and have continued since then. 

At Devil’s Slide Rock on 5 March 2004, 112 adult murre decoys were re-deployed and the sound

system turned back on. Social attraction equipment was re-deployed on San Pedro Rock on 10

February 2004, including: 188 murre adult, 19 chick, and 15 egg decoys; 18 standing and 24

incubating (on decoy nests) cormorant decoys; and the sound system turned back on. Two

remote video cameras were reinstalled on San Pedro Rock to assist monitoring efforts. At

Devil’s Slide Rock, the decoys were removed following the breeding season to be cleaned and

re-painted and sound systems were turned off. All equipment was permanently removed from

San Pedro Rock.

Besides the social attraction work, information associated with Common Murre breeding and

population ecology, as well as information concerning human and natural disturbances, was

collected at Devil’s Slide Rock, San Pedro Rock and at the Castle/Hurricane Colony Complex as

in previous years. Point Reyes Headlands, which was monitored from 1996 to 2002, was not

monitored in 2004. Parameters monitored included: seasonal attendance patterns, colony and

subcolony population sizes, breeding phenology, reproductive success, and adult time budgets. 

Also, data on Brandt’s Cormorant (Phalacrocorax penicillatus) attendance and productivity

were collected. In addition, aerial photographic surveys of Common Murre, Brandt’s

Cormorant, and Double-crested Cormorant (P. auritus) colonies were conducted in northern and

central California. These surveys showed higher numbers of all three species at most central

California colonies counted in 2004 compared to 2003. All information collected is used to help

evaluate and refine restoration efforts at Devil’s Slide Rock, San Pedro Rock, Castle/Hurricane

Colony Complex, and other colonies in central California where restoration may be needed. 

This information is helping us gain a better understanding of Common Murre breeding and

population biology, as well as the impacts of human and natural disturbances on murres in

central California.
x

Efforts of the Scientific Program resulted in 190 pairs of murres nesting and 133 chicks fledging

from Devil’s Slide Rock (DSR) in 2004, an increase of 80 nesting pairs and 63 fledged chicks

from the 2003 breeding season. This was the fourth consecutive year of exceeding the 10-year

project goal of 100 breeding pairs of murres on DSR, first obtained in year six (2001) of

restoration efforts. For the seventh consecutive year since social attraction techniques began at

San Pedro Rock, no breeding occurred and murre attendance was low, leading to the

discontinuation of efforts there following the 2004 season. Murre plots monitored at

Castle/Hurricane Colony Complex experienced almost complete breeding failure in 2004 due to

raven and pelican disturbance and predation.

The Environmental Education Program continued for the ninth consecutive year in 2004. The

program focused on teaching students about: 1) the natural history and adaptations of Common

Murres; 2) the detrimental impacts humans have had on central California murres from the 1800s

to the present; 3) efforts to restore Common Murres in central California; and 4) ways students

can help restore and protect seabirds. The project also provided students with the opportunity to

participate in the restoration project at Devil’s Slide Rock by repainting the murre decoys before

their re-deployment. Personnel from this year’s education outreach program taught

approximately 880 students from nine San Francisco Bay Area schools about the conservation

issues impacting seabirds in the student’s local area and around the world.
xi

PROJECT STRUCTURE AND ADMINISTRATION - 2004

TRUSTEE COUNCIL

U.S. Fish and Wildlife Service

Daniel Welsh, Primary Representative, Sacramento Fish and Wildlife Office (Council

Leader)

Joelle Buffa, Alternate Representative, San Francisco Bay National Wildlife Refuge

Complex

 

National Oceanic and Atmospheric Administration

Maria Brown, Primary Representative, Gulf of the Farallones National Marine Sanctuary

Jennifer Boyce, Alternate Representative, NOAA Restoration Center 

California Department of Fish and Game, Office of Spill Prevention and Response

Paul Kelly, Primary Representative, Sacramento Office

U.S. FISH AND WILDLIFE SERVICE, SAN FRANCISCO BAY NATIONAL WILDLIFE

REFUGE COMPLEX

Margaret Kolar, Refuge Complex Manager

Gerard McChesney, Wildlife Biologist (Principal Investigator)

HUMBOLDT STATE UNIVERSITY

Richard Golightly, Department of Wildlife, Professor (Principal Investigator)

NATIONAL AUDUBON SOCIETY

Steve Kress, Seabird Restoration Program (Scientific Advisor)

CARTER BIOLOGICAL CONSULTING

Harry Carter (Biologist, Scientific Advisor)

U.S. FISH AND WILDLIFE SERVICE, RED ROCK LAKES NATIONAL WILDLIFE

REFUGE

Michael Parker, Refuge Complex Manager (Scientific Advisor and past Principal

Investigator)
1

INTRODUCTION

Common Murre (Uria aalge) colonies in central California occur on certain nearshore rocks and

adjacent mainland points between Marin and Monterey counties as well as at the North and

South Farallon islands, 20 to 40 kilometers offshore (Carter et al. 1992, 1996, 2001). Trends in

this population of murres at all colonies have been well-documented since 1979 (Sowls et al.

1980; Briggs et al. 1983; Ainley and Boekelheide 1990; Takekawa et al. 1990; Carter et al. 1992,

1995, 2001; Sydeman et al. 1997; McChesney et al. 1998, 1999). A steep decline in the central

California population between 1980 and 1986 is attributed primarily to mortality in gill nets and

oil spills, including the 1986 Apex Houston oil spill (Page et al. 1990; Takekawa et al. 1990;

Carter et al. 2001, 2003b). Between 1982 and 1986, a colony of close to 3,000 breeding murres

on Devil’s Slide Rock in northern San Mateo County was extirpated by these mortality events. 

Since 1996, the Common Murre Restoration Project has sought to restore this and other central

California colonies using social attraction and other techniques. Social attraction has been

utilized at Devil’s Slide Rock and nearby San Pedro Rock, which was extirpated in the early

20th century primarily by commercial egg harvesters (Ray 1909, Carter et al. 2001). Efforts at

other colonies, especially the Castle/Hurricane Colony Complex, have focused mainly on

reducing anthropogenic disturbance and mortality factors.

Since 1989, murre breeding populations in central California have increased. The rate of

increase for the total population was estimated at 5.9% per annum between 1985-1995 (Carter et

al. 2001). This partial recovery of the central California Common Murre population has been

attributed to a series of gill-net fishing closures that have occurred in central California since

1982, as well as reduced oiling from 1986-1995 (Carter et al. 2001). Despite population

increases, Devil’s Slide Rock was not recolonized by 1995 and most colonies remained in a

reduced state. Until more extensive gill-net closures (<60 fathoms from Point Reyes to Point

Arguello) were enacted by California Department of Fish and Game in September 2002, gill-net

mortality of murres continued through at least 2000 (Forney et al. 2001; National Marine

Fisheries Service, unpubl. data). In addition, oil pollution (e.g., Command Oil Spill, and the

series of oil releases from the sunken vessel S.S. Jacob Luckenbach) has continued to kill

thousands of murres in central California (Carter 2003, Carter and Golightly 2003, Hampton et

al. 2003, Roletto et al. 2003) and anthropogenic disturbance has affected colonies as well

(USFWS, unpubl. data).

The Apex Houston Oil Spill

Between 28 January and 4 February 1986, the barge Apex Houston discharged approximately

20,000 gallons of San Joaquin Valley crude oil while in transit from San Francisco Bay to the

Long Beach Harbor. Between Sonoma and Monterey counties, an estimated 9,900 seabirds were

killed, of which approximately 6,300 were Common Murres (Page et al. 1990, Carter et al.

2003b). The murre colony at Devil’s Slide Rock (DSR) was subsequently abandoned

(Takekawa et al. 1990; Carter et al. 2001, 2003b).

In 1988, state and federal natural resource trustees began litigation against potentially

responsible parties. In August 1994, the case was settled in a Consent Decree for $6,400,000. 

The Apex Houston Trustee Council, with representatives from California Department of Fish and

Game (CDFG), National Oceanic and Atmospheric Administration (NOAA), and U.S. Fish and

Wildlife Service (USFWS), was given the task of overseeing restoration actions for natural

resources injured by the spill. The amount of $4,916,430 was assigned to USFWS for the

implementation of the Common Murre Restoration Project.

The Common Murre Restoration Project

In 1995, the Apex Houston Trustee Council developed a restoration plan consisting of a

Scientific Program and an Environmental Education Program for the Common Murre

Restoration Project (USFWS 1995a). Field work for the Scientific Program has been conducted

since 1996 by USFWS, San Francisco Bay National Wildlife Refuge Complex (hereafter
2

“Refuge”), in collaboration with the USFWS-Ecological Services (Sacramento Field Office),

Humboldt State University (HSU), and the National Audubon Society. Additional assistance has

been provided by: Carter Biological Consulting; CDFG; U.S. Geological Survey (Western

Ecological Research Center; USGS); Point Reyes Bird Observatory (PRBO); National Park

Service (Point Reyes National Seashore); National Oceanic and Atmospheric Administration

(NOAA; Gulf of the Farallones and Monterey Bay National Marine Sanctuaries); and California

Department of Parks and Recreation.

The primary goals of the Scientific Program are the restoration of extirpated Common Murre

colonies at Devil’s Slide and San Pedro rocks (Figures 1, 2). Social attraction was selected as

the best-available technique to be used to recolonize these rocks (Parker et al. 1997, Carter et al.

2003b) because of its effective use elsewhere in encouraging seabirds to recolonize extirpated

colonies (Kress 1983; Podolsky 1985; Kress and Nettleship 1988; Podolsky and Kress 1989,

1991; Schubel 1993).

In January 1996, social attraction equipment (murre decoys, mirror boxes, and two sound

systems) was deployed on DSR for the first time (Parker et al. 1997). Decoys have been

deployed in a similar manner each year since. Successful breeding was recorded in 1996 and the

number of breeding pairs increased each season up to 2002. Because of the continuous annual

growth of the DSR colony since 1996, the amount of social attraction equipment has been

reduced in recent years to provide additional breeding space within decoys areas. As the colony

grows over time, social attractants eventually will be phased out completely.

Common Murres have not been recorded breeding on San Pedro Rock (SPR) since 1908 (Ray

1909, Carter et al. 2001). No murres were detected on SPR during ground and boat observations

or aerial surveys conducted in 1979-1997 (Parker et al. 1997, 1998; Carter et al. 2001). Social

attraction equipment (adult, egg, and chick decoys, mirrors, and two sound systems) was first

deployed in April 1998 and small numbers of murres were observed among the decoys

thereafter. Social attraction equipment has been used each year since 1998 but breeding has not

occurred.

We also monitored murre colonies at Castle Rocks and Mainland (CRM), Hurricane Point Rocks

(HPR), and Bench Mark-227X, all located on the Big Sur coastline in Monterey County (Figures

1, 3). The CRM and HPR colonies were impacted by the Apex Houston spill and declined

afterwards (Carter et al. 2001, 2003b). By 1997, they had recovered to about 52% of their predecline numbers (McChesney et al. 1999). Information from the Castle/Hurricane Colony

Complex has allowed us to assess the necessity of restoration actions, as well as examine aspects

of breeding biology at these disjunct, southernmost colonies.

This report summarizes restoration and monitoring efforts conducted by the Common Murre

Restoration Project at DSR, SPR, CRM, HPR, and BM227X in 2004. Monitoring at these

colonies included collecting data similar to previous years on murre colony population sizes,

attendance patterns, productivity and nesting phenologies. Aircraft, vessel, and avian

disturbances are also summarized. We also report on Brandt’s Cormorant (Phalacrocorax

penicillatus) nesting phenology and productivity at DSR and Mainland, and nesting phenology

only at CRM. In addition, summaries of murre and cormorant counts from central California

aerial photographic surveys are provided.
3

SCIENTIFIC PROGRAM

METHODS

Social Attraction

Devil’s Slide Rock

On 5 March 2004, 112 adult murre decoys (98 standing, 14 incubating) were re-deployed and the

single solar-powered sound system turned back on (Figure 4). Decoys had been removed from

DSR on 16 September 2003 following the 2003 breeding season. Decoys were then cleaned and

repaired during the fall of 2003, using the same techniques employed in previous years (also see

Environmental Education, below).

The number of decoys deployed was 9.7% lower than in 2003 (N=124) and 71% lower than the

original plot design utilized in 1996-1998 (N=384 decoys). The placement and number of

standing-posture and incubating-posture decoys was determined based in part on the locations of

usable decoy rods previously placed on DSR, and murre breeding and territorial sites from

previous years. As in 2002-2003, the variable density plot treatment method was not utilized in

favor of a more site-by-site approach in an attempt to increase densities of nesting murres and

join some of the disjunct breeding groups on DSR. However, decoys were still placed mainly

within the original plot boundaries. Our strategies involved thinning the decoys in high-density

nesting areas and removing decoys from portions of the rock with no active breeding sites.

The largest reduction of decoys was in plot 7, where 5 fewer decoys were deployed than in 2003. 

The breakdown of the number of decoys placed in each plot is as follows: Plot 1, 18 decoys; Plot

2, 3 decoys; Plot 3, 7 decoys; Plot 4, 6 decoys; Plot 6, 13 decoys; Plot 7, 13 decoys; Plot 8, 17

decoys; Plot 9, 12 decoys; Plot 10, 10 decoys; and Plot 12, 13 decoys. 

As in 2003, uniquely painted wooden dowels 1.5 feet (0.46 m) in height were placed on existing

decoy rods in plots 1, 2, 3, 7, 9, 10 and 12 at or near former mirror locations to serve as

landmarks. One mirror box remained in plot 8. 

Monitoring and analysis of murre site locations on DSR was again enhanced this year through

the use of Geographic Information System (GIS) data collected in 2000 and 2001 (Parker et al.

2001, 2002). During the 2004 breeding season, new nest sites and decoys were added to the GIS

database by approximating their locations in the field based on previously mapped (by GPS)

sites and equipment. Additional verification was done using using high quality aerial

photographs taken during colony surveys on 25 May 2004 and additional GPS work following

the breeding season (see below). Numbers of breeding and territorial sites found within decoy

areas were compared to numbers outside decoy areas. Murres were considered to be in a decoy

area if they were within approximately one murre-width (about 15 cm, or six inches) of a decoy.

Following the 2004 breeding season, decoys were removed from DSR on 4 October for cleaning

and repainting. At this time, the sound system was still turned on but one speaker had been

disconnected from the system and the other was emitting only static. It is unknown how long the

system had been in this condition, but we suspect that the one speaker had the cable

disconnected by a cormorant during the nest building stage in April-May. Also, several decoys

and wooden dowels had been lost from the rock for unknown reasons.

GPS data collection

During decoy removal on 4 October 2004, additional GPS work was conducted to update the

existing GIS database. GPS data collection was conducted by M. Hink (Bestor Engineers) and

W.M. Perry (U.S. Geological Survey). The GPS locations of existing decoys (standing,

incubating, standing but fallen) and wooden dowels were obtained, as well as locations of all
4

breeding and territorial sites used during the 2004 breeding season. The estimation of site

locations was collaborated by the three wildlife technicians that monitored DSR in 2004 (Jones,

Vickers, and Eigner), with Vickers on the rock and Jones and Eigner viewing from the principal

mainland viewing points at the “Traditional DSR Pullout” (Jones) and “The Bunker” (Eigner). 

Locations of existing decoys, dowels, mirror, and other natural features were used to determine

murre site locations.

Following GPS data collection, locations of equipment and murre sites that had been

approximated during the field season were updated on the 2004 GIS map. Locations of decoys

and dowels lost prior to GPSing were re-evaluated and changed if necessary. Although GPS

provided a more accurate description of the rock, we found little difference in locations of

decoys or murre sites before and after GPSing.

San Pedro Rock

On 10 February 2004, 188 adult, 19 chick, and 15 murre egg decoys were re-deployed on SPR,

and one of the two sound systems playing murre calls was turned on. Decoys were attached to

existing rods already in place throughout the various decoy plots or placed on newly placed rods

where necessary. The mirrors in the mirror boxes were turned around to reveal their reflective

sides, which had been turned the other way since early 2002 (Knechtel et al. 2003) because of

Common Raven (Corvus corax) attraction to the mirrors. However, mirrors were again turned

around on 18 June 2004 to show their non-reflective sides because of renewed raven activity at

the mirrors.

As in 2003 we deployed Brandt’s Cormorant decoys in addition to the murre decoys. It has been

documented that murres tend to establish new breeding sites in areas where these cormorants

nest (Ainley and Boekelheide 1990; McChesney et al. 1998; Carter et al. 2001). We set out 18

standing and 24 incubating cormorant decoys. The incubating decoys were placed on top of

synthetic nests made of rope and burlap, and held together with a natural fiber doormat (Figure

5). 

The remote video monitoring system, developed and installed on SPR by SeeMore Wildlife

Systems (Homer, Alaska) in 2003, was again utilized to enhance monitoring work. Two high

resolution video cameras were anchored to the rock near the top of the decoy area and connected

to a transmitter that sent live-streaming images to a portable, manually operated receiving system

on the adjacent mainland. The receiving system included a desktop computer equipped with

software for remote control of the cameras, with zoom and panning capabilities, squirt and wipe

for lens cleaning, and the ability to take still pictures and video. Between the two cameras, the

entire decoy area on SPR could be scanned at close range, with more limited viewing capabilities

of other portions of the southwest side of the rock. The video system enhanced our otherwise

poor viewing from mainland vantage points, which, prior to 2003, had been done solely with

spotting scopes from a distance of about one mile (1.6 km). Without the cameras, portions of the

decoy areas were not visible, and often poor visibility or heat waves precluded observations. 

During the late winter and early spring, in the months prior to the seabird breeding season, the

video system experienced a series of technical failures. In all, we visited SPR a total of three

times (6 March, 29 March, and 12 April) after the initial decoy deployment in efforts to repair

the video system and one malfunctioning sound system. The one sound system was never

repaired. On the video system, the remote motherboard and camera cables were replaced, and

Camera Two was returned to SeeMore Wildlife Systems for repairs, then reinstalled on 29

March. On the final trip on 12 April it was determined that the system was finally functioning

satisfactorily, although video recording was still not fully operable (but still functioning using

the “backcapture” feature). However, there were few subsequent difficulties throughout the

2004 field season. The video monitoring system was used successfully in addition to the

standard spotting scope monitoring of SPR. As with the scope, video scans were conducted

every 10 minutes during each SPR watch (see Seasonal Attendance Patterns, below). 
5

Monitoring Effort

Prior to the start of regular breeding season monitoring (16 April), DSR was monitored for 52.42

hours on 26 observation days between 12 November and 12 April 2004. After 15 April, DSR

and Devil’s Slide Mainland (DSM) were monitored for a total of 618.48 hours on 117

observation days between 15 April and 7 September. Prior to the start of regular breeding

season monitoring (before 17 April), SPR was monitored for a total of 44.32 hours, on 22 days

between 12 November and 12 April 2004. SPR was monitored for a total of 184.83 hours on 84

observation days between 17 April and 31 July. CRM/HPR was monitored for a total of 462.40

hours on 77 observation days between 8 April and 29 July (522.05 total person hours). 

Seasonal Attendance Patterns

Common Murre seasonal attendance patterns were examined at DSR, SPR, and at subcolonies

located at CRM, HPR, and BM227X using 65-130x Questar spotting scopes from standardized

mainland vantage points. Pre-breeding season (before 15 April) attendance was followed at

DSR only, with counts conducted once or twice a week and generally between 08:00 and 11:00

h, although times ranged from 07:10 to 14:15 h. During the breeding season, counts were

conducted at DSR every other day between 10:00 and 14:00 h. Breeding season attendance at

CRM, HPR, and BM227X was determined from counts conducted twice per week (weather

permitting), primarily between 08:00 and 12:00 h but times ranged 07:30 to 16:00 h. Each

colony, subcolony, or study plot was counted three times consecutively and the means reported. 

SPR was counted differently, as described below. Seasonal attendance data were collected at all

active subcolonies from mid-April (late pre-laying) until all chicks fledged and adult attendance

ceased for the season in monitored productivity plots.

Devil’s Slide Rock

Pre-breeding season attendance was monitored sporadically from 11 November 2003 to 2 April

2004. During the pre-breeding season when more than one count was made each day, the high

count was used to describe attendance patterns. “Breeding season” counts were conducted from

16 April to 11 August 2004. During this period, when more than one count was made between

10:00 and 14:00 h, the count closest to 10:00 h was used for better comparability. Counts were

conducted from a standardized observation site known as the Traditional DSR Pullout (see

Parker et al. 1997). In addition, an aerial survey was conducted on 3 March 2004 to examine

spatial distribution of murres on the rock prior to decoy deployment.

San Pedro Rock

From 9 December 2003 to 2 April 2004, SPR was monitored with spotting scopes only. From 17

April to 31 July 2004, the rock was monitored with a combination of video and scope work. 

During the latter period, attendance patterns were monitored during two-hour watches conducted

about every one to two days. To examine potential diurnal differences in attendance patterns,

watches were conducted on a rotating time schedule with more effort in the morning hours when

higher attendance would be expected: 06:20-08:20; 07:20-0920; 08:20-10:20; 12:20-14:20; and

14:20-16:20 h. Observations were made from the “Pipe Pullout” along Highway 1 (see Parker et

al. 1998), located about 1,700 m from the rock at an elevation of about 100 m. At the start of

each watch, the numbers of birds and marine mammals of each species present on SPR and in the

waters within about 300 m of the rock were recorded.

Watches were divided into ten-minute scans. When weather and viewing conditions allowed,

scans were conducted using both a Questar spotting scope and the remote video system. Data

were collected separately for both scope and video scans for comparison of each technique. 

When one observer conducted scans, the scope scan was conducted first followed by the video to

reduce bias of the better viewing video system. When two observers were present, one viewed
6

with the scope while another viewed simultaneously with the video. It should be noted that

while the video provided substantially better views of the decoy area, only scope scans provided

views of the entire south side of the rock. For this report, scope and video scans have been

combined to summarize murre and raven activity. Preliminary analyses indicate that video and

scope scans did not differ significantly in the number of birds detected. 

During each scan we recorded the number of murres and ravens seen on SPR, as well as their

behavior and location on the rock. Locations were recorded within one of five areas of the rock

(Figure 6). Murres attending SPR were reported in units as “murre-observations”, with each

murre seen during a scan constituting one murre observation. Information on raven attendance

was recorded in a similar manner, with each raven seen during a scan constituting one “raven

observation.” Ravens were monitored because the presence of these nest predators may reduce

murre attendance on the rock.

Castle/Hurricane Colony Complex

Seasonal attendance patterns of Common Murres were determined for 13 subcolonies at

BM227X, CRM, and HPR (ten nearshore rocks and three mainland areas; Figure 3). All visible

birds were counted at each subcolony from four standardized viewing locations. At three

subcolonies, separate subarea counts also were obtained as follows: 1) CRM-04, separate counts

were obtained for the productivity plot and “South Finger” (an ephemeral nesting area); 2)

CRM-06 South, counts were distinguished between areas 1 (South side) and 2 (North side; see

Knechtel et al. 2003); and 3) HPR-02, murre counts were distinguished between the traditional

“Ledge” and “Hump” subgroups.

Productivity - Common Murre

As in prior years, we monitored productivity of Common Murre breeding pairs at DSR and CRM

at least every two to three days (weather permitting) from mainland vantage points using 65-

130x Questar spotting scopes. All plots were monitored in a manner consistent with “Type I"

plots as described in Birkhead and Nettleship (1980). The locations of new, returning breeding,

territorial, and sporadic sites were identified using maps updated from the 2003 breeding season. 

At DSR, locations of murre sites were refined through the interpretation of aerial photographs

taken on 25 May 2004. We defined a “breeding site” as any site where an egg was laid and a

“territorial site” as a site that had attendance greater than or equal to 15% of monitored days. 

Sporadic sites were attended on at least two days but on less than 15% of days; however, many

possible “sporadic” sites were not identified as such because of the frequent movement by

visiting birds. New breeding, territorial, and sporadic sites established in 2004 were numbered

sequentially and added to existing maps created during previous years.

Although monitoring was conducted during all daylight hours, we conducted observations

predominantly in the morning when murre activity was greatest and lighting conditions were

best, which made site status easier to determine. Many observations also were conducted in

evening hours after mid-day heat waves dissipated. Each monitoring day, we determined the

status of each site, including the presence of adults, egg, or chick. Adult postures (i.e.,

incubating or brooding postures) and other behaviors (e.g., apparent egg turning, chick feeding)

also were used as indicators of site status, until presence or absence of an egg or chick could be

verified. From these data, egg laying date, hatching date, and chick fledging date (as well as egg

losses and egg replacements) were determined for each breeding site using a standardized

protocol. Chicks were considered to have fledged if they survived to at least 15 days of age. At

breeding sites where phenology was less certain, chicks were determined to have fledged based

on body size and plumage characteristics. From the data collected, we calculated the total

numbers of eggs laid, chicks hatched, and chicks fledged per pair, as well as hatching, fledging,

and breeding success.
7

Devil’s Slide Rock

We monitored murre productivity at all active and inactive (recorded since 1996) sites on DSR

with the use of 65-130x Questar spotting scopes. Using aerial photographs, we verified that all

sites could be seen from a combination of viewing locations along the mainland to the east and

southeast of DSR. Distances from observation locations to the rock ranged from 300 to 400 m.

On each observation day, all sites were monitored to determine the presence or absence of an

egg or chick. 

Castle/Hurricane Colony Complex

All active and inactive murre nesting sites were monitored within one productivity plot on CRM04 (established in 1996). An additional study plot on CRM-03 East, established in 1999, did not

host breeding murres in 2004. In 2004, the CRM-04 study plot consisted of 106 sites. 

Observations of the plot were conducted from or near the “Castle pullout” located off Highway

1, approximately 300 m from the CRM-04 plot. An additional viewing location from private

property above Funt Cove was added in 2003 and utilized again with permission in 2004. Both

Questar (65-130X) and Kowa (20-60X) spotting scopes were used for observations.

Adult Time Budgets - Common Murres

Time budget (or, co-attendance) observations were conducted at DSR in the latter part of the

season when approximately 50% of the breeding sites had chicks. Time budgets were conducted

only on breeding pairs with chicks, based on the assumption that co-attendance during chick

rearing is likely a better indicator of parental and feeding conditions than co-attendance during

incubation, since parents must feed themselves as well as their chick during this stage of the

breeding cycle. Criteria for selecting sites included:

1. Prior knowledge of the site as a nesting site;

2. Ease of viewing both adults (when both were attending the site at the same

time);

3. Proximity to other breeding sites; and

4. Ability to include additional nearby breeding sites;

The same breeding pairs were monitored during each observation period. Three continuous

watches were conducted between 1-9 July from sunrise to sunset (weather permitting) on 12-13

pairs of breeding murres.

Questar spotting scopes (65X-130X) were used to monitor arrivals, departures, and food

deliveries to chicks (including prey type and size). Observations were conducted by a primary

observer who was relieved every 2-3 hours. Information was recorded on a hand-held tape

recorder and later transcribed onto paper data forms and then transferred to a computer database. 

The information reported here includes the average time pairs of murres spent in co-attendance

per day at their breeding sites, as well as the average number of prey deliveries to the chick. For

the purposes of this report, co-attendance is defined as the period of time when two adults

(assumed mates based on behavioral interactions; see Johnsgard 1987, Gaston and Jones 1998)

were present together at a breeding site.

Disturbance

Disturbance events affecting murres at DSR and CRM/HPR were recorded incidentally while

collecting productivity and attendance data. Disturbances recorded included any event which

caused one or more of the following: adult murres to be flushed or otherwise displaced; any eggs

or chicks to be exposed, displaced, or depredated. Events which prevented prey from being
8

delivered to chicks were also considered to be disturbances. Data were then categorized as nonanthropogenic or anthropogenic disturbances.

Due to the close proximity of breeding Brandt’s Cormorants to murres at DSR and high

frequency of small-scale cormorant disturbances, we recorded displacement and flushing events

caused by cormorants only at murre breeding sites with an egg or chick present. In the case of

anthropogenic disturbances, aircraft flying at or below about 1,000 feet (305 m) above sea level

and boats within about 1,500 feet (460 m) of the nearest murre colony were recorded, even if

they did not cause disturbance. Information recorded regarding aircraft and boats included: type

of craft, any identifying number(s), direction of travel, and distance from the nearest subcolony

of murres.

To analyze disturbance events, we separated the data by source and type of disturbance. We

present the number of non-anthropogenic and anthropogenic disturbances seen per hour of

observation at each colony.

Brandt’s Cormorant Productivity and Nest Surveys

Productivity - Devil’s Slide Rock and Mainland

Since 1996, monitoring of Brandt’s Cormorant (hereafter, “cormorant”) productivity has been

monitored at DSR and the adjacent mainland. This monitoring is conducted to better understand

the influence of decoys on the DSR cormorant colony, the communal relationship between

breeding cormorants and Common Murres, and to examine differences in cormorant

reproductive performance between years and subcolonies. To determine timing of breeding and

productivity, breeding activities were monitored in detail at DSR and two subcolonies on DSM:

one on the south cliffs of the Devil’s Slide point (also known as “Mainland South”); and the

traditional Turtlehead Rock. Nests at all locations were monitored every three to seven days

from points along the mainland using a Questar (65-130x) or Kowa (20x) spotting scope. Chicks

were considered to have fledged if they survived to at least 25 days of age. After 25 days, many

chicks begin wandering from their nests, reducing the ability to determine which nests they

originated from (Carter and Hobson 1988; McChesney 1997). For each nest, we followed a

standardized protocol to determine the laying, hatching, and fledging dates, as well as clutch and

brood sizes and numbers of chicks fledged. We rated data quality for each parameter, and only

high-quality data were used for calculations. Means were then calculated for each parameter at

each subcolony.

Nest Surveys

In 2004, cormorant nest surveys were conducted at Devil’s Slide Rock and Mainland and

Castle/Hurricane subcolonies once per week during the breeding season. At Devil’s Slide,

counts were taken from the Traditional pullout along Highway 1 (see Parker et al. 1998) and

from the mainland bluffs above mainland subcolonies. Counts were taken between 08:00 and

11:00 h with a Questar spotting scope and 10x40 binoculars. At CRM/HPR, counts were taken

generally between 10:00 and 14:00 h from the Rocky Creek Bridge, Castle, and Hurricane

pullouts using a Questar spotting scope. For each count, cormorant territorial and nest sites were

classified into four groups to roughly describe breeding phenology: 1) little nesting material; 2)

poorly built nest; 3) fairly built nest; and 4) well-built nest. Numbers of large chicks also were

counted. At CRM/HPR, we report on the high count of well-built nests per subcolony and

associated dates. When possible we differentiated between juvenile, immature, and adult

cormorants, though age determinations were inconsistent because of distant viewing.
9

Aerial Photographic Surveys

In 2004, aerial photographic surveys were conducted at all murre colonies and most (greater than

about 10 nests) Brandt’s and Double-crested (P. auritus) Cormorant colonies in northern and

central California from the Oregon border south to Point Conception. These surveys are a

continuation of a long-term data set focused on monitoring seabird breeding populations in

California (e.g., Takekawa et al. 1990, Carter et al. 2001, Capitolo et al. 2004). Surveys were

conducted between 24 May and 2 June and were flown in a California Department of Fish and

Game twin-engine, high-wing Partenavia fixed-wing aircraft. Two personnel photographed

colonies through a hatch opening in the belly of the aircraft using 35 mm cameras. Overview

photographs of each colony were taken with a 50 mm or 70-200 mm zoom lens, while close-up

photographs used for counting were taken mostly with 300 mm lenses or occasionally with a 70-

200 mm zoom lens. Surveys of some areas were delayed by foggy conditions but were

completed later in the survey period. Most colonies were photographed on one day only. In

addition, a winter season survey was conducted on 3 March 2004 of nearshore murre colonies

between DSR and Point Reyes. This survey was conducted primarily to obtain photographic

documentation of murre spatial distribution on DSR prior to decoy deployment and to compare

winter attendance at the different murre colonies in the area. 

Counts at sample colonies were conducted using the “dotting” method and followed a

standardized protocol. Standardized count areas at the South Farallon Islands followed Capitolo

et al. (2002). As in other years since 1996, we obtained counts for all central California murre

colonies with additional counts of other Brandt’s Cormorant colonies in the Gulf of the

Farallones area. 

For murres, only birds were counted since they do not build nests. For cormorants, birds, nests,

and territorial sites were counted. Nests and territorial sites were categorized as follows: 1) wellbuilt nest with incubating/brooding adult; 2) nest with standing adult and visible chicks in the

nest bowl; 3) empty nest (i.e., no eggs or chicks) with standing adult present; 4) abandoned nest

(evidence of fairly to well-built nest with no adult present) ; 5) poorly built nest; 6) adult on

territorial site with little or no nesting material; and 7) undetermined site (either nest or territorial

site). We considered categories 1-5 as “nests” and categories 6 and 7 as territorial “sites”.

Colony Surveys - Other species

We conducted nest and bird surveys from boat and land at both the Devil’s Slide/San Pedro area

and Castle/Hurricane in 2004 to assess breeding populations of non-focal species, including:

Pelagic Cormorant (P. pelagicus); Western Gull (Larus occidentalis); Pigeon Guillemot

(Cepphus columba); and Black Oystercatcher (Haematopus bachmani). These species are not

covered in regular monitoring and many nesting areas cannot be seen from mainland vantage

points. On 18 June 2004, we conducted a boat survey between SPR and Pillar Point and counted

all potential nesting birds. The survey was conducted in the morning (07:00-10:50 h) when

larger numbers of Pigeon Guillemots, a crevice-nesting species, congregate on the land surface

and water at and adjacent to colonies. At Castle/Hurricane, nests and birds of all species were

counted from mainland vantage points on 9 June. A boat survey was attempted on 24 June but

only a partial survey was conducted due to rough sea conditions. For Pigeon Guillemots, we

present the high seasonal count obtained from colony counts and sea surface scans.
10

RESULTS

Social Attraction

Devil’s Slide Rock

Common Murre - In 2004, 241 active sites (190 breeding and 51 territorial) plus 11 sporadic

sites were recorded on DSR (Figure 7). This was an increase of 43 (21.7%) active and 80

(72.7%) breeding sites over the year 2003. Of the 190 breeding sites in 2004, 92 (48.4% ) were

reused breeding sites from 2003, 40 (21.1%) were territorial sites in 2003, six (3.2%) were not

used in 2003 but were used in previous years, and 46 (24.2%) were new sites in 2004. Ninetytwo active sites (38.2%) occurred within decoy areas (Figure 8).

San Pedro Rock

Common Murre - Murres were seen sporadically on SPR between 30 May and 31 July, but did

not establish territories or breed. Through a combination of Questar scope and remote video

scanning, murres were sighted on 14 of 84 (16.7%) observation days. Most murre sightings

were of single birds. Like past years, most activity occurred during the latter part of the breeding

season, particularly in late July. Most visiting murres attended a ledge below the main decoy

area that contained low densities of standing murre and cormorant decoys in a pattern resembling

a roosting area. This area is often used as a roost by pelicans, cormorants and gulls. 

The high count for SPR in 2004 was 11 murres on 28 July at 10:30 h. There were 104 total

murre observations, of which 87.5% were within decoy areas. Outside of decoy areas, there

were 10 murre observations on the “Nose Area” near the decoys, and three in the “Lower Area”

of the rock on the west end (Figure 6). Although two or more murres were occasionally seen

attending or flying on and off the rock together, no murres were seen billing, allopreening,

parading, or otherwise demonstrating courtship or other breeding behavior. 

Brandt’s Cormorant - Cormorants demonstrated no apparent response to the cormorant decoys

placed on SPR in 2004. Although cormorants often roosted in the lower “roost” portion of the

decoy area as well as other portions of the rock throughout the season, cormorants visited the

upper “breeding” decoy area primarily late in the breeding season (mid-July to early August),

where they roosted in small groups. There were no breeding-related behaviors observed.

Common Raven - Ravens demonstrated an intense interest in the mirror boxes once again in

2004. These mirrors had been turned around during the 2003 season to hide the reflective

surface, but were re-exposed in 2004 after removal of a nesting pair of ravens in 2003

(McChesney et al. 2004). However, ravens were seen interacting with their reflections quite

frequently in 2004, exhibiting both aggressive and inquisitive behaviors. After the mirrors were

turned around once again on 18 June, raven activity directed toward mirror boxes ceased,

although raven activity in other areas of SPR continued. Overall, raven activity was centered in

the Decoy Area and the adjacent Nose Area, with 82.4% of raven observations occurring in these

two areas. 

Seasonal Attendance Patterns

Devil’s Slide Rock

Common Murre - On DSR, murres were observed on 74 of 75 (98.7 %) colony count days

between 11 November 2003 and 11 August 2004 (Figure 9). Overall attendance this year was

high with 84% of counts exceeding 150 murres and 64% of counts exceeding the 2003 high

count of 214 murres. The 2004 high count was 336 murres on 28 April. However, this was

obtained at 07:30 h, outside the standardized seasonal attendance count period of 10:00-14:00 h,

so was not included in Figure 9. The highest standardized seasonal attendance count was 304
11

murres on 22 June. Attendance during the pre-breeding and early egg-laying period was highly

variable and then leveled out during the incubation period. Numbers increased during the chick

period, ranging 254-304 birds, but numbers began a steady decline in mid-July as chicks fledged

and adults departed the colony. 

A separate count of 285 murres (and 22 Brandt’s Cormorants) was obtained from aerial

photographs taken 3 March 2004 (Figure 15). These photographs showed the dense

concentrations that murres were attending on many days even prior to decoy deployment on 5

March. A comparison count of 242 murres made from the standardized mainland location

indicated that these colony counts are not entirely complete.

No murres were recorded on the Devil’s Slide Mainland in 2004. Small numbers were observed

among nesting cormorants in 2003 (McChesney et al. 2004).

San Pedro Rock

Common Murre - No murres were observed on 153 scans over 12 observation days during the

pre-season from 9 December 2003 to 2 April 2004. Of the 1,109 scans completed on SPR during

the field season (17 April - 31 July), 46 (4.1%) had at least one murre present, resulting in a total

of 104 “murre observations” (Figure 10). Thirty-one scans (67.4%) recorded one murre, three

scans (6.5%) recorded two, three scans (6.5%) recorded three, two scans (4.3%) recorded four,

three scans (6.5%) recorded five, one scan (2.2%) recorded six, two scans (4.3%) recorded nine,

and one scan (2.2%) recorded eleven murres. Murres were not seen on SPR until 30 May and

the last murre was observed on the final day of observations on 31 July. However, the murre on

30 May was oiled and likely was not associated with the social attraction system. Twelve of 14

days of murre sightings occurred during the last six weeks of the season, with five of the

fourteen occurring during the last ten days.

The video system allowed for an additional 254 scans not possible with the scope because of

poor visibility. These accounted for 22.4% of all scans conducted at SPR during the field

season. Thirteen scans had murre sightings, totaling 14 murre-observations, or 13.5% of total

murre-observations for the season.

Of 837 scans utilizing both video and scope, the scope detected murres on 10 scans when the

video system missed them, and on 13 scans the video system detected murres while the scope

missed them. Part of this discrepancy was likely because video and scope scans usually were not

conducted simultaneously (although occasionally two observers scanned simultaneously), and

birds may have arrived or departed in the brief moments between scan types. Overall, the video

system detected murres with slightly higher frequency (0.08 murres per scan) than the scope

method (0.07 murres per scan). This difference was not significant (paired t-test; t=-1.0,

P=0.33).

Common Raven - Ravens were observed on SPR throughout the winter, sometimes in groups of

5 or more. They were noted at least once on 13 of 18 (72.2%) observation days, with a high

count of 14 ravens on 2 April. During the breeding season, ravens were seen on SPR on 45 of 84

(53.6%) observation days, and were observed on 187 of the 1,109 (16.9%) scans completed, for

a total of 278 “raven observations” (Figure 10). Of the 278 raven observations, 115 (41.4%)

occurred in the Nose Area, 25 (9.0%) on the “West End”, 114 (41.0%) in the “Decoy Area”, 13

(4.7%) in the “Lower Area”, and the remaining 11 (4.0%) on the “East End” of the rock. Of the

187 scans in which ravens were seen, 102 (54.5%) recorded one raven, 83 (44.4%) recorded two

ravens, and two (1.1%) recorded five ravens.

Throughout our preseason observations we noted one pair of ravens in obvious association with

one another, and these two birds were frequently seen attending SPR with no other raven

present. They frequented the decoy area, especially around the mirrors. An active nest was
12

discovered on 17 April, on the south side of SPR high on the western-most peak. In an attempt

to discourage raven use of this area and learn more about the effects of ravens on the restoration

effort, one adult raven (probably the male of the pair) was collected , and the other member of

the pair shot but just injured, on 7 May. All collections were done under permit by a U.S.

Department of Agriculture wildlife biologist. The latter bird had been sitting in the nest earlier

in the day. Subsequent to this action, ravens were not observed for several days (Figure 10). 

However, about a week later, what was likely a new raven pair began frequenting the rock,

especially around the mirrors in the decoy area. Raven activity declined beginning in mid-June,

and on 18 June the mirrors were turned back around so their reflective sides were not visible. 

This may have helped further reduce raven attendance by decreasing attractiveness of the site.

Castle/Hurricane Colony Complex

Common Murre - Seasonal attendance patterns varied between subcolonies. Only four

subcolonies with confirmed breeding in 2004 were attended each count day from the start of

observations on 8 April until the start of egg-laying: CRM-04; CRM-07, BM227X-02 (Esselen

Rock), and HPR-02 (Figures 11-13). At CRM-02, CRM-03 West, and CRM-05 attendance was

especially sporadic until early May.

The subcolony on CRM-03 East did not attempt breeding in 2004. Murres attended sporadically

from the start of observations on 8 April until 11 May, at which point they stopped attending the

rock. Ravens were recorded flushing this subcolony six times on five observation days within

this period, and likely led to it’s abandonment. In 2003, ravens also caused several flushing

events at CRM-03 East and depredated at least three chicks (McChesney et al. 2004). 

During May (early to mid-incubation period), attendance was somewhat variable at most

subcolonies, followed by less variability in June during the late incubation and early chick

periods. Notable exceptions were at CRM-07, CRM-05 and both subcolonies at Hurricane Point

Rocks, which had more variable attendance throughout the breeding season.

Murre attendance again became sporadic after 24 June following a series of Brown Pelican

(Pelecanus occidentalis) disturbance incidents (see Disturbance, below). During the nine days

this single pelican was present, murres were flushed several times daily from the CRM

subcolonies and many birds spent considerable time rafting on the water nearby. Thus,

attendance counts after 24 June are not comparable to prior counts or past years. Counts

presented in Figures 11-12 after 24 June are the highest counts of up to several daily counts to

best represent the numbers of adults still attending the subcolonies, and are shown as dashed

lines. Ultimately these disturbances led to near or total breeding failure of all CRM subcolonies

and early colony departure by breeding adults in 2004. 

Productivity - Common Murre

Devils Slide Rock

Of 313 sites monitored at DSR in 2004, 190 (60.7%) were egg-laying, 51 (16.3%) were

territorial, 11 (3.5%) were sporadically attended, and 61 (19.5%) were sites (breeding, territorial,

or sporadic) in previous years that were unattended this season. Since they are difficult to follow,

the number of sporadic sites is likely underestimated.

The first murre egg observed on DSR in 2004 was an abandoned egg seen on 15 April. It is

unclear from which site this egg was laid, and this early egg may have been an infertile

“dumped” egg and is not included in summaries of phenology and breeding success. The next

egg was first observed on 27 April at a monitored site. Based on “first” eggs (n=190), mean egglaying date was 24 May (range = 27 April-3 July). “First” eggs include all sites where only one

egg was laid plus first eggs at sites where replacement clutches were laid. The first chick was

observed on 3 June. Mean hatching and fledging dates were 22 June (n=137) and 18 July
13

(n=128), respectively (Table 1). Chicks that fledged remained on the rock for an average of 24.9

days after hatching and the last chick was seen on DSR on 11 August. 

A total of 201 eggs were laid, including 11 replacement eggs. A total of 142 eggs hatched

(overall hatching success of 70.6%) and 133 chicks fledged (93.7% fledging success). The

number of chicks fledged per breeding pair was 0.70 (Table 1). Of 190 first eggs laid, 137

hatched (72.1% hatching success) and 128 chicks fledged (93.4% fledging success). Of 11

replacement eggs, 5 hatched (45.5% hatching success) and 5 chicks fledged (100% fledging

success).

Castle/Hurricane Colony Complex

Of 106 monitored sites in the CRM-04 plot in 2004, 85 (80.1%) were egg-laying and 21 (19.8%)

were territorial. There were four replacement eggs laid. 

At the CRM-04 productivity plot, the first egg was seen on 1 May and the first chick was

observed on 2 June. Based on first eggs only, the mean egg-laying date was 17 May (range= 30

April-11 June) and the mean hatch date was 18 June (range = 2 June-25 June). The last

replacement egg was laid on 15 June. Of the 89 eggs laid (including four replacement eggs), 54

(60.7%) hatched and one (1.9 %) chick fledged. The number of chicks fledged per breeding pair

was 0.01 (Table 1). It should be noted that the single chick considered to have fledged was

present on the rock for only 15 days, the minimum time required for fledging under our protocol. 

The 15-day mark was reached at the start of pelican disturbances, and it is unclear if the chick

actually fledged or died as a result of these events. The last chick was seen on 29 June, five days

after the start of pelican disturbance events. 

Although productivity was not monitored at other CRM/HPR subcolonies, other subcolonies

with confirmed breeding in 2004 were: BM227X-02 (Esselen Rock); CRM subcolonies 02, 05,

and 07; and HPR-02 (both Ledge and Hump). Breeding was not confirmed, though suspected,

on CRM-03 West and HPR-01. All but Esselen Rock are established subcolonies with annual

breeding in recent years. At Esselen Rock, breeding has occurred sporadically since 1996. As in

previous years, but not 2003, murres attended this rock in association with nesting Brandt’s

Cormorants. No cormorants, and no more than 2-3 pairs of murres, bred on Esselen Rock in

2003 (McChesney et al. 2004). Numbers of breeders also appeared to be small (possibly less

than 10-20 pairs) in 2004. At HPR-02 Ledge, 46 unattended chicks were counted during a

pelican disturbance event on 25 June when all but 15 adults were flushed from the area. This

was believed to represent most, if not all, murre chicks present on the Ledge subarea.

Adult Time Budgets - Common Murres

Devil’s Slide Rock

Coattendance of breeding sites by pairs of mated murres during chick-rearing was determined

from observations conducted between 1-9 July. Twelve to thirteen breeding sites were

monitored from dawn to dusk on three days, resulting in a total of 38 site-days monitored. Murre

pairs spent an average of 151.9 minutes per day in coattendance at their site (range 9-537

min/day; n=38). On average, mates arrived at their sites 5.4 times per day (range 1-12/day;

n=38). These mate arrivals resulted in prey deliveries 65.7% of the time. Chicks were fed on

average 3.4 times a day per site (range 0-8/day; n=38). Of 204 mate arrivals observed, 134 were

with prey, 53 were without prey, and 17 were unknown. Of 134 prey deliveries, 128 resulted in

chick-feeding, 4 resulted in an unknown prey fate, and 2 were eaten by the arriving adult. In

addition, one chick feeding was recorded when a prey item was stolen from a neighbor by a

coattending murre.
14

Disturbance

Disturbances are reported as either non-anthropogenic or anthropogenic. Disturbances per hour

were calculated based on total observation hours at each colony (see Monitoring Effort, above).

Non-anthropogenic Disturbance

During 2004, we incidentally observed 308 non-anthropogenic disturbances at the two

monitoring sites. Six disturbances were recorded at DSR, and 302 at CRM/HPR. 

Devil’s Slide Rock - There were six non-anthropogenic disturbance events observed at DSR. 

This resulted in an average of 0.010 disturbances per observation hour. All six of these

disturbances were caused by Brandt’s Cormorants and typically consisted of the cormorant

lunging and jabbing at the murre, causing the murre to become displaced from its incubating

position. Five disturbances were by cormorants nesting or attending a territory close to murre

sites, and four incidents resulted in egg loss.

Castle/Hurricane Colony Complex - Non-anthropogenic disturbances were difficult to record in

2004. This was due to the high frequency, high impact, and long duration of many events. In

many events of extended duration, birds were flushed and displaced repeatedly. In such cases,

the extended event was treated as one disturbance event, and an approximate total number of

birds affected was recorded.

There were 302 non-anthropogenic disturbance events recorded, resulting in 0.653 disturbance

events per observation hour (Table 2). Of these events, 293 (91.6%) caused murres to flush, two

(0.7%) caused murres to be displaced, and seven (2.3%) involved the loss of eggs or chicks. 

However, displacements are heavily underrepresented, since most flushing events also caused

birds to be displaced that were too difficult to follow. As a result of non-anthropogenic

disturbances, 45 egg and 28 chick depredations were observed.

 

Common Ravens were responsible for most non-anthropogenic disturbance events, contributing

to 184 (62.7%) flushing events, 37 (20.1%) egg depredations, and seven (3.8%) chick

depredations. Brown Pelicans were directly responsible for 97 (33.1%) flushing events and two

(2.0%) chick depredations. Indirectly, the pelican was responsible for at least six depredated

eggs and 21 depredated chicks; these egg and chick losses were due to raven and to a lesser

degree Western Gull predation (Table 3). However, many other eggs and chicks, likely

numbering in the hundreds, were lost when adults were forced to abandon their sites because of

repeated flushings by the pelican (see below for more details). Western Gulls caused four

(1.3%) flushing events and two (50.0%) egg depredations, Peregrine Falcons (Falco peregrinus)

caused two (0.6%) flushing events, a Turkey Vulture (Cathartes aura) contributed to one (0.3%)

flushing event, and 14 (4.7%) flushing events were due to unknown causes. Ravens flushed an

average of 89.5 murres per event and pelicans flushed an average of 111.3 murres per event. 

Western Gulls, Peregrine Falcons and Turkey Vultures flushed on average 35.5, 120 and 50

murres per event, respectively. 

On 25 April 2004, a raven nest was discovered low on a cliff face below Highway 1, about 100

m southwest of the “Castle Pullout” observation site. The nest faced west and was about 10 m

up the cliff from “Castle Cove” beach, approximately 300 m east of Subcolony CRM-04 (Figure

19). 

The first disturbance observed by a raven in 2004 occurred on 4 May, when approximately 150-

200 murres flushed from CRM-04. The first observed predation on a murre egg by a raven

occurred on 5 May. Subsequent to that event, a total of 35 murre egg predation events by ravens

were observed until the start of the pelican disturbance events on 24 June (see below). In
15

addition to the raven depredations, there were two observations of a Western Gull depredating

murre eggs as a result of those eggs being exposed during raven-caused flushing events. On one

additional occasion, an egg was dislodged during a raven flushing event and broken after

tumbling down the rock. In total, there were 38 lost murre eggs recorded due to raven

disturbance and predation prior to 24 June. Although both members of the raven pair were

responsible for disturbing murres, most predation was performed by the male. The pair members

were distinguished by plumage; the female, who performed incubation duties, had distinctive

white wing patches, while the male was all black.

On 24 May, a raven was observed for the first time aggressively approaching small nesting

groups of murres, causing the murres to retreat and expose their eggs. Up until this date, the

ravens were taking advantage of exposed eggs during flushing events caused by their overflights. On 26 May, both adult ravens were observed together for the first time on CRM-04; up

until this date only a single adult raven had been observed during disturbance events. It was also

on 26 May that a raven was first observed pulling a murre off it’s egg. The raven accomplished

these tasks by grabbing the murre’s wing-tip, or tail-tip, and pulling it back until it’s egg was

exposed. This predatory technique became more common as the season progressed. On 3 June,

a brood of four raven chicks was confirmed in the nest, all of which fledged by 18 June.

From 24 June to 2 July, an immature pelican was present at the CRM colony. During this period

the pelican flew frequently between CRM-02, CRM-03 West, CRM-04, and CRM-07, and

occasionally CRM-05. It landed on each rock repeatedly and appeared to deliberately approach

and flush groups of murres. The flushed murres would circle the rocks and either land on the

water nearby or return to the rocks in small groups, often only to be flushed again by the

pelican’s movements. Many murre chicks left unattended gathered in groups (or, “creches”),

with many hiding in small caves and crevices. The flushing events offered the opportunity for

the ravens, and to a lesser degree gulls, to depredate exposed murre eggs and chicks (Table 3). 

We believe the same immature pelican was responsible for these events at CRM based on its

continuous attendance at the colony, consistent behavior, and lack of other pelicans roosting

within the colony over that period (although flocks of migrating pelicans frequently passed by). 

An additional immature pelican was observed behaving similarly and flushing murres from

HPR-02 on 25 June. Murres observed flushing from HPR-02 during a boat survey on 24 June

likely resulted from this pelican as well. The two different pelicans were observed

simultaneously on 25 June, one at CRM and one at HPR-02. The HPR-02 pelican caused murres

to flush from both the Ledge and Hump, and at one point flushed all adult murres from the

Ledge, exposing all chicks which gathered into a creche. The impact of these flushing events on

HPR-02 subcolony are likely but unclear. HPR murres dispersed at roughly the same time as the

CRM murres, suggesting either breeding failure or somewhat early (compared to previous years)

and highly synchronous chick fledging.

A total of 86 flushing events were caused by the two immature pelicans during their stays. Other

pelican flushing events were caused by migrating flocks passing low over breeding murres. In

addition to egg and chick depredations, one murre chick was kicked by an adult murre during a

flushing event, and tumbled down the rock into the water. Between 24 June and 2 July we

observed six murre eggs and 21 murre chicks that were lost either directly or indirectly to pelican

disturbances.

Anthropogenic Disturbance

During 2004, we observed 11 aircraft disturbances and one boat disturbance at the two

monitored colonies. The disturbance rate at DSR was higher than at CRM/HPR. There were no

recorded disturbances at SPR.

Devil’s Slide Rock - A total of 147 aircraft and boats were incidentally observed near DSR: 66
16

(44.9%) were planes; 58 (39.5%) were helicopters; 20 (13.6%) were motorboats; and three

(2.0%) were kayaks. This resulted in an average of 0.238 motorcraft sightings per hour (Table

4). Eight of these motorcraft caused birds to be flushed from DSR, resulting in an average of

0.013 disturbances per hour. Seven of the eight disturbances were caused by helicopters (five of

which belonged to the U.S. Coast Guard) and one by a boat that came within 50 m of the rock. 

The greatest number of birds were disturbed on 22 May by a County Sheriff’s helicopter flying

at approximately 200 feet elevation that flushed about 50 birds, most of which were cormorants. 

Many of the planes were recorded on 25 April during the “Dream Machines” auto and air show

at Half Moon Bay Airport. During the course of that day, 27 low overflights were recorded and

no birds were observed flushing. However, by 10:30 h there were fewer than 50 murres on DSR

and none remained by 13:30 h. It is believed that unusually warm air temperature on 25 April

caused the colony to disperse to sea early in the day. On 26 June, 67 motorcycles heading south

on Hwy 1 caused a large percentage of the murre colony to head-bob.

Castle/Hurricane Colony Complex - Only four anthropogenic disturbances resulted in birds

flushing at CRM/HPR, an average of 0.008 disturbances per hour. All of these occurred during

the Big Sur Marathon on 25 April and were the result of a single California Highway Patrol

helicopter circling over the area. The helicopter was flying at approximately 1500 ft. during

each pass and apparently caused birds to flush from CRM-03 East (5 murres), CRM-03 West (40

murres) and twice from CRM-04 (40 and 5 murres, respectively). However, prior to the

overflights, murres had been flushing from the rocks for unknown reasons, which may have

partly explained their flushing due to an aircraft at fairly high altitude. 

Brandt’s Cormorant Productivity and Nest Surveys

Productivity - Devil’s Slide Rock and Mainland

In 2004, Brandt’s Cormorants bred on DSR, the west and southwest side of the DSM

promontory (“Mainland South;” MS), and on Turtlehead Rock (TRTH; Figure 2). All clearly

visible egg-laying sites on DSR and TRTH were monitored, as well as a large, contiguous

sample of nests on MS. Total numbers of breeding sites followed in all locations were 91

(DSR), 61 (MS), and 24 (TRTH).

On DSR, mean clutch initiation date for first clutches was 12 May (n=82 nests), with a range

from 15 April to 26 June. On average, 3.3 (n=63 nests) eggs were laid per first clutch (Table 5). 

The mean hatching date was 10 June (n=74), with a range from 23 May to 17 July. Chicks

hatched at 89.0% of breeding sites (including one successful replacement clutch), and fledged at

83.5% of breeding sites. For first clutches only, an average of 2.3 (n=90) chicks hatched per

breeding pair, and hatching success of all eggs on DSR was 63.2% (n=62). Excluding the

replacement clutch, an average of 1.9 (n=90) chicks fledged per breeding pair, and fledging

success of all chicks was 85.3% (n=90). Breeding success (number of chicks fledged per egg

laid) was 53.4% (n=62). One replacement clutch of four eggs was observed on DSR. This effort

hatched two chicks that were both raised to fledging age.

On MS, mean clutch initiation date was 4 May (n=57), and ranged from 10 April to 29 May

(Table 5). On average, 3.4 eggs were laid per clutch (n=59). The mean hatching date was 5

June (n=56), and ranged from 14 May to 28 June. Chicks hatched at 96.7% of breeding sites, and

fledged at 95.1% of breeding sites. Hatching success was 80.6% (n=57), fledging success was

90.1% (n=59), and breeding success was 72.4% (n=57). On average, 2.7 chicks hatched (n=59)

and 2.4 chicks fledged (n=61) per breeding pair. No replacement clutches were observed.

 On TRTH, mean clutch initiation date was 6 May (n=24) and ranged from 12 April to 21 May

(Table 5). On average, 3.7 eggs were laid per clutch (n=23). The mean hatching date was 7

June (n=24), and ranged from 27 May to 21 June. Chicks hatched and fledged at all breeding

sites. Hatching success was 78.6% (n=23), fledging success was 79.7% (n=24), and breeding
17

success was 61.9% (n=23). On average, 2.9 chicks hatched (n=24) and 2.3 chicks fledged

(n=24) per breeding pair. There were no replacement clutches.

Nest Surveys - Devil’s Slide Rock and Mainland

Poorly-built and well-built cormorant nests were counted weekly on Devil’s Slide Rock and all

mainland subcolonies beginning on 17 April 2004 (Table 6). Numbers of poorly-built nests were

highest in mid-April and began to decline as nests were completed at the onset of egg-laying in

early May. On 22 June and 30 June, approximately two weeks after the mean hatching date for

all DSR subcolonies, peak counts of well-built nests were recorded. After this time, counts of

well-built nests declined as chicks began to wander from nests and nests were destroyed.

Nest Surveys - Castle/Hurricane Colony Complex

Well-built cormorant nests were observed at the following subcolonies: BM227X-02 (Esselen

Rock), CRM-06 South, CRM-07,CRM-09, and HPR-02 (Table 7). Egg laying likely began in

late April, when the first well-built nests were observed, and probably continued into June. 

Numbers declined on CRM-07 after the start of the pelican disturbances on June 24, possibly

indicating low breeding success on this rock, although pelican disturbances were not observed to

have affected cormorants.

Aerial Photographic Surveys

Aerial photographic survey data on Common Murres, Brandt’s Cormorants, and Double-crested

Cormorants at sample central California colonies are reported by colony in Table 8 and by

subcolony in Appendix 1.

Compared to 2003 (McChesney et al. 2004), murre counts increased at most colonies. Changes

in bird numbers at individual colonies ranged from -20.6% at CRM to +57.6% at Double Point

Rocks, with an average change of +25.1%. The aerial survey count of 291 murres on DSR was

51.6-102.1% higher than the two aerial counts in 2003, or 73.2% higher than the average of the

two 2003 counts. This is consistent with the 72.7% increase in breeding pairs on DSR in 2004. 

Numbers also increased substantially at Miller’s Point Rocks (+47.0%), contributing to a 40.2%

increase for the Drake’s Bay Colony Complex (including Point Resistance, Miller’s Point Rocks,

and Double Point Rocks). The only colony showing substantial decline was CRM, but increases

at BM227X and HPR resulted in an overall increase of 4.5% for the Castle/Hurricane Colony

Complex. Counts at the two largest central California murre colonies, North and South Farallon

Islands, were essentially unchanged (-0.7% each) for the second straight year. Numbers of

murres at all colonies combined were 4.2% higher than in 2003, driven by a 21.1% increase at

the nearshore colonies.

Numbers of Brandt’s Cormorant nests increased at most colonies compared to 2003 (Capitolo et

al. 2004, McChesney et al. 2004). Changes at individual colonies ranged from -48.7% (CRM) to

+410% (Miller’s Point Rocks). Numbers increased within all colony complexes except North

Farallon Islands (-48.0%), ranging from +20.2% at Lobos/Seal Rocks to 81.1% at Drake’s Bay. 

The largest Brandt’s Cormorant colony, South Farallon Islands, increased 25.1%. Devil’s Slide

increased 31.6% and Castle/Hurricane increased 28.2%. At all sample colonies combined, nest

numbers increased 30.7%. However, this total does not include all Brandt’s Cormorant colonies

in the region, as several large colonies occur between Año Nuevo and Castle Rocks. Inclusion

of all colonies will be needed to further assess overall population changes for this species in

2004.

Count data indicated the timing of surveys coincided well with Brandt’s Cormorant breeding

phenology. For example, poorly-built nests (i.e, nests in early stages of construction) accounted

for less than 5% of nests at most colonies, and numbers of territoral sites were also low. 
18

Phenology was earlier at Alcatraz Island, where 16% of nests had visible chicks. No other

colonies had visible chicks in nests in 2004.

We only counted one Double-crested Cormorant colony in the region, the South Farallon

Islands. This is the only offshore colony in our focal area between Point Reyes and Hurricane

Point, although several other colonies occur in the San Francisco Bay area. Our nest count at the

South Farallones was 27.8% higher than in 2003.

Colony Surveys - Other Species

Results of colony surveys for Pelagic Cormorants, Western Gulls, Pigeon Guillemots, and Black

Oystercatchers at Devil’s Slide/San Pedro and Castle/Hurricane are summarized in Tables 9 and

10. Figure 14 shows the corresponding count areas between San Pedro Rock and Devil’s Slide. 

At CRM, the high count for Pigeon Guillemots occurred at the fairly late date of 1 July, when 13

birds were counted on the water. Most sightings of guillemots at CRM occurred on or just

offshore of CRM-04, CRM-05, and CRM-07. Counts at Castle/Hurricane are not considered

complete since only a partial boat survey was conducted. 

DISCUSSION

The 2004 breeding season marked the ninth consecutive year of seabird restoration and

monitoring efforts in central California by the Common Murre Restoration Project. Efforts have

focused on reestablishing breeding and increasing colony size at the recently extirpated murre

colony at DSR, reestablshing breeding at the long-extirpated SPR colony, assessing the status of

other nearshore murre colonies, and identifying other methods to restore the nearshore portion of

the central California murre population. 

A major project goal was to obtain 100 breeding pairs of murres on DSR within 10 years, using

social attraction techniques. The 2004 breeding season marked the fourth consecutive year this

goal was reached and surpassed. The 190 breeding pairs was an increase of 73% over 2003 and

54% higher than the previous high of 123 pairs in 2002. The increase in breeding pairs was

complimented by an increase in overall attendance throughout both the pre-breeding and

breeding seasons. Most counts ranged from about 200 to 260 murres, and the 2004 high count of

336 birds was 57% higher than our previous recent high of 214 birds in 2003. High attendance

and an increase in new breeding sites indicated a high level of recruitment to DSR in 2004 which

can be expected to continue in future years. While recruitment likely resulted in part from birds

hatched at other colonies, it likely included birds hatched at DSR since 1996, with most of these

hatched since the first larger cohorts began in 1999. Murres begin breeding at about age 3-9

years (summarized in Ainley et al. 2002).

Murre breeding success on DSR (0.70 chicks per pair) was 9.4% higher than in 2003, when

breeding efforts were hampered by mild El Niño conditions, disturbance by roosting pelicans

and cormorants, and possibly aircraft disturbance (McChesney et al. 2004). Average lay dates

were also about eight days earlier in 2004 than in 2003. However, breeding success in 2004 was

below average and was the second lowest since 1999. Most nest failure occurred during the egg

stage. Co-attendance (time budget) watches showed much higher average levels of co-attendance

than 2003 (151 min in 2004 compared to 63 min in 2003), but average number of mate arrivals

was similar and average number of chick feeds/day was actually less (3.5 in 2004 compared to

4.5 in 2003). Lower breeding success and reduced chick feeding may reflect recruitment of

relatively large numbers of first-time breeders which do not reproduce as well as more

experienced adults. 

Social attraction efforts at DSR in 2004 were little changed from 2003. Decoy numbers were
19

reduced somewhat (17.6%) but were placed in roughly the same configuration. The reduction in

decoys appeared to have little to no effect on the murre colony. Most breeding sites were

returning sites, indicating a high level of return by previous breeders. Given the size of the

colony in 2004, in some areas decoys actually appeared to displace murres. Examination of

murre attendance patterns before and after decoy deployment in early 2004 showed high

attendance before deployment and suggested that on certain parts of the rock murres occurred in

higher densities before decoy deployment. After decoy deployment, certain decoys took up

space previously occupied by live murres. 

Most new sites in 2004 were within or on the edge of previously existing breeding groups. “The

Bridge” area between plots 9 and 10 experienced a substantial extension upslope into an area

used as a non-breeding “club” in 2003. Another “bridge” was formed between breeding groups

in plots 2 and 4 by the addition of several new breeding sites in the Plot 3 area. Murres also

established new sites in formerly unused portions of DSR. For example, four breeding and three

territorial sites were in a new area on the far southwest end of the rock, and three breeding and

nine territorial sites were in two disjunct areas on the far northeastern portion of the rock. We

view these as positive steps toward the permanent reestablishment of a self-sustaining murre

colony on DSR which occupies most available breeding habitat and attains a population size in

the thousands, as existed in the past.

This was the seventh consecutive year of social attraction efforts at SPR. Efforts to increase the

attractiveness of SPR for murres were expanded in 2004, with the re-deployment of cormorant

decoys (as in 2003), manipulation of mirrors, and removal of a breeding pair of ravens. 

However, results in 2004 were similar to most other years, with no pre-breeding season

attendance, little breeding season attendance, most activity occurred in late July when chicks

were fledging at other nearby colonies, most visits were to the lower portion of the rock

frequented by other roosting birds, and no breeding by murres. Cormorants also did not show

interest in the cormorant decoys, which were placed in hopes of attracting nesting cormorants

that may have enhanced attraction of murres to the rock. While continued efforts over more

years might eventually have led to recolonization of SPR by murres, after much thought and

discussion we decided to discontinue these efforts following the 2004 season. Dwindling project

funds and timeline plus a high level of difficulty installing and maintaining equipment on SPR

guided this decision. However,valuable knowledge was gained from this effort that will benefit

our assessment of restoration efforts at DSR and future efforts.

With almost if not total reproductive failure, breeding success at the Castle Rocks and Mainland

murre colony in 2004 was by far the worst since we began monitoring in 1996. The presence of

a breeding pair of ravens that fledged four chicks on the CRM mainland cliffs had a large impact

on the colony. The murre subcolony at CRM-03 East, which contained one of two productivity

plots, was abandoned prior to egglaying following several disturbance events by ravens. 

Frequent disturbance during the pre- and early egg-laying period on other subcolonies, especially

CRM-04, likely led to delayed breeding and nest abandonment at some sites. The high predation

rate on murre eggs and chicks also contributed to low breeding success. However, even worse

than raven impacts was the extended visit by a single juvenile Brown Pelican that actively

chased and flushed murres from breeding sites near continuously for the better portion of nine

days. Pelican impacts included losses of large numbers of eggs and chicks that were displaced

and abandoned or exposed and scavenged by ravens and gulls. Similar disturbance on HPR-02

by another juvenile pelican on one to two days in late June likely led to losses there as well, but

to what degree is unknown. Curiously, seasonal murre attendance at both HPR subcolonies

ceased earlier than average and almost simultaneously along with the failed CRM subcolonies

(except for a brief resurgence at HPR-02), suggesting failed breeding at HPR as well.

Efforts to reduce anthropogenic disturbance were continued in 2004 with additional outreach,

including: 1) in April 2004, an informational letter on the effects of aircraft disturbance on

seabirds, methods to avoid disturbance, and maps of sensitive colonies was mailed to 123
20

airports, aviation companies, and flying clubs throughout the San Francisco Bay area; 2) on 28

April, we coordinated with the Monterey Bay National Marine Sanctuary on a 45-minute

presentation of similar information that was given to the pilots of the Coast Guard Group San

Francisco during one of their safety briefings; 3) on 25 April at the 2004 Dream Machines Car

and Air Show at Half Moon Bay Airport, we handed out flyers on effects of human disturbance

to seabirds and coordinated with event organizers and air tour operators to reduce overflights

near DSR during the show; and 4) on 25 April, we continued coordinating with organizers of the

Big Sur Marathon and monitoring for disturbance during that event. These efforts appear to be

having substantial benefits, as aircraft overflights and disturbance during the Dream Machines

and Big Sur Marathon, as well as the remainder of the year, were highly reduced in 2004. 

Efforts for reducing disturbance to seabirds were enhanced by the conviction in November 2004

of a helicopter pilot (J. Cheatham of Verticare, Inc.) for disturbing murres at CRM, a violation of

the federal Airborne Hunting Act (“Act”; 50 CFR 27.51). This disturbance was recorded during

the Big Sur Marathon (“Marathon”) on 27 April 2003. During that event, the pilot’s helicopter

flew low (<1,000 feet) over CRM several times, flushing birds on three passes according to

project observers. Aircraft similar to the defendant’s had been recorded flushing murres off

CRM during past Marathons, which Verticare filmed each year, dating back at least to 1999

(USFWS, unpubl. data). Many contacts had been made with Cheatham and other pilots to advise

them of the need to prevent disturbance of birds and the associated laws. Following recorded

disturbance from this pilot’s aircraft in the 2002 Marathon, USFWS law enforcement mailed the

pilot a warning letter informing him of the law regulating harassment of wildlife by aircraft. In

2003, disturbances were documented by project personnel and the information passed on to

USFWS law enforcement and the U.S. Attorney Office. Three citations were issued by USFWS

law enforcement charging three separate violations of the Act. The defendant pled not guilty and

a federal jury trial was conducted 16-19 November 2004 in San Jose, California. The defendant

was found guilty of one count of “harassing” murres with his aircraft. This conviction, along

with other outreach, may have substantial benefits to murres and other seabirds by demonstrating

the will of federal agencies to enforce environmental laws that have been transgressed by aircraft

and emphasizing the personal responsibility pilots have to avoid wildlife impacts.
21

ENVIRONMENTAL EDUCATION PROGRAM

OVERVIEW

The environmental education component of the Common Murre Restoration Project, conducted for

2.5 months in the fall, continued for the ninth year. This program serves two main functions: 1) to

provide environmental education, especially on seabirds, to local children; and 2) to provide

assistance to the project in maintaining murre decoys for the next year’s deployment. These

objectives are accomplished through classroom instruction and activities, including murre decoy

painting.

In 2004, 33 classes ranging from kindergarten to 5th grade participated in the program.

Approximately 6,250 students from the San Francisco Bay Area (Montara, Pacifica, Half Moon

Bay, El Granada, Fremont, San Jose, and San Leandro) have participated since the program’s

inception. As in past years, the education project focused on: 1) natural history, ecology, biology

and physiology related to seabirds, especially Common Murres; 2) the 1986 Apex Houston oil

spill and its impact on the Common Murre colony on DSR; 3) current and historical pressures

affecting seabird decline; and 4) the social attraction restoration efforts at DSR and SPR. The

education program was divided into two separate presentations given about four weeks apart.

The first presentation consisted of a participatory activity exploring seabird adaptations and a

slide show summary of the project. The second presentation was conducted after decoys were

cleaned and prepared for painting. This presentation included a review of seabird adaptations, an

activity emphasizing the importance of coloring for camouflage, painting the decoys, and a

group activity building a Common Murre food pyramid. All presentations were given between

14 September 14 and 3 November.

PARTICIPANTS

In 2004, nine schools from four school districts with 32 teachers and approximately 880 students

participated in the education program. There were no new schools participating this year. However,

Sunset Ridge rejoined the program after taking a year off. There were also nine new teachers

participating. 

Cabrillo Unified School District

El Granda Elementary

Jennifer Austin, 3rd grade, 22 students

Sue Hatfield, 3rd grade, 22 students

Pauline Shue, 3rd grade, 22 students

Lisa Steinburg, 3rd grade, 22 students

Farallone View Elementary

Linda Carroll, K/1st grade, 20 students

Laura Cooke, K/1st grade, 20 students

Rebecca Johnson, 2nd/3rd grade, 20 students

Diana Purucker, 2nd/3rd grade, 20 students

Hatch Elementary

Maria De La Cueva, 4th grade-immersion, 32 students

Lyn Kelly, 5th grade, 32 students

Bruce Linton, 5th grade-immersion, 32 students

Ann Mangold, 4th grade, 32 students

Vicki Reno, 4th/5th grade, 32 students
22

Pacifica Union School District

Cabrillo Elementary School

Tiffany Leung, 4th grade, 32 students

Dwan Padilla, 4th grade, 32 students

Ocean Shore Elementary

Sheila Gamble, 3rd grade, 32 students

Jonathon Harris, 4th/5th grade, 40 students

Sunset Ridge Elementary

Pat Costa, 3rd grade, 18 students

Chris Elvander, 3rd grade, 18 students

Vallemar Elementary

Doreen Barnes, 5th grade, 32 students

Cheryl Bingham, 3rd grade, 20 students

Anne Haas, 1st grade, 20 students

Jean McMartin, 5th grade, 32 students

Elizabeth Myers, 3rd grade, 20 students

Katie Pardee, 1st grade, 20 students

Tami Taylor, 3rd grade, 20 students

Alyce Wassall, 1st grade, 20 students

Union School District

Oster School

Barbara Finkle, 4th grade, 28 students

Beth Miller, 4th grade, 28 students

Dawn Ullmark, 4th grade, 28 students

Fremont Unified School District

Warwick Elementary

Melanie Moreno, 4th grade, 96 students (3 classes)

Ann Trammel, 4th grade, 32 students

TEACHER RESOURCE MATERIALS

Participating teachers were provided with the following educational materials:

Returning Home: Bringing the Common Murre Back to Devil’s Slide Rock. (The

Common Murre Restoration Project 1999) VIDEO. 24 min.

Trashing the Oceans. (NOAA 1988) VIDEO. 7 m in 21 sec.

Learn About Seabirds Curriculum Guide with supplements. (USFWS 19995b)

Poster: Threats to CA Coastal and Marine Life. California Coastal Commission.

Zoobooks: Seabirds. (Burst 1995)

A Guide to Alaska Seabirds. (Alaska Natural History Society 1995)

Learn About Seabirds. (USFWS 1995b). SLIDESHOW (30 slides)

Seabirds. (Rauzon 1996)

Project Puffin: How We Brought Puffins Back to Egg Rock. (Kress and Salmansohn

1997)

Giving Back to the Earth: A Teacher’s Guide for Project Puffin and Other Seabird

Studies. (Salmansohn and Kress 1997)

Educator Workshops/Field Trip Sites Resource Information

Each school’s library has received one copy of:
23

Project Puffin: How We Brought Puffins Back to Egg Rock. (Kress and Salmansohn

1997)

Seabirds. (Rauzon 1996)

DECOY CLEANING AND REPAIR

The process of cleaning decoys included soaking each decoy in water for about 24 hours,

scrubbing them with a wire brush to remove excess guano, and rinsing with clean water. The

power washer was not used this year as rinsing with a regular hose attachment provided

sufficient rinsing. Murre Project staff and volunteers spent about 200 person hours cleaning

decoys in 2004.

During and following the decoy painting period, repairs were made to decoys in need.

Approximately 100 wooden decoys needed head reattachment and/or bill repair. A wooden

dowel was used in reattaching heads to provide extra support. Wood filler was used to fill in any

cracks after reattachment. A wooden dowel was also used for decoys that had half or more of

the bill missing. A dowel was inserted to determine the correct bill length and wood filler was

formed around the dowel to create the shape of the bill. An electric sander was used to smooth

out both head and bill repairs. 

 

CLASSROOM PRESENTATIONS

Initial Visits

Adaptations Activity

After a short introduction to the Project, the majority of the presentation consisted of the “Build

a Bird” activity modified from the Learn About Seabirds binder. This was a highly participatory

activity in which all of the students were actively engaged. Whenever possible, questions were

used in the presentation to encourage creative thinking and problem solving during the activity. 

A student was randomly selected to be turned first into a bird, and then a seabird, and then

finally a Common Murre. This transition was accomplished by attaching representative objects

to the student for each adaptation. Twelve students read aloud cards of bird/seabird adaptations

or seabird threats as needed, while the rest connected the adaptation/threat to the object on their

desk and pinned it to the ‘bird.’ For example, the “Down Feathers” card printed with the

statement of function was read aloud and discussed; the down jacket was identified as a

representative object for the adaptation; and finally the jacket was placed on the ‘bird.’ Other

represented adaptations included contour feathers, hollow bones, air sacs, bill/beak, webbed feet,

oil gland, and salt gland; wings, guano and murre eggs were also discussed without an

accompanying card. The guano discussion included examining the ocean food web and the flow

of nutrients. Once transformed into a Common Murre, four threats to seabirds were discussed in

a similar format: disturbance; exotic and native predators; plastic trash; and oil pollution. The

students brainstormed ways to prevent and mediate these threats.

Slide Show

A slide show comprised the final 15 minutes of the presentations. This slide show gave an

overview of the Common Murre Restoration Project including: the natural history of the

Common Murre; the effects of the 1986 Apex Houston oil spill on the colony at DSR; and the

restoration efforts on DSR and SPR. The annual activities were explained in chronological order,

starting with the deployment of the decoys and concluding with the students’ role in preparing

decoys for deployment. Approximately 10 or more minutes were devoted to questions and

answers after the presentation.
24

Assistants

Both a Murre Project staff member and the Environmental Education Specialist from the

Refuge’s Visitors Center attended an initial visit for observation and assistance. Assistance was

provided for about half of the painting presentations by a Refuge employee, volunteer, or SCA

intern.

Final Visits (Painting Decoys)

This presentation began with a review of the adaptations of the Common Murre. Students

recalled both the adaptation and its function. Next the students participated in a feeding-relayrace activity to reinforce the adaptive function of the camouflage in predation. The students were

separated into four teams. Each team had an assigned ‘feeding ground’ consisting of a white or

black poster board covered with equal numbers of black and white fish-shaped pieces. The teams

‘fed’ simultaneously for a set amount of time and then the results were analyzed in relation to

coloration. The students then painted the decoys. Many of the schools attended had two or four

classes participating. The first class would paint the white part of the decoy while the second

class would paint the black. This allowed time for the white paint to dry before the black was

painted to prevent the two colors from mixing. After the decoys were painted, the class created a

Common Murre food web together. Phytoplankton, zooplankton, squid, rockfish, sardines, and

the Common Murre were attached to a poster with Velcro when students correctly guessed

where they belonged on the pyramid. The importance of bringing the murre back to Devil’s

Slide Rock was discussed after the pyramid was fully constructed. The presentation concluded

with a question and answer period.

CLASSROOM EXTENSION ACTIVITIES

Teachers and students have used the curriculum materials to conduct a number of activities and

projects, varying from making paper mache eggs to writing stories. Participant classes received

monthly newsletters during the spring with updates of the number of Common Murres, eggs, and

chicks on DSR and SPR. As the breeding season progressed students tracked the number of

Common Murres attending DSR and SPR by using a data chart in their classroom.

EDUCATION PROGRAM SUMMARY

The ninth year of the Common Murre Restoration Project’s Environmental Education Program

served many students by providing active participation in a local natural resource restoration

project. Students continued to assist the project by repainting murre decoys while gaining

knowledge of seabirds and marine conservation. Participants demonstrated a strong interest in

Common Murres and their restoration, and retained much of the presented information from this

year and past years. Many students, parents, teachers, and school staff living near the sites

mentioned watching for the birds, decoys and biologists when they drive by the Devil’s Slide

area of Highway 1. The teachers who have participated for several years highly praised the

project as an essential part of their curriculum. This year’s education program was highly

successful, reaching approximately 880 students and welcoming 9 new teachers. However, due

to a reduction in the number of decoys deployed, the education program will no longer be able to

offer decoy painting to the schools. Therefore, it will be necessary to design a new curriculum if

the Education Program is to continue in future years. Participating teachers received a letter

regarding this change and were asked for input for a potential new curriculum. 
25

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Storm-Petrel. Unpubl. Ph.D. dissertation, University of Michigan, Ann Arbor, Michigan.

Podolsky, R.H., and S.W. Kress. 1989. Factors affecting colony formation in Leach's StormPetrel. Auk 106:332-336.

Podolsky, R.H., and S.W. Kress. 1991. Attraction of the endangered Dark-rumped Petrel to

recorded vocalizations in the Galapagos Islands. Condor 94:448-453.

Rauzon, M.J. 1996. Seabirds. Franklin Watts/Grolier Publishing, New York, New York.

Ray, M.S. 1909. The passing of the Pedro Island seabird rookery. Condor 11:94-96.

Roletto, J., J. Mortenson, I. Harrald, J. Hall, and L. Grella. 2003. Beached bird surveys and 

chronic oil pollution in central California. Marine Ornithology 31:21-28.

Salmansohn, P., and S.W. Kress. 1997. Giving back to the earth: a teacher’s guide for Project

Puffin and other seabird studies. National Audubon Society. Tilbury House, publishers,

Gardner, Maine.

Schubel, S.E. 1993. A Common Murre attraction project on a Maine island. Unpublished report,

National Audubon Society, Ithaca, New York.

Siskin, B.R., G.W. Page, and H.R. Carter. 1993. Impacts of the 1986 Apex Houston oil spill on

marine birds in central California. Unpubl. report, U.S. Dept. of Justice, Washington,

D.C.

Sowls, A.L., A.R. Degange, J.W. Nelson, and G.S. Lester. 1980. Catalog of California

seabird colonies. U.S. Department of Interior, Fish and Wildl. Serv., Biol. Serv. Prog.

FWS/OBS 37/80.
29

Swartzman, G. 1996. Resource modeling moves into the courtroom. Ecological Modeling

92:277-288.

Sydeman, W.J., H.R. Carter, J.E. Takekawa, and N. Nur. 1997. Common Murre Uria aalge

population trends at the South Farallon Islands, California, 1985-1995. Unpublished

report, Point Reyes Bird Observatory, Stinson Beach, California; U.S. Geological

Survey, Dixon, California; and U.S. Fish and Wildlife Service, Newark, California.

Takekawa, J.E., H.R. Carter, and T.E. Harvey. 1990. Decline of the Common Murre in Central

California 1980-1986. Studies in Avian Biology 14:149-163.

U.S. Fish and Wildlife Service. 1995a. Notice of availability, final Apex Houston oil spill

restoration plan. Federal Register 60(81):20739-20749.

U.S. Fish and Wildlife Service. 1995b. Learn About Seabirds: A Curriculum Teacher’s Guide.

Second Printing.
30

Figure 1. Map showing the location of the two study sites along the central California coast. Devil’s Slide Rock an

shown) are located within the Devil’s Slide Colony Complex.
31

 

Figure 2. Devil’s Slide Colony Complex including colonies and subcolonies monitored by

the Common Murre Restoration Project.
32

Figure 3. Castle/Hurricane Colony Complex, including Bench Mark-227X (BM227X), Castle

Rocks and Mainland (CRM), and Hurricane Point Rocks (Hurricane). Labels indicate

subcolonies mentioned in the text.
33

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2 0 2 4 

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S

Speaker2x4 

h

MirrorSolar panel 

%U Territorial Sites 

%U Breeding Sites 

ÚÊ Dowel

Decoys 

Figure 4. GIS map of Devil’s Slide Rock, 2004. Common Murre breeding and territorial sites are shown in relatequipment.
34

Figure 5. Photograph of Common Murre and Brandt’s Cormorant decoys on San Pedro Rock.
35

Figure 6. San Pedro Rock (south side) as it appears from the viewing location along Highway 1. The rock is divfor recording bird and marine mammal locations (West End, East End, Lower, The Nose, Decoy Area).
36

6

5

9

9

1310

7016

9825

113

45

123

43

110

88

0

50

100150200250

No. Common Murre Sites

1996 1997 1998 1999 2000 2001 2002 2003 2

Year

TerritorialBreeding

Figure 7. Numbers of Common Murre breeding and territorial sites on Devil’s Slide Rock, 1996-2004.
37

0

20406080

100120140160

No. Common Murre sites

1996 1997 1998 1999 2000 2001 2002 2003 20

Year

Figure 8. Number of Common Murre breeding and territorial sites within and outside of decoy pSlide Rock, 1996-2004.

Outside of PlotWithin Decoy Plot
38

Figure 9. Seasonal attendance of Common Murres at Devil's Slide Rock, 11 November 2003 to 11 August 2004. Attendance is reported as an average of t

consecutive counts. Dashed line indicates pre-season (prior to 16 April).

0

50

100150200250300350

11/11

11/25

12/9

12/23

1/6

1/20

2/3

2/17

3/2

3/16

3/30

4/13

4/27

5/11

5/25

6/8

6/22

No. of Murres
39

 Common Ravens seen per scan

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

4/174/24

5/15/8

5/155/225/29

6/5

6/126/196/26

7/3

7/107/177/247/31

Date

Average no. per sca

n

 Common Murres seen per scan

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

4/174/24

5/15/8

5/155/225/29

6/5

6/126/196/26

7/3

7/107/177/247/31

Date

Average no. per sca

n

Figure 10. Seasonal attendance of Common Ravens and Common Murres at San Pedro Rock, 17

April to 31 July 2004. Data are presented as the average number of birds seen per 10 minute scan

during two hour watches.
40

CRM Subcolony 02 seasonal attendance 2004

0

50

100

150

200

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

CRM Subcolony 03E seasonal attendance 2004

0

50

100

150

200

250

300

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

CRM Subcolony 03W seasonal attendance 2004

0

20

40

60

80

100

120

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

BM227X 02 Esselen seasonal attendance 2004

0

50

100

150

200

250

300

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

Figure 11. Seasonal attendance patterns of Common Murres at BM227X subcolony 02 (Esselen) and

Castle Rocks and Mainland subcolonies 02, 03 East, and 03 West, 8 April to 29 July 2004. Dashed

line indicates attendance after arrival of a juvenile Brown Pelican on 24 June (see Disturbance).
41

CRM Subcolony 04 seasonal attendance 2004

0

100

200

300

400

500

600

700

800

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

CRM Subcolony 05 seasonal attendance 2004

0

5

10

15

20

25

30

35

40

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

CRM Subcolony 07 seasonal attendance 2004

0

50

100

150

200

250

300

350

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

Figure 12. Seasonal attendance patterns of Common Murres at Castle Rocks and Mainland

subcolonies CRM 04, 05, and 07, 8 April to 29 July 2004. Dashed line indicates attendance after

arrival of a juvenile Brown Pelican on 24 June (see Disturbance).
42

HPR Subcolony 01 seasonal attendance 2004

0

20

40

60

80

100

120

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

HPR Subcolony 02 Hump seasonal attendance 2004

0

20

40

60

80

100

120

140

160

180

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

HPR Subcolony 02 Ledge seasonal attendance 2004

0

50

100

150

200

250

300

4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29

Date

No. Common Murres

Figure 13. Seasonal attendance patterns of Common Murres at Hurricane Point Rocks subcolony

01, 02 Ledge, and 02 Hump, 8 April to 29 July 2004. Dashed line indicates attendance after arrival

of a juvenile Brown Pelican on 24 June (see Disturbance).
43

Area 1

Area 2

Area 3

Area 4

Area 5

Area 8

Area 9

Area 10

Area 11

Area 1

Area 2

Area 3

Area 4

Area 5

Area 8

Area 9

Area 10

Area 11

Figure 14. Survey areas from boat survey of seabird colonies in the San Pedro Rock to Devil’s Slide

areas, 18 June 2004.
44

2004 PICTORIAL HIGHLIGHTS

Figure 15. Aerial overview photograph of

Devil’s Slide Rock, 3 March 2004.

Figure 16. Aerial overview photograph of

Devil’s Slide Rock, 25 May 2004.

Figure 17. Prospecting Common Murre

among decoys on San Pedro Rock, 21 June

2004. 

Figure 18. Pair of Common Ravens attracted

to mirrors on San Pedro Rock, 6 June 2004.
45

Figure 19. View to southwest from Castle

Pullout of raven nesting cliff at Castle

Mainland, 2004. Arrow indicates approximate

location of nest.

Figure 20. Common Raven with a murre egg,

Castle Rocks subcolony 04, May 2004.

Figure 21. “Right” side of CRM-04

productivity plot, 12 June 2004.

Figure 22. Juvenile Brown Pelican on “right”

side of CRM-04 productivity plot during

disturbance event, late June 2004. Note the

murre chick near the pelican’s tail. 
46

Table 1. Common Murre productivity at Devil's Slide Rock (DSR) and Castle Rocks and Mainland

(CRM), 2004.

Colony/

Plot

# of Sites

Monitored

# of Egg

Laying

Sites

# of

Eggs

Laid

# of Eggs

Hatched Hatching

Success1

# of

Chicks

Fledged

Fledging

Success2

Chicks

Fledged

per Pair

DSR 313 190 201 142 70.6% 133 93.7% 0.70

CRM03 East

0 0 00 0 0 0 0

CRM04

106 85 89 54 60.7% 1 1.9% 0.01

1

 Hatching success is defined as the number of eggs hatched per eggs laid (includes both first and

replacement clutches).

2

 Fledging success is defined as the number of chicks fledged per eggs hatched (includes both first

and replacement clutches).

 Table 2. Non-anthropogenic disturbances incidentally observed at the Castle/Hurricane Colony

Complex, 2004. Data listed includes: mean number and range of murres/eggs/chicks disturbed or

lost per event, and the number of events.

Source

Disturbance

Events 

Average # of

Murres Disturbed

(range)

Egg

Loss

Chick

Loss

# of Disturbance

Events/hr

Common

Raven

184 89.5 

(1-350) 37 7 0.397

Brown

Pelican 97 111.3 

(12-400) 61 212 0.209

Western

Gull

4 35.5 

(31-40) 2 0 0.008

Peregrine

Falcon

2 120 

(40-200) 0 0 0.004

Turkey

Vulture

1 50 

(50) 0 0 0.002

Unknown 14 37.2 

(15-85) 0 0 0.03

Total 302 93.7 

(1-400) 45 28 0.653

 1 Egg loss due to Common Raven and Western Gull predation (see Table 3) 2 Chick loss due to Common Raven, Western Gull and Brown Pelican predation (see Table 3).
47

Table 3. Common Murre egg and chick loss on Castle Rocks and Mainland, subcolony 04 during

Brown Pelican disturbances, 24 June to 2 July 2004.

Source Egg

Depredation

Chick

Depredation

Chick 

Displacement

Common

Raven 5 15 0

Western

Gull 1 3 0

Brown

Pelican 02 11

Total 6 20 1

1 Chick was kicked from the rock by a murre during a flushing event.

Table 4. Aircraft sightings, boat sightings, and resulting disturbances incidentally observed at

Devil’s Slide Rock, 2004.

Source # of Aircraft

or Boats in

area

# of

Aircraft or

Boats/hr

# of

Disturbance

Events

# of

Disturbance

Events/hr

Average # of

Birds Disturbed 

(range)

Plane 66 0.107 0 0 0

Helicopter 58 0.094 7 0.011 11.7 

(2-50)

Boat 23 0.037 1 0.002 3 

Total 147 0.238 8 0.013 10.6 

(2-50)
48

Table 5. Brandt’s Cormorant breeding phenology and reproductive success at Devil’s Slide Rock and Mainland, 

Subcolony # of sites monitored Mean laying date (range; n) Mean hatching date (range; n) Mean # of eggs per site (range; n) Mean # of chicks per site (range; n) Me

fle

Devil’sSlide Rock 91

12 May

(15 Apr - 26 June;

n=82)

10 June 

(23 May - 17 June;

n=74)

3.3

(2-4; n=63)

2.3

(0-4; n=90)

MainlandSouth 61

4 May

(10 Apr - 29 May;

n=57)

5 June

(14 May - 28 June;

n=56)

3.4

(2-5; n=59)

2.7

(0-4; n=59) 

Turtlehead 24 6 May (12 Apr - 21 May;

n=24)

7 June

(27 May - 21 June;

n=24)

3.7

(2-5; n=23)

2.9

(1-4; n=24)

Total 176

8 May

(10 Apr - 26 June;

n=163)

7 June

(14 May - 28 June;

n=154)

3.4

(2-5; n=145)

2.5

(0-4; n=173)

(
49

Table 6. Numbers of Brandt’s Cormorant poorly-built nests (PBN), fairly-built nests (FBN), and well-built nests Devil’s Slide Rock and Mainland colony, 2004.

Subcolony Nest type 17 Apr 27 Apr 9 May 17 May 31 May 10 Jun 22 Jun 

DSR

PBN 5 8 3 2 0 7 1 

FBN 4 3 8 2 0 4 1 

WBN 8 4 44 48 65 66 79 

MainlandSouth

PBN 7 5 1 1 0 1 0 FBN 12 7 8 5 0 0 1 

WBN 3 7 64 67 81 78 83 

April’s Finger

PBN 0 n/a 2 2 0 0 0 FBN 1 n/a 3 1 0 0 0 

WBN 0 n/a 4 6 8 9 8 

Turtlehead

PBN 2 0 1 0 0 0 0 FBN 0 0 4 2 0 0 0 

WBN 0 0 20 22 24 24 25 
50

Table 7. Numbers of Brandt’s Cormorant poorly-built nests (PBN), fairly-built nests (FBN), and well-built nests Castle/Hurricane Colony Complex, 2004. Not all subcolonies were counted on each day.

Subcolony Nest

type

16

Apr

22

Apr

30

Apr

7

May

14

May

18

May

20

May

9

Jun

18

Jun

25

Jun

CR06S-S

PBN 3 n/a 0 0 0 n/a 0 n/a 0 n/a FBN 2 n/a 0 0 0 n/a 0 n/a 0 n/a 

WBN 3 n/a 9 29 18 n/a 21 n/a 20 n/a 

CR07

PBN 1 0 0 0 0 n/a n/a 0 0 0 FBN 2 2 0 0 0 n/a n/a 0 0 0 

WBN 1 3 6 6 6 n/a n/a 6 6 4 

CR09

PBN 11 0 0 n/a 0 n/a 0 0 0 n/a FBN 14 4 2 n/a 0 n/a 0 0 0 n/a 

WBN 4 11 24 n/a 15 n/a 62 58 41 n/a 

BM227X02

PBN 21 1 0 1 0 0 2 1 0 n/a FBN 19 2 1 7 5 2 3 0 0 n/a 

WBN 52 19 34 59 42 44 120 101 94 n/a 

H02

PBN 3 0 0 0 0 0 0 1 0 0 FBN 7 4 0 4 0 0 1 0 0 0 

WBN 7 15 17 18 19 20 20 27 25 19 
51

Table 8. Summary of aerial photograph counts of Common Murres (COMU), Brandt’s Cormorants (BRCOCormorants (DCCO) at sample central California breeding colonies, 2004.

Colony Name CCN1 USFWSCN2 Date COMU

Brandt’s Cormorant 

Birds Nests Sites Birds 

Point Reyes MA-374-01 429-001 05/25/04 24,437 580 61 721Point Resistance MA-374-03 429-024 05/25/04 4,246 14 0 33Miller’s Point Rocks MA-374-04 429-002 05/25/04 904 148 9 191Double Point Rocks MA-374-05 429-003 05/25/04 9,472 164 11 334North Farallon Islands SF-FAI-01 429-051 05/25/04 43,071 51 9 139

South Farallon Islands SF-FAI-02 429-052 05/24/04 76,287 8,507 347 10,677 Alcatraz Island SFB-SF-11 429-036 05/25/04 0 789 0 993Lobos Rock & Land’s End SF-374-02 429-029 05/25/04 0 119 0 185Seal Rocks SF-374-03 429-009 05/25/04 0 0 0 131Devil’s Slide Rock & Mainland SM-372-03 429-014 05/25/04 291 346 11 502Año Nuevo Island SM-370-04 429-023 05/27/04 0 1,639 9 2,486

Bench Mark-227X MO-362-18 454-029 05/27/04 323 222 2 237

Castle Rocks & Mainland MO-362-19 454-010 05/27/04 1,737 171 0 198Hurricane Point Rocks MO-362-20 454-011 05/27/04 804 34 1 39TOTAL 161,572 12,784 460 16,866 

1 CCN = California Colony Number 2 USFWSCN = U.S. Fish and Wildlife Service Colony Number.
52

Table 9. Numbers of Pelagic Cormorants, Western Gulls, Pigeon Guillemots, and Black Oystercatchers counted a

a boat survey between San Pedro Rock and Pillar Point, 18 June 2004. ND, no data.

Colony Name Area

Pelagic Cormorant

 Nest Bird

 Western Gull 

 Nest Bird

 Pigeon Guillemot 

Land H2O Total

 Black Oyst

Nest Bird (land) B

San Pedro Rock North side 0 0 1 1 ND 37 37 0 0  South side 0 0 5 ND 0 40 40 1 ND  Total 0 0 6 ND ND 77 77 1 0 San Pedro Point South side 0 0 0 0 2 0 2 0 0  Area 10 0 0 0 0 4 4 0 0  Total 0 000 24 6 0 0Devil’s Slide Rk. & Mainland Area 9 (“Pipe Point”) 0 0 0 0 8 8 0 0  Area 8 0 0 1 2 0 0 0 0 0  Turtlehead 31 1 0 000 0 0 0 

 Devil’s Slide Rock 0 0 2 2 0 0 0 0 0  Area 5 (Turtlehead Cove) 7 10 0 0 ND 62 62 0 0  Area 4 2 4 1 2 0 0 0 0 0  Area 3 4 7 0 0 0 0 0 0 0  Area 2 22 28 0 2 0 19 19 0 0  Area 1 19 33 0 0 0 8 8 0 0  Total 57 83 4 8 --- 97 97 0 0 

Pillar Point 0 0 0 0 0 1 1 0 0 

1 Seasonal total. One active nest remained 17 June.2 May include double counts of some birds since all birds were flying.
53

Table 10. Numbers of Pelagic Cormorant, Western Gull, and Black Oystercatcher nests and Pigeon

Guillemot birds counted at the Castle/Hurricane Colony Complex, 2004.1

Colony/

Subcolony

Pelagic

Cormorant

Western

Gull 

Black

Oystercatcher

Pigeon

Guillemot

Bench Mark- 227X

 BM-02 (Esselen Rk.) 0 2 0 0

 BM-05 (Rk. W. of Sub. 02) 0 1 0 0

 BM-06 (Slea Stack) 0 1 0 0

 Total 0 4 0 0

Castle Rocks & Mainland

 CRM-01 0 1 1 -

 CRM-02 0 1 0 -

 CRM-03A (Rock 03 West) 0 0 0 -

 CRM-03B (Rock 03 East) 0 1 1 -

 CRM-04 0 1 0 -

 CRM-05 0 1 0 -

 CRM-06 0 12 0 -

 CRM-07 1 0 0 -

 CRM-09 4 0 0 -

 CRM-10 (Rk. SE of CRM-01) 0 1 0 -

 CRM-11 (Rk. E. of CRM-03B) 0 1 0 -

 Total 5 7 2 133

Hurricane Point Rocks

 HPR-01 (North Rock) 0 1 0 0

 HPR-02 (South Rock) 1 12 0 43

 HPR-03 0 4 0 0

 Total 1 17 0 43

1

 Cormorant, gull, and oystercatcher nest counts from 9 June 2004 survey, unless otherwise

indicated.

2

 Count from aerial photographic survey, 27 May 2004.

3

 Seasonal high total from sea surface scans and colony counts. High count at CRM from 1 July

and at HPR 12 July, respectively. 
54

Appendix 1. Raw counts by subcolony of Common Murre birds and Brandt’s and Double-crested Cormorant nefrom aerial photographic surveys of central California colonies, 2004. SC# = Subcolony Number.____________________________________________________________________________________________________________________________________________________________________________________________________

Common Brandt’s Cormorant Doubl

 Date Colony Name SC# Subcolony Name Murre Nest Site Bird Nes__________________________________________________________________________________________________5/25/2004 Point Reyes 03B Lighthouse Rock 15100 0 0 0 0 5/25/2004 Point Reyes 03C NW Lighthouse Cliffs 1049 0 0 0 0 5/25/2004 Point Reyes 03D Aalge Ledge 0 0 0 0 0 5/25/2004 Point Reyes 03E The Bulb 309 0 0 0 0 5/25/2004 Point Reyes 03F SW Lighthouse Cliffs 94 0 0 0 0 5/25/2004 Point Reyes 04 S Lighthouse Cliffs 296 0 0 1 0 5/25/2004 Point Reyes 05B Boulder Rock 1807 0 0 0 0 5/25/2004 Point Reyes 05C Pebble Point 327 0 0 0 0 5/25/2004 Point Reyes 08A Trinity Point 15 247 44 316 0 5/25/2004 Point Reyes 09A Cliff Colony West 104 255 2 278 0 5/25/2004 Point Reyes 10A Northwest Rock 150 0 0 0 0 5/25/2004 Point Reyes 10B Flattop 1040 0 0 0 0 5/25/2004 Point Reyes 10C Middle Rock 874 0 0 0 0 5/25/2004 Point Reyes 10D East Rock 246 0 0 0 0 5/25/2004 Point Reyes 10E Beach Rock 257 0 0 0 0 5/25/2004 Point Reyes 10H Tim Tam 229 0 0 0 0 5/25/2004 Point Reyes 11B Face Rock 429 0 0 0 0 5/25/2004 Point Reyes 11E Mainland E. of Spine 0 10 5 20 0 5/25/2004 Point Reyes 13 Cone Rock 2028 0 0 0 0 5/25/2004 Point Reyes 14B Subcolony 14B 78 3 7 16 0 5/25/2004 Point Reyes 14D Miwok Rock 5 42 1 53 0 5/25/2004 Point Reyes 14E Miwok Mainland 0 23 2 33 0 5/25/2004 Point Reyes 19 Subcolony 19 0 0 0 4 0 5/25/2004 Point Resistance 02 Point Resistance 4246 14 0 33 0 5/25/2004 Miller's Point Rocks 01 North Rock 203 2 0 2 0 5/25/2004 Miller's Point Rocks 02 South Rock 701 146 9 189 0 5/25/2004 Double Point Rocks 01 Stormy Stack 9472 164 11 295 0 5/25/2004 Double Point Rocks 99 Rock N. of Stormy Stack 0 0 0 39 0 5/25/2004 North Farallon Islands 01 North Islet 6955 0 7 24 0 5/25/2004 North Farallon Islands 02 West Islet 13682 30 1 67 0 5/25/2004 North Farallon Islands 03 East Islet 14729 19 1 26 0 5/25/2004 North Farallon Islands 04 South Islet 7705 2 0 22 0 5/25/2004 South Farallon Islands 01 Southeast Farallon Island 31908 5966 273 7357 0 5/25/2004 South Farallon Islands 02 West End Island 30416 2479 71 3219 561 5/25/2004 South Farallon Islands 03 The Islets 12156 62 3 95 0 5/25/2004 South Farallon Islands 04 Saddle Rock 1807 0 0 6 0 _____________________________________________________________________________________________________________
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Appendix 1 (continued).____________________________________________________________________________________________________________________________________________________________________________________________________

Common Brandt’s Cormorant Doubl

 Date Colony Name SC# Subcolony Name Murre Nest Site Bird Nes__________________________________________________________________________________________________5/25/2004 Alcatraz Island 01 Alcatraz Island 0 789 0 993 0 5/25/2004 Lobos Rock and Lands End 04 Lobos Rock 0 0 0 14 0 5/25/2004 Lobos Rock and Lands End 06 Nearshore Rock 0 119 0 171 0 5/25/2004 Seal Rocks 01 Seal Rocks 0 0 0 131 0 5/25/2004 Devil's Slide Rock & Mainland 01 Devil's Slide Rock 291 105 0 153 0 5/25/2004 Devil's Slide Rock & Mainland 02 April's Finger 0 11 0 12 0 5/25/2004 Devil's Slide Rock & Mainland 05 Mainland South/Turtlehead 0 230 11 303 0 5/25/2004 Devil's Slide Rock & Mainland 99 Elizabeth Rock 0 0 0 34 0 5/27/2004 Año Nuevo Island 01 Año Nuevo Island 0 1639 9 2486 0 5/27/2004 Bench Mark-227X 02 Esselen Rock 323 222 2 237 0 5/27/2004 Castle Rocks & Mainland 02 Rock 02 297 0 0 0 0 5/27/2004 Castle Rocks & Mainland 03A Rock 03 West 123 0 0 0 0 5/25/2004 Castle Rocks & Mainland 03B Rock 03 East 0 0 0 0 0 5/27/2004 Castle Rocks & Mainland 04 Rock 04 675 0 0 0 0 5/27/2004 Castle Rocks & Mainland 05 Rock 05 27 0 0 0 0 5/27/2004 Castle Rocks & Mainland 06B Mainland 06 South 0 47 0 53 0 5/27/2004 Castle Rocks & Mainland 07 Rock 07 615 18 0 25 0 5/27/2004 Castle Rocks & Mainland 08 0 0 32 0 35 0 5/27/2004 Castle Rocks & Mainland 09 0 0 74 0 85 0 5/27/2004 Hurricane Point Rocks 01 Rock 01 157 0 0 0 0 5/27/2004 Hurricane Point Rocks 02 Rock 02 647 34 1 39 0 __________________________________________________________________________________________________________________________________________________________________________________________________________________________