United States

Department

of Agriculture

Forest Service

Rocky Mountain

Research Station

General Technical

Report RMRS-GTR-142

September 2005

Assessment of Native Species

and Ungulate Grazing in the

Southwest: Terrestrial Wildlife

Patrick W. Zwartjes

Jean-Luc E. Cartron

Pamela L. L. Stoleson

Walter C. Haussamen

Tiffany E. Crane
The use of trade or firm names in this publication is for reader information and does not

imply endorsement by the U.S. Department of Agriculture of any product or service

Abstract ______________________________________

Zwartjes, Patrick W.; Cartron, Jean-Luc E.; Stoleson, Pamela L. L.; Haussamen, Walter C.;

Crane, Tiffany E. 2005. Assessment of Native Species and Ungulate Grazing in the

Southwest: Terrestrial Wildlife. Gen. Tech. Rep. RMRS-GTR-142. Fort Collins, CO: U.S.

Department of Agriculture, Forest Service, Rocky Mountain Research Station. 74 p. plus CD.

Range managers in the Southwestern States are increasingly being required to develop

management strategies that take into consideration the conservation of wildlife populations.

However, information on many aspects of the fundamental biology and impacts of grazing on

individual species is still lacking in the scientific and government literature. This report

documents a project designed to assemble this information for terrestrial wildlife in Arizona

and New Mexico that have the potential to be negatively impacted by grazing or range

management practices. To achieve this, a two-stage panel process was developed that

employed a variety of wildlife experts to create a list of potentially vulnerable species and to

develop an informational database. Panelists first reviewed and assessed all terrestrial

vertebrates in the region to develop an initial list. In the second stage, the panelists refined the

list, reviewed published information drafted into individual species accounts, and then

augmented these accounts with information from their own experience and observations. The

resulting database contains accounts for 305 species and subspecies of amphibians, reptiles,

birds and mammals, including a computer database that allows managers to search and query

the species accounts based on geographic distribution as well as shared ecological and life

history characteristics.

Keywords:Arizona, grazing effects, New Mexico, range management, Southwest, terrestrial

wildlife, ungulate grazing, wildlife management

Acknowledgments ______________

The publication of this project represents the contributions of many individuals who worked on the initial

conceptualization and development of the entire Southwest grazing assessment, as well as the writing and editing

of the final product. The authors wish to first express our

appreciation to all the panel participants for sharing their

time and expertise. This project was initiated by Richard

Holthausen (USDA Forest Service, Washington, DC),

Sandy Boyce (USDA Forest Service, Region 3), and Debbie

Finch (Rocky Mountain Research Station - Albuquerque).

Region 3 provided important funding and other assistance

throughout the course of this project; special appreciation

goes to the contributions of Don DeLorenzo and Nick

Schmal (Wildlife, Fish, and Rare Plants) and Dave Stewart

(Rangeland Management). Additional financial, logistical,

and office support was provided by Rocky Mountain Research Station Research Work Unit-4351 in Albuquerque.

We also thank Richard Holthausen for contributing funding

from the USDA Forest Service Washington Office for

personnel and publication costs.

Bryce Rickel (Region 3) provided important technical

advice and assistance from the Regional Office. Other

participants throughout the development of this project

included Curt Flather, Darren Bender, and Will Moir

(RMRS, Flagstaff). Special thanks go to Bob Vahle and

Joan Scott of the Arizona Game and Fish Department for

their participation. We also recognize Ray Owen (who

developed the Microsoft Access database for the species

accounts) and the offices of RHI Consulting (Robert Half

International, Inc.) in Albuquerque for providing important

technical and logistical support. Michele Zwartjes and

Scott Stoleson contributed draft species accounts for the

Stage II panels, and David Whalen assisted in editing the

postpanel accounts. We also acknowledge the inputs of two

reviewers, Tom O’Neil of the Northwest Habitat Institute

(Corvallis, OR), and Mark Watson of New Mexico Department of Game and Fish (Santa Fe, NM). Finally, our thanks

to Louise Kingsbury, Lillie Thomas, Nancy Chadwick, and

the rest of the staff of the Rocky Mountain Research Station

Publishing Services (Ogden, UT) for their contributions in

producing the final report.
You may order additional copies of this publication by sending your

mailing information in label form through one of the following media.

Please specify the publication title and number.

Telephone (970) 498-1392

FAX (970) 498-1396

E-mail rschneider@fs.fed.us

Web site http://www.fs.fed.us/rm

Mailing Address Publications Distribution

Rocky Mountain Research Station

240 West Prospect Road

Fort Collins, CO 80526

Assessment of Native Species and Ungulate

Grazing in the Southwest: Terrestrial Wildlife

The Authors _____________________________________

Patrick W. Zwartjes worked as a postdoctoral Research Wildlife Biologist with the Rocky

Mountain Research Station in Albuquerque, NM, from 2000 to 2003. He received his

Ph.D. degree in biology from the University of New Mexico in 1997 and is currently a

biology instructor at Portland Community College, Portland, OR (patrick.zwartjes@pcc.edu

or pmmzwartjes@yahoo.com).

Jean-Luc E. Cartron completed his Ph.D. degree in biology at the University of New

Mexico in 1995 and worked as a postdoctoral Research Wildlife Biologist with the Rocky

Mountain Research Station in Albuquerque from 1997 to 2000. He is currently the Director

of the New Mexico office of the Drylands Institute, a nonprofit research organization, and

Assistant Research Professor at University of New Mexico (jlec@unm.edu).

Pamela L. L. Stoleson is a native of Aztec, NM, and earned a master’s degree in biology

from California State University at Fullerton. She worked for the Rocky Mountain

Research Station in Albuquerque from 1998 to 2002, and currently lives in Sugar Grove,

PA (stoleson@aol.com).

Walter C. Haussamen came to work for the Rocky Mountain Research Station in 2000

after retiring from a 25-year career with the New Mexico Department of Game and Fish

in Santa Fe. He has a master’s degree in wildlife management from New Mexico State

University in Las Cruces and is currently continuing his “retirement” as the Natural

Resources Manager for the U.S. Army Garrison, Combat Support Training Center in Fort

Hunter Liggett, CA (wally.haussamen@liggett-emh1.army.mil).

Tiffany E. Crane worked on this project for the Rocky Mountain Research Station from

2000 to 2001. She earned her bachelor’s degree in biology from Loyola University in New

Orleans, LA, and is currently working toward a law degree at Loyola (tcrane76@aol.com).
Contents________________________________________

Page

Introduction: ................................................................................................................. 1

Background ............................................................................................................... 1

Objectives ................................................................................................................. 2

Methods: The Panel Process ....................................................................................... 3

Stage I ...................................................................................................................... 3

Draft Species Accounts ............................................................................................ 3

Stage II ..................................................................................................................... 4

Species Account Database ....................................................................................... 4

Methods: Species Account Guide .............................................................................. 12

Species Account Elements: Definitions and Descriptions ...................................... 12

Results: Species List Generated by the Panel Process ............................................. 19

Stage I Results ....................................................................................................... 19

Stage II Results ...................................................................................................... 19

Results: Panel Findings on Grazing/Wildlife Interactions .......................................... 21

Interpreting the “Grazing Effects” Section ............................................................... 21

Summary of Panel Findings on Ecological Interactions with Wildlife ...................... 21

Summary .................................................................................................................... 37

References ................................................................................................................. 38

Appendix A—Grazing Assessment Panelists ............................................................ 44

Appendix B—Species Account Template .................................................................. 45

Appendix C—Annotated Bibliography of Major Information Sources ........................ 49

Appendix D—Species Removed by Stage II Panels ................................................. 51

Appendix E—Common Names and Scientific Names ............................................... 62

Appendix F—Users Guide to the Species Account Database CD ............................. 71
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 1

Introduction: ____________________________________________________

Background

The past few decades have seen the development of an

ecological and wildlife conservation ethic in the United States

that has increasingly manifested itself in Federal and State

laws. These laws have led to numerous conflicts with people

holding economic and social interests in the development and

use of natural resources. The relationship between wildlife

conservation and livestock grazing in the Southwest has been

particularly contentious. Although much of the discourse has

been driven by people with extreme views on both sides of the

argument, the USDA Forest Service and other public and

private groups have sought to balance these conflicting demands on the land and its resources. These groups are part of

a growing effort to approach livestock ranching with the aim of

using science-based management techniques that conserve

wildlife and their habitat (Brown and McDonald 1995).

Today’s range manager interested in management techniques that support both livestock and wildlife has an increasing number of resources available (for example, Sayre 2001).

However, information on the impacts of grazing on individual

wildlife species is still lacking in the scientific and government

literature, and many existing publications suffer from a variety

of problems of experimental design or failure to take into

account all influential environmental variables (Brown and

McDonald 1995; Curtin 2002; Jones 2000; Saab and others

1995; Stohlgren and others 1999; Holthausen personal communication). Of the “grazing effects” research that has been

published on species that occur in the Southwest, little focus

specifically on their occurrence in the ecosystems and communities of this region. This can lead to attempts to extrapolate

effects of grazing from regions outside the Southwest, which

in many cases has the potential to be highly misleading and in

some cases can lead to the recommendation of grazing regimes

that are detrimental.

Despite these challenges, range managers in the Southwest,

particularly those working in government agencies, are required to develop management strategies that take into consideration the conservation of wildlife populations. The focus is

frequently on legally protected wildlife, but increasingly includes other species in the interest of maintaining and protecting the wildlife resource on the landscape. Managers therefore

find themselves in the position of being expected to have

knowledge of the effects of various management actions on the

wildlife and habitat under their purview, despite the shortcomings of the informational resources noted above.

Many ecologists are beginning to focus on grazing effects on

a large, landscape-level scale. This view recognizes that a full

understanding of the ecological effects of grazing, particularly

in relatively homogeneous, widespread ecosystems (for example, desert grasslands), will likely require experimental

studies that take into account large-scale disturbance and

climate factors (Curtin 2002). However, at the smaller spatial

scales in which most land managers work, grazing can directly

affect wildlife through impacts to the specific ecological and

habitat needs of individual species. This small-scale approach

recognizes that there are certain specific parameters that must

be met for a species to persist within a local area, and that it is

possible to identify the ways that these parameters can be

affected by ungulate grazing as well as management actions.

We have based this assessment of wildlife and grazing

interactions in the Southwest on the specific ecological and

habitat requirements of individual species. As discussed above,

most terrestrial vertebrate species in the Southwest have not

been studied in the context of grazing effects. However,

information is available on the ecology, life history, and habitat

needs of most of these species, including the knowledge and

expertise of those individuals with extensive field experience

with these species. In the absence of direct scientific investigation of grazing effects on a species, this fundamental biological

information can be used to infer these effects from a species’

Assessment of Native Species

and Ungulate Grazing in the

Southwest: Terrestrial Wildlife

Patrick W. Zwartjes

Jean-Luc E. Cartron

Pamela L. L. Stoleson

Walter C. Haussamen

Tiffany E. Crane
2 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

habitat requirements. Such inference, while less desirable than

controlled studies, can form the basis for sound grazing management decisions when combined with additional information on climate, soils, vegetation and other critical components

of habitat.

Objectives

The primary objective of this effort is to provide land and

livestock managers of the Southwest with information on the

fundamental biology and habitat requirements of Southwestern wildlife. Rather than include all species, our approach

focuses on a subset of the region’s terrestrial vertebrate species

that have the potential to be negatively impacted by grazing or

range management practices.

There are two parts to this approach. The first part is to

review all the terrestrial vertebrate species of Arizona and New

Mexico in order to create a list of species that could be

negatively impacted. The second part is to collect data on each

species from a wide variety of sources (peer-reviewed literature, government reports, technical publications, and professional experts) in order to create a species account database.

The ultimate product is an easily accessible computerized

database that allows managers to search and query the collection of species accounts based on geographic distribution as

well as shared ecological, life history, and habitat characteristics among the species.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 3

Methods: The Panel Process _______________________________________

To meet the above objectives, information was gathered

from the peer-reviewed literature as well as a series of panels

comprising experts in various fields of wildlife ecology in the

Southwest. These panels, organized chiefly by taxonomic

group, played two major roles: first, to develop an initial list of

species that are potentially vulnerable to grazing or range

management actions (Stage I of the panel process), and second,

to review draft species accounts and supplement them with

information from the panelists’ personal knowledge and experience (Stage II of the process). The goal was to develop a

database of individual species accounts that provide as complete a picture as possible of the ecological and habitat needs

of each species and the possible ways in which they may be

affected by grazing.

Stage I

The objective of Stage I in the panel process was to review

each species from Arizona and New Mexico individually, and

from that review create an initial list of species for the database.

The panelists considered effects from both grazing and range

management practices. “Grazing” was considered to include

all impacts on the ecosystem resulting from ungulates (both

wild and domestic) feeding on vegetation. This could include

direct impacts from herbivory as well as indirect effects to

soils, water quality, fire regimes, and so forth. Impacts from

“range management” included various human-induced changes

to the environment resulting from the management of livestock

or range operations, such as the construction of stock tanks,

fences, and roads; the clearing of brush or trees to create

grasslands; development of natural springs for livestock; planting of exotic grasses; and other human impacts related to

raising and managing livestock.

Panelists were invited from a variety of organizations,

including universities, Federal and State government agencies,

and private organizations and consulting firms (appendix A).

Five panels were convened, organized as follows: (1) Herpetofauna (Reptiles and Amphibians), (2) Grassland/Desert Scrub

Birds, (3) Woodland Birds, (4) Riparian Birds, and (5) Mammals. A complete list of species for each group was compiled

using the Biota Information System of New Mexico (BISONM) database developed by the New Mexico Department of

Game and Fish; this database also contains taxa from Arizona

(NMDGF 2004a). The list was further refined through the use

of reference books of the Southwest (for example, Hoffmeister

1986; Hubbard 1978; Phillips and others 1964), and by having

the list reviewed by several of the expert panelists.

Subspecies were considered separately when they were

considered to have significant ecological differences (for example, disjunct distributions or habitat associations), if they

had been proposed as separate species, or when they were

listed as sensitive from a conservation standpoint (see also

Stage II process). Extirpated species were initially included for

review; however, it was ultimately decided to only include

these species if there was an active program to reintroduce

them back into the wild (for example, river otters, black-footed

ferrets, and gray wolves are included, whereas sage grouse and

bison are not).

For each species or subspecies, panelists were asked to note

information on the mechanisms of grazing effects, key habitat

components affected, part of life cycle affected, and general

appraisal of the status and degree of impact on each species. An

open round-table discussion allowed the panelists to share

their notes and observations on each species; the panelists were

then asked to select answers for three survey questions on the

direction, magnitude, and likelihood of the effects of grazing

on each species:

• Direction: Negative/Positive/Unknown/No effect

• Magnitude: Severe/Not Severe/Unknown

• Likelihood: Definite/Probable/Possible

The Stage I species selection process was intentionally

designed to be highly conservative, with a high rate of inclusion. The selections made by each panelist from the three

survey categories were entered into a spreadsheet for analysis;

to qualify for this initial inclusion, a species must have had one

of the two following selection combinations made by at least

one panelist:

• Direction: Negative, Magnitude: Severe, Likelihood: (any

selection)

• Direction: Negative, Magnitude: Unknown, Likelihood:

Definite

This focused the rejection process on species for which there

was general agreement that grazing had little if any effect, and

enabled some questionable species to remain on the list pending re-evaluation during Stage II. The complete Stage I list was

generated once all the panels were completed for each of the

five species groups.

Draft Species Accounts

Individual species accounts were drafted for each species on

the Stage I list. The basic species account template (see

appendix B and the “Species Account Guide” below) consists

of eight text narratives: Status/Trends/Threats, Distribution,

Breeding, Habitat, Season of Use, Diet, Grazing Effects, and

Fire Regime Requirements. These were developed using information gathered through a search of the technical literature,

including scientific journals, government technical reports,

books, survey data, and field guides (sources that were frequently used and proved to be particularly important are

summarized in appendix C). Interspersed among these narrative sections are a series of menus that present a variety of

selections to describe the ecological and life history parameters of the species in the database (defined below in the
4 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

“Species Account Guide”). All possible choices appeared in

each draft, with the intent that the Stage II panelists would

choose the items that apply to each particular species. The

menu selections play an important role in the electronic database, serving as search parameters that allow the user to create

a list of species that share an item or combination of items

under each menu (see appendix F).

Stage II

The objective of the Stage II panels was to review and amend

the narrative information in the draft accounts and to make

selections from the lists under each menu. In addition, the

Stage II panelists were asked to reject or add species, divide

species into subspecies accounts if appropriate, and designate

priority species in the database. Occasionally, a panel would

decide that no one on the panel had the knowledge or experience to review a particular species. In these cases, the panel

would recommend that we seek an outside reviewer to provide

the menu selections and comments normally provided by a

panel (see appendix A for outside reviewers, and tables 1 and

2 for species accounts information).

Review of Text—For each text section, the panelists made

the following contributions: (1) information based on their

own personal knowledge, research and/or field experience, (2)

editing of the language for accuracy and elimination of redundant or irrelevant information, and (3) suggestions for additional sources of information (journal or book references, other

experts to contact, and so forth). Information based on the

panelists’ personal knowledge, experience, or inference is

generally undocumented, and is identified in the text by the

citation “GP” for “Grazing Panel,” followed by the year the

panel was convened; for example, (GP 2000) or (GP 2001).

(Note: Stage I panels for all species groups were held in 1999;

thus, all citations following the general format of GP1999,

refer to information or comments provided in those panels.)

Some of this information carries a fairly high level of certainty,

especially when based on unpublished data or repeated observations made in the field. Information that is less certain or

based more on speculation is presented with the appropriate

qualifiers.

Menu Selections—Each Stage II panel made menu selections that represent appropriate descriptors for the particular

species under review. The panelists could choose from one to

all possible items in each list. The selections listed in a species

account represent a consensus selection made by the particular

panelists working on that species only. The “Panel comments”

boxes seen in the template (appendix B) were made available

to allow panelists to modify the definition of a selected term or

to provide additional information. These boxes only appear in

the final account if they were utilized by the panelists; all

information in these boxes is attributable to the Stage II panel

unless otherwise indicated.

Rejections and Additions—Because of the conservative

nature of the selection process in the first stage of panels, it was

expected that many species would be inappropriate to include

upon closer examination. Each Stage II panel was therefore

asked to consider the merits of inclusion for each species under

review and to reject any they deemed to be inappropriate for the

database. Panelists could also propose adding a species if they

felt that its absence was an important oversight (drafts were

then written for the additional species to be considered by a

future panel). Although the goal was to achieve consensus for

all rejections and additions, occasionally one or more panelists

would abstain from supporting a change that was made, but did

not object.

Multiple Subspecies Accounts—Panelists were also asked

to consider whether certain species should be divided into

individual accounts by subspecies. This was considered particularly important for subspecies that have markedly different

habitat requirements, thus requiring different selections under

the various menus. The utility for the user is that it eliminates

excess information for subspecies that do not occur in the area

or habitat of interest. In these cases, an account was typically

divided into multiple subspecific accounts during the panel

session, with panelists providing information and menu selections for each.

Designation of Priority Species—Stage II panelists were

also asked to determine whether each species should be designated as a “priority species” relative to the other species in the

database. These are taxa that, in the opinion of the panelists,

should receive greater consideration during development of

management strategies related to grazing. The Stage II panels

considered the “priority” designation under two landscapelevel scales: first, throughout the species’ entire distribution

within Arizona and New Mexico, and, second, only within

specifically identified key areas of abundance or distribution

(see “Species Account Guide” below for further descriptions).

Species Account Database

Each account was revised to incorporate all panel comments, as well as any additional literature, references, or other

information requested by the panelists. Menu selection lists are

reduced in their final versions to include only the selections

made by the panelists. The incorporation of information and

references provided by the panel frequently involved considerable revision of the draft; thus, an additional “Revision

Author” is identified at the end of each account as well as a

“Draft Author.” Panel participants are identified at the end of

each account, with Stage I panelists listed under the citation

“GP 1999” and Stage II panelists listed under grazing panel

citations with later years.

The species account database is provided here in an accompanying CD as a searchable database based in Microsoft

Access. In addition, each account can be viewed in two text

formats: Adobe PDF, for printing or on-screen viewing, and

Microsoft Word, which allows selective printing as well as

copying of text material. Appendix F provides further details

on accessing and using the searchable database and species

account files.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 5

Table 1—Numbers of species considered throughout the grazing assessment panel process, including the total number assessed

in Stage I, the number of species selected after Stage I, the number rejected or added in Stage II, the total number of species

included after Stage II, and the final number of accounts in the database (both species and subspecies).

Total assessed Selected Rejected Added Total after Total accounts

in Stage Ia after Stage I in Stage II in Stage II Stage IIb in databasec

Herpetofauna 166 (183) 31 –2 +1 30 (18%) 38

Birds

(grassland/ 127 (130) 49 –11 +1 39 (31%) 40

desert scrub)

Birds

(woodland) 125 (128) 60 –13 +4 51 (41%) 53

Birds

(riparian/ 249 (251) 87 –24 +8 71 (29%) 71

wetland)

Mammals 199 (274) 97 –21 +16 92 (46%) 103

Totals: 866 (966) 323 –71 +30 283 (33%) 305

a Many species were considered as multiple subspecies; the first number is species only, the number in parentheses includes the multiple

subspecies. b Total number of individual species and percent of original number of species from first column.

c Includes species that were divided into separate accounts for multiple subspecies.
6 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

(con.)

Table 2—Scientific and common names of the 305 terrestrial vertebrates in the grazing assessment database. Species and

subspecies are arranged taxonomically, first in three major groups (reptiles and amphibians, birds, and mammals), and

then by taxonomic order within each group. The last two columns state the panelists’ assessment as to whether a species

should be considered a priority (yes, no, or unknown) when developing a grazing strategy: first, throughout the species’

distribution in Arizona and New Mexico, and, second, only in key distribution, abundance, or management areas within

the species’ range.

Priority?

All Key

Genus Species Subspecies Common name areas areas

Reptiles and amphibians

Ambystoma tigrinum nebulosum Tiger Salamander NO NO

Ambystoma tigrinum stebbinsi Sonora Tiger Salamander YES YES

Rana blairi Plains Leopard Frog NO YES

Rana chiricahuensis Chiricahua Leopard Frog YES YES

Rana pipiens Northern Leopard Frog YES YES

Rana yavapaiensis Lowland Leopard Frog YES YES

Gopherus agassizi Desert Tortoise YES YES

Terrapene ornata Ornate Box Turtle NO YES

Kinosternon sonoriense Sonoran Mud Turtle NO NO

Kinosternon flavescens flavescens Yellow Mud Turtle NO YES

Kinosternon flavescens arizonense Southwestern Mud Turtle NO YES

Gambelia wislizenii Leopard Lizard NO NO

Phrynosoma douglasii Short-Horned Lizard NO YES

Sceloporus arenicolus Sand Dune Lizard YES YES

Sceloporus clarkii Clark’s Spiny Lizard NO NO

Sceloporus scalaris Bunch Grass Lizard YES YES

Sceloporus undulatus Prairie (Eastern Fence) Lizard NO NO

Cnemidophorus burti Canyon (Giant) Spotted Whiptail YES YES

Cnemidophorus inornatus arizonae Arizona Little Striped Whiptail YES YES

Cnemidophorus inornatus heptagrammus Trans-Pecos Little Striped Whiptail YES YES

Cnemidophorus inornatus juniperus Woodland Little Striped Whiptail UNK UNK

Cnemidophorus inornatus llanuras Plains Little Striped Whiptail YES YES

Cnemidophorus inornatus pai Pai Little Striped Whiptail YES YES

Eumeces gilberti arizonensis Arizona Skink UNK UNK

Coluber constrictor Yellowbelly Racer UNK YES

Lampropeltis triangulum Milk Snake UNK YES

Thamnophis eques Mexican Garter Snake YES YES

Thamnophis proximus Western Ribbon Snake YES YES

Thamnophis rufipunctatus Narrowhead Garter Snake YES YES

Crotalus atrox Western Diamondback Rattlesnake NO NO

Crotalus cerastes Sidewinder Rattlesnake NO NO

Crotalus lepidus klauberi Banded Rock Rattlesnake NO NO

Crotalus lepidus lepidus Mottled Rock Rattlesnake UNK UNK

Crotalus molossus Blacktail Rattlesnake NO NO

Crotalus scutulatus Mojave Rattlesnake NO NO

Crotalus willardi obscurus New Mexico Ridgenose Rattlesnake YES YES

Crotalus willardi willardi Arizona Ridgenose Rattlesnake YES YES

Sistrurus catenatus Massasauga YES YES

Birds

Botaurus lentiginosus American Bittern YES YES

Ixobrychus exilis Least Bittern YES YES

Ardea alba Great Egret NO YES

Egretta thula Snowy Egret NO YES

Butorides virescens Green Heron NO YES

Nycticorax nycticorax Black-Crowned Night-Heron NO YES

Plegadis chihi White-Faced Ibis NO YES

Dendrocygna autumnalis Black-Bellied Whistling-Duck YES YES

Aix sponsa Wood Duck NO YES
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 7

Anas strepera Gadwall YES YES

Anas americana American Wigeon YES YES

Anas cyanoptera Cinnamon Teal NO YES

Anas clypeata Northern Shoveler YES YES

Anas acuta Northern Pintail YES YES

Anas crecca Green-Winged Teal YES YES

Mergus merganser Common Merganser NO YES

Pandion haliaetus Osprey YES YES

Haliaeetus leucocephalus Bald Eagle YES YES

Circus cyaneus Northern Harrier YES YES

Accipiter cooperii Cooper’s Hawk UNK NO

Accipiter gentilis Northern Goshawk YES YES

Buteogallus anthracinus Common Black-Hawk YES YES

Parabuteo unicinctus Harris’ Hawk NO YES

Buteo albonotatus Zone-Tailed Hawk YES YES

Buteo regalis Ferruginous Hawk YES YES

Aquila chrysaetos Golden Eagle YES YES

Falco femoralis Aplomado Falcon YES YES

Falco peregrinus Peregrine Falcon NO NO

Tympanuchus pallidicinctus Lesser Prairie-Chicken YES YES

Meleagris gallopavo intermedia Rio Grande Wild Turkey NO YES

Meleagris gallopavo merriami Merriam’s Wild Turkey NO NO

Meleagris gallopavo mexicana Gould’s Wild Turkey YES YES

Callipepla squamata Scaled Quail NO NO

Colinus virginianus texanus Northern Bobwhite UNK UNK

Colinus virginianus ridgwayi Masked Bobwhite YES YES

Cyrtonyx montezumae Montezuma Quail YES YES

Laterallus jamaicensis coturniculus California Black Rail YES YES

Rallus longirostrus yumanensis Yuma Clapper Rail YES YES

Rallus limicola Virginia Rail YES YES

Porzana carolina Sora NO YES

Gallinula chloropus Common Moorhen YES YES

Numenius americanus Long-Billed Curlew NO YES

Gallinago gallinago Common Snipe NO YES

Patagioensis fasciata Band-Tailed Pigeon NO NO

Coccyzus americanus Yellow-Billed Cuckoo YES YES

Otus flammeolus Flammulated Owl NO NO

Megascops kennicottii Western Screech-Owl UNK UNK

Megascops trichopsis Whiskered Screech-Owl YES YES

Glaucidium gnoma Northern Pygmy-Owl NO NO

Glaucidium brasilianum cactorum Cactus Ferruginous Pygmy-Owl YES YES

Micrathene whitneyi Elf Owl NO YES

Athene cunicularia Burrowing Owl YES YES

Strix occidentalis lucida Mexican Spotted Owl YES YES

Aegolius acadicus Northern Saw-Whet Owl NO NO

Phalaenoptilus nuttalli Common Poorwill NO NO

Caprimulgus ridgwayi Buff-Collared Nightjar YES YES

Caprimulgus vociferus Whip-Poor-Will NO NO

Cynanthus latirostris Broad-Billed Hummingbird YES YES

Amazilia violiceps Violet-Crowned Hummingbird YES YES

Lampornis clemenciae Blue-Throated Hummingbird UNK YES

Eugenes fulgens Magnificent Hummingbird NO YES

Calypte costae Costa’s Hummingbird NO YES

Selasphorus platycercus Broad-Tailed Hummingbird NO NO

Trogon elegans Elegant Trogon YES YES

Table 2 (Con.)

Priority?

All Key

Genus Species Subspecies Common name areas areas

(con.)
8 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Melanerpes lewis Lewis’ Woodpecker NO NO

Melanerpes erythrocephalus Red-Headed Woodpecker NO YES

Melanerpes formicivorus Acorn Woodpecker NO YES

Melanerpes uropygialis Gila Woodpecker NO YES

Sphyrapicus thyroideus Williamson’s Sapsucker UNK YES

Sphyrapicus nuchalis Red-Naped Sapsucker UNK YES

Picoides villosus Hairy Woodpecker UNK YES

Colaptes auratus Northern Flicker NO NO

Colaptes chrysoides Gilded Flicker YES YES

Camptostoma imberbe Northern-Beardless Tyrannulet YES YES

Contopus cooperi Olive-Sided Flycatcher YES YES

Contopus pertinax Greater Pewee YES YES

Contopus sordidulus Western Wood-Pewee NO NO

Empidonax traillii extimus Southwestern Willow Flycatcher YES YES

Empidonax occidentalis Cordilleran Flycatcher NO YES

Empidonax fulvifrons Buff-Breasted Flycatcher YES YES

Sayornis nigricans Black Phoebe YES NO

Pyrocephalus rubinus Vermillion Flycatcher NO NO

Myiarchus cinerascens Ash-Throated Flycatcher NO NO

Myiarchus tyrannulus Brown-Crested Flycatcher NO NO

Myiodynastes luteiventris Sulphur-Bellied Flycatcher YES YES

Tyrannus melancholicus Tropical Kingbird YES YES

Tyrannus crassirostris Thick-Billed Kingbird YES YES

Pachyramphus aglaiae Rose-Throated Becard YES YES

Vireo bellii Bell’s Vireo YES YES

Vireo vicinior Gray Vireo YES YES

Vireo plumbeus Plumbeous Vireo NO NO

Vireo gilvus Warbling Vireo NO NO

Gymnorhinus cyanocephalus Pinyon Jay NO NO

Tachycineta thalassina Violet-Green Swallow NO YES

Poecile atricapillus Black-Capped Chickadee NO NO

Poecile sclateri Mexican Chickadee YES YES

Sitta canadensis Red-Breasted Nuthatch NO NO

Sitta carolinensis White-Breasted Nuthatch NO NO

Sitta pygmaea Pygmy Nuthatch YES YES

Certhia americana Brown Creeper NO YES

Thryomanes bewickii Bewick’s Wren NO NO

Troglodytes aedon House Wren NO NO

Cistothorus palustris Marsh Wren YES YES

Cinclus mexicanus American Dipper YES YES

Polioptila caerulea Blue-Gray Gnatcatcher NO NO

Polioptila melanura Black-Tailed Gnatcatcher UNK UNK

Sialia mexicana Western Bluebird UNK NO

Catharus ustulatus Swainson’s Thrush NO YES

Catharus guttatus Hermit Thrush NO NO

Dumetella carolinensis Gray Catbird YES YES

Toxostoma crissale Crissal Thrasher UNK UNK

Toxostoma lecontei LeConte’s Thrasher YES YES

Anthus spragueii Sprague’s Pipit YES YES

Phainopepla nitens Phainopepla YES YES

Peucedramus taeniatus Olive Warbler YES YES

Vermivora celata Orange-Crowned Warbler NO YES

Vermivora luciae Lucy’s Warbler YES YES

Dendroica petechia Yellow Warbler YES YES

Dendroica nigrescens Black-Throated Gray Warbler NO NO

Table 2 (Con.)

Priority?

All Key

Genus Species Subspecies Common name areas areas

(con.)
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 9

Dendroica graciae Grace’s Warbler YES YES

Oporornis tolmiei MacGillivray’s Warbler NO YES

Geothlypis trichas Common Yellowthroat NO NO

Wilsonia pusilla Wilson’s Warbler NO NO

Myioborus pictus Painted Redstart NO YES

Icteria virens Yellow-Breasted Chat NO NO

Piranga flava Hepatic Tanager NO NO

Piranga rubra Summer Tanager YES YES

Piranga ludoviciana Western Tanager NO NO

Pipilo chlorurus Green-Tailed Towhee NO NO

Pipilo maculatus Spotted Towhee NO NO

Pipilo aberti Abert’s Towhee YES YES

Aimophila carpalis Rufous-Winged Sparrow YES YES

Aimophila cassinii Cassin’s Sparrow NO YES

Aimophila botterii Botteri’s Sparrow YES YES

Spizella arborea American Tree Sparrow NO YES

Spizella passerina Chipping Sparrow NO NO

Spizella atrogularis Black-Chinned Sparrow NO YES

Pooecetes gramineus Vesper Sparrow NO NO

Amphispiza belli Sage Sparrow NO YES

Calamospiza melanocorys Lark Bunting NO YES

Passerculus sandwichensis Savannah Sparrow NO YES

Ammodramus savannarum Grasshopper Sparrow YES YES

Ammodramus bairdii Baird’s Sparrow YES YES

Melospiza melodia Song Sparrow NO YES

Melospiza lincolnii Lincoln’s Sparrow NO YES

Junco phaeonotus Yellow-Eyed Junco YES YES

Calcarius ornatus Chesnut-Collared Longspur NO YES

Cardinalis cardinalis Northern Cardinal NO NO

Cardinalis sinuatus Pyrrhuloxia NO NO

Pheucticus melanocephalus Black-Headed Grosbeak NO YES

Passerina caerulea Blue Grosbeak NO NO

Passerina amoena Lazuli Bunting YES YES

Passerina cyanea Indigo Bunting NO NO

Passerina versicolor Varied Bunting YES YES

Passerina ciris Painted Bunting YES YES

Spiza americana Dickcissel UNK UNK

Dolichonyx oryzivorus Bobolink YES YES

Sturnella magna lilianae Lilian’s Eastern Meadowlark YES YES

Xanthocephalus xanthocephalus Yellow-Headed Blackbird NO YES

Icterus spurius Orchard Oriole NO YES

Icterus cucullatus Hooded Oriole NO NO

Icterus bullockii Bullock’s Oriole NO NO

Icterus parisorum Scott’s Oriole YES YES

Carduelis psaltria Lesser Goldfinch NO NO

Mammals

Sorex arizonae Arizona Shrew YES YES

Sorex cinereus Cinereus (Masked) Shrew YES YES

Sorex merriami Merriam’s Shrew UNK UNK

Sorex monticolus Montane Shrew YES YES

Sorex neomexicanus New Mexico Shrew YES YES

Sorex nanus Dwarf Shrew NO YES

Sorex palustris Water Shrew YES YES

Sorex preblei Preble’s Shrew YES YES

Table 2 (Con.)

Priority?

All Key

Genus Species Subspecies Common name areas areas

(con.)
10 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Cryptotis parva Least Shrew YES YES

Notiosorex crawfordi (Crawford’s) Desert Shrew NO NO

Choeronycteris mexicana Mexican Long-Tongued Bat YES YES

Leptonycteris nivalis Mexican Long-Nosed Bat YES YES

Leptonycteris curasoae Southern Long-Nosed Bat YES YES

Lasiurus borealis Eastern Red Bat UNK UNK

Lasiurus blossevillii Western Red Bat YES YES

Lasiurus xanthinus Western Yellow Bat YES YES

Lasionycteris noctivagans Silver-Haired Bat UNK UNK

Euderma maculatum Spotted Bat YES YES

Idionycteris phyllotis Allen’s Big-Eared Bat YES YES

Canis lupus baileyi Mexican Gray Wolf YES YES

Vulpes velox Swift Fox YES YES

Vulpes macrotis Kit Fox YES YES

Vulpes vulpes Red Fox NO YES

Ursus americanus American Black Bear NO YES

Mustela erminea Ermine YES YES

Mustela frenata Long-Tailed Weasel YES YES

Mustela nigripes Black-Footed Ferret YES YES

Mustela vison Mink YES YES

Lontra canadensis Northern River Otter YES YES

Mephitis macroura Hooded Skunk YES YES

Puma concolor Cougar (Mountain Lion) NO YES

Lynx rufus Bobcat NO NO

Panthera onca Jaguar YES YES

Pecari tajacu Collared Peccary (Javelina) NO NO

Cervus elaphus nelsoni Rocky Mountain Elk YES YES

Odocoileus hemionus Mule Deer YES YES

Odocoileus virginianus texana Texas White-Tailed Deer YES YES

Odocoileus virginianus couesi Coues’ White-Tailed Deer YES YES

Antilocapra americana americana American Pronghorn YES YES

Antilocapra americana sonoirensis Sonoran Pronghorn YES YES

Ovis canadensis mexicana Mexican Desert Bighorn Sheep YES YES

Ovis canadensis nelsoni Nelson’s Desert Bighorn Sheep YES YES

Ovis canadensis canadensis Rocky Mountain Bighorn Sheep YES YES

Tamias canipes Gray-Footed Chipmunk YES YES

Tamias cinereicollis Gray-Collared Chipmunk NO YES

Tamias dorsalis Cliff Chipmunk NO NO

Tamias minimus Least Chipmunk NO YES

Tamias quadrivittatus Colorado Chipmunk NO YES

Marmota flaviventris Yellow-Bellied Marmot YES YES

Spermophilus lateralis Golden-Mantled Ground Squirrel NO NO

Spermophilus tridecemlineatus arenicola Pale Thirteen-Lined Ground Squirrel NO NO

Spermophilus tridecemlineatus blanca San Luis Thirteen-Lined Ground

 Squirrel YES YES

Spermophilus tridecemlineatus hollisteri Mescalero Thirteen-Lined Ground

 Squirrel YES YES

Spermophilus tridecemlineatus monticola White Mountains Thirteen-Lined

 Ground Squirrel YES YES

Cynomys gunnisoni Gunnison’s Prairie Dog NO YES

Cynomys ludovicianus Black-Tailed Prairie Dog NO YES

Sciurus arizonensis Arizona Gray Squirrel NO YES

Sciurus nayaritensis chiricahuae Chiricahua Mexican Fox Squirrel YES YES

Sciurus hudsonicus Red Squirrel NO YES

Thomomys talpoides Northern Pocket Gopher NO YES

Table 2 (Con.)

Priority?

All Key

Genus Species Subspecies Common name areas areas

(con.)
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 11

Thomomys umbrinus Southern Pocket Gopher UNK UNK

Cratogeomys castanops Yellow-Faced Pocket Gopher NO UNK

Perognathus flavus Silky Pocket Mouse NO YES

Chaetodipus hispidus Hispid Pocket Mouse YES YES

Dipodomys microps Chisel-Toothed Kangaroo Rat NO YES

Dipodomys ordii Ord’s Kangaroo Rat NO NO

Dipodomys spectabilis Banner-Tailed Kangaroo Rat YES YES

Castor canadensis American Beaver NO YES

Reithrodontomys fulvescens Fulvous Harvest Mouse YES YES

Reithrodontomys megalotis Western Harvest Mouse YES YES

Reithrodontomys montanus Plains Harvest Mouse NO NO

Peromyscus merriami Mesquite Mouse YES YES

Baiomys taylori Northern Pygmy Mouse YES YES

Sigmodon arizonae Arizona Cotton Rat YES YES

Sigmodon fulviventer Tawny-Bellied Cotton Rat YES YES

Sigmodon hispidus Hispid Cotton Rat YES YES

Sigmodon ochrognathus Yellow-Nosed Cotton Rat YES YES

Neotoma cinerea Bushy-Tailed Woodrat YES YES

Neotoma devia Arizona Woodrat NO YES

Neotoma lepida Desert Woodrat NO YES

Neotoma micropus Southern Plains Woodrat YES YES

Neotoma stephensi Stephen’s Woodrat NO YES

Clethrionomys gapperi Southern Red-Backed Vole NO NO

Phenacomys intermedius Western Heather Vole YES YES

Microtus longicaudus Long-Tailed Vole YES YES

Microtus mogollonensis Mogollon Vole YES YES

Microtus montanus Montane Vole YES YES

Microtus ochrogaster Prairie Vole YES YES

Microtus pennsylvanicus Meadow Vole YES YES

Ondatra zibethicus Muskrat YES YES

Zapus hudsonius luteus New Mexico Meadow Jumping Mouse YES YES

Zapus princeps Western Jumping Mouse YES YES

Ochotona princeps incana American Pika NO NO

Ochotona princeps nigrescens Goat Peak American Pika YES YES

Sylvilagus floridanus cognatus Manzano Mountains Eastern Cottontail YES YES

Sylvilagus floridanus hesperius Arizona Eastern Cottontail YES YES

Sylvilagus floridanus holzneri Holzner’s Eastern Cottontail YES YES

Sylvilagus floridanus llanensis Llano Eastern Cottontail NO NO

Sylvilagus nuttallii Mountain (Nuttall’s) Cottontail NO YES

Sylvilagus robustus Davis Mountains Cottontail YES YES

Lepus americanus Snowshoe Hare YES YES

Lepus callotis White-Sided Jackrabbit YES YES

Lepus townsendii White-Tailed Jackrabbit YES YES

Table 2 (Con.)

Priority?

All Key

Genus Species Subspecies Common name areas areas
12 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

The following user’s guide to the species accounts explains

the various elements and assists in the interpretation of the

inputs made by the panelists. The contents of each account

were crafted using specific guidelines and rules provided to the

panelists; thus, any user of these accounts should refer to these

descriptions when interpreting the informational content. Refer to the template illustrated in appendix B when reviewing the

following descriptions and discussions of the various species

account elements.

Species Account Elements: Definitions

and Descriptions

Scientific Name—This is the latest Latin scientific name for

a species or subspecies (listed as genus, species, and subspecies where warranted). In addition to cases where species were

divided into multiple subspecies accounts (for example, subspecies of Sylvilagus floridanus, the eastern cottontail), subspecific names were used only if (a) one subspecies was

potentially threatened by grazing whereas others were considered not to be (for example, Sturnella magna lilianae, Lilian’s

eastern meadowlark), or (b) there is only one subspecies in

Arizona/New Mexico, but it is an important taxa for conservation or other reasons (for example, Strix occidentalis lucida,

the Mexican spotted owl).

Common Name—The common name on an account is the

most frequently used English name for a species, based on a

standardized list by an authoritative organization when possible. For instance, the American Ornithologists’ Union has

created a list of standardized common names for all bird

species, most recently in AOU (1998). Common names for

mammals are less rigorously standardized; however, we have

used a standardized list created by the Smithsonian Institution

(used in Wilson and Ruff 1999). Common names for reptiles

and amphibians are based on authoritative texts (for example,

Degenhardt and others 1996).

Subspecific common names are even less standardized; a

standard common name is used when available (for example,

Mexican spotted owl), but other cases (such as the subspecies

of the eastern cottontail) relied on the advice and suggestions

of the panelists.

Legal Status (Menu)—Selections are based on status designations recognized under regulation, law, or treaty by various government organizations. Several species in the database

are regulated by Arizona and New Mexico as game animals;

however, for most species the take and/or collecting of individuals for hunting, commercial, educational, or research

purposes is also governed by State laws (for details, consult

AGFD 2004; NMDGF 2004b).

• BLM, AZ - Sensitive: listed as “sensitive” by the Department of the Interior, Bureau of Land Management, Arizona State Office.

Methods: Species Account Guide ___________________________________

• BLM, NM - Sensitive: listed as “sensitive” by the Department of the Interior, Bureau of Land Management, New

Mexico State Office.

• CITES - Appendix I: listed under the Convention on

International Trade in Endangered Species of Wild Flora

and Fauna (CITES). “Appendix I” species are considered

threatened with extinction; commercial international trade

is prohibited except for exceptional circumstances (CITES

2003).

• CITES - Appendix II: These species “are not necessarily

now threatened with extinction but ... may become so

unless trade is closely controlled. [Appendix II] also

includes so-called ‘look-alike species’, i.e. species of

which the specimens in trade look like those of species

listed for conservation reasons...” (CITES 2003).

• ESA - Endangered: species listed as “endangered” by the

U.S. Department of the Interior, Fish and Wildlife Service, under the Endangered Species Act.

• ESA - Threatened: species listed as “threatened” by the

U.S. Department of the Interior, Fish and Wildlife Service, under the Endangered Species Act.

• ESA - Warranted but Precluded: species for which the

U.S. Department of the Interior, Fish and Wildlife Service, has on file “sufficient information on biological

vulnerability and threats to support proposals to list them

as endangered or threatened. Issuance of proposed rules

for these taxa is precluded at present by other higher

priority listing actions...” (USDI Fish and Wildlife Service 1999: 57535).

• Migratory Bird Treaty Act: The Migratory Bird Treaty

Act of 1918 is the domestic law that affirms, or implements, the U.S. commitment to four international conventions (with Canada, Japan, Mexico, and Russia) for the

protection of a shared migratory bird resource. This act

decreed that the birds and their parts (including eggs,

nests, and feathers) are fully protected (USDI Fish and

Wildlife Service 2003). Despite the title, this statute

covers all native bird species with the exception of upland

game birds.

• Navajo - Endangered: species listed as “endangered” by

the Navajo Nation Tribal law.

• Navajo - Threatened: species listed as “threatened” by the

Navajo Nation Tribal law.

• Arizona - WSCA: species listed as either “endangered” or

“threatened” by the State of Arizona Game and Fish

Commission in the 1988 publication “Threatened Native

Wildlife in Arizona” (AGFD 1988). In 1995, the Arizona

Game and Fish Commission voted to change the name of

the list of species from “Threatened Native Wildlife” to

“Wildlife of Special Concern in Arizona” (WSCA); it

also voted to do away with all categories of endangered,

threatened, or candidate species. In 1996, a public review

draft of a new list of WSCA species was published
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 13

(AGFD 1996), but no action by the Arizona Game and

Fish Commission has been taken to legally change the

complement of the list. Thus, the legal list remains the

species published in AGFD (1988), but by the actions in

1995 they are no longer considered endangered or threatened, only categorized as “WSCA” (Schwartz, personal

communication 2001).

• New Mexico - Endangered: species listed as “endangered” by the State of New Mexico Department of Game

and Fish, under the authority of the Wildlife Conservation

Act (NMSA 17-2-37 through 17-2-46, 1978).

• New Mexico - Threatened: species listed as “threatened”

by the State of New Mexico Department of Game and

Fish, under the authority of the Wildlife Conservation Act

(NMSA 17-2-37 through 17-2-46, 1978).

• USFS Region 3 - Sensitive: the Southwestern Region of

the USDA Forest Service places species on a list of

“sensitive” species according to their vulnerability to

decline and their potential for being placed on the “threatened” or “endangered” list. The Forest Service defines

sensitive species as those plant and animal species identified by a Regional Forester for which population viability is a concern, as evidenced by significant current or

predicted downward trends in population numbers or

density, or significant current or predicted downward

trends in habitat capability that would reduce a species’

existing distribution; different regions use different criteria for designating “sensitive” species.

• None: this species has no legal designation among the

selections provided under this menu. Other regulations,

such as those governing hunting or fishing, may apply to

this species.

Distribution (Menu)—Selections here indicate notable aspects of the species’ geographic range, particularly in regards

to endemism and limits to the species’ distribution in Arizona

and/or New Mexico.

• Endemic to Arizona: the species occurs only in Arizona,

and no where else globally.

• Endemic to New Mexico: the species occurs only in New

Mexico, and no where else globally.

• Endemic to Arizona and New Mexico: the species occurs

only in Arizona and New Mexico, and no where else

globally.

• Not restricted to Arizona or New Mexico: the species’

geographic range includes areas outside of Arizona and

New Mexico; it is not endemic to either State or the

region.

• Northern limit of distribution: the northern limit of the

species’ geographic range occurs in Arizona, New Mexico,

or both. Migratory species (such as many birds in the

database) may have either breeding or wintering distributions with northern limits in Arizona or New Mexico; this

item will also be selected for situations where this occurs.

This definition also applies to the following three choices,

using their respective geographic references.

1. Southern limit of distribution

2. Eastern limit of distribution

3. Western limit of distribution

Ecological Role (Menu)—Selections here indicate the role

this species plays in its ecological community. Selections that

refer to the general diet of the species are indicated by the word

“dietary.” More than one of these “dietary” selections may be

made if the species seasonally changes the emphasis of its diet

(for example, birds that are primarily insectivorous in the

spring and summer, and then switch to being granivorous in the

winter).

• Commensal/mutualistic: a species that has an important

interaction with another species in the community in

which (a) it or the other species benefits while the other is

neither harmed nor benefits (commensal), or (b) both

species benefit from the interaction (mutualistic).

• Granivore: (dietary) consumes primarily seeds.

• Herbivore: (dietary) consumes primarily plant material,

including both grazers and browsers.

• Hybridization/intergradation: this species has important

interactions in which it frequently hybridizes with one or

more other species.

• Key predator: (dietary) consumes primarily other animals. A “key” predator was defined as one that must

exclusively hunt, kill, and feed on other animals (as

opposed to occasional or opportunistic predation).

• Insectivore: (dietary) consumes primarily insects, spiders, and other arthropods.

• Key prey species: a species that serves as primary or

major prey for another species.

• Key vector: a species that is an important carrier of

disease or parasitic organisms.

• Omnivore: (dietary) consumes a wide variety of food

types, often opportunistically, and cannot be categorized

as primarily feeding on one type or another.

• Parasitic: a species that interacts with one or more other

species such that it receives a benefit while causing harm

or a detriment to the other species.

• Pollinator: functions as a distributor of pollen among the

flowers of one or more plants species (primarily hummingbirds and bats).

• Primary cavity nester: a species that nests, roosts, or dens

in a tree or ground cavity that it excavates itself; old

cavities may be subsequently used by other species.

• Scavenger/detritivore: (dietary) feeds on dead and/or

decomposing organic matter, primarily the carcasses of

dead animals.

• Secondary cavity nester: a species that nests, roosts, or

dens in a tree or ground cavity that either occurs naturally

or was previously excavated by another species. It may do

some minor excavations but does not normally construct

its own cavity.

Status/Trends/Threats (Narrative)—This text section reports information on the general status of the species (both

globally and in the Southwest), and information regarding
14 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

trends in population numbers or sizes. This section may also

have information on historical trends in the Southwest, changes

in species’ status or nomenclature, legal issues regarding this

species, research or information on reproductive capabilities,

and other information that may be regarded as “status” or

“trends.” If the account is for a subspecies, information regarding the species as a whole is usually included as well.

This section is generally organized with the final paragraph

describing any recognized threats there may be to this species.

This is not restricted to ranching or grazing issues, and is

intended to describe all possible threats that may be an issue

with this species. For many species, some of these issues may

be more important than grazing or range management effects,

and readers may question why they are not discussed more

fully. Users are reminded that the emphasis of this project is on

grazing effects, and the listing here of any additional threats is

to provide a complete record of the various issues of concern

for a particular species.

Breeding Bird Survey data: For all bird species, statistical

information is reported from the North American Breeding

Bird Survey (BBS), conducted by the U.S. Geological Survey

and U.S. Fish and Wildlife Service. Data from these surveys,

conducted once a year by volunteers along 25-mile-long routes

distributed throughout each State in the United States, has been

collected annually since 1966. The USGS makes all of the data

available via the Breeding Bird Survey Web site (www.mbrpwrc.usgs.gov/bbs/bbs.html), which also provides the means

to conduct analyses of trends for individual species (Sauer and

others 2001).

We conducted analyses using data from 1966 through 2000

for each species. Analyses were done for Arizona only, New

Mexico only, and surveywide (includes all routes that detected

this species). Following BBS convention, trends were considered statistically significant only if the P-value was 0.10 or

lower. For significant trends the data are reported as follows:

(trend = +/- percent per year, P-value). However, even significant trends may be misleading and/or erroneous under certain

circumstances where the number of routes or the relative

abundance (number of birds detected per route) is low. Using

BBS guidelines, the number of routes and the relative abundance (birds/route) are also reported with significant P-values

when the number of routes is less than 14, or the relative

abundance is less than 1.0. If there are no significant trends

indicated for an area (that is, P > 0.10), then only the number

of routes and relative abundance are reported.

Example 1: “Breeding Bird Survey data from 1966-2000

indicate no significant trends in Arizona (routes = 6, birds/

route = 0.63) or New Mexico (routes = 6, birds/route = 0.63),

but a significant positive trend surveywide (trend = 1.2 percent/year, P = 0.02) (Sauer and others 2001).”

Example 2: “Breeding Bird Survey data from 1966-2000

indicate a significant negative trend in Arizona (trend = –1.4

percent/year, P = 0.015, routes = 12, birds/route = 0.7), but

significant positive trends in New Mexico (trend = 3.5 percent/

year, P = 0.012, routes = 7, birds/route = 0.6), and surveywide

(trend = 4.1 percent/year, P < 0.01) (Sauer and others 2001).”

Distribution (Narrative)—Describes the geographic range

and distribution of the species, both globally and within the

Southwest, generally in the following format:

Paragraph 1 describes the global distribution of the species,

including summer and wintering ranges for migratory species.

Paragraph 2 describes the distribution of the species in

Arizona, often using descriptions by county or by important

mapped features (mountain ranges, rivers, cities, and so forth),

and also may include comments on elevational and/or seasonal

distribution.

Paragraph 3 details the distribution of the species in New

Mexico in the same manner.

Key Distribution/Abundance/Management Areas: Stage II

panelists were asked to identify any key areas for this species

within Arizona and/or New Mexico. Such areas could be

specific geographic localities within the State, the locations of

important populations or population centers, the distribution of

specific habitat or vegetation types, or any other area or locality

that is of special importance to the species.

The areas identified in this addendum generally reflect the

opinion of the panelists but may also be supported by scientific

or government publications. General responses can include

“anywhere found” (indicating that all areas where the species

occurs should be considered especially significant) and “none

identified” (indicating that, within the species’ range in Arizona and New Mexico, no known area is particularly important

relative to the others).

The areas identified here will also be important when interpreting the panel’s response to the question regarding

prioritization of the species when selecting a grazing strategy

(see under “Grazing Effects” below).

Breeding (Narrative)—This section includes information

on the breeding biology of the species, emphasizing seasonality and timing of key events in the reproductive cycle. Focus

was put on information pertinent to land and range management (such as onset of reproduction, nesting seasons of birds,

gestation periods, age at weaning or fledging, and so forth).

Some discussion of nesting habitat or vegetation usage may be

included here, but these items are chiefly found in the habitat

section.

Habitat (Narrative)—Discusses information on the species’ habitat, including vegetative community types, individual plant species that are utilized or are characteristic of

habitat, structural elements of vegetation, topographic or other

landscape features, types of water resources utilized, elevational

distribution, home-range sizes, and various other habitat characteristics.

Generally, the species’ habitat needs throughout its range

are described, followed by more specific descriptions from

Arizona and New Mexico. Migratory birds may have separate

discussions for breeding habitats and wintering habitats; other

species may also have specialized seasonal or behavioral

habitat needs that require discussion of different habitat types.

For many species, their habitat characteristics have chiefly

been described outside of the Southwest and therefore must be
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 15

extrapolated to Southwestern biomes and ecosystems. Literature based outside of the Southwest is usually identified as

such, and caution is often advised in making extrapolations to

the Southwest due to differences in climate, topography,

landscapes, and the different plant communities and species

that may make up the species’ habitat in this region.

Landscape-Scale Habitat Requirements: The Stage II panel

was asked to provide specific information on the landscapelevel needs of each species. These are important concepts in the

fields of landscape ecology and conservation biology, but

unfortunately for most species little research has been conducted regarding these issues. The panelists often chose to

advise that more research is necessary to evaluate these requirements.

Panelists were asked to evaluate the following landscapelevel issues:

• Edge Requirements/Effects: refers to the species’ association with habitat “edges” or transition zones between

one habitat type and another. The classic example occurs

with birds at the edge of forests transitioning into open

meadows or grasslands. Some species are “edge-specialists,” whereas other species, adapted to deep-forest conditions, are negatively affected when in proximity to edge

or by increases in the amount of edge in a forest plot

(Murcia 1995).

• Connectivity Between Habitat Patches: considers whether

a species requires connectivity between habitat patches

(or habitat “corridors”) in order to disperse among separated areas. Usually not an issue with birds, the lack of

connective corridors can impact ground-dwelling animals and can create habitat “islands,” effectively isolating populations from each other.

• Habitat Area: considers the minimum habitat patch size

required by the species. For example, this can be addressed as the minimum habitat patch to support a nesting

pair of birds, or minimum area to support the home range

of a large mammal.

• Distance Between Patches: considers the maximum distance tolerated between habitat patches not connected by

habitat corridors. This maximum distance can vary depending on whether the intervening habitat is unsuitable

or simply marginal.

Part of Life Cycle (Menu)—Lists parts of the species’ life

cycle that occurs in Arizona and/or New Mexico.

• Breeding

• Hibernation/estivation

• Migration

• Wintering

Season of Use (Narrative)—Discusses any aspect of the

species’ life cycle that is seasonal in nature. This includes

descriptions of periods of breeding, migration, hibernation,

overwintering, or any other activity that occurs within specific

time frames during the course of a year.

Season of Use (Menu)—Lists the 12 months of the year

individually, with selections indicating all months when the

species may occur in either Arizona or New Mexico.

Specific Habitat Associations (Menu)—The 27 vegetation

classifications described in Milchunas (in press). For the

selections “Developed lands” and “Other,” the panel comments box is used to define these categories for the species.

Important Habitat Functions for This Species (Menu)—

Provides a list of important functions that the various habitat

elements serve for this species.

• Berry production—provides fruit as a food resource during part or all of the year.

• Escape cover—opportunistic cover from predators that

can be used quickly when required.

• Forage production—provides grass or leaves as a food

resource during part or all of the year.

• Hiding cover—any cover to conceal the species from

conspecific individuals or individuals of other species;

includes but is not limited to cover from predators or

cover to conceal a predator from potential prey.

• Insect production—supports insects as a food resource

during part or all of the year.

• Perches for hunting—typically, a viewing platform or

perch used by a predatory species (for example, shrubs or

trees used by hawks in grasslands).

• Perches not for hunting—used for other important activities that require perching (for example, territorial singing

in birds, mating displays, and so forth)

• Prey production—supports noninsect animals as a food

resource during part or all of the year.

• Reproductive cover—habitat components provide important shelter or concealment for reproductive activities,

for example protection or concealment of nests, eggs,

young, and so forth.

• Seed production—provides grains or seeds as food resources during part or all of the year.

• Shade/thermal cover—provides shelter from extreme heat

or sunshine in summer, or cover that prevents radiative

heat loss in winter.

• Water availability—selected when a body or source of water

is required or is an important feature of the species’ habitat

(not selected for general drinking water availability).

Important Structural Features of Habitat (Menu)—This

section consists of a series of menus intended to create a

detailed characterization of the structural features of the vegetative component of the species’ habitat. The lists are divided

into three general divisions (height, density, and distribution),

with each division covering trees, shrubs, and herbaceous

vegetation (forbs and grasses). Herbaceous vegetation selections that indicate “residual” refer to the standing dead vegetation after the growing season.

Within each menu, selections are based on a range of sizes for

each parameter. Each selection indicates that the species requires vegetation specifically within that size range, regardless
16 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

of what other sizes are present. Multiple selections of several of

these options indicate that the species can utilize all size classes

separately. “Variable” should be interpreted to mean that the

species requires a habitat structure with varying sizes all present

simultaneously. “Not important” indicates that the parameter

can be of any dimension; it does not automatically mean that the

feature should be absent (for example, tree canopy of “not

important” does not necessarily mean that the ideal habitat has

no trees, it simply means that the canopy is not an important

feature). As in all cases, panelists were able to use the comment

boxes to modify or clarify the definition as they understood them

while making selections.

It should be noted that for many if not most species, the

majority of these characteristics will have never been measured and may be completely unknown, even through the

panelists’ experience in the field. Readers should recognize

that these gaps in knowledge represent needs and opportunities

for additional research to further our understanding of these

species’ habitat requirements and to improve management

capabilities.

• Vegetation height:

o Trees/saguaros: (>10 m, 5-10 m, <5 m, mixed size

trees, not important, unknown, variable).

o Shrub layer: (>2 m, 0.5-2.0 m, <0.5 m, not important,

unknown, variable).

o Forb layer: (residual >1.0 m, 0.5-1.0 m, 0.25-0.5 m, 0.1-

0.25 m, <0.1 m, not important, unknown, variable).

o Grass layer: (residual >1.0 m, 0.5-1.0 m, 0.25-0.5 m,

0.1-0.25 m, <0.1 m, not important, unknown, variable).

• Vegetation density:

o Tree/saguaro canopy: (>60 percent, 40-59 percent, 1-39

percent, 0 percent, not important, unknown, variable).

o Shrub layer: (dense understory, intermediate understory, sparse understory, shrubs absent, not important,

unknown, variable).

o Herbaceous (forbs/grasses) layer: (dense cover, intermediate cover, sparse cover, bare ground, not important, unknown, variable).

• Vegetation distribution:

o Trees/saguaros: (Scattered, Clumps, Even, Not important, Unknown, Variable).

o Shrubs: (Scattered, Clumps, Even, Not important, Unknown, Variable).

o Forbs/Grasses: (Clumps, Even, Not important, Unknown, Variable).

• Tree age: the optimal age of the trees that the species

prefers. Although based in forestry terminology that

implies even-aged stands, it should be recognized that

natural environments are usually a mix of tree ages, and

that this section simply highlights any characteristic preferences of the species.

• Elevation: Three categories are provided to characterize

a species in a general elevational association: “high,”

“low,” or “all.” A dividing line of 7,000 feet is used that

conforms generally to the start of the ponderosa pine

forests in the Southwest.

Other Important Habitat Features (Menu)—This section

contains five general categories of nonvegetation habitat features. Most of the selections are self-explanatory, but a few are

defined more specifically below. (In all cases, “Variable”

indicates that the species uses a wide variety of the listed

selections and cannot be characterized by just one or a few of

the listed items).

• Body of water: Many species are associated with specific

bodies of water but often are attracted not to the water

itself but rather to the vegetation that grows in association

with it (for example, many riparian or wetland birds);

these cases will generally be noted in the comments box.

o Acequias: small irrigation channels.

o Livestock tanks: can refer to either metal tanks or

earthen berm stock tanks; the latter can often support

shoreline vegetation.

o Surface water: Surface characteristics of standing water,

ponds, or lakes.

o Tinajas:natural depressions, usually in rock substrates,

that act as water catchments after rains.

• Soil substrate/ground features: Detailed attributes of soil

and other ground substrates as well as groundcoverings

that are important habitat components. Besides soil characteristics, the list also contains “crevices” and “burrows”

that can be important for species that utilize these features

but do not excavate them on their own.

• Topography: Physical features of the landscape that are

important to the species. Selections made by the panelists

typically convey the features that best characterize the

species’ habitat, although it may actually be found in

many of the other listed topographical features.

• Tree-related features: This list contains several features

associated with trees that are not related to the vegetative

structure or growth of the tree.

o Logs: downed tree trunks; can be solid or hollow but

typically will be in some state of decay.

o Snags:standing dead trees, often utilized as a substrate

for cavities by woodpeckers. For some small mammals, this term is also used to refer to the base of a

standing dead tree (or stump) at ground level.

• Human structures: Human-made features used by the

species. The items listed here are the most common, but

additional ones may be described in the comments box.

Diet (Narrative)—The emphasis here is on the major items

that make up the diet of the species, rather than information on

food-gathering or hunting techniques or foraging ecology.

Listing or discussion of seldom-consumed diet items was

avoided.

Diet Items (Menu)—Lists relatively specific categories of

possible diet items. Again, selection of these items, as in the

text narrative above, emphasizes the characteristic diet items

and avoids listing items reported as rare or unique consumption

events.

Grazing Effects (Narrative)—The discussion of grazing

effects includes information from the scientific literature,
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 17

combined with statements of inference, observation, or opinion as provided by both the Stage I and Stage II grazing panels.

It is necessarily focused on negative impacts, given that the

objective is to create awareness of potential harm to a species

and to provide the information necessary to take steps to

mitigate any harmful effects. However, in addition, any positive effects are also included when reported in the literature or

considered to be likely possibilities by the panel.

Users should read this section with the understanding that

the objective of this narrative is to discuss potential impacts on

a species by grazing or range management practices, and the

conditions under which these impacts may occur. Whether or

not these actually occur will depend on local conditions and

situations, as well as the subsequent actions of managers to

mitigate or avoid these impacts.

Limiting habitat component relative to grazing: The Stage II

panel was asked to identify the key habitat components that

both (a) limit the presence and/or persistence of the species and

(b) are impacted by domestic or native ungulate grazing and/

or range management practices. These should be considered

the most important components of the ones that could be

potentially impacted.

Panel Assessment: Is this species a priority for selecting

a grazing strategy?—This set of questions for the Stage II

panel recognizes that the habitat requirements and the associated grazing strategies for different species will often conflict

among two or more species within this database. Therefore, the

panel was asked to provide guidance for prioritizing among

several species that may be found within a single area and have

conflicting habitat management requirements.

Question 1 (“Throughout the species’ distribution in New

Mexico and Arizona?”) asks the panel whether this species is

a priority wherever it may be found throughout the two-State

area. “Yes” is selected for the highest priority species, indicating that they should be given the greatest consideration no

matter where they occur. Species receiving this designation are

generally the most likely to be negatively impacted, or are

considered endangered or rare.

Question 2 (“In key management areas?”) provides an

opportunity for the panel to selectively prioritize a species,

based on its key distribution/abundance/management areas

(see above under “Distribution”). When answered “Yes,” with

“No” for Question 1, these species are not considered to be

important enough to be a priority anywhere they occur, but

should be considered a priority within its specific key areas.

Some general guidelines:

• Selecting “Yes” to Question 1 automatically results in a

“Yes” for Question 2.

• If “Yes” is indicated for Question 2, then either a corresponding “key area” has been described earlier under

“Distribution,” or the key area is defined as “anywhere

found.”

• If “None identified” is described under Key Areas, then

Question 2 should not be answered “Yes.”

• Specifying one or more localities under “Key Areas” does

not automatically mean that the species is to be considered a priority in these areas under Question 2.

• Any selection of “Unknown” indicates that it may be a

priority species, but not enough information is available

to make that determination.

Possible Grazing Impact Mechanisms (Menu)—This

includes:

• Alteration of soil structure—includes erosion, compaction, and other impacts to soils that can affect plant

growth, plant community composition, streambank structure, or even the ability of the species to create dens or

burrows.

• Alteration of water regimes—includes both changes induced by the presence of cattle (lowering of water tables,

drying of springs, and so forth) as well as changes

resulting from range management activities (for example,

groundwater pumping, water diversions, conversion of

springs to watering tanks, and so forth.).

• Altered fire regime—includes both changes induced by

the presence of cattle (for example, removal of grasses

that carry low-intensity surface fires) as well as changes

resulting from management activities (fire suppression,

introduction of nonnative grasses that increase fuel loads,

and so forth.).

• Altered vegetation composition—changes to the species

composition of plant communities, including removal of

dominant species, introduction of nonnative plants, and

facilitating the encroachment or invasion of plant species

from outside the local community (for example, shrub

encroachment into grasslands).

• Altered vegetation structure—changes to the height, density, or distribution of plant species, by either ungulate

grazing or range management activities.

• Change in prey/food availability—elimination or decline

in the abundance of important prey species, or the availability of important food items such as seeds.

• Change in water quality—increases in silt or sedimentation, or the introduction of waste material, fertilizers, or

other pollutants that change the chemical balance of

natural water sources.

• Competition for forage—the species in the account and

grazing and/or browsing ungulates rely on the same plant

species and/or plant components for forage.

• Cowbird parasitism—the species is subject to brood

parasitism by one or both of two cowbird species in the

Southwest: the brown-headed cowbird and the bronzed

cowbird. Brood parasitism occurs when one species of

bird (parasite) lays its eggs in the nest of a different bird

species (host). The host parent then expends energy and

food feeding and rearing the parasitic chick, often at the

expense of its own reproductive output. Cowbirds are

known to parasitize a variety of host species in the

Southwest. In addition, they tend to congregate near herds

of cattle; therefore, the presence of cattle may increase the
18 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

likelihood of host exposure to cowbirds (Goguen and

Matthews 1999; also see discussion below under “Summary of Ecological Interactions with Wildlife”).

• Habitat fragmentation—alteration of the distribution of

vegetation such that the species’ habitat is broken into

smaller, discontinuous fragments. This is especially consequential to species that require either large patches of

habitat, new habitat areas to disperse into, or low amounts

of edge habitat.

• Increased predation—refers to changes to a species’

habitat or environment that increase the likelihood of

predation on the species. These changes can include

reduction or removal of sources of cover, or changes to

habitat structure that allow greater access by predators.

• Intentional killing—mortality as a direct result of human

hunting, trapping, poisoning, shooting, and so forth,

conducted for the benefit of livestock or range conditions.

• Killing burrowing rodents—the specific killing of rodents that create burrows or dens (and thus may contribute

to habitat for other species), for example, prairie-dogs and

kangaroo rats. Species with this selection may also be

important prey items for predators.

• Other biotic factors—includes any biological phenomena

not found elsewhere on this list. If selected, the specific

definition should be included in the comments box.

• Parasites or pathogens—the introduction, spread, or facilitation of any parasitic or pathogenic organisms to the

species covered in the account.

• Population genetic structure loss—the elimination of

certain populations of a species may have larger consequences if the population contains important or unique

genetic elements of the species, is a source of genetic

variability for the species, or is otherwise important in the

population genetic structure of the species.

• Range improvements—includes any modification, alteration or addition to the range and/or range landscape as a

result of activities in support of livestock or range operations. Examples include construction of stock tanks,

roads, or fences; clearing of shrubs to create pure grasslands and other vegetation alterations; seeding of nonnative grasses; and so forth. This selection is accompanied

by additional definitions in the comments box.

• Trampling, scratching—the species experiences direct

impacts from livestock or native ungulates through these

mechanisms.

Fire Regime Requirements (Narrative)—Each Stage II

panel was requested to evaluate whether the species’ habitat

required a natural fire regime to maintain the specific requirements of that species. If the panel determined that a fire regime

was important, they then made selections from the three menus

for fire frequency, intensity, and timing (otherwise, “Not

important” was selected).

The panelists were chosen for their knowledge as wildlife

experts, so their knowledge of fire ecology varied considerably; often they chose to select “unknown” to emphasize that

fire may be important but it was beyond their capability to

evaluate. In some cases, fire was known to be important, but the

specifics of frequency, intensity, and timing were not known.

The panelists also recognized that some habitats do not tolerate

any level of fire frequency or intensity, and thus could be said

to have a regime of “no fires” that was critically important for

the species.

Fire Regime Requirements (Menu)—This includes:

• Frequency - High (1- to 10-year interval), Intermediate

(11- to 100-year interval), Low (>100-year interval),

None (the absence of fire is considered important for this

habitat), Unknown, Not important.

• Intensity - High (stand replacing), Medium (affects shrubs),

Low (surface fire), None (the absence of fire is considered

important to this habitat), Unknown, Not important.

• Timing - Spring, Summer, Fall, Winter, Never (the absence of fire is considered important to this habitat),

Unknown, Not important.

References—This section lists all literature, reports, publications, or personal communications cited in the individual

species account.

Authors/Panelists—These include:

• Draft: author(s) responsible for researching and writing

the draft species account presented to the Stage II panel.

• GP 1999: participants on the Stage I panel.

• GP 2000 (or other year): participants on the Stage II panel.

• Revision: author(s) responsible for rewriting the draft to

incorporate the Stage II panelists’ comments, changes,

new information, or new references.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 19

Stage I Results

The Stage I process resulted in a list of 323 species, or

approximately 37 percent of the 866 total number of species

considered (table 1). By taxonomic group, 19 percent of the

herpetofauna were selected, 39 percent of the grassland/desert

scrub bird species, 48 percent of woodland birds, 35 percent of

riparian/wetland birds, and 49 percent of the mammals.

Several species were considered in the Stage I process as

multiple subspecies. Table 1 reports both the number of

species considered as well as the total number of taxa, including subspecies that were considered individually. Larger numbers of mammalian taxa were considered as subspecies, both

because the ecology and natural history of many small mammals more readily leads to the evolution of recognizable

subspecies, and because the field of mammalogy tends to use

subspecific designations more readily than do other fields of

vertebrate zoology (it should also be noted, however, that the

American Ornithologists’ Union endorses the biological reality and practical utility of subspecies; see AOU 1998, p. xii).

Stage II Results

Rejections and Additions—The panelists in Stage II consistently removed more species than they added across all

taxonomic groups, averaging 2.4 species removed for every

one added (table 1). In all, the number of species from the Stage

I process was reduced by approximately 13 percent. The

fewest changes based on percent loss of species were in the

herpetofauna (net loss of one species, or approximately 3

percent) and the mammals (net loss of five species, or 5

percent). The largest changes were in the birds: grassland/

desert scrub species were reduced by 10 species (20 percent),

riparian/wetland birds by 16 species (18 percent), and the

woodland species by 9 species (15 percent). Removal of

grassland/desert scrub birds probably reflects the varying

responses of many of these species depending on grazing

intensity, habitats, climate, and short-term versus long-term

effects. Several riparian bird species were removed that utilize

Southwestern riparian habitat corridors for migration, but do

not regularly winter or breed here. Despite the importance of

this habitat during migration, the impact on these species from

grazing was considered to be minimal (see species accounts as

well as appendix D for details). The final tally represents

approximately one-third of the total number of taxa reviewed

in Stage I, with mammals having the greatest rate of inclusion

(46 percent) and herpetofauna the smallest (18 percent). When

the three bird categories are combined, herpetofauna make up

approximately 10 percent of the final list of 283 species, birds

57 percent, and mammals 33 percent.

Results: Species List Generated by the Panel Process _________________

Many of the species removed in the Stage II process may still

warrant consideration by the reader in order to understand why

these species were rejected, and the circumstances under

which these taxa could be negatively impacted (if at all) by

grazing or range management. Therefore, a short account

discussing distribution, habitat, and issues surrounding grazing effects is provided for these species in appendix D.

Final List of Species and Subspecies Accounts—Using

the guidelines for breaking species into separate accounts by

subspecies, the panelists directed that 13 species be separated

into multiple subspecific accounts. Few of these were among

birds (two species divided into five accounts), with most

occurring for herpetofauna (five species divided into 13 accounts) and mammals (six species divided into 17 accounts).

Most of the mammal subspecific accounts are due to splitting

two species (eastern cottontail and thirteen-lined ground squirrel) into four separate subspecies accounts each. The final

number of individual accounts in the database is 305, the

majority being birds (half of those being riparian/wetland

species), approximately one-third mammals, and one-eighth

herpetofauna (table 2).

Designation of “Priority Species”—Among the three categories of prioritization—priorities in key areas only, priorities in all areas, and unknown or not a priority)—proportions

were generally similar across the five groups (fig. 1). Of all the

accounts in the database, almost three-quarters were given

some type of priority designation, with 79 (26 percent) listed

as nonpriority species or unknown. Approximately half (159,

or 52 percent, of the 305 taxa) were ranked as priorities

throughout their respective ranges, while almost one-quarter

(67 taxa, or 22 percent) were considered priorities only within

key areas. Notable departures from these averages include the

mammals, with 66 percent of taxa receiving priority designations in all areas, and woodland birds, with a substantially

greater proportion of taxa being nonpriority (47 percent) and a

smaller proportion designated as priority species throughout

their range (28 percent). Herpetofauna had a slightly greater

proportion of nonpriority species (34 percent) than the overall

average, and grassland/desert-scrub birds had slightly more

categorized as priorities in key areas only (28 percent). Analyzed by raw numbers, mammals have the most taxa with some

type of priority designation (87), followed by riparian birds

(55); species of grassland/desertscrub birds (31), woodland

birds (28), and herpetofauna (25) have similar numbers of

priority taxa.
20 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Figure 1—Comparison of the numbers of species assigned to different prioritization categories in

herpetofauna, grassland/desert scrub (GRDS) birds, woodland (WDLD) birds, riparian (RIP) birds, and

mammals. Categories include priority species in designated key areas only, priority species in their entire

range in the Southwest, and those designated as “unknown” or otherwise nonpriority species.

PRIORITY SPECIES

0

20

40

60

80

100

120

HERPS

BIRDS (GRDS)

BIRDS (WDLD)

BIRDS(RIP)

MAMMALS

PRIORITY, ALL AREAS

PRIORITY, KEY AREAS

ONLY

UNKNOWN OR NOT

PRIORITY
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 21

Interpreting the “Grazing Effects” Section

Within each account, grazing impacts are discussed in the

“Grazing Effects” narrative, which includes information based

on the scientific literature as well as the knowledge, experience, and assessment of the panelists. Although the focus of

this study is on Arizona and New Mexico, some references

may be included that involve studies from outside these two

States. Readers should use caution in extrapolating information from outside the Southwest to this region. The climatic and

ecological attributes of these “outside” studies (for example,

precipitation, soils, vegetation communities and structure,

vertebrate communities, evolutionary grazing histories, and so

forth.) are often very different. Such studies often suggest

management strategies that are inappropriate for the vegetation and wildlife communities of the Southwest. Nevertheless,

in cases where the ecosystems are quite similar (for example,

ponderosa pine forests, high-altitude willow-riparian), or when

there is little information from the Southwest, these studies can

prove useful when interpreted carefully.

Readers will also note that the discussion of grazing effects

in the accounts can include both short-term and long-term

effects. Short-term effects tend to be relatively direct, whereas

long-term effects often involve more complex ecological processes and are often indirect. For example, grazing that reduces

grass heights or groundcover is considered a short-term effect,

occurring within a single grazing season. Long-term ecological effects include such processes as grazing-induced shrub

encroachment into desert grasslands and grazing-related fire

suppression in ponderosa pine forests that leads to dense

thickets of small trees (see further discussion below and in

Milchunas, in press). Such effects typically are not recognizable over one or even a few seasons but rather manifest

themselves over a period of many years.

In all cases, it is important to recognize that the goal of this

process was to identify potential impacts on each species. This

is not an attempt to document that these effects are occurring

today, or that any of these species are currently in decline

because of grazing or range management. Neither should they

be interpreted to imply that these effects are inevitable under all

grazing conditions or management programs. Rather, the “Grazing Effects” sections are intended to present information on

potential impacts that can occur and the mechanisms by which

these may be realized. In this way, the database provides

information for land managers interested in mitigating possible adverse effects on the wildlife species identified here.

Summary of Panel Findings on Ecological

Interactions with Wildlife

The following sections comprise a synopsis of the major

findings of the panels for terrestrial wildlife species in the

Southwest. These sections are intended to provide a summary

Results: Panel Findings on Grazing/Wildlife Interactions________________

of the information presented in the individual species accounts

and not act as a substitute. The discussion here is intentionally

generalized and does not cover every species in the database,

nor does it contain all effects identified for a particular species.

Readers should consult the accounts for more detailed and

complete presentations of the panelists’ assessments of individual species.

Readers will recognize that while several species are affected by similar impacts, there are also situations where

different species have conflicting habitat and management

needs. Part of this is due to the fact that differences in geographical distribution are not taken into account here; however, there are likely to be species with overlapping distributions and habitat utilization that experience conflicting grazing

effects. In these cases, land managers will need to develop a

system to prioritize among species; the priority designations

provided by the panelists can facilitate this effort. However,

managers are also encouraged to use the more detailed ecological information provided in the individual accounts in order to

develop a more comprehensive grazing strategy for their area.

Herpetofauna - Riparian/Aquatic Habitats—A variety of

factors associated with ungulate grazing and range management interact with the ecological requirements of reptiles and

amphibians, but probably the most important concerns impacts

to aquatic habitats and associated riparian and shoreline vegetation. Given the arid nature of the Southwest, these habitats

are both rare and highly vulnerable, yet many species depend

on them in order to persist in an otherwise hostile environment.

Amphibians are considered sensitive indicators of environmental quality not only because they require the presence of

water but also because most species are capable of conducting

gas exchange and absorbing environmental chemicals across

the skin. This increases their environmental sensitivity and

makes them more vulnerable to pollutants and reduced water

quality. Many reptiles listed in this database are also dependent

on riparian or aquatic resources, and for that reason are more

vulnerable than other reptile species in the Southwest.

High-quality water sources, along with emergent riparian

and aquatic vegetation, are important not only for the amphibians listed in the database (tiger salamanders, leopard frogs)

but also for turtles (yellow mud turtle, Sonoran mud turtle,

ornate box turtle) and species of snake from the genus

Thamnophis(narrowhead garter snake, Mexican garter snake,

western ribbon snake). Impacts to riparian or aquatic habitats

can occur when high densities of ungulates are attracted to

natural water sources. This can result in the degradation or

elimination of dense herbaceous vegetation, increased erosion

of banks and shorelines leading to increased siltation, as well

as potentially increasing pollutants from animal wastes. Salamanders and frogs would be most sensitive to these effects, but

they will also be a concern for reptile species that are dependent

on these habitats. The disruption of natural water regimes,
22 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

specifically in the playa lakes region, is likely the main

potential impact on the yellow mud turtles (GP 2000a). In

Arizona, increased runoff from denuded grasslands and water

diversion from valley floors into deepened reservoirs may

have contributed to the reduction of ephemeral wetlands in

flooded valley floors (GP 2000a). All Thamnophis snakes

require dense shoreline vegetation, but the narrowhead garter

snake has a greater reliance on aquatic habitat than the other

species of Thamnophis. In addition to dense shoreline vegetation, other habitat requirements include clear water, undercut

banks, and abundant fish prey species, all of which could be

degraded by ungulate densities that increase erosion and sedimentation, and decrease water quality. The giant spotted

whiptail requires dense riparian vegetation and groundcover,

whereas the leopard lizard appears not to be sensitive to

grazing intensities but nevertheless requires a minimum amount

of vegetative cover in its riparian habitats. The yellowbelly

racer, while found in a variety of different vegetation communities, does have a strong association with water sources in arid

localities. It is strongly associated with riparian areas where it

still occurs in New Mexico, and loss of the most lush grassland

and riparian bottoms may have led to the extinction of this

species from most or all of its Arizona range (GP 1999a,

2000a).

The development of surface water sources (earthen stock

tanks, windmills, and spring developments) can provide suitable aquatic habitat for some species, resulting in increased

habitat and water permanence. However, it can also negatively

impact natural habitats as well as promote concentrations of

livestock and other ungulates. The creation of stock tank

habitat has the potential to increase a species’ overall abundance, number of populations, and probably distribution, with

likely consequences for population genetic structure and integrity. For example, many artificial surface water sites are known

to support large populations of the Sonoran mud turtle (GP

2000a). For many species, however, these tanks can create a

population “sink,” a locality where individuals die off at a

faster rate than they are recruited. Stock tanks can often be

introduced with bullfrogs, crawfish, and exotic fishes that are

highly predatory on adult frogs and salamanders as well as

tadpoles (GP 1999a, 2000a). Bullfrogs also prey heavily on

garter snakes. For the Mexican garter snake, introduced species of predatory bullfrogs and fish seem to be the most

important reason for population declines. Converting cienega

and stream habitats into ponds often favors introduced predators. However, in areas where introduced predator problems

are not reversible, grazing management practices may not have

a great affect on this species (GP 2000a).

Herpetofauna - Grassland/Shrub Habitats—Several species require a well-developed, healthy grass layer, in some

cases simply as a component of a variety of vegetative community types. Maintenance of grasslands or the herbaceous component of other habitats likely provides support for an insect

prey base as well as cover for lizard or snake species (GP

2000a). The Arizona skink, although found in a variety of

vegetation communities, requires areas with tall herbaceous

vegetation and lower population densities have been documented in heavily versus lightly grazed sites (Jones 1981). The

short-horned lizard has been documented to occur in lower

abundance in heavily versus lightly grazed areas (Jones 1981),

but the causal mechanism has not been identified. The difference may be attributable to a reduction in food sources (such

as seed-eating ants and other insects) due to depletion of

herbaceous cover (GP 2000a). In addition, conversion of

sagebrush habitats to invasive nonnative grasses has been

reported to be detrimental to this species (Reynolds 1979).

Grazing and range management practices also interact with

the natural processes balancing the distribution of pure grasslands with that of scrublands in the Southwest. Fire and

drought once maintained mosaics of grass and grass/shrub

habitats in the American Southwest lowlands. In recent times,

livestock grazing reduced fire frequency by removing herbaceous fuel loads, thus exacerbating the effects of drought and

generally increasing woody species at the expense of grasslands (Bock and Bock 1998 and references cited therein).

However, fire and other forms of shrub removal can also be

used as a range management tool to remove woody vegetation

and create a landscape dominated by grasses and other herbaceous vegetation.

Several species of lizards and snakes respond differently to

these broad landscape effects. All five subspecies of the little

striped whiptail prefer well-developed grassland habitat, and

any effects that lead to shrub invasion/conversion noticeably

and quickly increase populations of competing whiptails,

primarily the desert grassland whiptail (GP 1999a, 2000a). The

milk snake occurs in a variety of habitats, but is reliant on

sufficient herbaceous vegetation; in Arizona, it is found only in

healthy grasslands. Conversion of grasslands to scrublands,

and other grassland degradation due to improper grazing, may

lead to declines or extinctions in some areas (GP 2000a).

Among the rattlesnakes, two (the Mojave rattlesnake and

desert massasauga) are grassland specialists that respond negatively to degradation of pure grasslands by shrub encroachment. The relative abundance of the Mojave rattlesnake (a

grassland species) has decreased, and the western diamondback rattlesnake (shrub and mixed shrub/grassland species)

has increased over a 30-year period in an area of southeastern

Arizona and southwestern New Mexico (Mendelson and

Jennings 1992). These changes in relative abundance are

associated with a decrease in desert grassland and an increase

in desert scrub in this area (Mendelson and Jennings 1992). In

Missouri, the desert massasauga has been shown to increase in

prairie grasslands when grazing pressures are removed (Siegel

1986). In the Southwest, any conversion of grasslands to

scrublands would definitely have a severe negative effect on

most populations of this species due to a loss of protective

cover (which leads to more predation) (GP 2000a).

Other species, such as the western diamondback rattlesnake,

may respond positively to grazing-induced shrub encroachment into grasslands. Both the Clark’s spiny lizard and eastern

fence lizard may benefit from an increase of woodland and

spread of woody vegetation into pure grassland. Indeed, Jones
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 23

(1981) found the eastern fence lizard to be more abundant in

heavily grazed chaparral and grassland. In some cases grazing

may still be detrimental: the reduction of riparian vegetation

and negative impacts on the recruitment of large deciduous

riparian trees could negatively affect Clark’s spiny lizard. In

yucca grasslands, grazing that impacts yucca and yucca stalks

can remove important cover components of the eastern fence

lizard’s habitat (GP 1999a, 2000a).

The sand dune lizard poses a unique situation in that grazing

itself does not negatively affect the species, but rather, the

chemical treatment of shinnery oak to promote habitat conversion to grassland has had serious negative impacts (GP 2000a).

Several authors (Gorum and others 1995; Snell and Landwer

1992; Snell and others 1993; Snell and others 1994) agree that

while grazing does not appear to negatively impact this lizard,

the range improvement program of clearing shinnery oak

causes drastic reductions in sand dune lizard abundance. The

desert massasauga (discussed earlier) has a specialized shinnery oak population in New Mexico, which would likely suffer

from the chemical treatment of shinnery oak in a similar

manner as the sand dune lizard (GP 2000a).

Herpetofauna - Fire and Grazing Interactions—Over

long periods of time, particularly in drier forest types such as

ponderosa pine, improper grazing has the potential to contribute to buildups of woody vegetation and increase the risk of

catastrophic fire (see discussions of fire and grazing in

Milchunas, in press). The two subspecies of the ridgenose

rattlesnake are noteworthy here because each occurs in small

isolated populations occupying wooded canyons and are of

conservation concern (the New Mexico ridgenose rattlesnake

is Federally listed as threatened). Habitat destruction of any

sort could negatively affect the small New Mexico population,

or the isolated population in the Whetstone Mountains of

Arizona. The major concern, however, is the loss of woodland

due to heavy fuel accumulations leading to intense wildfire.

This could lead either to direct mortality or to the loss of the

brush mouse, an important food item (GP 1999a).

Herpetofauna - Direct Mortality—The panelists recognized that rattlesnakes in general are frequent targets of eradication by many landowners in the Southwest (that is, not just

by ranchers or range managers) and considered this direct

mortality (especially den massacres) to be a significant negative factor for rattlesnakes in relationship to range management (GP 1999a, 2000a). Loss of vegetative cover and exposure on roads can increase their detectability and thus the

incidence of direct mortality.

Herpetofauna - Effects on Prey Species—As predators,

rattlesnakes require a prey population base greater than that

required to simply maintain the prey population. Several

grazing or range management effects could lead to a reduction

of prey populations (for example, elimination of vegetative

food base or cover of prey, invasion of nonnative grasses, and

so forth). These effects have the potential to reduce the abundance of prey to a level where the rattlesnake population cannot

be maintained. (See later discussions under Mammals for

further discussion of the issue of indirect effects on predators

via the food chain.)

Other Effects on Herpetofauna—Another issue associated with large concentrations of ungulates for long periods is

soil compaction. Many turtles require soil that is easily penetrated for the excavation of nesting, resting, and hibernation

sites, and deep enough to escape freezing winter temperatures

(Legler 1960 as cited in Degenhardt and others 1996). Because

of this requirement, compaction of soils by heavy ungulate use

would negatively impact the habitat. For the ornate box turtle,

the loss of prairie dog towns (due to disease or control efforts)

may have negative effects because box turtles are known to

utilize the burrows (GP 2000a).

The desert tortoise is a species of high conservation concern;

however, there is some dispute in the scientific literature as to

the nature and extent of the impacts of cattle and grazing on this

species. Reported effects include competition for forage, alteration of vegetation structure and composition, introduction

and spread of exotic vegetation, trampling of young tortoises,

and trampling of burrows. Other authors (for example,

Oldemeyer 1994) note that experimental information on the

effect of livestock grazing on tortoises is lacking and that

research has not yet examined whether forage remaining after

grazing is sufficient to meet the nutritional requirements of

tortoises.

Birds – Introduction—The effects of grazing and range

management on bird species in the Southwest are varied, but

the potential for negative impact is almost entirely related to

the alteration or elimination of required components of the

vegetative substrate. This is largely connected to requirements

for breeding and/or hiding and escape cover, but it is also

related to effects on the food supply. This includes not only the

production of seeds from grasses and forbs, but also the

productivity of the animal prey base, primarily insects but also

other animal food sources such as small mammals.

The details of these ecological requirements, and how grazing and range management may affect them, vary tremendously among the different vegetative communities of the

Southwest as well as from species to species. This discussion

of the panelists’ identification of potential effects on birds

therefore includes five broad ecological categories: grasslands, scrublands, woodlands, riparian areas, and wetlands.

Other major effects discussed are the impacts on groundnesters in all habitats, and the impact of brood parasitism by

cowbirds.

Birds - Grassland Habitats— By its nature, the grazing of

livestock reduces the height and density of available grasses;

this alteration can both degrade ecological conditions for some

species while improving them for others. Species such as the

savannah sparrow are highly sensitive to grazing, responding

negatively in almost all situations in which this has been

studied (see Saab and others 1995). However, for some grassland species, the overall effect can depend on the grassland

ecosystem in which the grazing takes place. Several species

breed in the grasslands of the Great Plains as well as those of
24 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

the Southwest. In many of these cases the same intensity of

grazing can be beneficial in the former (creating preferred

habitat conditions in the taller, denser grasses of the Great

Plains) while eliminating vegetative requirements in the Southwest (where grasses tend to be shorter and sparser). Species

such as the bobolink and dickcissel reach the periphery of their

range in the Southwest and are most abundant in the Great

Plains grasslands. Both are more sensitive to grazing pressures

in shorter grasslands, although they may respond positively to

grazing in tallgrass prairie (Bock and others 1993; Kantrud and

Kologiski 1982; Skinner 1975). Species such as the eastern

meadowlark, grasshopper sparrow, and Cassin’s sparrow may

also benefit from light to moderate grazing in parts of their

breeding range outside the Southwest, but in sparse, arid

grasslands, the required amount of grassy groundcover can

easily be eliminated (Ruth 2000; Vickery 1996). Similarly,

lark buntings are sensitive to heavy grazing in arid, short-grass

habitats, but may tolerate less intense grazing regimes (Finch

and others 1987; Giezentanner and Ryder 1969 as cited in

Shane 2000). Some birds such as the long-billed curlew prefer

low grass heights for nesting, and grazing has actually been

recommended to improve breeding habitat for this species in

some areas (Bicak and others 1982). However, grazing that

reduces grass heights to extremely low levels or increases the

area of barren ground would degrade the habitat necessary to

support breeding birds (GP 2001a).

Some species appear to rely on specific native grasses for

essential habitat. Botteri’s sparrow requires tall, dense stands

of sacaton grasses, which can be affected by grazing as well as

management practices that repeatedly burn stands of sacaton to

produce livestock forage from the new growth. Phillips (1968)

found that the most “flourishing colonies” of rufous-winged

sparrows were formerly found in meadows of tobosa, a grass

that disappears under heavy grazing pressure, and that grazing

reduces the overall grass cover required to provide suitable

habitat for this sparrow (Phillips and others 1964).

Wintering grassland birds can be affected by reductions in

grasses and forbs that provide important food resources in the

form of seeds during the winter months. Several grassland

birds (such as the Baird’s sparrow, grasshopper sparrow,

chestnut-collared longspur, savannah sparrow, vesper sparrow, and eastern meadowlark, among others) that are insectivorous during the breeding season often switch to a primarily

granivorous diet during winter months. Lark buntings in winter

feed primarily on seeds and tend to occur more frequently in

areas that have received greater summer rainfalls; thus, they

appear to prefer areas with greater herbaceous seed production

(GP 2000b). The American tree sparrow also relies heavily on

grass and forb seeds during the winter. These wintering birds

could be negatively impacted by grazing levels that reduce or

eliminate seedhead formation by grasses and forbs.

One element of habitat alteration in Southwestern grasslands that is due more to range management than ungulate

grazing of the grass per se is the introduction of exotic grass

species adapted to arid environments in order to increase the

forage available for livestock. An example is the African

lovegrasses, which have become well-established in some

areas of the Southwest, particularly the desert grasslands of

Arizona. For some bird species, the effects of these grasses can

be positive: the Botteri’s sparrow, a tall-grass specialist adapted

to the native sacaton grasses, has increased in abundance in

stands of exotic lovegrasses (GP 1999b). The invasion of some

exotic grasses may actually increase the suitability of grazed

areas for some species (such as the Baird’s sparrow) by

providing cover (C. Gordon, personal communication as cited

in Jones and Green 1998). However, other species (for example, eastern meadowlark, vesper sparrow) have been shown

to avoid pastures of introduced exotic African lovegrasses in

favor of native grasslands (Bock and Bock 1988).

The presence of a significant shrub component can also

prove detrimental to many species that are adapted to a pure

grassland ecosystem. Several studies have documented how

excessive grazing can result in the invasion of woody shrubs

into formerly pure grassland, and a gradual conversion to a

mixed or even shrub-dominated community (Milchunas, in

press). The preferential grazing of grasses over shrubs (which

alters the balance of competition for soil and water resources)

also results in fire suppression due to the removal of grasses as

a fuel and conductor of fire across the landscape (thus removing a mechanism for eliminating woody shrub growth). Such

“shrub encroachment” is thus recognized as a potential longterm effect of grazing in Southwestern grasslands (although

conditions such as extended drought or climate change can also

be contributing, as well as primary, factors in this conversion;

Milchunas, in press). Several species were identified that rely

on pure, open grassland habitats: breeding birds, such as the

burrowing owl, vesper sparrow, and Botteri’s sparrow, and

wintering birds, such as the chestnut-collared longspur,

Sprague’s pipit, and Baird’s sparrow, are considered particularly sensitive to shrub encroachment into grasslands. Grassland raptors, such as the aplomado falcon and ferruginous

hawk, may also decline in abundance when grassland converts

to scrubland, possibly through indirect effects on preferred

small mammal prey species.

The presence of prairie dog colonies in Southwestern grasslands is important for several grassland bird species, and their

eradication may negatively impact grassland raptors. Most

directly affected by prairie dog towns are burrowing owls,

which do not actually burrow themselves but rely on prairie

dog colonies for nesting burrows. In tallgrass prairie, grazing

can help create prairie dog habitat (Kantrud and Kologiski

1982), but it is not considered necessary in the sparser grasslands of the Southwest (GP 2000c). Some authors (for example, Phillips and others 1964) believe that prairie dog

eradication efforts have had a negative effect on owl populations. Prairie dogs also are important prey species for raptors

such as the ferruginous hawk and golden eagle that hunt in

open grasslands. Truett (2002) suggested that prairie dog

elimination, rather than overgrazing, contributed to the decline

of the aplomado falcon in the Southwest. None of these raptors

relies exclusively on prairie dogs, and impacts to a variety of

small mammal species could indirectly affect these birds (see

further discussion under Mammals, below).
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 25

Birds - Desert-Scrub and Shrub Habitats—A number of

bird species require a shrub component as part of their preferred habitat, ranging from scattered shrubs in grassland (for

example, as required by Cassin’s sparrows) to dense stands of

shrubs. As discussed briefly above, over the long term, livestock grazing in grasslands can contribute to the encroachment

of woody shrubs and cactus into pure grassland. Indeed, such

interactions led the Stage II panels to reject species such as the

cactus wren that benefit from these effects (see appendix D). In

shrub and desertscrub habitats, the potential for negative

consequences comes from two sources: high densities of

livestock that adversely affect shrubs and/or cacti, and management activities that chemically or mechanically clear away

shrubs and cactus in order to create grassland habitats.

Many shrub and desertscrub species also benefit from the

herbaceous component of these habitats and may respond

negatively if this is degraded as well. Several birds require

substantial grass and forb understory along with a shrub

component for building nest structures or to use as breeding

cover. Habitat requirements often include low to moderate

shrub densities and can become unsuitable if shrubs become

too dominant. Black-chinned sparrows and northern cardinals

both require the seeds produced by grasses and forbs as well as

low to moderate densities of chaparral or desert-scrub. Several

species of gallinaceous birds also fit in this category. Scaled

quail, lesser prairie-chicken and masked bobwhite all require

some cover of woody vegetation along with a healthy layer of

herbaceous vegetation. Light to moderate grazing may be

tolerated by or even beneficial for many of these species

(depending on intensity and climatic conditions, such as

drought), while heavy grazing resulting in desertification or

that promotes high shrub density could have severe negative

effects (GP 1999b).

Other species require higher densities of shrubs or desertscrub, which may be more readily reduced from optimum

densities by high stocking levels of livestock. The varied

bunting and black-tailed gnatcatcher are examples of species

that inhabit areas of high shrub density in desert scrub habitats,

particularly desert washes. The pyrrhuloxia in Arizona is a bird

of Sonoran Desert xeroriparian scrub, and the crissal and

LeConte’s thrashers also inhabit areas of desert-scrub, although LeConte’s thrasher is characteristic of more open and

arid habitats. Some of these (varied bunting, crissal thrasher,

pyrrhuloxia) appear to have a special affinity for mesquite

thickets (Cody 1999; Wolfe 1968) and may have benefited to

some degree from grazing-induced expansion of mesquite into

grasslands. In addition to shrub removal or degradation, the

presence of livestock may also impact the insect prey base by

removing available herbaceous vegetation in arid environments, or, as in the case of LeConte’s thrasher, by disturbing

the groundcover of litter that supports its arthropod prey

(Sheppard 1996).

The Sonoran desert ecosystem hosts bird species that specifically rely on the saguaro cactus for breeding structures, as

well as components of the shrub and cactus understory as part

of their habitat requirements. The Gila woodpecker and gilded

flicker are important primary cavity nesters in saguaros, excavating cavities that will later be utilized by species of secondary cavity nesters. Species that utilize abandoned woodpecker

cavities in saguaros for nesting include the American kestrel,

elf owl, cactus ferruginous pygmy-owl, western screech-owl,

ash-throated flycatcher, brown-crested flycatcher, and purple

martin (Kerpez and Smith 1990). The Harris’ hawk, in addition

to large mesquites and riparian trees, also utilizes saguaros for

nesting structures. Sonoran Desert vegetation, particularly the

long-lived and slow-growing cacti, is relatively fragile compared to vegetation in other Southwestern vegetation communities and is thus more vulnerable to heavy browsing and

trampling. As seedlings, large cacti such as saguaros are

particularly vulnerable and can be affected either by direct

trampling or by clearing of other vegetation (“nurse plants”)

required for protection from exposure to the sun. In addition,

livestock grazing in the Sonoran Desert has contributed to the

expansion of exotic grasses (for example, red brome, lovegrass),

which have in turn led to an increased probability of destructive

fires (GP 2000d). The incidence of wildfire in the Sonoran

Desert has increased in recent decades (Narog and others 1995;

Schmid and Rogers 1988). Because they are unadapted to

frequent fire, saguaros experience high mortality rates during

or after wildfire, and their numbers sharply decrease in burned

areas (Cave and Patten 1984; Wilson and others 1996); postfire

mortality among saguaros can reach 80 percent (Wilson and

others 1996). In this ecosystem, clearing desert scrub and

increasing the grass component can be detrimental to species

such as the common poorwill, which prefers more mid-canopy

perennial vegetation rather than grassy groundcover (Hardy

and others 1998).

Other species have strong affinities for specific types of

scrub vegetation. Scott’s oriole is common in yucca grasslands

and in low-elevation desert scrub or pinyon-juniper woodlands

with a yucca component; it utilizes the large stalks in order to

construct its pendant nest (Kozma and Matthews 1997). Similarly, the sage sparrow is closely associated with pure stands of

big sagebrush or stands intermingled with other desert scrub

vegetation (Martin and Carlson 1998). In each case, any range

improvement involving the clearing of the required vegetation

to create a grass monoculture would be detrimental.

The next section focuses on woodland habitats, but there are

several species that are strongly associated with dense shrub

habitats in conjunction with coniferous woodlands. The greentailed towhee is considered a breeding bird of montane habitats, but it is found almost exclusively in open areas adjacent to

woodlands or forest edge where there is a substantial shrub

component (it also breeds at lower elevations in sagebrush

shrub-steppe and other mixed-species shrub communities).

The blue-gray gnatcatcher is also a species of dense shrubs and

small trees in a variety of shrub-woodland habitats, including

Upper Sonoran oak woodland and chaparral habitats, and

habitats dominated by pinyon pine up to stands of Gambel oak

and mountain mahogany (GP 2000c; Phillips and others 1964).

Again, reduction of the shrub component through clearing or

high stocking densities could rapidly reduce the shrub densities below the suitability thresholds for these species.
26 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Birds - Woodland Habitats—In both Arizona and New

Mexico, woodland habitats vary tremendously as a function of

elevation and water availability (either annual precipitation or

ground water). Within these woodland ecosystems, the distribution of birds is often affected by the amount of canopy cover,

forest density, and the amount of understory shrubs and herbaceous vegetation. Most of the effects of ungulate grazing in

these habitats manifest themselves over long periods; for

example, intensive grazing in ponderosa pine woodland, which

contributes to the suppression of low-intensity fires (thus

ultimately affecting forest structure and catastrophic fire risks),

and browsing of deciduous tree seedlings, which affects the

long-term recruitment of large, mature trees required for nesting or food supplies. However, short-term effects can also be

recognized through the removal of understory shrubs and

herbaceous vegetation that provide food supplies through the

insect prey base, seeds, or fruits and flowers.

Similar to the earlier discussions of potential impacts to birds

in grasslands and desert scrublands, several species in woodlands are vulnerable to the reduction or elimination of herbaceous vegetation and/or understory shrubs. In their respective

habitats, birds such as the elegant trogon and northern flicker

depend on fruiting shrubs to provide important food resources,

and insectivores such as the olive-sided flycatcher and hermit

thrush require enough shrub and herbaceous understory in

coniferous forests to support the insect prey base. Shrubs and

grasses in pine-oak woodland settings are important to Gould’s

turkey, whip-poor-will, and Montezuma quail, and to Merriam’s

turkey in a variety of montane woodland settings, providing

insects as well as cover and roost sites. Pinyon pine and pinyonjuniper woodlands have also been subject to large-scale clearing efforts in order to improve forage availability for livestock.

The removal of these woodlands impacts several species,

including pinyon jays (that depend on mature, cone-bearing

pinyons), gray vireos (that utilize junipers for breeding), and

species such as the western bluebird that use juniper berries as

a source of food. Mast-producing oak trees are important for

turkeys and band-tailed pigeons and can be impacted by

continuous browsing that keeps them in a prostrate growth

form (GP 1999c).

Perhaps one of the most significant ecological interactions

between livestock and montane woodlands in the Southwest is

in the ponderosa pine forests. The natural state of old-growth

ponderosa pine forests is believed to consist of a relatively low

density of large diameter trees, widely spaced, with a grassy,

parklike understory. Fires in these systems are fueled primarily

by the grassy understory and are frequent but with relatively

low intensity. The larger trees are resistant to such fires, which

nevertheless burn out many new seedlings and other invading

woody species. Due in part to heavy livestock grazing in the

past century (as well as climatic factors such as drought),

ponderosa pine communities have changed through time, with

some now characterized by a dense cover of smaller trees.

Livestock grazing is thought to have contributed to fire suppression in these systems through the elimination of grass,

which is important to the spreading of the low intensity fires.

The depletion of competing grasses and lack of fire in turn

encourage the growth of shrubs and dense stands of young

conifers (dog-hair thickets). This has not only changed the

structure of the forest, but has also altered the fire regime to a

greater risk of large, hot, catastrophic events, rather than the

cooler, grass-fueled fires, which the larger trees are able to

withstand (Allen and others 2002; Chambers and Holthausen

2000; Covington and Moore 1994; Swetnam and others 1999;

Touchan and others 1996).

Several species are likely to be impacted by this change in

structure in ponderosa pine forests. The classic condition of

open ponderosa pine savannah with few mature trees is ideal

for the pygmy nuthatch, Lewis’ woodpecker, Grace’s warbler,

and olive warbler. Other species require a dense overstory in

concert with maintenance of an open understory for hunting

and foraging, including the northern goshawk, flammulated

owl, and northern saw-whet owl. Increased catastrophic fire

from dog-hair thickets threatens the habitat of a variety of

species, but fire also impacts the large mature trees that are

important as nest trees for primary cavity nesters such as the

northern flicker and as feeding substrates for bark gleaners

such as the brown creeper and pygmy nuthatch, which can be

driven out by severe fires (Lowe and others 1978). Several

species require diverse forest structure in which the presence

of large trees is an important component; these include the

Mexican spotted owl, western tanager, and hepatic tanager.

Grazing is not likely to impact the fire regimes of other forest

types such as mixed-conifer or spruce-fir, but the risk of

catastrophic fire in these forests may be increased if they are

adjacent to dog-hair thicket ponderosa pine forests. The ecological forest dynamics described above are also believed to be

at work in Madrean pine forests communities of southwestern

Arizona (Morrison and Martin 1997). Increases in dog-hair

thickets and risks of catastrophic fire could impact relatively

rare and highly local species such as the yellow-eyed junco,

Mexican chickadee, and buff-breasted flycatcher.

The availability of snags (standing dead trees) within a

diverse forest habitat is important for a variety of cavitynesting birds. Catastrophic fires may increase the number of

standing dead trees but effectively eliminate the habitat matrix

of existing snags within living habitat components. Thus,

grazing that indirectly contributes to increased risk of such

fires would threaten important nesting substrates for a variety

of cavity nesting birds, including woodpeckers, but also secondary cavity-nesting species such as the northern saw-whet

owl, flammulated owl, northern pygmy-owl, ash-throated flycatcher, violet-green swallow, elegant trogon, and others.

Open meadows interspersed among forest stands are also

important foraging and hunting areas for birds such as the

Mexican spotted owl, northern saw-whet owl, and northern

pygmy-owl. The grassy understory in these meadows often

supports prey for these bird species, which also need open,

unobstructed areas in which to hunt. The same ecological

dynamics among livestock grazing, fire suppression, and woody

shrub or conifer invasion can be at work in these areas. Prey

species can be driven out as grassy cover is eliminated, and as
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 27

shrubs and conifers invade a meadow, they can make it

structurally unsuitable for foraging. These conditions in meadows apply to a variety of forest types and elevations (not just

ponderosa pine); higher elevation forest meadows are also

important for species such as the violet-green swallow (foraging) and the broad-tailed hummingbird (foraging and mating

displays).

An important element of high-altitude woodlands that can be

directly impacted by ungulate browsing are aspen stands.

Large aspen trees are important substrates for nest cavities for

the hairy woodpecker, red-naped sapsucker, Williamson’s

sapsucker, and black-capped chickadees, and serve as an

important habitat component for some species such as the redbreasted nuthatch. Wild ungulates often have just as much if

not more impact on aspen as do domestic livestock; in some

areas, the impact from elk on aspen can be extremely high.

Intensive browsing or grazing in conjunction with fire suppression is thought to cause the recruitment of young aspen trees to

be sporadic or eliminated altogether (Dobkin and others 1995).

Heavy browsing of aspen “suckers” in the first several growing

seasons and during the initial growth period can eliminate a

sucker stand and deplete the parent root system. In addition,

ungulate use of adult aspens can scar the tree bole, which leads

to an increase in canker infections (Patton and Jones 1977;

DeByle and Winokur 1985).

Birds - Riparian Habitats—The importance of riparian

habitats to wildlife in the American West has been recognized

for some time. This is particularly true in the Southwest, where

broadly arid conditions magnify the importance of the mesic

habitat conditions found in riparian zones. Because of this,

birds and other terrestrial vertebrates occur in disproportionate

numbers in riparian areas of the Southwest and are particularly

vulnerable to degradation or alteration of these habitats (Cartron

and others 2000; Krueper and others 2003; Saab and others

1995).

Riparian situations exist at a variety of altitudes and under a

variety of climatic conditions that shape the distribution and

types of vegetation. All the habitat components that make them

attractive to wildlife also make them attractive to livestock:

succulent forage, water, and shade. While several authors have

identified livestock grazing as an important agent of change in

western riparian habitats (for example, Saab and others 1995

and authors cited therein), it should be noted that wild ungulates such as elk can also degrade or alter these habitats,

particularly in high-elevation systems. For birds and other

terrestrial vertebrates, it is this change in habitat structure and

composition, rather than the presence of ungulates per se, that

affects the suitability of riparian areas.

As with other habitat types, potential impacts from ungulates in riparian habitats can be both short term and long term.

Because riparian zones in the Southwest are frequently surrounded by sparser and more arid landscapes, riparian habitats

will often attract and concentrate livestock in high densities.

Thus, more immediate impacts can result from high stocking

densities and intensive grazing, which will likely eliminate

much of the available herbaceous vegetation and impact the

shrub layer through browsing and/or trampling. Riparian vegetation can often recover rapidly following removal of the

pressures exerted by ungulate use (Ohmart 1996). For example, Krueper and others (2003) report the impact of livestock removal in the San Pedro River National Conservation

Area (Arizona) on bird communities. The removal of cattle in

1987 resulted in a fourfold to sixfold increase in herbaceous

vegetation after 3 years, accompanied by significant increases

in a variety of bird species that are riparian specialists in the

Southwest. The increase in vegetation may have also induced

an increase in the insect prey base, as many of the species that

showed significant increases were primarily (if not obligate)

insectivores. This includes species in this database such as the

northern beardless-tyrannulet, western wood-pewee, ashthroated flycatcher, common yellowthroat, vermilion flycatcher,

Bewick’s wren, yellow-breasted chat, and brown-crested flycatcher. The interactions among livestock grazing, herbaceous

vegetation, insect diversity and abundance, and insectivores

have not been rigorously studied, and the panelists identified

these interactions as being in particular need of further research

(for example, GP 2001b).

In riparian habitats at low elevation similar to the situation

on the San Pedro River, substantial herbaceous and shrubby

vegetation support a variety of bird species, some of which (for

example, blue grosbeaks) are considered riparian obligates in

the Southwest. Dense, brushy riparian vegetation, including

willow thickets (usually with some component of tall trees; see

below), is a required habitat component for species such as the

blue grosbeak, Bell’s vireo, yellow-breasted chat, lesser goldfinch, indigo bunting, lazuli bunting, and painted bunting,

among others. The tall tree component is more important for

some species (such as the northern-beardless tyrannulet, lazuli

bunting, and willow flycatcher), but all require dense shrubby

understory for the habitat to be suitable. Dense mesquite

bosques that make up or are at least adjacent to riparian areas

appear to be important aspects of riparian habitat for several

species, including the phainopepla, Bell’s vireo, vermilion

flycatcher, and Lucy’s warbler. High cover of tall mesquite can

be important for Bullock’s oriole, yellow-billed cuckoo, western screech-owl, and buff-collared nightjar. All these species

could be negatively impacted by the clearing of mesquite,

small trees, or shrubs in xeroriparian washes or riparian habitats. The presence of cattle can result in browsing of important

thicket and brush components such as willow, as well as

opening dense understory shrubs through trampling and other

physical contact.

Besides removing riparian scrub vegetation, the presence of

livestock can also facilitate the establishment of exotic vegetation. Salt cedar (or tamarisk), a large, introduced shrub from

Asia, has proven to be especially invasive in Southwestern

riparian ecosystems. Its greater tolerance of drought and its

resilience in surviving and regenerating after fire has allowed

salt cedar to outcompete and replace native species throughout

the Southwest. In addition, livestock generally find salt cedar

to be unpalatable relative to native species, and will preferentially browse the latter, thus exacerbating the competitive
28 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

disadvantage of the native species (Cartron and others 2000).

Some studies have shown that salt cedar habitats support fewer

birds and less species diversity (for example, Anderson and

Ohmart 1985), while other studies have shown that for birds

requiring dense brushy riparian vegetation, these habitats

provide some substitute for native vegetation (for example,

Ellis 1995; Hunter and others 1985). Southwestern willow

flycatchers readily utilize salt cedar habitats of sufficient size

and density, as do the yellow warbler, summer tanager, Abert’s

towhee, song sparrow, and blue grosbeak. In the Grand Canyon, thickets of salt cedar support the Lucy’s warbler (Johnson

and others 1997), and on the Pecos River north of Carlsbad,

painted buntings are found almost exclusively in salt cedar

stands (Howe, personal communication). Bullock’s orioles

use salt cedar if it is very tall, although the birds avoid the

understory (Rosenberg and others 1991). It is generally believed that salt cedar provides poorer habitat conditions than do

native plant communities in good condition (Anderson and

others 1983 as cited in Cartron and others 2000) and that there

are sound ecological reasons to remove salt cedar and prevent

livestock from encouraging its establishment. However, in the

absence of native vegetation, it is clear that many species of

birds can successfully utilize salt cedar for breeding habitat in

Southwestern riparian zones.

At higher elevations, willow thickets and other dense streamside vegetation are also important to a variety of bird species.

Willow flycatchers at high elevations are found almost exclusively in willow habitats (Sogge and Marshall 2000), and

dense streamside thickets and ground vegetation are important

for the gray catbird, Lincoln’s sparrow, MacGillivray’s warbler, Wilson’s warbler, song sparrow, and orange-crowned

warbler. Some birds such as the Wilson’s warbler require no

tree overstory (Finch 1989), whereas others (for example,

orange-crowned warblers) require an overstory of ponderosa

pine, Douglas-fir, spruce, or aspen (Sogge and others 1994). In

addition to livestock, elk and deer can also heavily impact

willow thickets and other riparian shrub vegetation, particularly when population densities increase beyond natural carrying capacities. It should also be noted that beavers and their

systems of dams and lodges often raise water tables and create

pond systems that allow willow thickets and other riparian

shrub communities to become established. Thus, elimination

of these animals and destruction of their dams may ultimately

have an indirect impact on the habitat needs of these birds (see

further discussion below under Mammals).

Among the most important features of riparian habitat in the

Southwest are the large deciduous trees that can form large

gallery forests with tall, enclosed canopies. At low elevations,

cottonwoods and in some areas sycamores dominate these

deciduous forests. Depending on location, other trees such as

walnut, oak, and ash can also be major components of the tall

deciduous canopy. Continuous grazing or browsing in a riparian area can affect these trees over long periods by eliminating

recruitment of new trees into the forest community. New

saplings of cottonwood and other deciduous trees may be

preferentially browsed by ungulates as well as trampled when

first sprouting; these impacts on new trees eventually create

even-aged, nonreproducing stands (Cartron and others 2000

and authors cited therein). Mature forests of a single-age

structure can provide benefits to birds for many years after the

impacts of grazing have already been initiated, but without

replacement of dying and decadent trees, this habitat component will eventually be eliminated. In addition to browsing,

water diversion and flood control projects in streams and rivers

can also affect recruitment of species such as cottonwoods,

which require periodic flooding to allow seedlings to become

established.

The tall trees and high canopy of riparian gallery forests are

essential elements for a variety of birds that use them for

nesting and foraging. In far southeastern Arizona and southwestern New Mexico, large, mature riparian trees are required

by the zone-tailed hawk, common black-hawk, thick-billed

and tropical kingbirds, Bullock’s and hooded orioles, rosethroated becard, summer tanager, and others. In the Southwest,

Cooper’s hawks are mainly riparian birds, using the tall trees

for nesting (GP 2000e). Wild turkeys will use the tall trees for

roosting habitat. Many species utilize cottonwood-sycamorewillow associations containing a dense brushy understory or a

multiple-layer canopy, including the Southwestern willow

flycatcher, blue grosbeak, Abert’s towhee, and lesser goldfinch. Yellow-billed cuckoos require closed canopies with a

substantial subcanopy; yellow warblers utilize all vegetation

layers within riparian forests of cottonwood, box elder, and

willow. Sycamore stands appear to be preferred by some

species, including hooded orioles (Powell and Steidl 2002),

violet-crowned hummingbirds, which nest almost exclusively

in sycamores (Zimmerman and Levy 1960), and sulphurbellied flycatchers, which are found in sycamore/walnut riparian woodlands of deep canyons (Lowther and Stotz 1999).

Among specific habitat components provided by large mature cottonwoods and sycamores are nesting substrates for

cavity nesting birds. These trees and their associated riparian

habitats are important for a variety of primary cavity-nesting

species, such as the northern flicker and the red-headed,

Lewis’, and acorn woodpeckers (the last of which also requires

mature, mast-producing oaks). The Gila woodpecker, a denizen of the Sonoran desert and its saguaro stands in Arizona,

also nests in mature cottonwoods; in New Mexico it is considered an obligate riparian species (Edwards and Schnell 2000;

GP 2000c). Cavities constructed by these species, as well as

natural cavities, become important for secondary cavity nesters in riparian zones, including common mergansers, wood

ducks, black-bellied whistling ducks, elf owls, western screechowls, ash-throated and brown-crested flycatchers, black-capped

chickadees, white-breasted nuthatches, and violet-green swallows. Some species more frequently use cavities in sycamore

trees, such as the elegant trogon and whiskered screech-owl.

For all these birds, maintenance and continuous recruitment of

tall, mature deciduous cottonwood and sycamore trees in

riparian woodlands is essential to provide suitable nesting

habitat.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 29

Up to this point, the discussion has primarily focused on lowelevation riparian woodlands. This emphasis is justified by the

fact that, throughout desert or arid grassland environments,

these are frequently the only habitats available with tall tree

structure and mesic conditions. However, in higher elevation

systems, deciduous riparian woodlands provide important

habitat components for bird species that also utilize surrounding coniferous woodlands. Many species that are found in

lower elevation riparian woodlands also inhabit high elevation

cottonwood/aspen riparian zones (for example, white-breasted

nuthatch, black-capped chickadee, black-headed grosbeak).

Habitat requirements for species such as the western woodpewee and cordilleran flycatcher are characterized by riparian

deciduous trees within coniferous woodland. Swainson’s thrush

is a bird of montane coniferous forest, but with an affinity for

dense willow and alder thickets in riparian zones (Latta and

others 1999). Red-naped sapsuckers prefer aspens that are

located within riparian zones (Dobkin and others 1995), and

Mexican spotted owls require the cottonwoods and oaks of

montane riparian systems within coniferous forests to provide

the high structural complexity of vegetation for suitable roostsite structure (Stacey and Hodgson 1999). In southeastern

Arizona, montane canyons of pine-oak woodland characterized by riparian deciduous trees (particularly sycamore) with

pine at the edge are characteristic habitat for species such as the

elegant trogon, blue-throated hummingbird, and whiskered

screech-owl. In all these riparian habitats, the same impacts of

livestock and wild ungulate grazing, browsing, and trampling

(short-term effects of herbaceous and shrub cover removal;

long-term impacts on recruitment of large deciduous trees)

have the potential to affect habitat suitability for the bird

species in these systems.

In addition to direct effects on vegetation, livestock grazing

and range management can impact the availability of water and

water quality in riparian stream systems. Heavy livestock use

can lead to soil compaction and lowering of the water table, and

large numbers of livestock can reduce water clarity and quality

by increasing erosion and sedimentation and by polluting

waters with waste. Reduction in the availability of water can

negatively affect riparian vegetation and the habitat suitability

of birds, as discussed above. Degradation of water quality can

also impact various aquatic organisms (including fish, aquatic

insects, and other invertebrates), and thereby have an indirect

effect on the birds that feed on them. Bald eagles and osprey,

which also require tall riparian trees for nest platforms or

perches, both feed on larger species of fish. The common

black-hawk feeds on animals such as fish, frogs, and crayfish,

and occasionally hunts aquatic prey by wading in shallow

pools (Schnell 1994). The American dipper is a specialist of

high-altitude streams and creeks, foraging entirely in the water

for aquatic invertebrates (Kingery 1996). The common merganser also requires clear, fresh water for foraging in the

streams and waterways within forest zones (Johnsgard 1975).

Other riparian species may be characterized more by other

dietary needs but have some dependence on aquatic prey

during part of their life cycle. For example, the blue-throated

hummingbird is better known as a flower-feeding nectivore,

but during some parts of the breeding season it feeds exclusively on small insects that swarm in high abundance over

creeks and streams (Kuban and Neill 1980; Wagner 1946); this

may explain the importance of water sources in association

with its territories. For all these species, dependence on aquatic

organisms for prey will require clear, fast-flowing, and unpolluted water sources in order to maintain suitable habitat.

As mentioned above, water availability is an important

feature of wildlife habitat in Southwest riparian systems, and

there are mechanisms by which grazing or management can

both negatively and positively impact this availability. The

impacts of heavy livestock usage on water tables were mentioned above, but natural springs and creek systems can also be

drawn down or eliminated if water is collected into tanks or

otherwise developed for livestock use. However, the presence

of artificial stock ponds or tanks in general can often provide

water for wildlife where none would have otherwise existed.

This can benefit woodland birds such as wild turkeys, which

need a source of open water, as well as birds that forage for

insects over open water, such as the black phoebe and the

violet-green swallow. Large earthen ponds can be especially

beneficial for birds if shoreline vegetation is allowed to grow

and create stands of brushy riparian habitat and/or emergent

vegetation. Stock tanks can also be used in active management

by providing alternative water sources for livestock away from

streams and creeks, thus preventing the high concentrations of

livestock that cause damage to riparian ecosystems.

Birds - Wetland/Marsh Habitats—Of all the water-dependent habitats in the Southwest, the rarest and most ecologically fragile are probably the wetlands and marshes. Numerous

species of birds are rare or sparsely distributed in the Southwest

because their required habitats are as well. The American

bittern, least bittern, common moorhen, snowy egret, sora, and

the Virginia rail utilize habitats that are generally characterized

by shallow water marshland with dense stands of emergent

vegetation, often interspersed with areas of open water. Marsh

vegetation includes sedges, rushes, and cattails, sometimes

with a willow component on the shorelines. Some species (for

example, great egret, black-crowned night heron) also require

scattered tall trees for nesting or roosting; others are more

frequently found in marshland associated with deeper water

(for example, yellow-headed blackbird). Most marshlands are

found at low elevations, but other species use this habitat type

in high-elevation moist meadows (for example, common snipe).

The impacts of livestock on these habitats are varied, but it

is one of the few habitat types in which the panelists considered

livestock use to have a consistently negative impact and

therefore to be generally incompatible with habitat maintenance (GP 2001c). Marshes with tall emergent vegetation are

fragile and highly sensitive to the impacts of livestock and

grazing. Livestock can have immediate impact on this vegetation by trampling, opening up dense stands or even eliminating

patches of emergent vegetation. Heavy livestock use can also

lead to channelization of water courses and drying of marshes,

making them susceptible to fire. Water quality can also be
30 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

impacted by excessive stocking densities. The underlying

substrate of the marsh is typically rich in organic nutrients and

aquatic invertebrates, thus supplying important food resources

for many marsh birds. These conditions can be degraded by

livestock that trample this muddy substrate, increase water

sedimentation, and introduce large amounts of animal waste.

In addition, overgrazing can lead to increased erosion and silt

runoff into wetlands. However, it should also be noted that

limited trampling of marsh vegetation after the avian breeding

season can have a positive effect by introducing organic matter

into the marsh substrate, leading to increased invertebrate

productivity (GP 2001c).

Various range management activities can also affect marshlands and the required water supplies necessary to maintain

proper depths. Draining of marshes or diversion of water for

livestock use can have negative consequences for a number of

species as their habitat is eliminated. In the case of the American bittern, conversion of marshes to pasture has caused

population losses in northern New Mexico. Short of actual

elimination or conversion of marshes and wetlands to

pasturelands, activities that result in habitat fragmentation or

even altered vegetation structure and composition can have

detrimental effects (GP 2001c).

Numerous studies have been conducted on the effects of

cattle grazing on ducks and other waterfowl species. Braun

(1978, as cited in Ryder 1980) reported that at least 55 studies

had shown grazing to be detrimental to waterfowl production.

In reviewing the available literature, Kirsch (1969) was unable

to find any example where grazing or other cover removal

activity increased waterfowl production. When disturbed by

cattle, breeding pairs of waterfowl tend to move away from

cattle grazing and concentration areas (Kirsch 1969). In addition, activity that reduces residual vegetative cover may adversely affect waterfowl production because most waterfowl

species begin to nest prior to the availability of new growth

suitable for nesting. The presence of the previous year’s

residual cover permits hens to nest earlier; this provides a

longer period for renesting (Leopold 1933 as cited in Kirsch

1969). Cover removal by grazing (Kirsch 1969) and by other

sources of land development such as haying, mowing, and

cultivation (Drewien 1968 as cited in Kirsch 1969) adversely

affects breeding populations. Kirsch (1969) also reported

higher nest densities and nest success rates in ungrazed or idle

lands compared to grazed areas. Hoff (1993) found similar

results in wetlands of the White Mountains of Arizona: decreased vegetative cover due to cattle grazing led to decreased

numbers of breeding pairs, nesting density, and nest success of

ground-nesting waterfowl. Alterations to vegetation composition and structure that reduce available cover also make ducks

more vulnerable to predation (GP 1999d, 2001c). Also, excessive grazing has been found to reduce pond use by broods of

ducks (Kantrud 1986 as cited in Weller 1996). Many species of

ducks (for example, the northern pintail, American wigeon,

gadwall, green-winged, and cinnamon teal) require dense

terrestrial vegetation during nesting, and grazing can potentially degrade upland vegetation used as nesting habitat (GP

2001c).

Certain range practices could result in benefits for various

species of ducks. For example, nest success for the American

wigeon could be enhanced by grazing and burning practices

that encourage brush and brush/grass vegetation height greater

than 25 cm (10 inches) at the time of nesting (Mowbray 1999).

In addition, irrigated pastures and stock tanks can have positive

effects on all these species during migration and winter (GP

1999d, 2001c).

Birds - Ground Nesting—Many species of birds in this

database are ground-nesters, building nests and/or laying eggs

directly on the soil surface. It is these species that are most

likely to suffer directly from the presence of livestock (Saab

and others 1995), particularly when stocking densities are high

and the chances of trampling of nests and eggs are greatest. In

grasslands, this includes species such as the long-billed curlew, northern bobwhite, eastern meadowlark, savannah sparrow, grasshopper sparrow, vesper sparrow, and lark bunting; in

desert-scrub or arid woodlands, species such as the common

poorwill and whip-poor-will. High-elevation riparian willow

thickets support ground-nesters such as the Lincoln’s sparrow,

Wilson’s warbler, and orange-crowned warbler, and mountain

meadows have ground-nesters such as common snipe. In the

more southerly mountain regions, this category also includes

the yellow-eyed junco of pine-oak woodlands and the painted

redstart of riparian/coniferous woodland habitats. Many marshland birds (for example, all bitterns and rails) are low-nesters

in shallow waters. Gjershing (1975) reported increased nest

trampling by livestock on wetland shorelines. All of these

species, as well as other ground-nesters, may experience nest

failures due to trampling or other disturbances when livestock

densities are high.

Birds - Cowbird Parasitism—Certain species of passerine

birds are particularly vulnerable to brood parasitism by the

brown-headed and (less frequently) bronzed cowbirds. Brood

parasites lay their eggs in the nests of the host species, many of

which raise the cowbird chick in addition to or even instead of

their own young. High levels of brood parasitism can cause

reductions in reproductive output and eventually lead to population declines in the host species. The brown-headed cowbird

feeds on the ground, utilizing areas of short grass and bare

ground. Historically they likely followed bison herds through

the short-grass prairie region but later became associated with

the herds of livestock introduced by Euro-American settlers.

Brown-headed cowbirds have increased in abundance in many

areas of North America during the last century due to the

expansion of livestock herds, corrals, and feedlots, and the

birds’ ability to exploit human-provided resources of hay,

seeds, and grain (Robinson and others 1995).

Cowbird densities tend to increase with the presence of

cattle, thus the introduction of cattle into passerine bird habitats can potentially lead to increased opportunities for cowbird

parasitism (Goguen and Matthews 1999). This appears to be

particularly true in riparian areas of the Southwest, affecting
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 31

Bell’s vireo and the willow flycatcher (Franzreb 1989; Stoleson

and Finch 2000; see also references reviewed in Saab and

others 1995), but it can also include pinyon-juniper woodland

(Goguen and Matthews 1998) up to ponderosa pine and Douglas-fir forests (Hejl and Young 1999). However, the presence

of cattle is not by itself a sufficient condition leading to

increased parasitism rates. For instance, the willow flycatcher

is one species that is threatened by cowbird parasitism, but

whereas some populations are heavily parasitized, others show

only low or moderate levels, even when adjacent to grazed

areas (Boren 1997; Harris 1991; Whitfield and Strong 1995).

In addition, loss of habitat in riparian zones can confound

attempts to assess the impact of cowbird parasitism on passerine birds in these areas (Rothstein 1994 as cited in Cartron and

others 2000). In general, the panelists recognized (1) that in the

Southwest cowbirds are associated with concentrations of

domestic livestock, (2) that cowbird parasitism can negatively

affect host productivity, and (3) that certain populations of

some species (such as Bell’s vireo, Southwestern willow

flycatcher) are known to be negatively impacted by cowbird

parasitism.

Mammals – Introduction—As with other taxa, the effects

of grazing and range management on mammals are chiefly

related to the short-term and long-term impacts on the structure

and composition of vegetation in the various communities of

the Southwest. The general impacts on the different vegetation

communities as discussed above under Herpetofauna and

Birds will also affect the mammals that depend on these

communities. Although specific effects vary depending on the

habitats and other ecological requirements of individual species, the general issues of cover and food supply are critical

limiting factors for a variety of small mammals. Sufficient

groundcover (in the form of grass and forb cover as well as

woody debris and logs) is a widely shared habitat requirement

among various species of small mammals, including chipmunks, voles, mice, rats, and shrews. Many of these small

mammals are also granivores, thus requiring the seeds produced by grasses and forbs.

In addition to these issues, several species of large mammals

come into direct competition with livestock for forage, or prey

upon livestock, thus creating special challenges for range

managers. Domestic livestock (including cattle, sheep, and

goats) can experience competition for forage with large ungulates such as elk and deer, but also with species such as

pronghorn, bighorn sheep, and even bear. Livestock and range

management practices also complicate the ecological interactions among top predators, small carnivores, and their prey

species; not only can prey populations be reduced to levels that

can no longer support predators, but actions taken against

particular species of predator can have indirect effects on that

species’ suite of predatory competitors. The summary discussions of general habitat types below mainly focus on small

mammal species, followed by separate discussions of large

mammal interactions including competitors and predators of

livestock.

Mammals – Low-Elevation Grassland Habitats—Many

Southwestern mammals rely on the cover and food resources

provided in the grassland habitats located below high-elevation forested zones, with some even responding negatively to

increases in shrub and tree cover. Some species need dense

grass cover (and generally respond negatively to any grazing)

whereas others prefer sparser conditions (their responses vary

depending on grazing intensity and the type of grassland).

Perhaps no other species relies on pure grassland conditions

more than the white-sided jackrabbit, a specialist of plains and

desert grasslands. This species requires well-developed grass

cover and virtually no shrubs (Bednarz and Cook 1984). The

white-tailed jackrabbit also inhabits grasslands but can be

found from plains grasslands to alpine tundra; it is slightly

more tolerant of shrub cover. Both of these species succumb to

competition with the black-tailed jackrabbit when shrub densities increase (GP 2001d). Other species requiring dense grass

cover are the tawny-bellied and hispid cotton rats (both of

which require tall grasses for construction of “runways”;

Baker and Shump 1978), northern pygmy mouse, and fulvous,

western, and plains harvest mice. These species can be expected to respond negatively to grazing that depletes the

required dense, grassy or weedy groundcover and, over the

long-term, facilitates the encroachment of dense stands of

mesquite and/or other shrubs into grassland habitats (see

discussion above under Birds; also Milchunas, in press). Many

of these species are also granivores that depend on grass and

forb seeds for food resources and can be affected if these are

prevented from developing. Other species (such as the hispid

and silky pocket mice, and the thirteen-lined ground squirrel)

are less dependent on tall, dense grass cover, and are more

frequently found in short-grass or arid grasslands. In these

cases, grazing may be beneficial to these species in dense

productive grasslands by opening the herbaceous layer and

creating some open ground. Grazing would have greater negative effects in the sparser desert grasslands where productivity

is lower and grass cover and seed production are more easily

eliminated.

Burrowing rodents in Southwestern grasslands can be impacted by high stocking densities that not only eliminate

grasses and forbs but also compact soils and trample burrow

systems. This is particularly true of the kangaroo rats (in

grasslands, the Ord’s and banner-tailed kangaroo rats). As

granivores, these rodents are also impacted by reductions in

grasses and the seeds they provide, and they also respond

negatively over time to high levels of shrub encroachment into

grasslands (Fagerstone and Ramey 1996; Krogh and others

2002). Kangaroo rats construct elaborate burrow systems that

create above-surface mounds that are susceptible to trampling;

furthermore, these mounds may make them subject to eradication efforts by land managers who perceive the mounds as a

threat to livestock (GP 2001e). Such impacts extend beyond

these species because the burrow systems are important features of the surrounding landscape for a wide variety of arid

grassland species (Hawkins and Nicoletto 1992). Soils must be

friable and allow extensive burrowing; thus high stocking
32 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

densities that concentrate cattle and result in high levels of soil

compaction can make soil habitats unsuitable for these species.

Kangaroo rats utilize fine-textured sandy soils (Ord’s) to clay/

gravel soils (banner-tailed) for burrow construction. Other

grassland burrowing mammals such as the yellow-faced pocket

gopher utilize deep, sandy or silty soils (Davidow-Henry and

others 1989; MacMahon 1999). Pocket gophers in general

depend upon air diffusion through soils, so their tunnels do best

in light-textured porous soils (Fagerstone and Ramey 1996).

Perhaps the most well-known burrowing rodents that interact with livestock in the low-elevation grasslands of the Southwest are the prairie dogs. The ecological interactions here are

complicated by the other species of wildlife that either depend

on the prairie dog for food, or depend on their burrow systems

for cover (for example, burrowing owls, as discussed earlier,

and swift and kit foxes, which modify prairie dog burrows for

their own use). In general, the grazing panel determined that,

while prairie dogs suffer from eradication efforts on rangelands, the level of competition for forage between prairie dogs

and cattle has likely been exaggerated, and that livestock and

prairie dogs may even confer beneficial ecological effects on

each other (GP 2001d). Prairie dogs prefer areas with short,

sparse vegetation and compact soils. Studies have shown that,

while prairie dogs can change the types of food plants in an

area, they do not significantly decrease the amount of weight

gain in cattle (for example, O’Meilia and others 1982), and the

elimination of prairie dogs has had little effect on increasing

the amount of food available for cattle (Collins and others

1984; Crocker-Bedford 1976; Klatt and Hein 1978; Uresk

1985—all as cited in Fagerstone and Ramey 1996). Other

studies indicate that prairie dog foraging, while reducing

overall forage quantity, creates high quality regrowth and

produces plants with greater palatability for cattle (for example, Coppock and others 1983; Krueger 1986; O’Meilia and

others 1982; Whicker and Detling 1988); likewise, reasonable

levels of domestic livestock grazing can actually increase the

nutritional quality of the forage for prairie dogs (GP 2001d).

Range improvements that result in a concentration of cattle can

be positive if, through the trampling and grazing of taller

vegetation, they create conditions that aid dispersal and expansion of prairie dog colonies (Knowles 1985, 1986 as cited in

Wuerthner 1997). One irony of the eradication campaign is

that the elimination of prairie dogs may have led to an increase

of a number of woody plants (such as mesquite), thus exacerbating shrub encroachment into grasslands (see Weltzin and

others 1997). The poisoning of prairie dogs should also be

considered in regards to its impacts on nontarget species; the

use of poisoned seed baits can be detrimental to a variety of

granivorous rodents in grassland ecosystems (GP 2001d).

Finally, a number of mammalian predators prey on prairie

dogs, none as much as the endangered black-footed ferret,

which relies almost entirely on prairie dogs for food (Campbell

and others 1987).

Of large mammals in low-elevation grassland habitats, perhaps none are as reliant on the vegetative productivity of these

communities as the pronghorn. Pronghorn inhabit large areas

of open grassland and shrub-steppe and require areas with low

(less than 5 percent) shrub coverage (Yoakum and others

1996). In addition, they rely on abundant forb coverage for

food, along with some species of small shrubs. Livestock can

impact these habitats by eliminating forb and palatable shrub

coverage in the short term (mostly by sheep - GP 2001f;

Howard and others 1990) and by facilitating shrub invasion

(especially taller shrubs) through selective grazing over the

long term. In addition, net wire and close-strand barbed wire

fences can cause artificial habitat fragmentation by restricting

pronghorn movement to water and forage, especially as availability of these resources becomes limited by drought or

excessive livestock use (GP 1999e; Yoakum and others 1996).

Other large ungulates also utilize low-elevation grassland and

shrub-steppe habitats and the forage they provide (for example, desert bighorn sheep) but are generally not as reliant on

these as is the pronghorn. Interactions among livestock and

their large ungulate competitors are discussed more fully

below.

Mammals - Desert Scrub Habitats—Several mammals

require a significant shrub component in desert grasslands or

desert scrub. As discussed for birds, potential negative effects

come from high densities of livestock that degrade the shrub or

cactus components and management activities that clear away

shrubs and cactus in order to create grassland habitats; increases in shrubs facilitated by grazing on herbaceous vegetation will often benefit these mammals.

Among small mammals, some may be considered grassland

species that also require a low density of shrubs or trees. For

example, the southern plains woodrat occupies well-developed desert grasslands and is expected to respond negatively to

increases in the densities of shrubs. However, it occupies

grassland with cactus or yucca, as well as savannahs with

mesquite or shinnery oak; in addition, the joints of Opuntia

cacti are a preferred food resource (Braun and Mares 1989; GP

2001d). Such a “transitional” species between grassland and

scrubland could be negatively impacted by grazing-facilitated

shrub encroachment, but also by clearing efforts to create pure

grassland for livestock.

The preference for shrub habitats is stronger in other rodent

species. The chisel-toothed kangaroo rat, in contrast to the

Ord’s and banner-tailed kangaroo rats discussed above, needs

good shrub cover and is especially affected by browsing or

trampling of saltbush (Larrison and Johnson 1973). The Arizona and desert woodrats are often tied to rocky areas, but also

rely heavily on desert scrub as a food source and for cover

(Smith 1995a,b). Golden-mantled ground squirrels can benefit

from grazing in arid grasslands when the grazing results in

increased shrub cover and reductions in the height of the

herbaceous layer, but the squirrels are negatively impacted by

shrub removal. The mesquite mouse is a denizen of xeroriparian

thickets of mesquite, a habitat that is now considered localized

and fragmented to some degree because of clearing as part of

range improvement activities (AGFD 1996; Armstrong 1999).

Large mammals such as peccaries and the desert subspecies of

the mule deer also prefer areas where thick, tall shrubs with

thickets of cacti provide cover, food, and moisture (GP 2001f).
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 33

Agaves, saguaro cacti, and other flowering plants also provide important food resources for nectar feeding bats. The

endangered Mexican long-nosed and southern long-nosed

bats, as well as the Mexican long-tongued bat, feed not only on

the nectar of agaves and cacti, but also on jimson weed, wax

mallow, and mescal. They also rely on the cacti for fruits and

on other desert vegetation to support an insect prey base to

supplement their nectar diet (Hensley and Wilkins 1988;

Hoffmeister 1986).

As discussed above for birds, many Sonoran Desert habitats

can also be impacted by the spread of exotic grasses, which

increases fire frequencies to unnatural levels. Another effect of

the invasion by exotic grasses may be to reduce the availability

of preferred seeds for granivorous species. The seeds of red

bromes and African lovegrasses are smaller and of lower

nutritional quality than those of native grasses. Thus when the

latter are replaced by exotic species introduced for livestock

forage, food resources for granivores may be reduced (GP

1999e, 2001e).

Mammals - Woodland and Boreal Habitats—Within

many woodland habitats, many small mammal species still

depend mostly on the grass and forb understories for cover and

food and thus are affected by impacts to these resources just as

in grasslands and scrublands. This is particularly true in

savannahlike ecosystems such as pinyon-juniper woodlands,

but there are many species that also rely on grass understory in

ponderosa pine forests as well as meadows between stands of

mixed conifer or spruce-fir. Still other species require “old

growth” conditions of open ponderosa pine forests or densecanopy mixed conifer or spruce-fir forests, and thus could be

potentially impacted by grazing regimes that, over the long

term, help create conditions that are at increased risk of

catastrophic fires.

Species such as the desert woodrat and fulvous harvest

mouse are often found in pinyon-juniper woodlands but usually occupy rocky areas containing grasses and shrubs interspersed among the trees. Likewise, the yellow-nosed cottonrat occurs in oak/pinyon/juniper woodlands but is more tied to

the bunchgrasses and other groundcover (although not as

reliant on mesic, dense grassy conditions as are the other cotton

rats). Cliff chipmunks mostly occupy rocky outcrops and cliffs

within these vegetative habitats, but consume the seeds and

berries of pinyons, junipers, and other trees. Thus, grazing

regimes that lead to increases in berry-producing trees and

shrubs can benefit cliff chipmunks and other species, but largescale clearing of shrubs and trees would eliminate suitable

habitat. Perhaps the most affected by such action would be the

Stephen’s woodrat, a specialist of juniper woodlands. While it

is often associated with rocky outcrops and rock piles at the

base of cliffs, its diet is almost completely composed of juniper

berries and leaves (Fitzgerald and others 1994; Hoffmeister

1986).

Much of the discussion of grazing impacts in ponderosa pine

woodlands centers on the long-term effects of fire suppression

leading to the growth of dog-hair thickets, which are at a

greater risk of catastrophic fire (see discussion above under

Birds and in Milchunas, in press). These effects on forest

structure can also impact species such as the spotted and

Allen’s big-eared bats, which navigate through open ponderosa pine stands and forage in open grassy areas, both of which

can be degraded by an increase in the density of small diameter

trees. However, the removal of the grassy understory, one of

the agents in the ecological interactions leading to dog-hair

thickets, can have a more immediate impact on the small

mammal species that use this habitat. The Mogollon vole in

particular relies on grassy groundcover in ponderosa pine and

other coniferous forests, especially when pushed out of more

mesic habitats through competitive exclusion by other voles

such as the montane vole (Findley and others 1975; Frey 1999).

It will not use grassy areas that are below a threshold necessary

for cover and building the runways that are characteristic of

voles (GP 2001g). For other species, such as the gray-footed

and gray-collared chipmunks, the berry and seed-producing

shrubs and small trees used for food and cover are the important habitat component, and are likely to be severely impacted

only at high densities of livestock consistently occupying the

forest understory.

Transitioning into mixed conifer and spruce-fir forests are

species such as the bushy-tailed woodrat and least chipmunk,

both of which use berry and seed-producing shrubs for food

and cover in high-elevation forests. Rocky outcrops interspersed within these forest types are also important to these and

other species. While cattle may not venture into these areas, the

grass and shrub cover may be subject to browsing by domestic

goats or wild ungulates such as bighorn sheep, elk, or deer. It

should also be noted, however, that these small mammals may

benefit from increased seed production of some shrubs and

trees under certain grazing regimes. Other species such as the

southern red-backed vole rely on mesic forest floor conditions

in spruce/fir/aspen forests, along with woody debris and logs.

High livestock use and trampling in these forests could result

in degradation of this cover, as well as churning up the forest

floor, drying it out, and making it unsuitable for this and other

voles reliant on mesic forest floor conditions. One species that

is considered a specialist of these forests is the red squirrel, an

inhabitant of mixed conifer, Douglas-fir, and Englemann sprucecorkbark/subalpine fir habitats (Findley and others 1975). Red

squirrels require damp, shady, cool environments to construct

pine cone storage middens, as well as dense understory canopy

and groundcover (Hoffmeister 1986; Young 1999), thus making it vulnerable to ungulate densities that result in an opening

of the understory, reduction in foliage volume, and/or the

reduction or desiccation of groundcover.

In the high-elevation regions of northern New Mexico, a few

small mammals occur near or above timberline that may be

impacted, if not by domestic livestock such as goats, then by

wild ungulate usage. Excessive grazing and browsing in sprucefir and boreal forest can lead to a reduction in cover and/or a

loss of desired forage species for snowshoe hares, which could

be subject to competition with domestic and wild ungulates for

grasses, forbs, and browse. Marmots also occur from sprucefir forests to above the timberline but are typically found
34 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

among boulders and rock fields. However, they require abundant lush vegetation prior to entering winter torpor as well as

after coming out in spring, and can be vulnerable to starvation

if such vegetation is not available. Likewise, the pika is a

denizen of talus slides and boulders above timberline and relies

on subalpine grassland and tundra grassland vegetation. We

lack information on the effects of grazing in these areas, but

depletion of the food resources here would likely be detrimental to this species (GP 2001d).

Mammals - Riparian and Wet Meadow Habitats—As

with birds, a number of mammals also rely on the vegetation

structure and/or mesic environments of riparian habitats. In

addition, there are several species, particularly among the

voles and shrews, that chiefly utilize or even specialize on

high-elevation wet meadows. These habitats are characterized

by muddy or even marshy or boggy soil substrates, lush

herbaceous vegetation, and typically little if any shrub cover.

As discussed above for birds, the various wetland habitats are

particularly vulnerable in the Southwest because of their rarity

and isolation within the larger arid landscapes of the region.

Among Southwestern riparian habitats, numerous species

utilize the shrubby understory for cover and food, but some

species are also strongly associated with the large deciduous

trees typical of cottonwood or sycamore riparian forests. Both

the Arizona gray squirrel and the Chiricahua subspecies of the

Mexican fox squirrel are strongly associated with riparian

woodland within various coniferous forests systems and thus

could be impacted by ungulate browsing that removes deciduous tree seedlings, leading to a lack of recruitment of these

trees. Oaks are also important to these squirrels and must be

able to grow and mature into the mast-producing stage. Adjacent to ponderosa pine forests, the issue of increased fire risk

becomes important, as fire within riparian woodlands is typically catastrophic.

Tall, dense grass in cottonwood/willow associations can be

important for some rodents such as the Arizona cotton-rat,

which needs heavy grass cover to construct the “runways”

characteristic of all cotton-rats. Pine-oak and desert riparian

areas with a dense understory of brush is important to species

such as the hooded skunk, and elsewhere at low elevations this

habitat is utilized by other small mammals such as the llano

(plains) subspecies of the eastern cottontail. Riparian scrub at

higher elevations often provides food and cover for other

species of cottontail, but also for chipmunks such as the grayfooted and gray-collared chipmunks. Species such as the

western jumping mouse inhabit alder-willow-aspen riparian

vegetation with a dense cover of grasses and forbs. In all these

cases, heavy grazing or browsing in conjunction with prolonged occupation by large numbers of ungulates can result in

the removal of both the shrub understory and the herbaceous

cover needed by these species.

Other species require wetland habitats with permanent water

and abundant emergent vegetation. As mentioned earlier, such

wetlands are generally incompatible with livestock use; in

addition, the water sources can be subject to depletion or

pollution. Representative species include the least shrew, the

muskrat, and the New Mexico meadow jumping mouse, all of

which require moist, dense grassy areas with emergent vegetation (spikerush, sedges, rushes, cattails) near marshes, ponds,

or riparian areas. The muskrat in particular is an aquatic

specialist, occupying all water habitats with sufficient vegetation (Willner and others 1980). The northern river otter, rare to

extirpated in the Southwest, requires permanent water with

similar vegetation as described above, and it is particularly

sensitive to pollution or increased sedimentation (Ceballos

1999). In addition to these species, the mink is an obligate

riparian specialist that formerly occupied the streams and

rivers of northern New Mexico (Bailey 1932); in addition to the

vegetation, it also requires abundant aquatic prey (for example,

muskrats and crayfish; see discussion of predator and prey

issues below).

No discussion of mammals and riparian habitats is complete

without including the American beaver. An inhabitant of

riparian wetlands with abundant willow and other woody

vegetation for browsing, the beaver is renowned for its system

of lodges and dams that alter the hydrology of stream systems

and create ponds of standing water. The resulting herbaceous

and woody vegetation at the shoreline and abundant water

supplies create wetland habitat for a number of bird and

mammal species. Willow and aspen are favorite food items for

beaver that can be reduced through competition for food

resources with large densities of ungulates, particularly elk

(Zeigenfuss and others 2002). Continuous water flow and good

water quality are additional habitat requirements that can be

impacted by the presence of large numbers of livestock or by

range improvements meant to increase livestock access to

water. Beaver dams can be targeted by people wishing to

eliminate ponds and increase areas of vegetation for livestock,

but the presence of beaver can also potentially improve conditions for livestock through raising water tables, stabilizing

water regimes, and promoting riparian forage (GP 2001d;

Olson and Hubert 1994). In the Southwest, beaver ponds have

proven to be important sources of water for agricultural uses

during droughts (Albert 1999).

Wetland areas and wet meadows support a variety of species

of voles and shrews that rely on the mesic conditions and dense

herbaceous vegetation provided by these habitats. As stated

above, these areas are characterized by saturated soils, bogs, or

marshes, with a grass/sedge community that is frequently thick

and dense. Most are high elevation, montane habitats, but some

of the species mentioned occupy these types of habitats at all

elevations. The montane vole is perhaps the vole most associated with these conditions within coniferous forest zones,

which also support the meadow vole (also found at lower

elevations) and the Mogollon vole (also found in drier grassy

areas). Long-tailed voles are also found in these habitats in

concert with shrubby riparian areas. Among the shrews, the

cinereus (or masked) shrew inhabits boggy or marshy fields as

well as willow thickets and (relatively) drier forest thickets;

this is also true of the montane and New Mexico shrews. Many

of these shrews also require abundant groundcover in the form

of logs or woody debris in addition to a generally moist
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 35

environment. The most aquatic is the aptly named water shrew,

which requires running water at high elevations, undercut

streambanks, and luxuriant grass cover, and feeds on aquatic

insects (Beneski and Stinson 1987).

Numerous populations of microtine voles in the Western

United States may be near extinction because the highly

limited moist habitat on which they depend is also attractive to

people and livestock (Nowak 1999), and grazing can negatively impact wetland habitat in a variety of ways. Alteration

of vegetation structure and composition can affect the quality

of habitat available. For example, montane voles require a

thick cover of grass or forbs, and livestock grazing causes

strong decreases in montane vole numbers, in some cases even

the local disappearance of the species (Fagerstone and Ramey

1996; Kauffman and others 1982; Medin and Clary 1989).

Birney and others (1976) suggest that a threshold level of grass

cover is necessary for meadow voles to reach peak population

densities. Hence, grazing activities that suppress vegetative

cover below the threshold may restrict populations. In addition

to removal of cover by grazing, wet vegetated meadows and

spring seeps are highly fragile and susceptible to trampling that

causes soil surface distortion (“plowing” of the surface by

hooves) and degradation of cover, both of which would render

this habitat unsuitable for many voles and shrews. High ungulate densities and soil compaction can also stop seeps and

springs from flowing and eliminate required habitat. These

effects can be exacerbated by periodic cycles of excessively

dry climatic conditions experienced in the Southwest (GP

2001g,h).

Mammals - Large Herbivore Interactions—Livestock

will have the greatest ecological interactions and competitive

effects with similarly sized herbivorous mammals, particularly those species that are most closely related to the livestock

(for example, bighorn and domestic sheep). Deer, elk, bighorn

sheep, and pronghorn can all come into conflict with livestock

for palatable vegetation, and in some cases the transmission of

disease can be an issue. For many of these species of wild

ungulates (especially elk), the panelists considered them as a

priority when selecting grazing strategies because land managers must consider the effect of both the wild ungulates on

habitat as well as the effects of the domestic grazers upon the

wild ungulates (GP 2001i).

The effect of grazing on mule deer is much debated. These

effects are probably quite variable depending on habitat type,

vegetation structure and composition, and the intensity and

duration of grazing. Grazing is generally detrimental in arid

and semiarid habitats and less detrimental in chaparral and

other more mesic habitats, with the exception of mountain

meadows where competition can be severe (GP 1999e). Vegetation changes may influence mule deer survival and recruitment. Several studies suggest a correlation between grazing

intensity and local fawn survival. In addition, grazing that

reduces succulent vegetation during fawning and early lactation could potentially reduce fawn survival (GP 2001i). Grazing as well as fire and other vegetation disturbances that

promote shrub seral stages may be of benefit to mule deer (GP

1999e; Julander 1955, 1962). However, vegetation disturbances that decrease shrubs and herbaceous plants or fail to

maintain a young and vigorous seral stage will be detrimental

(Julander 1955, 1962).

Many of these same issues apply to white-tailed deer: heavy

grazing has the potential to decrease residual groundcover,

important for hiding fawns, and reduce forbs for forage.

Additionally, brush management practices used to increase

herbaceous vegetation for livestock may reduce preferred

browse species and reduce or eliminate escape cover. Grazing

systems that increase availability of browse and improve

nutritional quality of forage may be of benefit, and enhanced

water availability associated with stock operations may improve suitability of habitat (GP 1999e, 2001i). Recent dietary

information indicates a potential overlap of diet between elk

and Texas white-tailed deer (Odocoileus virginianus texana),

where both species occur (Tafoya and others 2001). Therefore,

where multiple species of native ungulates occur, management

practices should take grazing by these natives into account, as

well as grazing by domestic livestock, when creating grazing

management plans (GP 2001i).

The effect of livestock grazing on elk has not been well

documented, and there are differing reports on the effects of

grazing on elk (GP 2001i). In areas of heavy livestock grazing

the effect on elk can be negative because of competition for

forage, inappropriate changes in vegetation structure and composition, and changes in fire regime leading to the loss of

adequate forage and cover areas (GP 1999e). Competition—

defined as an interaction through which both species suffer

reduced survival or lower reproductive success (Wagner

1983)—has not been documented between elk and cattle (Edge

and Marcum 1990). Potential conflicts between elk and cattle

focus on dietary overlap, common use of space, and social

incompatibility (Edge and Marcum 1990). Competition can

occur only if elk and livestock are using the same area, forage

species are in short supply, or elk and livestock are using the

same forage species (Holechek 1980). Other authors report

that elk use appears to be inversely related to cattle use (Nelson

1982); in other words, less cattle use equals more elk use.

Under certain management regimes and stocking levels,

grazing may have a positive influence on elk in Arizona and

New Mexico. Elk have increased in distribution and numbers

due to the conversion of dense forests to earlier successional

stages through moderate livestock grazing, reductions in overstory vegetation, seeding projects to increase herbaceous vegetation, and water developments (GP 1999e).

Disease transmission from livestock (primarily domestic

sheep) to bighorn sheep is the primary detrimental impact to

this species from livestock grazing and ranching. Domestic

livestock diseases infect bighorn sheep and are known or

strongly suspected to cause significant mortality, including

extinction of local populations (Dunn 1996 and authors cited

therein; Foreyt and Jessup 1982). Competition for forage and

alteration of vegetation structure and composition are also

important negative effects from livestock grazing, and in the

case of cattle these are more important impacts than disease
36 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

transmission (Krausman and others 1996). Pronghorn in shrubsteppe are discussed above under Low-Elevation Grassland

Habitats, but they too can interact with livestock via transmission of disease organisms: cattle may act as a reservoir for

bluetongue, a disease highly fatal to pronghorn (Yoakum and

others 1996).

In addition to large ungulate herbivores, livestock can also

come into competition with black bear for important food

resources. Grass cover in the springtime near den sites is

important for the survival of cubs, therefore any grazing

intensity that results in the reduction of spring grasses will

likely have a negative impact on black bear (GP 2001j).

Pregnant females require much greater fat deposits going into

winter hibernation than do nonreproductive females (Harlow

and others 2002); thus, reproductive success in this species

may be reduced if vegetative food resources are not available

prior to the hibernation period. Habitat treatments that reduce

oak, juniper, or other mast-producing plants would have negative effects on black bear, but any treatments that stimulate the

growth of mast-producing plants could be positive (GP 2001j).

Mammals – Predator Interactions—Whereas many wildlife species are affected by grazing through direct impacts on

the vegetative components of their habitat, the effects on

mammalian predators are varied and complex. There are

multiple indirect effects among competing predators, prey

species, as well as other species not directly associated with the

predator-prey interactions. Livestock themselves are often

potential prey, thus inducing management activities aimed at

controlling or eliminating large predators. This in turn has its

own effects, not only on potential wild prey species, but also on

competing predators in the larger community. Both large and

small predators can also be impacted by reductions in prey, and

if the prey species are also impacted by grazing effects, then the

effects can be amplified up the food chain.

Among large predators, the cougar, black bear, gray wolf,

and jaguar can be expected to occasionally take livestock.

Contemporary attitudes toward large predators tend to be

highly negative within the ranching industry, and intentional

killing of these animals is probably the key factor, related to

livestock management, that threatens these species. Cougar

will predominantly take sheep and goats, but also cattle and

horses. Black bear will take sheep, goats, and calves. Wolves

can learn to prey on livestock such as sheep, goats, and cattle,

and thus come into conflict with ranchers (GP 2001f). Jaguars

rarely wander into the United States and are not likely to inflict

many losses at this time. Research has shown that when

abundant natural prey is available, jaguars tend not to menace

livestock (Weber and Rabinowitz 1996).

Wolves were historically targeted by predator control operations, and the intentional killing of wolves resulted in the

extirpation of this species from Arizona and New Mexico

(Brown 1983; GP 1999e, 2001f). The absence of the wolf as a

major predator has likely had major effects not only on the

ungulate prey species but also indirectly on the vegetation used

by those prey. For example, research in Yellowstone National

Park indicates that wolves have an indirect positive effect on

aspen regeneration by altering elk foraging behavior and

browsing patterns (Ripple and others 2001). Research by

Berger and others (2001) suggests that, in high-elevation

riparian willow ecosystems, the lack of a top mammalian

predator can allow ungulate densities to increase, leading to

increased browsing on willow and in turn reduced densities of

birds that use these riparian habitats. Thus, management approaches that allow wolves to interact with their natural prey

species in Southwestern ecosystems should have broader positive effects on a variety of wildlife species and their habitats.

Predator-prey interactions are but one component of the

ecological processes through which wolves have indirect effects on other wildlife. The other component is the competitive

relationship that wolves have with other canids such as the

coyote and the red fox, and the impact these relationships have

on additional canids as well as small mammal prey species. In

Yellowstone National Park, the presence of wolves appears to

keep coyote populations in check (Arjo and Pletscher 1999).

The reintroduction of wolves here has led to a decrease in

coyote numbers by 50 percent along with a reduction of coyote

pack size; the wolves have been killing approximately 25 to 33

percent of the coyote population each winter (Crabtree and

Sheldon 1999). However, it should also be noted that these

declines are not expected to continue and should reach equilibrium as coyotes respond and adapt to a competing predator

with which it has co-evolved (Crabtree and Sheldon 1999;

Mlot 1998). Again, given that reintroductions of the gray wolf

have only recently been initiated in the Southwest, this has yet

to be demonstrated in this region; if realized, it would have

repercussions throughout the suite of competing canid species.

The coyote is a major competitor of the red fox, and its

expansion is believed to have had a negative impact on red fox

distribution (GP 2001j). Coyotes are also major predators and

competitors of the kit fox and swift fox (Ralls and White 1995).

Thus, reductions in coyote numbers would ultimately be

favorable to the fox populations in the Southwest.

Many smaller predators are not impacted as much by eradication efforts but can be affected by nonspecific trapping or

poisoning and by eradication efforts aimed at prey species.

Grazing or management practices that cause declines in small

rodent or rabbit populations may negatively impact species

such as the long-tailed weasel, kit fox, swift fox, red fox, and

bobcat. Several predator species rely on small mammals that

are also in this database. The red fox relies on prey such as the

Nuttall’s cottontail and the montane vole, among others (GP

2001j). The ermine also relies heavily on montane and meadow

voles, and the mink, a riparian obligate, relies on abundant

populations of muskrats as well as voles. The same holds true

for some birds as well; for example, the Mogollon vole is a key

prey species of the Mexican spotted owl in New Mexico (Ward

2001). Thus, management aimed at preserving these prey

species must not only provide the resources necessary to

sustain a minimum population size, it must also provide

additional resources for larger populations in order to maintain

a prey base for predatory species of concern.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 37

This assessment of the ecological interactions among native

wildlife species of the Southwest and grazing and range

management practices is designed to provide an informational

tool for the region’s land managers and biologists. The resulting database contains 305 accounts for species and subspecies

believed to be potentially vulnerable to both short-term and

long-term effects of native and domestic ungulate grazing.

Species were selected through a panel process that first derived

an initial list of species for the database and then utilized the

expertise of the panelists to review and amend individual

species accounts.

The accounts are included with this publication in the form

of a computer database (based on Microsoft Access) as well as

individual files for either on-screen viewing or printing of hard

copies (see appendix F for more details). The computer database allows the user to search for individual species by a

variety of criteria, including taxonomic affiliation, designation

of priority status, or by any shared selection of menu items

(described above in the Species Account Guide and in appendix B). Searches can also be made for species that share certain

elements of text within the text narrative blocks.

It is intended that this database be used in concert with the

geospatial databases provided in Bender and others (2005). We

assume that most land and range managers will usually be

interested in only a specific geographic area; the geospatial

database can help develop a list of species based on the

database included here as well as the distribution of vegetation

Summary _______________________________________________________

communities and predicted occurrence areas generated by the

geospatial database. Managers can also develop a species list

by searching the species account database by specific habitat

type, and then referring to the individual species distribution

information to winnow down the list to only those occupying

the area of interest. Also, additional information on grazing

impacts on the vegetative communities and vegetation components of habitats can be obtained in Milchunas (in press).

Once a list of species is generated, then additional queries

can aid in determining information such as shared habitat

requirements or other ecological parameters, as well as shared

grazing effects, fire regime requirements, and so forth. Priority species can be isolated from others on the list, and, in cases

of conflicting habitat needs or grazing effects, this can help

in developing a prioritization strategy when considering

conflicting needs of various species of wildlife and livestock

utilization.

Finally, users should keep in mind that research will continue on wildlife and grazing interactions, and the results will

undoubtedly alter some of the information contained in these

accounts. In addition, many of the species in the database may

prove to be tolerant of grazing, whereas others not on the list

may turn out to be more vulnerable than is now realized.

Therefore, it is highly recommended that users supplement this

database with a thorough literature search for material published after the date of this assessment.
38 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

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P. B.

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U.S. Department of the Interior (USDI) Fish and Wildlife Service. 2003. A

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Valdez, E. W.; Choate, J. R.; Bogan, M. A.; Yates, T. L. 1999. Taxonomic

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Society.
44 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Reptiles and Amphibians

Hakkila, Mark D. (I, II) Bureau of Land Management, Las Cruces, NM

Holm, Peter A. (II) University of Arizona, Tucson, AZ

Holycross, Andrew T. (I, II) Arizona State University, Tempe, AZ

Jennings, Randy D. (I, II) Western New Mexico University, Silver City, NM

Painter, Charles W. (I, II) New Mexico Department of Game and Fish, Santa Fe, NM

Persons, Trevor B. (II) U.S. Geological Survey, Flagstaff, AZ

Rosen, Phillip C. (I, II) University of Arizona, Tucson, AZ

Birds

Baltosser, William H. (*) University of Arkansas, Little Rock, AR

Block, William M. (I) U.S. Forest Service Rocky Mountain Research Station, Flagstaff, AZ

Bock, Carl E. (I) University of Colorado, Boulder, CO

Boren, Jon C. (I, *) New Mexico State University, Las Cruces, NM

Cartron, Jean-Luc E. (II) University of New Mexico, Albuquerque, NM

Cox, Steven W. (II) Private consultant, Albuquerque, NM

Cox, Nancy S. (I, II) Private consultant, Albuquerque, NM

Evans, Jules G. (*) Private consultant, Point Reyes Station, CA

Gall, Sally A. (*) U.S. Fish and Wildife Service, Buenos Aires NWR

Howe, William H. (II) U.S. Fish and Wildife Service, Albuquerque, NM

Johnson, Kris (*) New Mexico Natural Heritage Program, Albuquerque, NM

Johnson, R. Roy (I, II) Private consultant, Tucson, AZ

Kingsley, Kenneth J. (I) Private consultant, Flagstaff, AZ

Krueper, David J. (II) Bureau of Land Management, Sierra Vista, AZ

Ligon, J. David (II) University of New Mexico, Albuquerque, NM

Meyer, Raymond (II) Private consultant, Las Cruces, NM

Ohmart, Robert D. (I) Arizona State University, Tempe, AZ

Rustay, Christopher H. (I, II) Hawks Aloft and Partners-In-Flight, Albuquerque, NM

Ruth, Janet M. (II) U.S. Geological Survey, Albuquerque, NM

Sheppard, Jay M. (*) U.S. Fish and Wildife Service (ret), Laurel, MD

Stacey, Peter B. (I, II) University of New Mexico, Albuquerque, NM

Stoleson, Scott H. (I, II) U.S. Forest Service Rocky Mountain Research Station, Albuquerque, NM

Taylor, John P. (II) U.S. Fish and Wildife Service, Bosque del Apache NWR

Thompson, Bruce (I) U.S. Geological Survey, Las Cruces, NM

Warrick, Gordon (II) U.S. Fish and Wildife Service, Bitter Lakes NWR

Williams, Sartor O., III (I) New Mexico Department of Game and Fish, Santa Fe, NM

Mammals

Boren, Jon C. (II) New Mexico State University, Las Cruces, NM

Brown, David E. (I) Arizona State University, Tempe, AZ

Cook, Roseanne (I) Colorado State University, Ft. Collins, CO

Cryan, Paul M. (*) U.S. Geological Survey, Albuquerque, NM

Ditto, Amy (I) University of New Mexico, Albuquerque, NM

Dragoo, Jerry W. (II) University of New Mexico, Albuquerque, NM

Findley, James S. (II) University of New Mexico (ret), Albuquerque, NM

Frey, Jennifer K. (I, II) Eastern New Mexico University, Portales, NM

Hakkila, Mark D. (*) Bureau of Land Management, Las Cruces, NM

Harrison, Robert L. (II) University of New Mexico, Albuquerque, NM

Hayward, Bruce J. (II) Western New Mexico University (ret), Silver City, NM

Howard, Volney W., Jr. (II) New Mexico State University (ret), Las Cruces, NM

Kingsley, Kenneth J. (I) Private consultant, Flagstaff, AZ

Koprowski, John L. (II) University of Arizona, Tucson, AZ

Shaw, Harley G. (II) Arizona Game and Fish Department (ret), Phoenix, AZ

Smith, Felisa A. (I, II) University of New Mexico, Albuquerque, NM

Snow, Timothy K. (*) Arizona Game and Fish Department, Phoenix, AZ

Parmenter, Robert R. (II) University of New Mexico, Albuquerque, NM

Vahle, Bob (I, II) Arizona Game and Fish Department, Phoenix, AZ

Appendix A—Grazing Assessment Panelists__________________________

The following is a list of the 49 participants in the grazing assessment panel process and their professional affiliations at the time of their

participation. Panelists from the first stage of the process are identified using a superscript (I); second stage panelists are also identified by a

superscript (II). Some individuals participated in both stages of the process (I, II). Those that participated under more than one taxonomic group

are listed separately under each. Individuals with an asterisk (*) participated as “outside reviewers” (see Methods: The Panel Process - Stage II),

providing reviews of species accounts by electronic or regular mail. For individual species, the specific panel members are listed at the end of

each account.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 45

Scientific Name: Scientific name

Common Name: Common Name

Legal Status:

• Arizona - WSCA • ESA - Warranted but Precluded • New Mexico - Threatened

• BLM, AZ - Sensitive • Migratory Bird Treaty Act • USFS Region 3 - Sensitive

• BLM, NM - Sensitive • Navajo - Endangered • None

• CITES - Appendix I • Navajo - Threatened

• CITES - Appendix II • New Mexico -Endangered

• ESA - Endangered

• ESA - Threatened

Distribution:

• Endemic to Arizona • Southern limit of distribution

• Endemic to Arizona and New Mexico • Eastern limit of distribution

• Endemic to New Mexico • Western limit of distribution

• Not restricted to Arizona or New Mexico • Very local

• Northern limit of distribution

Ecological Role:

• Commensal/mutualistic • Insectivore • Pollinator

• Granivore • Key prey species • Primary cavity nester

• Herbivore • Key vector • Scavenger/detritivore

• Hybridization/intergradation • Omnivore • Secondary cavity nester

• Key predator • Parasitic

Status/Trends/Threats: text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text--

---text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

Distribution: text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

KEY DISTRIBUTION/ABUNDANCE/MANAGEMENT AREAS: key areas

Breeding:text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-

----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

Habitat: text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text--text-----text-----text-----text-----text-----text-----

text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

text-----text-----text-----text-----text-----text-----text-----text-----text-----

LANDSCAPE-LEVEL HABITAT REQUIREMENTS: landscape-level requirements.

LANDSCAPE-LEVEL HABITAT REQUIREMENTS:

• Amount of edge:

• Connectivity between patches of suitable habitat:

• Patch size and distance to nearest suitable patch:

o If isolated patch:

o If patches connected via marginal habitat:

• Other comments:

Part of Life Cycle:

• Breeding

• Hibernation/estivation

• Migrating

• Wintering

Appendix B—Species Account Template _____________________________

The following is the basic template of the draft species account (see

text for further descriptions and definitions). All choices are shown

for each menu of ecological parameters from which the panelists

made selections appropriate to the individual species. Areas where

draft text would appear are indicated by (text---text---text---). Panel

comment boxes were used to make additional comments or alterations to the definition of menu choices; blank boxes do not appear in

the final version of an account.
46 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Season of Use: text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text--text-----text-----text-----text-----text-----

text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

text-----text-----

Season of Use:

• January • May • September

• February • June • October

• March • July • November

• April • August • December

Specific Habitat Associations:

• Alpine tundra • Interior chaparral • Sonoran/Mojavean Desert

• Boreal forest • Subalpine grasslands (includes • Chihuahuan Desert

• Mixed conifer (C) Festuca thurberi meadow) • Narrowleaf cottonwood

• Mixed conifer (M) • Montane meadow • Cold broadleaf cottonwood

• Ponderosa pine forest • Temperate grassland • Warm broadleaf cottonwood

• Madrean pine forest • Mesquite savanna • Riparian scrub

• Pinyon-juniper woodland • Great Basin sagebrush • Dry washes

• Madrean woodland shrubsteppe • Wetlands

• Great Basin juniper- • Shinnery oak/sand sage • Developed lands

sagebrush savanna • Great Basin temperate desert • Other

Panel comments: habitat associations

Important Habitat Functions for this Species:

• Berry production • Insect production • Reproductive cover

• Escape cover • Perches for hunting • Seed production

• Forage production • Perches not for hunting • Shade/thermal cover

• Hiding cover • Prey production • Water availability

Panel comments: important vegetation components

Important Structural Features of Habitat (By Vegetation Layer):

Trees/saguaros (height) Forb layer (height) Grass layer (height)

• Trees >10 m • Residual >1 m • Residual >1 m

• Trees 5-10 m • Residual 0.5-1 m • Residual 0.5-1 m

• Trees <5 m • Residual 0.25-0.5 m • Residual 0.25-0.5 m

• Mixed size trees • Residual 0.1-0.25 m • Residual 0.1-0.25 m

• Not important • Residual <0.1 m • Residual <0.1 m

• Unknown • Not important • Not important

• Variable • Unknown • Unknown

Shrub layer (height) • Variable • Variable

• Shrubs >2 m

• Shrubs 0.5-2 m

• Shrubs <0.5 m

• Not important

• Unknown

• Variable

Panel comments: vegetation height
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 47

Trees (canopy) Shrub layer (density) Herbaceous layer (density)

• Canopy cover >60% • Dense understory • Dense cover

• Canopy cover 40-59% • Intermediate understory • Intermediate cover

• Canopy cover 1-39% • Sparse understory • Sparse cover

• Canopy cover 0% • Shrubs absent • Bare ground

• Not important • Not important • Not important

• Unknown • Unknown • Unknown

• Variable • Variable • Variable

Panel comments: canopy cover and vegetation density

Trees/saguaros (distribution) Shrub (distribution) Grass/forbs (distribution)

• Scattered • Scattered • Clumps

• Clumps • Clumps • Even

• Even • Even • Not important

• Not important • Not important • Unknown

• Unknown • Unknown • Variable

• Variable • Variable

Panel comments: vegetation distribution

Trees/saguaros (age) Elevation

• Old growth • High >7,000 ft

• Mixed age stand • Low <7,000 ft

• Mature • All elevations

• Sapling/pole

• Young (seedling)

• Not important

• Unknown

• Variable

Panel comments: age and elevation

Other Important Habitat Features:

Body of water • Leaf litter • Sand dunes

• Acequias/ditches • Loam • Talus

• Backwaters • Mud • Not important

• Livestock tanks • Pebbles/gravel • Unknown

• Ponds/lakes • Rocks/boulders • Variable

• Pools, deep • Sand Tree-related features

• Pools, shallow • Soil for burrowing • Logs

• Riffles • Not important • Loose bark

• Seeps/saturated soil • Unknown • Snags

• Springs • Variable • Tree cavities

• Streams and rivers Topography • Not important

• Surface water • Arroyos • Unknown

• Tinajas • Bajadas Human structures

• Not important • Canyon bottoms, broad • Bridges

• Unknown • Canyon bottoms, narrow • Buildings

• Variable • Canyon slopes, gentle • Fences

Soil substrate/ground features • Canyon slopes, steep • Mines

• Bare ground • Caves • Utility poles

• Bedrock • Cliffs • Not important

• Brush/debris piles • Flats • Unknown

• Burrows • Floodplains • Variable

• Clay • Rolling hills

• Crevices

Panel comments: other habitat features
48 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Diet: text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text--

---text-----text-----text-----text-----text-----

Diet Items:

• Acorns • Dung • Livestock

• Amphibians • Earthworms • Mammals

• Aquatic invertebrates • Fish • Nectar/pollen

• Aquatic vegetation • Flowers • Pine nuts

• Arthropods • Forbs • Reptiles

• Bird eggs • Fruits (fleshy) • Rodents/rabbits

• Birds • Fungi • Roots

• Browse (tree and shrub) • Grass • Sap

• Butterflies/moths • Herp eggs • Seeds

• Carrion • Insect larvae • Trash/garbage

• Crops, agricultural • Insects • Vertebrates

• Invertebrates • Wild ungulates

Grazing Effects:text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text--

---text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

LIMITING HABITAT COMPONENT RELATIVE TO GRAZING: limiting habitat component

Is this species a priority for selecting a grazing strategy?

Throughout the species’ distribution in New Mexico and Arizona

YES NO UNKNOWN

In key management area(s)

YES NO UNKNOWN

Possible Grazing Impact Mechanisms:

• Alteration of soil structure • Change in water quality • Killing burrowing rodents

• Alteration of water regimes • Competition for forage • Other biotic factors

• Altered fire regime • Cowbird parasitism • Parasites or pathogens

• Altered vegetation composition • Habitat fragmentation • Population genetic structure loss

• Altered vegetation structure • Increased predation • Range improvements

• Change in prey/food availability • Intentional killing • Trampling, scratching

Panel comments: grazing impact mechanisms

Fire Regime Requirements:text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-

----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----text-----

Is fire regime critically important for this species?

YES NO UNKNOWN

If YES:

Frequency Intensity Timing

• High (1-10-year interval) • High (stand replacing) • Spring

• Intermediate (11-100-year interval) • Medium (affects shrubs) • Summer

• Low (>100-year interval) • Low (surface fire) • Fall

• None • None • Winter

• Unknown • Unknown • Never

• Unknown

References:

references

references

references

references

Authors/Panelists:

• Draft: draft author(s)

• GP 1999: panelists’ names

• GP 2001: panelists’ names

• Revision: revision author(s)
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 49

This list contains those resources that were repeatedly used

during the development of the species accounts and that are

believed to be some of the most useful sources of information

for individuals wishing to obtain further details on the species

of interest.

Grazing

Jemison, R.; Raish, C., eds. 2000. Livestock Management in

the American Southwest: Ecology, Society, and Economics. Amsterdam: Elsevier Science.

This publication by scientists with the U.S. Department of

Agriculture, Forest Service, Rocky Mountain Research Station (Albuquerque), and their scientific colleagues not only

examines livestock interactions with specific ecosystems (for

example, range grasslands, riparian areas, and so forth), but

also provides chapters on land use history, grazing systems,

and the economic, social, and cultural aspects of the ranching

industry in the Southwest.

Krausman, P. R., ed. 1996. Rangeland wildlife. Denver, CO:

Society for Range Management.

This compilation by the Society for Range Management

presents information on the major vertebrate species in the

Western United States and their interactions with livestock.

Presented from a management perspective, the document

contains chapters on a variety of taxa by experts on those

species, as well as information pertaining to management

issues (manipulation of plants, prescribed fire, range improvements, diseases, and so forth) and a section on political and

economic issues.

Herpetofauna

Degenhardt, W. G.; Painter, C. W.; Price, A. H. 1996. Amphibians and reptiles of New Mexico. Albuquerque: University of New Mexico Press.

A thorough and authoritative compilation of the herpetofauna

of New Mexico, including information on basic biology,

ecology, distribution, and natural history. Distribution maps

and color photographs are included; many of these species also

are known to occur in Arizona.

Birds

Arizona Game and Fish Department (AGFD). 1988. Threatened native wildlife in Arizona. Publication. Phoenix, AZ:

Arizona Game and Fish Department.

This publication was the last list of species officially approved

by the Arizona Game and Fish Commission for legal designation. This publication breaks down the species into categories of

endangered, threatened, or candidate species, but action by the

Appendix C—Annotated Bibliography of Major Information Sources ______

commission since then has eliminated these categories in favor

of a single designation WSCA, or Wildlife of Special Concern

in Arizona (Schwarz, personal communication).

Bent, A. C. (Various years). Life histories of North American

[birds]. Bulletin [various]. Washington, DC: U.S. National

Museum.

These bulletins form a classic collection of detailed species

accounts written or edited by Arthur C. Bent. Compiled primarily in the mid 20th century, these bulletins present detailed

descriptions of the various species’ ecology and natural history. While superceded in many instances by information

published in “Birds of North America” (see below), these

bulletins remain the primary source for many aspects of basic

biology and ecology. As with other historical sources listed

here, they also provide a window into habitat conditions

present at an earlier time.

Hubbard, J. P. 1978. Revised check-list of the birds of New

Mexico. Publication No. 6. Albuquerque, NM: New Mexico

Ornithological Society.

A review of all species known to occur in New Mexico, with

notes on distribution, specimen records, seasonal occurrence,

and habitat affiliations. Users should contact the New Mexico

Ornithological Society for further updates or revisions of this

publication.

Monson, G.; Phillips, A. R. 1981. Annotated checklist of the

birds of Arizona, second edition. Tucson, AZ: University

of Arizona Press.

An update to the more detailed accounts of Phillips and

others (1964) (see below), this publication contains a review of

all species known to occur in Arizona, with notes on distribution, seasonal occurrence, and habitat affiliations.

Phillips, A.; Marshall, J.; Monson, G. 1964. The birds of

Arizona. Tucson, AZ: University of Arizona Press.

A collection of thorough accounts of all birds known to occur

in Arizona. Although somewhat dated, this publication presents

an authoritative review of the distribution, specimen records,

seasonal occurrence, and habitat affiliations of these species.

Poole, A.; Gill, F., eds. (Various years). The birds of North

America. Philadelphia, PA: The Birds of North America,

Inc. (Species list available on-line at: www.birdsofna.org).

An ambitious project started by the American Ornithologists’

Union and the American Museum of Natural History in Philadelphia to create the most detailed species accounts available of

all birds known to occur in North America and the Hawaiian

islands. Carried by most university libraries, these accounts are

considered to be the most complete compilation of all research

and information available for each species covered, and they

should be the starting point for anyone looking to compile

additional information on individual species.
50 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Sauer, J. R.; Hines, J. E.; Fallon, J. 2001. The North American

Breeding Bird Survey, results and analysis 1966-2000

(version 2001.2)[Online]. Laurel, MD: U.S. Department of

Interior, Geological Survey, Patuxent Wildlife Research

Center. Available: http://www.mbr-pwrc.usgs.gov/bbs/

bbs00.html [2003, August 12].

This Web site provides complete documentation and opportunities for analysis of Breeding Bird Survey information

across all areas covered and for all years of its operation, down

to the level of individual survey routes. The site also contains

complete information regarding data collection protocols and

the assumptions and cautions involved in the different statistical analyses.

Mammals

American Society of Mammalogists. Various years.Mammalian Species Accounts. [Online]. Available: www.science.

smith.edu/departments/Biology/VHAYSSEN/msi/ (2003

November 20).

Another ambitious species account project analogous to the

Birds of North America, but designed to eventually cover all

species of mammals throughout the world. Detailed accounts

have been written for many North American species, and most

can be downloaded at the above Web address. Because of the

global nature of this project, not all North American species

have had accounts published.

Bailey, V. 1932. Mammals of New Mexico. North American

Fauna No. 53. Washington, DC: U.S. Department of Agriculture, Bureau of Biological Survey.

A classic collection of detailed species accounts from early

20th century New Mexico. As with the Bent series on birds (see

above), much of this information may be dated, but the basic

biology is sound and it gives insight into ecological conditions

from almost a century ago.

Findley, J. S.; Harris, A. H.; Wilson, D. E.; Jones, C. 1975.

Mammals of New Mexico. Albuquerque, NM: University

of New Mexico Press.

An authoritative account of the all the various mammals

known to occur in New Mexico. Includes detailed information

on taxonomy, distribution, specimen records, ecology, and life

history.

Hoffmeister, D. F. 1986. Mammals of Arizona. Tucson, AZ:

University of Arizona Press.

An authoritative account of the all the various mammals

known to occur in Arizona. Includes detailed information on

taxonomy and species identification, but also distribution,

ecology, and life history.

Demarais, S.; Krausman, P. R.; eds. 2000. Ecology and

management of large mammals in North America. Upper

Saddle River, NJ: Prentice-Hall Inc.

An extensive textbook on large mammal management, with

thorough coverage of issues pertaining to many species in this

database including elk, deer, bear, predatory cats, wild sheep,

and more. Chapters are written by research scientists and are

thoroughly researched and documented by references from the

latest scientific literature.

Internet Web Sites

Arizona Game and Fish Department (AGFD). (2004, September 2—last update). Arizona Game and Fish [Homepage of

Arizona Game and Fish Department], [Online]. Available:

http://www.gf.state.az.us/ [2004, September 6].

Online resources for species information and state regulations.

New Mexico Department of Game and Fish (NMDGF). (2004,

August 19—last update). New Mexico Wildlife [Homepage

of New Mexico Department of Game and Fish], [Online].

Available: http://www.wildlife.state.nm.us/ [2004, September 6].

Online resources for species information and State regulations. Particularly useful are downloadable copies of the biennial reviews of threatened and endangered species of New

Mexico.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 51

This annotated list documents the species that were selected

for inclusion by the Stage I panel process, but then subsequently removed after further consideration in Stage II. Readers should keep in mind that the Stage II panels were frequently

staffed by different panelists, especially among the major

vertebrate taxa (herpetofauna, birds, and mammals). The panelists may have determined that grazing more frequently

benefits a species, or that the negative impact on a species is

insignificant or unlikely to occur. It is important to recognize

that the decision to remove a species was not necessarily a

unanimous one; nor does it indicate an unequivocal conclusion

on the part of those who agreed to remove it. In fact, the

publication of this appendix was often a critical factor for the

panelists when deciding to remove a species. Panelists considered probability as well as possibility within the larger goal of

focusing on the species with the greatest likelihood of being

negatively impacted. Thus, each decision represents a general

consensus of the panel within these guidelines, and users

should not conclude that these species cannot be or are never

affected negatively by grazing or range management practices.

We recommend that all users review this list and the annotated

information to determine if any conditions that can lead to

negative impacts are likely to occur.

The descriptions below present information on the geographic range and ecology of each species, with some discussion of potential grazing impacts (or lack thereof). Species are

organized into three groups (Herpetofauna, Birds, and Mammals), and are then listed in taxonomical order as determined

by the respective authorities (for example, AOU 1998 for

birds).

Herpetofauna

Gilbert’s Skink (Eumeces gilberti): The database includes

one subspecies of E. gilberti, the Arizona skink (E. g.

arizonensis). The other subspecies are almost all endemic to

California, with some populations of the western red-tailed

skink (E. g. rubricaudatus) occurring in southern Nevada and

northern Baja California, Mexico. Gilbert’s skink (as a species) was rejected to restrict the database to the one subspecies

from Arizona.

Desert Grassland Whiptail (Cnemidophorus uniparens): A

Chihuahuan Desert species of southeastern Arizona and southwestern New Mexico, up into the central Rio Grande valley. It

is common in desert grassland habitats, as well as grasslands

that have been degraded, thus allowing the expansion of shrubs

(Degenhardt and others1996). Other species of Cnemidophorus

included in this database generally require well-developed

grassland habitat, and any degradation of grasslands, especially leading to shrub encroachment, will benefit the desert

grassland whiptail in competitive interactions (GP 1999a,

2000a). It is believed that overgrazing and increased desertification of grasslands and riparian areas has actually contributed

Appendix D—Species Removed by Stage II Panels ____________________

to the expansion of this species’ range in New Mexico

(Degenhardt and others1996).

Birds

Little Blue Heron (Egretta caerulea): In the United States,

this species occupies breeding grounds primarily in the Southeast (AOU 1998); it summers irregularly in New Mexico

(Hubbard 1978). Its occurrence here is not considered to be

significant enough to be affected by grazing or range management practices (GP 2001k).

California Condor (Gymnogyps californicus): As of August

2002, this endangered species numbered 206 birds in four

subpopulations: 113 in captivity (in Los Angeles, CA; San

Diego, CA; Boise, ID; soon to include Oregon) and the rest in

reintroduced wild populations in California (50), Arizona (37),

and Baja California, Mexico (6) (Ralls and Ballou 2004). The

California condor once occupied a range extending from

Canada south through the Western United States to Baja

California, and fossils have been recovered as far east as New

York and Florida (Snyder and Rea 1998; Terres 1996). Birds

released in Arizona are currently located north of the Grand

Canyon (Snyder and Rea 1998). The Grazing Panel (2001a)

determined that condors experience both positive and negative

impacts resulting from the presence of grazing operations.

However, while ultimately deciding to remove this species, the

panel also felt that it is important to address the role of grazing

management and the grazing industry in the protection and

perpetuation of the species. Condors in the wild, as scavengers

of dead carcasses, are attracted to cattle as a potential source of

food (Snyder and Rea 1998); a positive effect could result from

the presence of cattle in its range, assuming that dead cattle are

not removed from the range. However, fencing, poisoning for

coyotes (resulting in poisoned carrion), and incidental shooting all have the potential for negative impacts (with the

understanding that these activities can occur even without

grazing).

Canada Goose (Branta canadensis): A common, widespread

species, the Canada goose has increased tremendously over the

past three decades and is one of the success stories for wildlife

management (Bellrose 1980). In Arizona, the Canada goose

winters commonly to abundantly in southwestern and central

Arizona and along the Virgin River (Monson and Phillips

1981). In New Mexico, the Canada goose is resident locally in

the northern portion of the State and southward in the Rio

Grande and Pecos valleys; it migrates and winters almost

Statewide (Hubbard 1978). There is no indication that grazing

has negative impacts on this species; in addition, these geese

are known to frequent (and even breed) in artificial water

habitats in urban environments (GP 2001l).

Mallard (Anas platyrhynchos platyrhynchos): The mallard

is probably the most recognized species of duck in the Northern

Hemisphere, especially the subspecies A. p. platyrhynchos
52 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

because it is the most abundant (Bellrose 1980). In Arizona, the

mallard is both a transient and a winter resident wherever there

is open water. It breeds on high mountain lakes in the northern

part of the State, as well as locally in the lower Colorado

Valley, and formerly near Phoenix and elsewhere (Monson

and Phillips 1981). In New Mexico, the mallard is resident in

the northeast (east to Clayton, where it breeds) and from the

Pecos Valley westward; it migrates and winters Statewide in

suitable habitats (Hubbard 1978). Mallards breed near any type

of fresh water, in a variety of habitats (Bellrose 1980). Pastures

and stock tanks can be positive during migration and winter;

however, reduced vegetation due to grazing can have negative

impacts on this species. Reduced herbaceous cover increases

the risk of predation on nesting females in the breeding season

(GP 1999d). This species is common in the Southwest and

widespread and abundant throughout North America; it is

unlikely to be significantly impacted by grazing or range

management practices conducted in the Southwest (GP 2001m).

Mexican Duck (Anas platyrhynchos diazi): Once considered

a separate species, the Mexican duck is now considered a

subspecies of the mallard by the American Ornithologists’

Union (AOU 1998). Hubbard (1977) estimated that the total

population in the United States to be 650 to 900; 200 to 300 for

New Mexico, 150 to 200 for Arizona and 300 to 400 for Texas.

In Arizona, the Mexican duck is locally resident in the southeastern portion of the State (Monson and Phillips 1981; Phillips

and others 1964). In New Mexico, the Mexican duck is rare due

to hybridization with the mallard (A. p. platyrhynchos). Hybrid

forms are resident in the Southwest, south of the Mogollon

Plateau, and in the lower and middle Rio Grande Valley

northward to Bosque Del Apache National Wildlife Refuge

(Hubbard 1978). Hubbard (1977) reported that grazing, burning, and other factors might reduce nesting cover by late spring

to the point that breeding is delayed in some regions. Aldrich

and Baer (1970 as cited in Bellrose 1980) reported that disturbance of the Mexican duck’s habitat by people (for example,

conversion of wetlands to cropland and rangeland) and livestock is so extensive that its survival is probably in jeopardy.

The Grazing Panel (2001m) believed that, in the Southwest, it

is unlikely to be significantly impacted by grazing or range

management practices and instead is more likely to be jeopardized by continued hybridization with the mallard.

Blue-Winged Teal (Anas discors): The blue-winged teal is a

common duck throughout the United States; however, in the

West it is generally replaced by cinnamon teal (Bellrose 1980).

It breeds from southern Canada down through California, New

Mexico, Texas, and Louisiana with breeding densities highest

in the prairie pothole region (Bellrose 1980; Johnsgard 1975).

In Arizona, blue-winged teal are transients throughout the

State in spring and fall, with numbers and dates variable from

year to year (Monson and Phillips 1981). In New Mexico, bluewinged teal have been recorded breeding at Burford Lake and

at Bosque del Apache and Bitter Lake National Wildlife

Refuges. This species migrates and summers almost Statewide

and is irregular in winter in the Rio Grande and Pecos valleys,

casual to occasional elsewhere (Hubbard 1978). The bluewinged teal is at the southern edge of its breeding range in New

Mexico and generally winters outside of the Southwest. Thus,

relative to other ducks, it is less likely to be impacted by grazing

or range management practices in the Southwest (GP 2001l).

Hooded Merganser (Lophodytes cucullatus): The hooded

merganser is split into eastern and western populations that are

seemingly isolated from one another (Johnsgard 1975). Hooded

mergansers breed throughout the east and Pacific Northwest

but most commonly in forested regions around the Great

Lakes. In Western North America, they breed as far north as

southeastern Alaska (Bellrose 1980). Monson and Phillips

(1981) reported the hooded merganser as a winter resident in

small numbers in southern Arizona, principally in the lower

Colorado Valley above Parker Dam. In New Mexico, hooded

mergansers migrate and winter almost Statewide, being rare to

uncommon and local; unverified breeding records on the upper

Pecos River are doubtful (Hubbard 1978). Due to the lack of

breeding in the Southwest and its generally rare to uncommon

occurrence there, it is not likely to be impacted by grazing or

range management practices (GP 2001k).

Gray Hawk (Asturina nitida): The gray hawk is at the

northern limit of its distribution in Arizona, New Mexico, and

Texas (Russell and Monson 1998). In the Uunited States, the

largest population of gray hawks is in Arizona, but the species

appears to be increasing in numbers in Texas (Glinski 1998).

In New Mexico, the gray hawk may be essentially an accidental breeder (GP 1999d). Throughout the Southwest, the gray

hawk usually nests in tall cottonwood trees along permanent

streams (Glinski 1998; Ligon 1961; Russell and Monson

1998). Thus, overgrazing in riparian areas may impact the

recruitment of these and other large deciduous trees used for

nesting.

American Kestrel (Falco sparverius): This is a small, common, and widespread falcon that breeds throughout the United

States and Canada and occurs year-round in Arizona and New

Mexico. Generally associated with open areas, they are found

in a variety of habitat types (grassland, desert scrub, woodland,

and forests) (Mills 1998). Heavy grazing may impact prey

availability and, in riparian areas, may affect the recruitment of

large trees for nest cavities (GP 1999d). However, results from

various studies on the impact of grazing on kestrels have been

mixed (see Saab and others1995), and the panel (GP 1999d)

did not believe it to be negatively impacting the species in the

Southwest.

Gambel’s Quail (Callipepla gambelii): The center of the

distribution of Gambel’s quail is in Arizona and northwestern

Sonora, Mexico; this distribution extends into all adjacent

States. Gambel’s quail is common in desert mountain foothills

and wash-laced plains within several vegetative communities

of the Southwest. These include the Upland subdivision of the

Sonoran Desert, shrubbier and wetter portions of the Mojave

Desert, scrub-invaded semidesert grassland, and open interior

chaparral in southern and western Arizona (Brown 1989).

Some of the best areas for Gambel’s quail include scrubinfested grasslands (Brown and others 1998). It is not believed

to be as sensitive to grazing as other quail species. However,
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 53

heavy livestock grazing and shrub removal could potentially

impact this species’ habitat requirements, which include a

shrub component in grasslands as well as sufficient grasses and

forbs to produce a standing seed crop (GP 1999b).

American Coot (Fulica americana): This species is widespread and relatively common throughout North America. In

Arizona, the American coot is a common summer resident and

winters throughout the State in open water, especially along

the lower Colorado River (Phillips and others 1964). In New

Mexico, it is resident almost Statewide and is most widespread

during migration, except on the eastern plains (Hubbard 1978).

While the Stage I panel (GP 1999d) recognized that this species

could potentially be impacted locally by the loss of emergent

vegetation used for nesting cover, the Stage II panel (GP

2001k) noted that it appears highly resilient to habitat degradation. The panel ultimately decided that it was unlikely that

grazing operations in the Southwest would severly impact this

species, based on its general abundance and its occurrence in

degraded wetlands as well as artificial water sources.

Anna’s Hummingbird (Calypte anna): This hummingbird

breeds from southern Arizona north through California (west

of the Sierra Nevada range) to British Columbia, Canada.

Breeding range in Arizona spans the area south of Phoenix and

continues north along the Colorado River. Summer records

include southern New Mexico and west Texas (AOU 1998).In

breeding sites in Arizona, this species is highly dependent on

the flowering of plants in the chaparral of the Upper Sonoran

zone, which occurs with the onset of winter rains (Stiles 1973).

In addition, during the postbreeding movements to the east and

southeast out of California, Anna’s hummingbird highly depends on the blossoming of flowering plants tied to seasonal

rainfalls (mid to late summer). Although the effect was not

thought to be severe (GP 2000d), grazing activities could

negatively impact this species if these food resources were

degraded; fence lines and roadsides that encourage the growth

of flowering forbs may be a benefit (GP 1999c).

Calliope Hummingbird (Stellula calliope): This bird breeds

in montane environments of the Western United States and

Southwestern Canada. It occurs in Arizona and New Mexico as

a fall south-bound migrant, mimicking the “oval racetrack”

pattern of the rufous hummingbird: north-bound in spring

along the Pacific Coast, south-bound in fall via the Rocky

Mountains (Phillips 1975). Grazing that degrades the flowering plants in high-altitude alpine and sub-alpine meadows that

are utilized for food resources during this migration could

potentially affect this species (GP 1999c). However, the likelihood of any severe negative impacts from grazing was

thought to be low (GP 2000d).

Rufous Hummingbird (Selasphorus rufus): This hummingbird occurs in the Southwest almost exclusively in migration.

In the spring, it may pass through southwestern Arizona along

its West Coast route. In fall, it follows the Sierra Nevada and

Rocky Mountains south into Mexico. Flowering plants in

montane meadows and high-altitude disturbed habitats are

utilized for food resources during this migratory trek (Calder

1993). Grazing in these high-altitude meadows may impact the

availability of flowering plants (GP 1999b), but overall the

status of this species is not likely to be impacted by grazing in

the Southwest (GP 2000b).

Allen’s Hummingbird (Selasphorus sasin): Breeds along a

narrow strip of the California coast, from Ventura County into

extreme southwestern Oregon (AOU 1998; Mitchell 2000). Its

northward migratory path tends to track the Pacific Coast,

while the southbound migration is more inland, along interior

mountain ranges (Mitchell 2000); in migration it occurs east,

at least casually, to southern Arizona and New Mexico (AOU

1998). Its occasional occurrence in the Southwest is not

considered to be significant enough to be affected by grazing

or range management practices (GP 2000d).

American Three-Toed Woodpecker (Picoides dorsalis):

Formerly classified as P. tridactylus(Banks and others 2003).

A resident of coniferous forests across Canada to Alaska and

south into the Rocky Mountains; Arizona and New Mexico

represent the southern edge of its range (Leonard 2001). Many

woodpeckers and other woodland birds are listed in this

database because of concern for the long-term potential of

grazing in forest areas (particularly ponderosa pine) to remove

grass cover that carries low-intensity fires, thus encouraging

growth of dog-hair thickets of small pine trees and increasing

the threat of catastrophic fire. However, the three-toed woodpecker is a specialist of recently burned-over forest and is one

of the first species to invade after a forest fire (Leonard 2001),

and thus it could be positively affected by these mechanisms.

Pacific-Slope Flycatcher (Empidonax difficilis): This species, formerly a race of the western flycatcher, breeds west of

the Sierra Nevada and Cascade ranges (AOU 1998). It occurs

as a migrant in the Southwest and also along the lower

Colorado River as a wintering bird (Rosenberg and others

1991). Because the Pacific-slope flycatcher depends on lush

riparian foraging areas while migrating, the loss of such

vegetation would have a negative impact on this species

(GP1999d). However, its occurrence in the Southwest is not

considered to be significant enough to be affected by grazing

or range management practices in the region (GP 2001k).

Dusky-Capped Flycatcher (Myiarchus tuberculifer): This

species is at the northern limit of its distribution in Arizona and

New Mexico (AOU 1998). In Arizona, the dusky-capped

flycatcher occurs as a summer resident in mountain ranges

from Guadadalupe Canyon in the extreme southeastern corner

of the State, west to the Baboquivari Mountains and north to the

Pinal and Pinaleno Mountains (Monson and Phillips 1981). In

New Mexico, the species breeds in the Animas Mountains and

in Guadalupe Canyon (Hubbard 1987; Zimmerman and others

1992). In the Southwestern United States, the dusky-capped

flycatcher is usually found in dense hillside thickets of live

oaks and shady riparian areas with large trees, especially

sycamores (Bent 1942; GP 1999d; Monson and Phillips 1981;

Phillips and others 1964). Because it probably does not show

a preference for sycamores and/or other riparian vegetation

(typically occurring farther upland), it is not as likely to be

affected by grazing in this habitat as other, riparian-obligate

species of birds (GP 2001k).
54 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Tree Swallow (Tachycineta bicolor): Its breeding range includes much of northern and central North America from the

East Coast to the West Coast, and it winters from southern

California, southwestern Arizona, the Gulf of Mexico Coast,

and Florida south through Mexico and Central America to

Northern South America (Robertson and others 1992). Typical

habitat for the tree swallow over its entire range includes open

areas usually near water, with snags nearby for nesting in the

summer or wooded areas for roosting during the winter. In the

Southwest, tree swallows are associated with bodies of water,

wetlands, agricultural fields near riparian areas, aspen stands,

and wet meadows (Brown and others 1987; Ligon 1961;

Robertson and others 1992; Rosenberg and others 1991).

Where tree swallows nest near water, they may be negatively

affected by grazing through the loss of recruitment of riparian

nest trees (see Cartron and others 2000). Changes in fire

regimes and browsing in montane forests may adversely impact aspen stands and thus reduce the availability of nesting

habitat; however, this was not believed to be significant

enough to severly impact this species (GP 1999c).

Bank Swallow (Riparia riparia): The bank swallow is one of

the most widely distributed swallows in the world, with a

Holarctic breeding distribution (Garrison 1999). In Arizona, it

is a fairly common to rare migrant throughout the State

(Phillips and others 1964), whereas in New Mexico, it summers locally in the north and southward through the lower Rio

Grande and occasionally the lower Pecos River valleys

(Hubbard 1978). The bank swallow breeds mostly in lowland

areas along rivers, streams, lakes, reservoirs, and wetlands; it

burrows its nest in alluvial and friable soils (mostly sandy,

silty, or loamy) in vertical banks, cliffs, and bluffs (Garrison

1999). In some situations, large densities of ungulates could

potentially impact breeding sites by causing erosion of streamside banks. It was ultimately decided that this factor was not

likely to have a significant negative impact on this species (GP

2001k).

Barn Swallow (Hirundo rustica): The barn swallow is the

most widely distributed swallow in the world. In the Southwest, it breeds throughout New Mexico and eastern Arizona.

Overall, human activity (largely human-made structures providing nesting habitat) has had strongly positive effects on this

species, and currently no human activities are considered to

pose serious threats to this species (Brown and Brown 1999).

Barn swallows could be locally affected by grazing if water

regimes are altered enough to destroy water sources, drying up

the source of mud for nesting and insects for foraging (GP

1999b). However, overall, this species appears to be increasing

and is unlikely to be impacted by grazing (GP 2000b).

Verdin (Auriparus flaviceps): The verdin is at the northern

limit of its distribution in the Southwest. It ranges from

southeastern California, southern Nevada, southwestern Utah,

western and southern Arizona, southern New Mexico, and

Texas south to southern Baja California and central Mexico

(Terres 1996). In the Southwest the verdin occupies mesquite

bosques, cottonwood-willow woodlands, xeroriparian vegetation, and desert scrub (Bent 1946; Ligon 1961; Phillips and

others 1964; Rosenberg and others 1991). Its general preferred

habitat appears to be bosques of honey mesquite. It may also

occur in areas inhabited by humans and is found, at low

elevation, in salt cedar (Rosenberg and others 1991). The

verdin may be negatively affected where mesquite bosques are

cleared for rangeland (GP 1999d).

Cactus Wren (Campylorhynchus brunneicapillus): The cactus wren is a bird of Southwestern desert scrub; in the United

States it is found from central Texas across central and southern New Mexico and Arizona into southern Nevada and

southern California. Cactus wrens are found in areas of desert

scrub that are dominated by spinescent vegetation; that is,

thorny shrubs, trees, and cacti (Anderson and Anderson 1973;

Woods 1948). Cholla cactus appears to be particularly reliable

indicators of good cactus wren habitat (Woods 1948). Lloyd

and others (1998) found that cactus wren abundance declined

in an Arizona grassland as mesquite density increased, a

change they attributed to the absence of cholla cacti in the areas

with high densities of mesquite. Whereas the clearing of cactus

and desert scrub for rangeland would negatively impact this

species, it is likely that grazing has historically promoted

encroachment of cholla and other shrubs into grasslands to the

benefit of this species (GP 1999b, 2000b).

Winter Wren (Troglodytes troglodytes): The winter wren is

a breeding bird of the densest northern coniferous forests,

typically encountered there only in limited numbers (Bent

1948). In Arizona, this species is considered a local and rare

winter resident of permanent streams in the Transition Zone

and adjacent zones (Phillips and others 1964). In southern New

Mexico, it can occur both in winter and migration (Hubbard

1978). Throughout the Southwest, the winter wren is rare and

highly irregular, with unpredictable occurrences in both time

and locality. Thus, it is unlikely to be affected by grazing or any

range management practices (GP 2001k).

Veery (Catharus fuscescens): This bird breeds across the

length of the Canada-United States border, with the exception

of the far West Coast; it is an isolated breeder in Arizona and

an unrecorded but suspected breeding bird of New Mexico.

The veery has a strong affiliation with damp, deciduous

forests, with a preference for riparian areas in many regions.

Across its breeding range, the veery’s habitat selection may

depend on the presence of other thrushes, preferring deciduous

forest but moving into coniferous and mixed forests when

sharing breeding grounds (Moskoff 1995). The veery is believed to be impacted negatively by grazing due its groundnesting habits and the loss of brush and understory in riparian

woodlands (GP 1999d). However, the Southwest may be

outside the southern extent of its range; it no longer breeds in

the area around Springerville, AZ, and there are no documented breeding records in New Mexico. Therefore its occurrence is not considered to be significant enough to be affected

by grazing or range management practices in the region (GP

2001n).

Brown Thrasher (Toxostoma rufum): The brown thrasher is

a common species of Eastern North America, from the Rocky

Mountains east to the Atlantic Coast (Terres 1996). It inhabits
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 55

shrubland/woodland and residential areas at lower elevations

(Hubbard 1978). In Arizona, the brown thrasher is a rare fall

and winter migrant or vagrant to the Sonoran Zones of the

southeastern part of the State (Phillips and others 1964). In

New Mexico, it has been recorded east of the Rio Grande

Valley (Ligon 1961). This species summers occasionally and

locally in the east and casually farther west, and it migrates and

winters irregularly almost Statewide (Hubbard 1978). Its occurrence in the Southwest is not considered to be significant

enough for the species to be affected by grazing or range

management practices in this region (GP 2000f).

Bendire’s Thrasher (Toxostoma bendirei): This species is

widespread throughout the Southwestern United States and

Northwestern Mexico. This bird is common in open grassland

or shrubland with scattered shrubs or trees and in sagebrush

habitats with scattered junipers. In southern Arizona and New

Mexico, this species also breeds in degraded desert-grassland

and desert scrubland with various xerophytic and microphyllous shrubs and little grass cover (England and Laudenslayer

1993). Long-term grazing effects may be positive, and this

species is believed to generally respond positively to grazing

(GP 2001a). In New Mexico, the range of the Bendire’s

thrasher may have expanded due to overgrazing, which has

increased areas with scattered junipers (Darling 1970). It

should be noted that in California the loss of Joshua trees and

other yuccas to overgrazing has been suggested as potential

threats to local populations (Remsen 1978 as cited in England

and Laudenslayer 1993).

Cedar Waxwing (Bombycilla cedrorum): The cedar

waxwing’s breeding range is across the northern portion of

North America, from southeastern Alaska across Canada and

in the Northern United States (Terres 1996). It rarely breeds as

far south as portions of New Mexico (GP 1999d). It is a migrant

and an erratic winter visitor in Arizona (Phillips and others

1964), and a common migrant and winter visitor in New

Mexico (GP 1999d). The cedar waxwing depends on riparian

habitat, and any activity that decreases this habitat is likely to

reduce population numbers, especially the loss of berry-producing shrubs and trees for foraging and nesting, and the loss

of substrates for mistletoe (GP 1999d). However, this species

is so widespread across North America that activities in the

Southwest would likely have little if any impact (GP 2001n).

Nashville Warbler (Vermivora ruficapilla): A common migrant and summer resident of lower deciduous brush in the

higher mountains of Arizona (Monson and Phillips 1981) and,

locally, a fairly common migrant Statewide in New Mexico

(Hubbard 1978). However, its breeding and wintering range is

almost exclusively outside of the Southwest; thus, grazing

activity in the Southwest is likely to have little if any impact on

this species (GP 2001n).

Northern Parula (Parula americana): In Arizona, the northern parula is a rare spring, fall, and winter visitor in the southern

part of the State, with several records from the Tucson area

(Phillips and others 1964). In New Mexico, this species is a

casual summer visitor. It migrates irregularly in the east, west

to the Rio Grande Valley, and in the extreme southwest

(Hubbard 1978). As an irregular, uncommon migrant, its

occurrence in the Southwest is not considered to be significant

enough to be affected by grazing or range management practices in the region (GP 2001n).

Yellow-Rumped Warbler (Dendroica coronata): The yellow-rumped warbler is generally described as abundant

rangewide and is considered the most common wood warbler

in Canada (Ehrlich and others 1988; Terres 1996). Ligon

(1961) described it as one of the most abundant warblers in

New Mexico during its breeding season. In Arizona the yellow-rumped warbler is considererd common during the nesting season, in migration, and in the winter (Monson and

Phillips 1981). Several studies of grazing effects on birds

indicate a mixed response of this species to grazing, but

without statistical significance in any case (see Saab and others

1995). Given the widespread distribution of this species across

North America, activities in the Southwest would likely have

little if any impact (GP 2001n).

Townsend’s Warbler (Dendroica townsendi): This species

breeds in the Northwestern United States, north to southeastern

Alaska. It is a fairly common migrant through Arizona and

New Mexico, particularly at higher elevations (Hubbard 1978;

Phillips and others 1964). It irregularly occurs during winter in

southeastern Arizona (Monson and Phillips 1981). Townsend’s

warbler could potentially be affected by grazing regimes in the

Southwest that degrade dense riparian midstory and understory vegetation used as stopover foraging habitat, but any

effect is unlikely to be severe (GP 1999d).

Black-and-White Warbler (Mniotilta varia): This species

occurs in the Southwest only as a rare visitor in migration, with

its main migration taking place outside of the Southwest. Thus,

grazing activity here is likely to have little if any impact on this

species (GP 2001n).

American Redstart (Setophaga ruticilla): This species occurs in the Southwest only as a rare visitor in migration, with

its main migration taking place outside of the Southwest. Thus,

grazing activity in the region is likely to have little if any impact

on this species (GP 2001n).

Ovenbird (Seiurus aurocapilla): This species occurs in the

Southwest only as a vagrant in migration, with its main

migration route east of New Mexico. Thus, grazing activity in

the Southwest is likely to have little if any impact on this

species (GP 2001n).

Northern Waterthrush (Seiurus noveboracensis): This species occurs in the Southwest as a rare to uncommon migrant,

with most of its migration route east of New Mexico. Thus,

grazing activity in the Southwest is likely to have little if any

impact on this species (GP 2001n).

Hooded Warbler (Wilsonia citrina): This species occurs in

the Southwest only as a rare vagrant in migration, with its main

route well east of New Mexico. Thus, grazing activity in the

Southwest is likely to have little if any impact on this species

(GP 2001n).

Red-Faced Warbler (Cardellina rubifrons): The red-faced

warbler reaches the northern edge of its breeding distribution

in the Southwestern United States (Martin and Barber 1995).
56 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

In Arizona, this species is described as a common summer

resident of montane forests (Phillips and others 1964). In New

Mexico, it is considered as an uncommon to common summer

resident (Hubbard 1978; Ligon 1961). It is most common in

pine-fir or fir forests, often along streams or low on canyon

slopes, where mesic conditions are prevalent; it is also present

in pine and pine-oak forests (Ligon 1961; Martin and Barber

1995; Monson and Phillips 1981; Phillips and others 1964).

Red-faced warblers nest on the ground, often on the banks of

montane drainages. In this habitat, they are susceptible to

trampling of nests and vegetation serving as reproductive

cover. They may also be negatively affected by ungulate

overgrazing leading to the loss of cool, damp, and shady

conditions (GP 1999d). The Stage II panel (GP 2001n) noted

that, because the red-faced warbler tends to prefer the steeper

montane slopes, cattle are unlikely to impact it in these areas.

Canyon Towhee (Pipilo fuscus): This species is relatively

common in mountain foothills and lower canyons throughout

the Southwest, associated with brushlands, arid scrub, mesquite, riparian thickets, and human habitations (AOU 1998;

Terres 1996). Severe overgrazing would likely be detrimental

through the removal of grasses (seeds) used for food and grass

and shrub cover for foraging. However, in the long-term this

species may benefit from the expansion of shrubs in lower

elevation grasslands facilitated by grazing and fire suppression

(GP 1999c).

Fox Sparrow (Passerella iliaca): The fox sparrow breeds

from Alaska east across northernmost Canada, and in the

Rocky Mountains south to Nevada, Utah, and Colorado. It is a

rare winter resident in Arizona and is considered rare to

uncommon as a winter resident in New Mexico, being absent

from the west-central/northwestern parts of this State (Hubbard

1978; Phillips and others 1964). While grazing may be a threat

to this species on its breeding grounds elsewhere in the West

(see Bock and others 1992), it is likely too sparse as a wintering

species in Arizona and/or New Mexico, and its habitat use is

too variable to be threatened by grazing activities in the

Southwest (GP 2000b; GP 2001n).

Swamp Sparrow (Melospiza georgiana): The swamp sparrow is a breeding bird of Canada and the Northeastern United

States. Its wintering grounds are primarily in the Midwestern

and Southeastern United States, Texas, and Northeastern

Mexico (AOU 1998; Mowbray 1997). In the Southwest, it

winters along the Colorado River south of Parker, AZ, and is

considered a “rare and irregular visitant in southeastern Arizona west to Tucson” (Phillips and others 1964). Winter

records exist from southern New Mexico, specifically the

lower Pecos River and Rio Grande valleys (Hubbard 1978;

Mowbray 1997). Potential threats from grazing in the Southwest include the degradation of dense weedy, grassy riparian

bottomlands containing rushes and sedges, riparian scrub, and

moist shrubby areas with cattails (GP 1999d). However, wintering numbers are believed to be quite sparse, with no breeding activity in the Southwest; thus, any impact on this species

would be unlikely to be severe (GP 2001n).

White-Throated Sparrow (Zonotrichia albicollis): This sparrow breeds chiefly across Canada and into northern New

England; it winters in southern New Mexico, and more rarely

in Arizona. Breeding Bird Survey data show this species to be

declining throughout much of its breeding range (Sauer and

others 2001). Wintering habitat includes thick brush in ravines

and along watercourses (Falls and Kopachena 1994). Grazing

can negatively impact this species when shrub communities

are destroyed or removed; conversely, promotion of shrub

expansion can increase wintering habitat (GP 1999d). Whitethroated sparrows are at the westernmost fringe of their wintering range in the Southwest, and there is no identifiable limiting

habitat component here. Because they are not considered to be

numerous in this region, grazing is not likely to impact this

species (GP 2001a).

Harris’ Sparrow (Zonotrichia querula):This primarily Great

Plains species is considered “rare” to “uncommon and local”

as a migrant and wintering bird in New Mexico (Hubbard

1978). Its occurrence in New Mexico is not considered to be

significant enough for the species to be affected by grazing or

range management practices in the region (GP 2000b).

Dark-Eyed Junco (Junco hyemalis):An apparently common

and relatively abundant species, the dark-eyed junco breeds

and winters extensively throughout North America, including

Arizona and New Mexico (Williams 1993). In Arizona, this

species is a common resident in the boreal forests of the Kaibab

and Mogollon Plateaus and a fairly common summer resident

in the adjacent Transition Zone and on the Coconino Plateau.

It is an abundant transient throughout the State and an abundant

winter resident of the open forests and woods of the Upper

Sonoran Zone and higher zones (Phillips and others 1964). In

New Mexico, it occurs widely in the eastern part of the State

and is local in the western part of the State (Hubbard 1978). The

dark-eyed junco may respond negatively to grazing because it

is largely a ground forager and nester (Bock and others 1994).

Detrimental effects would include removal of herbaceous

plants and litter necessary for nest cover and insect production,

especially the loss of suitable vegetation in riparian areas (GP

1999c). Given this species’ widespread distribution over a

variety of riparian and woodland habitats in the Southwest,

these effects were not considered to be significant enough to

affect this species (GP 2000e).

McCown’s Longspur (Calcarius mccownii): This species

winters in southern New Mexico and far southeastern Arizona

after breeding in Wyoming, Montana, and adjoining provinces

of Canada; this breeding range is considered to have been

“drastically reduced” (Krause 1968). Winter range consists of

open habitats with sparse vegetation in shortgrass prairie,

overgrazed pastures, plowed fields, and dry lakebeds (With

1994). The effect of grazing on this species is unclear in the

breeding range and virtually unknown in the winter range;

McCown’s longspur is considered one of the few avian species

that may actually benefit from grazing (With 1994). At the

Muleshoe National Wildlife Refuge (western Texas),

McCown’s longspur is most abundant (62 birds per 100 ha) on

lightly grazed pastures (Grzybowski 1982).
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 57

Bronzed Cowbird (Molothrus aeneus):This cowbird reaches

the southern extent of its breeding range in southern Arizona,

New Mexico, and Texas (AOU 1998). As a brood parasite,

similar to the brown-headed cowbird, it may be threatened by

any activity that reduces the availability of host species.

However, grazing is unlikely to impact this species, and the

presence of cattle herds and pastures may in fact be beneficial

(GP 2000b).

Red Crossbill (Loxia curvirostra): A bird of high-elevation

coniferous forests, the red crossbill specializes on feeding on

seeds within pine cones. It is found in northern and eastern

Arizona, and north-central and western New Mexico. Breeding habitat is in mature conifer forests, where large seed crops

have been produced by spruce, Douglas-fir, hemlock, or pines

(Adkisson 1996). Ungulate grazing (along with fire suppression and logging) has the potential to cause fire regime changes

leading to growth limits on big trees, limits on recruitment of

large trees, and catastrophic fire (GP 1999c). However, it was

considered unlikely that the effects of grazing among these

factors would be significant enough to create a severe negative

impact on this species (GP 2000e).

American Goldfinch (Carduelis tristis):The American goldfinch is abundant and widely distributed in adequate habitat

throughout temperate North America (Middleton 1993). In

Arizona, it is “rather common” but variable in numbers during

the winter (Monson and Phillips 1981; Phillips and others

1964). This species is abundant in New Mexico in winter in a

wide variety of habitats with deciduous trees; it is not necessarily tied to riparian areas (GP 2001n). Studies of grazing effects

on the American goldfinch have found lower abundance of this

species in cottonwood/willow, cottonwood/pine, and willow

riparian areas where grazing occurred (Crouch 1982; Mosconi

and Hutto 1982; Taylor 1986), but none of these decreases

were statistically significant. The general abundance of this

species in a variety of deciduous habitats and the lack of

unequivocal evidence of negative effects from grazing led the

Stage II panel to conclude that it would be unlikely to suffer

severe impacts from grazing in the Southwest (GP 2001b).

Mammals

Occult Bat (Myotis occultus): In the recent scientific literature, there is some disagreement as to whether this taxon

should be considered a separate species (Piaggio and others

2002) or a subspecies of the little brown bat (Valdez and others

1999). Also known as the Arizona bat (Hoffmeister 1986), it

ranges from New Mexico across Arizona and into far southern

California adjacent to the lower Colorado River. Hall (1981)

placed the subspecies M. lucifugus occultusin all areas of New

Mexico except the eastern plains and the north-central mountains; its distribution now includes Colorado (Piaggio and

others 2002). Hoffmeister (1986) reports that this bat is usually

found in ponderosa pine and oak-pine woodlands, and in areas

with cottonwoods, willows, and sycamores. However, in New

Mexico, Findley and others (1975) report that vegetation zone

appears to be unimportant in determining distribution. In the

arid Southwest, grazing could potentially impact the riparian

areas that are important in providing water sources to support

an insect prey base, as well as in creating a relatively humid

microclimate for roost sites. However, their wider distribution

and greater abundance relative to other species makes them

less likely to be impacted by grazing or range management

practices in the Southwest (GP 2003).

Yuma Myotis (Myotis yumanensis): The Yuma myotis is

generally considered a species of special concern (Harvey and

others 1999) and is on some State lists of sensitive species (for

example, Oregon; Marshall and others 1996 as cited in Betts

1997). Population declines over a 25-year period have been

recorded for specific sites in Arizona (O’Shea and Vaughan

1999). The Yuma myotis occurs across a wide range of

habitats, from British Columbia, south to include Washington,

Oregon, Idaho, western Montana, California, south-central

Utah, southeastern Colorado, Arizona, New Mexico, and western Texas. In Mexico, it occupies Baja California and Northwestern to Central Mexico (Harris 1999). This bat occurs in a

wide variety of habitats across its range; in the Southwest, it is

generally associated with cottonwood streamside forests, although it is often found in areas without trees if open water is

present (Harvey and others 1999). In Arizona, they are found

wherever permanent water sources provide foraging habitat

(Hoffmeister 1986). The Yuma myotis could be impacted by

grazing systems or management practices that degrade riparian water sources, divert water, or eliminate streams. However,

given that these bats are found in a wide variety of habitats,

choose a variety of structures for roost sites, and are generally

widespread and common, it is unlikely that grazing or range

management activities would have severe negative impacts on

this species (GP 2003).

Western Hog-Nosed Skunk (Conepatus mesoleucus): The

range of this species extends from Arizona and New Mexico

east to central Texas, and south through most of Mexico to

Nicaragua. The modern distribution is reduced from its historical range, which included Colorado and Oklahoma (Dragoo

and Honeycutt 1999). In Arizona, hog-nosed skunks range

from southeastern Arizona, north to the Mogollons, and occasionally further north and northwest (Hoffmeister 1986). Findley

and others (1975) describe the hog-nosed skunk as a species of

southern New Mexico; Bernalillo County represents a northern limit to its range. Throughout the Southwest, western hognosed skunks are known from canyons, stream beds, and the

rocky terrain of desert-scrub and mesquite grasslands (Dragoo

and Honeycutt 1999). They appear to occupy open and wooded

areas but avoid dense forest (Nowak 1999). Although unlikely

to have significant negative impacts on this species (GP

2001p), grazing may alter the vegetation structure that serves

as groundcover, and any reduction in vegetation may also

reduce the insect prey base (GP 1999e).

Northern Raccoon (Procyon lotor): Racoons are quite common throughout the United States and range from southern

Canada across the entire United States (with the exception of

extremely arid desert areas of the Southwest), Mexico, and

Central America, south to Panama (Nowak 1999). In Arizona,
58 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

the raccoon occurs along the waterways of central and southern

Arizona, as well as along the Colorado and Little Colorado

Rivers and their tributaries, and streams in the ChuskaLukachukai Mountains (Hoffmeister 1986). In New Mexico,

raccoons are common near all permanent watercourses up to

timberline (Findley and others 1975). Raccoons depend on

riparian vegetation for habitat, and aquatic vertebrates and

invertebrates are important food resources. Although unlikely

to have significant negative impacts on this species (GP

2001q), grazing and stocking practices that degrade riparian

vegetation, marshlands, and water quality may eliminate habitat and prey species of the raccoon (GP 1999e).

Harris’ Antelope Squirrel (Ammospermophilus harrisii):

The Harris’ antelope squirrel ranges from western and southern Arizona and southwestern New Mexico south to westcentral Sonora, Mexico (Hall 1981 as cited in Best and others

1990). In Arizona the Harris’s antelope squirrel occurs in

nonwooded areas south of the Mogollon Plateau in the western

and southern sections of the State (Hoffmeister 1986). In New

Mexico, the species occurs in the foothills and valleys of the far

southwestern counties (Bailey 1932; Findley 1987; Findley

and others 1975). The Harris’s antelope squirrel occupies low

deserts often in association with rocky soils or rocky slopes,

with cacti or desert shrubs used for locating burrow entrances

(Best and others 1990; Hoffmeister 1986). The effects of

grazing are unlikely to be severe (2001d) but may be mixed:

conversion of grassland to scrubland could benefit this animal,

but there could be damage to burrows and competition for food

items (GP 1999e).

White-Tailed Antelope Squirrel (Ammospermophilus

leucurus): This a species primarily of the Great Basin and is at

the southern/southeastern edge of its distribution in Arizona

and New Mexico. It occurs in Arizona north of the Mogollon

Plateau (Hoffmeister 1986), and in New Mexico its distribution extends from the Four-Corners area south and east along

the Rio Grande Valley to Socorro County; it is evidently absent

from west-central New Mexico (Findley 1987; Findley and

others 1975). Habitats occupied by white-tailed antelope squirrels range from grassland and shrub land to the lower edge of

pinyon-juniper woodland. Although they are also found on

rocky slopes, they may prefer flat, often sandy areas (Findley

and others 1975; Hoffmeister 1986). Given that the dietary

components for this species are broad and variable, its habitat

requirements are unlikely to be negatively impacted by grazing

or range management practices (GP 2001d).

Spotted Ground Squirrel (Spermophilus spilosoma): The

spotted ground squirrel ranges from the central and western

Great Plains through the Southwestern United States to central

Mexico (Fitzgerald and others 1994). It occurs in grasslands

and deserts throughout New Mexico (Findley and others

1975). In Arizona it occurs in two distinct areas: the northern

part of the State, south and east of the Colorado River and north

of the Mogollon Plateau, and in the southeast (Hoffmeister

1986). The spotted ground squirrel occupies a wide variety of

habitats ranging from arid deserts and grasslands to montane

meadows. In southeastern Arizona the species is associated

with mesquite and acacia, while in the north it is found in

saltbush and sagebrush (Hoffmeister 1986). In New Mexico it

can be found in arid deserts and grasslands, shinnery oakmesquite grassland, shortgrass plains, sacaton grassland, sycamore, cottonwood, and rabbitbrush (Best and others 1993;

Cook 1986; Findley 1987; Findley and others 1975). The

spotted ground squirrel seems especially common in arid,

often disturbed, areas with scarce vegetation (Findley and

others 1975; Fitzgerald and others 1994). Many studies have

indicated that livestock grazing appears to benefit the spotted

ground squirrel, as it appears to prefer sandy areas with scarce

vegetation such as overgrazed sandhills and lightly-grazed

mixed-grass prairie (see Streubel and Fitzgerald 1978 and

authors cited therein).

Botta’s Pocket Gopher (Thomomys bottae): Broad in distribution, from southern Oregon south through all of Baja California and eastward to central Texas. It is found throughout

Arizona except for several local absences (Hoffmeister 1986)

and in all but easternmost New Mexico (Findley and others

1975). Throughout its range, this species can be found in

almost any friable soil, from rich bottomlands to rocky mountain slopes, in habitats ranging from desert scrub to coniferous

forests (Patton 1999). This species was found to be significantly lower in abundance in grazed versus ungrazed annual

grasslands in California; soil compaction by heavy livestock

use was speculated to be at least partially responsible (Hunter

1991). While some of the numerous subspecies described

under T. bottae may be locally vulnerable to heavy livestock

use, the species as a whole is unlikely to be severely impacted

by grazing in the Southwest (GP 2001d).

Plains Pocket Mouse (Perognathus flavescens): The plains

pocket mouse is found in southeastern North Dakota, southwestern Minnesota, and northern Iowa, southwest to the Rio

Grande and San Juan valleys of New Mexico, and northeastern

Arizona (Bailey 1932; Hoffmeister 1986). This pocket mouse

lives in sandy habitats (including dunes or shifting sands). The

vegetation tends to be sparse and widespread; as long as sand

is available, it can live in pinyon-juniper or ponderosa pine

woodlands (Bailey 1932; Findley and others 1975; Hoffmeister

1986). In Arizona in some cases, the expanse of sand is so

extensive that there is no plant material visible for many

surrounding meters (Hoffmeister 1986). In New Mexico, this

species is not always restricted to sandy soils, especially in

woodlands (Findley and others 1975). Rangeland practices

such as mechanical clearing of brush may actually benefit this

species, and livestock use would have to be extremely high,

essentially denuding all vegetation, to cause any negative

impacts (GP 2001o).

Merriam’s Pocket Mouse (Perognathus merriami): This

species is found from eastern New Mexico (east of the Pecos

River and south of the Canadian River), the western two-thirds

of Texas, and extreme southwestern Oklahoma, south into

Mexico (Best and Skupski 1994); it does not occur in Arizona

(Hoffmeister 1986). The Merriam’s pocket mouse is a resident

of shortgrass prairie and desert scrub over most of its range,

often with sparse vegetation. In northern Texas, it is most
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 59

common in well-grazed or over-grazed pastures with mesquite

(Dalquest and Horner 1984 as cited inBest and Skupski 1994).

Grazing in dense grasslands may benefit this species by opening up the vegetation, which aids its movement for foraging

(GP 1999e).

Bailey’s Pocket Mouse (Chaetodipus baileyi): The Bailey’s

pocket mouse occurs in the Southwest at the northern edge of

its distribution. It ranges from extreme southern California,

central Arizona, and extreme southwestern New Mexico

(Peloncillo Mountains, Hidalgo County, and Burro Mountains, Grant County), south into Baja California and mainland

Mexico (GP 2001o; Findley and others 1975; Hoffmeister

1986; Price 1999). In New Mexico, Findley and others (1975)

describe the Bailey’s pocket mouse as inhabiting “xeric brushy

hillsides.” In Arizona the species occurs in Chihuahuan Desert

plant communities and in saguaro-palo verde associations of

the Sonoran Desert (Hoffmeister 1986; Reichman 1975). Habitat

is characterized by relatively sparse grass cover, with grasses

interspersed with open ground and with shrubs (GP 2001e).

Heavy grazing that reduces grasses for seed production would

locally impact this mouse; however, light grazing that increases small to medium shrubs for cover while retaining

herbaceous plants for seed production would be positive (GP

1999e).

Rock Pocket Mouse (Chaetodipus intermedius): The rock

pocket mouse is found from south-central Utah through central

Arizona, central New Mexico, and western Texas south into

western Sonora and Chihuahua, Mexico (Rogers 1999). Rock

pocket mice nearly always live in rocky areas, such as rock

ledges, rock piles, lava flows, and steep canyon slopes (Findley

and others 1975; Frey and Yates 1996; Hoffmeister 1986),

especially rocky areas within desert scrub habitats with creosote bush and salt-bush (GP 1999e). Vegetation is often

shrubby and scarce (Hoffmeister 1986). Because of the rocky

component of this species’ habitat, as well as the sparse,

shrubby nature of surrounding vegetation, grazing is not expected to have a negative impact on this species (GP 2001e).

Chihuahuan Pocket Mouse (Chaetodipus eremicus): The

Chihuahuan pocket mouse was formerly considered as a subspecies of the desert pocket mouse (C. penicillatus); the

distribution of C. eremicus generally corresponds to the

Chihuahuan Desert (Hall 1981). It occurs in Chihuahuan

desertscrub or associated xeroriparian vegetation, avoiding

rocky slopes in preference of sandy or silty soils, often near

desert washes. It is associated with shrubs such as mesquite,

catclaw, or creosote (Davis and Schmidly 1994; Findley and

others 1975; Schmidly 1977). Grazing could potentially benefit this species through opening of the herbaceous vegetation

layer, creating sandy soil areas, and increasing shrubby vegetation; however, heavy grazing intensities could potentially

reduce available seed availability (GP 1999e).

Desert Kangaroo Rat (Dipodomys deserti): The desert kangaroo rat ranges from Nevada south through California and

western Arizona to Baja California and Sonora, Mexico (Best

1999). It occurs in northwestern Arizona from Grand Canyon

National Park along the Nevada border north to the Utah

border; along the eastern side of the Colorado River in westcentral Arizona; in southwestern Arizona east to Scottsdale,

Florence, and Picacho (Hoffmeister 1986). The desert kangaroo rat occurs in the most arid regions of Southwestern North

America, in desert areas with loose sandy soil such as sand

dunes or arroyo bottoms (Best 1999; Best and others 1989;

Hoffmeister 1986). Although this species does require seeds as

a major diet item, grazing activity is not likely to have a

negative impact as it occupies arid, sandy habitats sparsely

vegetated with shrubs such as creosote (GP 2001e).

Merriam’s Kangaroo Rat (Dipodomys merriami): This species ranges from northwestern Nevada and southwestern Utah

south through western and southern Arizona, southern New

Mexico, and western Texas into Mexico (Bailey 1932; Reynolds

1958). In the Southwest the Merriam’s kangaroo-rat is found

in the Chihuahuan and Sonoran deserts (Findley 1987; Findley

and others 1975; Hoffmeister 1986). It is commonly associated

with mesquite, creosote, and cacti in both Arizona and New

Mexico (Findley and others 1975; Hoffmeister 1986). It seems

to prefer areas with annual grasses and scattered woody plants,

avoiding perennial grass areas. Numbers decrease with an

increase in the abundance of perennial grasses for any given

elevation or vegetation type (Reynolds 1958). The seeds of

grasses are an essential dietary item, but Merriam’s kangaroo

rat habitat is characterized by relatively sparse grass cover,

with grasses interspersed with open ground and with shrubs

(Hoffmeister 1986). Overall, livestock grazing is viewed as

having had a positive effect on the species in desert grassland

sites (Bock and others 1994; Loftin and others 2000; Reynolds

1958). Grazing reduces grass stubble height, but continuous

heavy grazing over several years also reduces perennial grass

cover. These influences make habitat more favorable to

Merriam’s kangaroo-rat, and this species is more abundant on

ranges grazed by cattle (Reynolds 1958). However, burrow

trampling and soil compaction may potentially produce negative effects (Heske and Campbell 1991).

White-Footed Mouse (Peromyscus leucopus): The whitefooted mouse ranges from the Northeastern United States,

south to northern South Carolina, and west to eastern Montana,

northern Colorado, and central Arizona (Hall 1981). In Arizona, Hoffmeister (1986) describes a variety of habitats, including areas along streams and rivers that had grasses, tumbleweeds, alder, cottonwoods, willow, and so forth growing

alongside them. In New Mexico, this species’ habitat is often

described as brushy or weedy places (Bailey 1932). Findley

and others (1975) described it as soft or sandy soils in arroyos

and grasslands below the woodland, with vegetation of Apache

plumes, saltbush, mesquites, and “other leguminous shrubs.”

White-footed mice can also be found in “tall grass and cottonwood groves” in some riparian areas (Findley and others

1975). Because of the variety of habitats it occupies, this

species was not considered to be vulnerable to grazing in the

Southwest (GP 2001o). However, because it is utilizes riparian

habitats of thick grass, brushy clumps, cottonwood-willow,

and tamarisk, the degradation of this habitat type and vegetation could locally affect this species (GP 1999e).
60 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Black-Eared Mouse (Peromyscus melanotis): The blackeared mouse is considered a sister species of the more widespread deer mouse (P. maniculatus) and is one of several

closely related species that form the P. maniculatus group.

Primarily a high-elevation species of central Mexico (Handley

1999), the black-eared mouse ranges as far north as southeastern Arizona and may occur in the Chiricahua, Graham, and

Santa Catalina Mountains (Bowers 1974; Bowers and others

1973). It is not known to occur in New Mexico. In Arizona,

black-eared mice are primarily known from montane meadows in the southeastern mountains where they could be locally

impacted by intense grazing in these areas (GP 1999e).

Pinyon Mouse (Peromyscus truei):The pinyon mouse occurs

from Oregon and Wyoming south through portions of California, Nevada, Utah, Colorado, Arizona, New Mexico, Texas,

and Oklahoma, and south into Oaxaca, Mexico (Hoffmeister

1981). It is usually found in conjunction with pinyon trees or

pinyon-juniper, especially where stands of these trees are near

walls, cliffs, outcrops, or rocky slopes. They can also occasionally be found in cottonwood stands in riparian areas such as

along the Little Colorado River, or sandy grassland habitats

with scattered shrubs or junipers (Bailey 1932; Cornely and

others 1981; Findley and others 1975; Hoffmeister 1981). If

range management practices include clearing of pinyon woodlands, the pinyon mouse will be negatively affected (GP

1999e); however, the Stage II panel (GP 2001o) did not

considered this to be a significant threat to this species in the

Southwest.

Northern Grasshopper Mouse (Onychomys leucogaster):

The northern grasshopper mouse occurs from “Saskatchewan,

Alberta, and Manitoba south to extreme northern Mexico, west

into northeastern California and central Oregon and east to

western Minnesota and Iowa” (McCarty 1978). In Arizona, it

occurs mostly in the northern portion of the State (north of the

Mogollon Plateau) but also “south in Yavapai County to Camp

Verde; south of the Mogollon Plateau from near the Gila River

south through Cochise County” (Hoffmeister 1986). In New

Mexico, it occurs in scattered locations throughout the state

(Bailey 1932; Findley and others 1975). Northern grasshopper

mice prefer areas with sparse vegetation (including sagebrush

flats, yucca, and mesquite, all with sparse grass) and friable soil

(Hoffmeister 1986). In New Mexico, they are found in the

plains country, in sandy grasslands, mesquite stands, weedy

areas, and dunes (Bailey 1932; Findley and others 1975).

Overall, the Stage II panel concluded that severe effects on this

species were unlikely (GP 2001o), but there are negative

factors related to grazing worth noting. A study in southeastern

Arizona found a “modest negative effect of cattle grazing” on

some rodents, especially kangaroo rats and grasshopper mice

(Heske and Campbell 1991). These authors speculated that

negative effects could include trampling of burrows, alteration

of plant composition, loss of food for insect prey, direct

competition for seed heads, and soil compaction (Heske and

Campbell 1991). While grasshopper mice choose unvegetated

areas, possibly for “ease of travel or because these areas

support higher densities of insect prey,” they also have a high

affinity for burrows associated with gopher mounds (Stapp

1997). Thus, any management program that eradicated gophers would likely have a negative effect on these mice as well.

White-Throated Woodrat (Neotoma albigula): The whitethroated woodrat is considered the most common woodrat of

New Mexico (Findley 1987) and is common in Arizona

(Hoffmeister 1986). It is widespread throughout both States,

except for the northwestern corner of Arizona, north and west

of the upper Colorado River (Hoffmeister 1986). The whitethroated woodrat is found in desertscrub, desert grassland, oak

associations, pinyon-juniper woodland, and riparian areas

(Cook 1986; Findley 1987; Hoffmeister 1986). A key component of the white-throated woodrat’s habitat in many areas is

cactus, which is consumed and used for shelter (Findley 1987;

Hoffmeister 1986; Vorhies and Taylor 1940). According to

Vorhies and Taylor (1940), the white-throated woodrat is often

found at highest densities in heavily-grazed areas. However,

Steenbergh and Warren (1977) observed the opposite, with the

species preferring areas with more vegetation cover and avoiding overgrazed rangelands. The Stage II panel ultimately

decided that effects were not serious enough to warrant inclusion in the database (GP 2001e).

Mexican Woodrat (Neotoma mexicanus): This species is

associated with the mountain ranges of Arizona and New

Mexico (Findley and others 1975; Hoffmeister 1986). It is

found in eastern Arizona, as far west as the Hualapai Mountains and as far north as the Colorado River (Hoffmeister

1986). In New Mexico, this species has also been found at low

elevation sites such as at Elephant Butte, Carrizozo malpais,

and Alamogordo Reservoir (Findley and others 1975). The

Mexican woodrat is associated with montane coniferous forests and reaches greatest abundance in mixed coniferous

forests; it prefers rock outcrops, rocky slopes, and cliffs in the

upper Sonoran and transition zones (Findley and others 1975;

Hoffmeister 1986). It is unlikely to be affected by grazing

except for impacts to important food items (for example,

leaves, green plants, berries, fruits, seeds, nuts, acorns, and

mushrooms) (GP 2001d).

North American Porcupine (Erethizon dorsatum): The porcupine occurs throughout most of Alaska and Canada, south to

Virginia, Tennessee, central Illinois, and Iowa, and then into

the American Southwest and the northern part of Mexico (Hall

1981). It occurs in appropriate habitat throughout New Mexico

and Arizona (Findley and others 1975; Hoffmeister 1986).

Records from Arizona south of the Gila River are primarily

from desert scrub (Hoffmeister 1986). Bailey (1932) reports

them as common in the mountains of northern New Mexico

and “not infrequently found” elsewhere in valleys, canyons,

and on cliffs. In the Southwestern United States, porcupines

are considered most abundant in forested areas, especially

coniferous forests, as well as riparian woodlands (Woods

1973, 1999). In Mexico, the habitat of the North American

porcupine is negatively impacted by overgrazing, which alters

the structure and composition of riparian vegetation (List and

others 1999). The Stage II panel (GP 2001o) did not consider

the potential for negative impacts to be significant but noted
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 61

that in Arizona and New Mexico porcupines may be affected

by grazing in riparian or xeroriparian areas that results in the

degradation of deciduous woodlands and the loss of trees and

shrubs used as food and cover. In low elevation grasslands,

grazing may have long-term positive effects by increasing

shrub densities (GP 1999e).

Desert Cottontail (Sylvilagus audubonii): This rabbit ranges

throughout much of the Western United States to Southern

Mexico (Hall 1981). It is widespread and considered common to

abundant at lower elevations throughout New Mexico and

Arizona (Findley 1987; Hoffmeister 1986). The desert cottontail

is chiefly a grassland and shrubland species; it may also occur in

oak or pinyon-juniper woodlands (Findley 1987; Hoffmeister

1986). In the Animas Mountains area, it occupies cottonwoodsycamore associations and rabbitbrush of riparian areas (Cook

1986). Elsewhere the desert cottontail is often associated with

xeroriparian vegetation (Hoffmeister 1986). Desert cottontails

prefer plant associations that include some shrubs. In Colorado,

moderate livestock grazing has a positive effect on the desert

cottontail when it promotes an increase in shrub cover and in

broad-leaved herbs (Flinders and Hansen 1975).
62 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Bacteria

Plague Bacterium Yersinia pestis

Fungi

Shelf Fungus Fomes igniarius var. populinus

Plants

Acacia Acacia spp.

Agave Agave spp.

Alder Alnus spp. (includes A. oblongifolia)

Alfalfa Medicago sativa

Algerita Berberis spp.

Alkali Bulrush Scirpus maritimus

Alkali Sacaton Sporobolus airoides

Alligator-Bark Juniper Juniperus deppeana

Allthorn Koeberlinia spp.

American Lotus Nelumbo lutea (see also Water Chinquapin)

Antelope Bush Purshia tridentata

Apache Pine Pinus engelmannii

Apache Plume Fallugia paradoxa

Arizona Cypress Cupressus arizonica

Arizona Hackberry Celtis pallida

Arizona Madrone Arbutus arizonica

Arizona Pine Pinus strobiformis (see also White and Southwestern Pine)

Arizona Sycamore Platanus wrightii

Arizona Walnut Juglans major

Arizona White Oak Quercus arizonica

Arrow Arum Peltandra virginica

Arrowweed Tesseria sericea

Ash Fraxinus spp.

Aspen Populus spp.

Baccharis Baccharis spp.

Balsam Fir Abies balsamea

Baltic Rush Juncus balticus

Barrel Cactus Ferocactus spp.

Bear Grass Xerophyllum tenax

Bearberry Arctostaphylos uva-ursi (see also Kinnickinnick)

Beargrass Nolina microcarpa

Bedstraw Galium spp.

Bermuda Grass Cynodon dactylon

Big Sagebrush Artemesia tridentata

Birch Betula spp.

Bird-of-paradise Caesalpinia gilliesii

Bitterbrush Encelia farinose

Appendix E—Common Names and Scientific Names ___________________

Common names for various organisms are used in lieu of

Latin scientific names throughout the text of the species

accounts, with the exception of discussions specifically related

to taxonomic relationships or nomenclature. The following list

allows users to cross reference the scientific name for any

common name used in the accounts. Species are listed first by

major taxonomic group, then alphabetically by common name.

Some scientific names are associated with multiple common

names, which is noted parenthetically. (Names of species that

are part of the grazing assessment database are not included

here; see table 2.)
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 63

Black Grama Bouteloua eriopoda

Black Greasewood Sarcobatus vermiculatus

Black Oak Quercus kelloggii

Black Spruce Picea mariana

Black Walnut Juglans major

Blackberry Rubus spp.

Blackbrush Coleogyne ramosissima

Blackbush Acacia rigidula

Blanketflower Gaillardia aristata

Blazing Star Mentzilia pumila

Blue Elderberry Sambucus nigra cerulea

Blue Grama Bouteloua gracilis

Blue Oak Quercus douglasii

Blue Paloverde Cercidium florida

Blue Spruce Picea pungens

Blueberry Vaccinium spp.

Bluegrass Poa spp.

Bluestem Andropogon spp.

Bog Birch Betula glandulosa

Border Pinyon Pine Pinus discolor

Bouvardia Bouvardia glaberma

Box-elder Acer negundo

Boxthorn Lycium spp. (see also Desert Thorn)

Bristlegrass Setaria spp.

Brome Bromus spp.

Broom(-weed) Gutierrezia sarothrae

Buckhorn (Cholla) Opuntia acanthocarpa; also O. whipplea

Buckhorn (-thorn) Rhamnus spp.

Buckwheat Eriogonum spp.

Buffalograss Buchloe dactyloides

Bull Muhly Muhlenbergia emersleyi

Bullthorn Acacia cornigera

Bulrush Scirpus spp.

Bur Reed Sparganium americanum

Burro Grass Scleropogon brevifolius

Burrobrush (-bush) Hymenoclea monogyra

Burroweed Ambrosia dumosa

Bursage Franseria spp.

Buttonbush Cephalanthus occidentalis

California Bulrush Scirpus californicus

Cane Bluestem Bothriochloa barbinodis

Canyon Grape Vitis arizonica

Canyon Live Oak Quercus chrysolepis

Canyon Maple Acer grandidentatum

Canyon Ragweed Ambrosia artemisifolia

Cardón Cactus Pachycereus pringlei

Carpetweed Mollugo verticillata

Catclaw Acacia greggii

Catclaw Acacia Acacia greggii

Cattail Typha spp.; includes T. angustifolia

Ceanothus Ceanothus spp.

Cedar Elm Ulmus crassifolia

Celery Vallisneria americana

Cheatgrass Bromus tectorum

Cherry Prunus serotina

Chihuahuan Pine Pinus leiophylla
64 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Chokecherry Prunus virginiana

Cholla Cactus Opuntia spp. (includes O. imbricata)

Chuparosa Justicia californica

Cinquefoil Potentilla fruticosa

Clover Trifolium spp.; also Dalea spp.

Common Watercress Nasturtium officinale

Copper Mallow Sphaeralcea coccinea

Coralbean Erythrina flabelliformis

Corkbark Fir Abies lasiocarpa var. arizonica

Cottonwood Populus spp.

Cottonwood Mistletoe Phoradendron flavescens

Coyote Bush Baccharis spp.

Creosote (-bush) Larrea tridentata

Crested Wheatgrass Agropyron cristatum

Curly Dock Rumex crispus

Dalea Dalea spp. (see also Clover)

Dandelion Taraxacum spp.

Dasylirion Dasylirion spp. (see also Sotol)

Desert Hackberry Celtis pallida

Desert Mistletoe Phoradendron californicum

Desert Honeysuckle Anisacanthus thurberi

Desert Lavender Hyptis emoryi

Desert Penstemon Penstemon pseudospectabilis

Desert Saltgrass Distichlis spicata

Desert thorn Lycium spp. (see also Boxthorn)

Desert Willow Chilopsis linearis

Dock Rumex spp.

Douglas-fir Pseudostuga menziesii

Dropseed Sporobolus spp. (includes S. contractus; see also Sacaton)

Duckweed Lemna spp.; also Spirodela spp.

Dwarf Birch Betula nana

Elderberry Sambucus spp.

Elephant Tree Bursera microphylla

Elm Ulmus spp.

Emory Oak Quercus emoryi

Englemann Spruce Picea engelmannii

Ephedra Ephedra spp. (see also Joint-fir, Mormon Tea)

Evening Primrose Oenothera minor

False Grama Cathestecum brevifolium

Fig Ficus spp.

Fir Abies spp.

Fireweed Epilobium canum

Flatsedge Cyperus spp.

Foothill Paloverde Cercidium microphylla

Four-winged Saltbush Atriplex canescens

Fremont Cottonwood Populus fremontii

Galleta Hilaria jamesii

Gambel Oak Quercus gambelii

Giant Cane Arundo donax

Giant Reed Arundo donax

Giant Sacaton Sporobolus wrightii

Globemallow Sphaeralcea spp.

Goldenrod Solidago spp.

Goldenweed Pyrrocoma spp.

Gooding Willow Salix goodingii

Gooseberry Ribes spp.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 65

Goosefoot Chenopodium spp.

Grama Bouteloua spp.

Grand Fir Abies grandis

Grape Vitis spp.

Graves Oak Quercus gravesii

Gray Oak Quercus grisea

Graythorn Ziziphus obtusifolis

Greasebrush (-bush) Glossopetalon spinescens

Greasewood Sarcobatus vermiculatus

Green Joint-Fir Ephedra viridis (see also Mormon Tea)

Groundsel Senecio vulgaris

Hackberry Celtis spp.

Hairy Grama Bouteloua hirsute

Hall’s Panic Grass Panicum hallii

Heather Family Ericaceae (see Manzanita, Madrone, Kinnikinnick)

Hemlock Tsuga spp.

Honey Mesquite Prosopis glandulosa

Hopbush Dodonaea viscosa

Horsetail Equisetum spp.

Huckleberry Vaccinium myrtillus

Incense Cedar Calocedrus decurrens

Indian Paintbrush Castilleja confusa

Ironwood Olneya tesota

Jeffery Pine Pinus jeffreyi

Jimsonweed Datura stramonium

Joint-Fir Ephedra torreyana (see also Mormon Tea)

Jojoba Simmondsia chinensis

Joshua Tree Yucca brevifolia

Juniper Juniperus spp.

Kentucky Bluegrass Poa pratensis

Kinnikinnick Arctostaphylos uva-ursi (see also Bearberry)

Knotgrass Paspalum spp.

Lamb’s Quarters Chenopodium album

Limber Pine Pinus flexilis

Little Bluestem Schizachyrium scoparium

Little-Leaf Sumac Rhus microphylla

Lodgepole Pine Pinus contorta

Lousewort Pedicularis spp.

Lovegrass Eragrostis spp.

Madrone Arbutus spp.

Manzanita Arctostaphylos spp.

Maple Acer spp.

Mescal Sophora secundiflora

Mesquite Prosopis spp.

Mesquite Mistletoe Phoradendron californicum

Mexican Elderberry Sambucus spp.

Mexican Pinyon Pine Pinus cembroides

Milkweed Asclepias spp.

Mistletoe Phoradendron spp.

Mojave Beard-Tongue Penstemon pseudospectabilis(see also Desert Penstemon)

Mormon Tea Ephedra torreyana; also E. viridis (see also Joint-fir)

Mountain Birch Betula glandulosa

Mountain Dandelion Agoseris glauca

Mountain Lover Pachystima myrsinites

Mountain Mahogany Cercocarpus montanus

Muhly Muhlenbergia spp.
66 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Mulberry Morus spp.

Muscadine Vitis rotundifolia

Mustard Brassica spp.

Narrowleaf Cottonwood Populus angustifolia

Netleaf Hackberry Celtis reticulata

New Mexico Locust Robinia neomexicana

New Mexico Thistle Cirsium neomexicanum

Nipple Cactus Mammilaria spp.

Nuttall Oak Quercus nuttallii

Oak Quercus spp.

Ocotillo Fouquieria splendens

One-Seeded Juniper Juniperus monosperma

Onion Allium spp.

Paintbrush Castilleja spp.

Palm Washingtonia spp.

Palmillo Yucca elata

Paloverde Cercidium spp.

Panic Grass Panicum spp.

Panicum Panicum spp.

Parry’s Beard-Tongue Penstemon parryi

Parry’s Century-Plant Agave parryi

Pecan Carya illinoinensis

Penstemon Penstemon spp.

Pigweed Amaranthus retroflexus

Pin Oak Quercus palustris

Pine Pinus spp.

Pinyon Ricegrass Piptochaetium fimbriatum

Pointleaf Manzanita Arctostaphylos pungens

Poison Ivy Rhus radicans

Ponderosa Pine Pinus ponderosa

Pondweed Potamogeton spp.

Poplar Populus spp.

Prickly-Pear Cactus Opuntia spp. (includes O. phaeacantha)

Purple Sandgrass Triplasis purpurea

Quaking Aspen Populus tremuloides

Rabbitbrush (-bush) Chrysothamnus spp.

Ragweed Ambrosia artemisifolia

Raspberry Rubus spp.

Red Alder Alnus rubra

Red Barberry Berberis haematocarpa

Red Brome Bromus rubens

Red Cedar Thuja spp.

Red Maple Acer rubrum

Redberry Rhamnus spp. (see also Buckhorn, -thorn)

Reed Phragmites spp.

Rice Zizania spp.

Ricegrass Oryzopsis spp.

Rocky Mountain Maple Acer glabrum

Rocky Mountain Pinyon Pine Pinus edulis

Rose Rosa spp.

Rush Juncus spp.; also Scirpus spp.

Russian Olive Eleagnus angustifolia

Russian Thistle Salsola kali

Sacaton Sporobolus spp. (see also Dropseed)

Sagebrush Artemesia spp.

Saguaro Cactus Carnegiea gigantea
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 67

Salt Cedar Tamarix pentandra; also T. chinensis, T. ramosissina

Saltbush Atriplex spp.

Saltgrass Distichlis spp.

Sand Bluestem Andropogon hallii

Sand Dropseed Sporobolus cryptandrus

Sand Sagebrush Artemisia filifolia

Sandbur Cenchrus spp.

Saw Grass Cladium jamaicense

Scarlet Bugler Penstemon barbatus

Scenecio Scenecio spp.

Schott Yucca Yucca schottii

Screwbean Mesquite Prosopis pubescens

Scrub Oak Quercus turbinella

Sedge Carex spp.; also Cyperus spp.

Sedge Nutgrass Cyperus rotundus

Seepwillow Baccharis glutinosa

Serviceberry Amelanchier utahensis

Shadscale Atriplex confertifolia

Shindagger Agave schottii

Shinnery Oak Quercus havardii

Sideoats Grama Bouteloua curtipendula

Silver-Leaf Oak Quercus hypoleucoides

Singleleaf Pinyon Pine Pinus monophylla

Skunkbush Rhus spp.

Smartweed Polygonum spp.

Smoketree Psorothamnus spinosa

Snakeweed Gutierrezia sarothrae

Snowberry Symphoricarpos spp.

Soapberry Sapindus saponaria

Soaptree Yucca Yucca elata

Sorghum Sorghum spp.

Sotol Dasylirion wheeleri

Southwestern Pine Pinus strobiformis (see also Arizona and White Pine)

Spikerush Eleocharis spp.

Spineless Hopsage Grayia brandegei

Spruce Picea spp.

Squaw Currant Ribes cereum

Stickleaf Mentzilia pumila

Subalpine Fir Abies lasiocarpa

Sugar (or Sugarberry)

 Hackberry Celtis laevigata

Sumac Rhus spp.

Sunflower Helianthus spp.

Superb Penstemon Penstemon superbus

Switch Grass Panicum spp.

Sycamore Plantanus spp.

Tabosa Grass Hilaria mutica

Tall Mesquite Prosopis glandulosa

Tamarack Larix spp.; includes L. laricina

Tamarisk Tamarix pentandra; also T. ramosissima, T. chinensis

Tarbush Flourensia cernua

Tetetzo Cactus Neobuxbaumia tetetzo

Texas Betony Stachys coccinea

Thistle Cirsium spp.

Three-Awn Aristada spp.

Three-Square Bulrush Scirpus olneyi
68 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Torpedograss Panicum spp.

Torrey Yucca Yucca torreyi

Toumey Oak Quercus toumeyi

Tridens Tridens spp.

Trumpet Honeysuckle Lonicera sempervirens

Tule Schoenoplectus acutus

Tumbleweed Amaranthus albus

Utah Juniper Juniperus osteosperma

Velvet Ash Fraxinus velutina

Velvet Mesquite Prosopis velutina

Vetch Vicia americana

Vine Mesquite Panicum obtusum

Walnut Juglans spp.

Water Chinquapin Nelumbo lutea (see also American Lotus)

Water Milfoil Myriophyllum sibiricum

Water Oak Quercus nigra

Water Star Grass Heteranthera dubia

Wavyleaf Oak Quercus undulata

Wax Mallow Malvaviscus arboreus

Weeping Brome Bromus frondosus

Weeping Lovegrass Eragrostis curvula

Western Wheatgrass Agropyron smithii

Wheatgrass Agropyron spp.

White Bursage Franseria dumosa

White Cedar Thuja occidentalis

White Fir Abies concolor

White Heather Cassiope spp.

White Pine Pinus strobiformis (also Arizona and Southwestern Pine)

White Water Lily Nymphaea odorata

White-Thorn Acacia constricta

Wigeon Grass Ruppia maritime

Willow Salix spp.

Willow Oak Quercus phellos

Winterfat Eurotia lanata

Wolfberry Lycium exsertum

Wolftail Lycurus pheloides

Wood Sorrel Oxalis violacea

Woolly Buckthorn Bumelia lanuginose

Yarrow Achillea millefolium

Yellow Paloverde Cercidium microphylla

Yellow Pine Pinus leiophylla

Yucca Yucca spp.

Invertebrates

Brown-Tail Moth Euprocitis chrysorrhoea

Coddling Moth Cydia pomonella

Crayfish Orconectes virilis

Douglas-fir Tussock Moth Orgyia pseudotsugata

Gypsy Moth Lymantria dispar

Tent Caterpillar Malacosoma spp.

Western Spruce Budworm Choristoneura occidentalis

Fish

Bass Micropterus spp.

Desert Sucker Catostomus clarki
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 69

Fathead Minnow Pimephales promelas

Green Sunfish Lepomis cyanellus

Longfin Dace Agosia chrysogaster

Rainbow Trout Oncorhynchus mykiss

Sonoran Sucker Catostomus insignis

Amphibians

Bullfrog Rana catesbeiana

Reptiles

Desert Grassland Whiptail Cnemidophorus uniparens

New Mexican Whiptail Cnemidophorus neomexicanus

Yarrow’s Spiny Lizard Sceloporus jarrovii

Birds

American Kestrel Falco sparverius

Black-Chinned Hummingbird Archilocus alexandri

Blue Grouse Dendragapus obscurus

Blue-Headed Vireo Vireo solitarius

Bronzed Cowbird Molothrus aeneus

Brown-Headed Cowbird Molothrus ater

Carolina Wren Thryothorus ludovicianus

Cassin’s Vireo Vireo cassinii

Cattle Egret Bubulcus ibis

Cowbird Molothrus spp.

Cuban Black-Hawk Buteogallus anthracinus gundlachii

Eastern Black Rail Laterallus jamaicensis jamaicensis

European Starling Sturnus vulgaris

Evening Grosbeak Coccothraustes vespertinus

Great Horned Owl Bubo virginianus

Greater Roadrunner Geococcyx californianus

Horned Lark Eremophila alpestris

House Sparrow Passer domesticus

Mangrove Black-Hawk Buteogallus subtilis

Meadowlark Sturnella spp.

Mourning Dove Zenaida macroura

Nighthawk Chordeiles spp.

Northern Mockingbird Mimus polyglottos

Pine Siskin Carduelis pinus

Ptarmigan Lagopus spp.

Purple Gallinule Porphyrula martinica

Purple Martin Progne subis

Ruffed Grouse Bonasa umbellus

Rufous Crab-Hawk Buteogallus aequinoctialis

Solitary Vireo Vireo solitarius

Southern Beardless-

 Tyrannulet Camptostoma obsoletum

Spruce Grouse Falcipennis canadensis

Stellar’s Jay Cyanocitta stelleri

Turkey Vulture Cathartes aura

Utila Black-Hawk Buteogallus subtilis utilensis

Western Kingbird Tyrannus verticalis

Western Meadowlark Sturnella neglecta

Yellow-Bellied Sapsucker Sphyrapicus varius

Yellow-Rumped Warbler Dendroica coronata
70 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Mammals

Abert’s Squirrel Sciurus aberti

Antelope Squirrel Ammospermophilus spp.

Bison Bison bison

Black-Tailed Jackrabbit Lepus californicus

Botta’s Pocket Gopher Thomomys bottae

Brush Mouse Peromyscus boylei

Cactus Mouse Peromyscus eremicus

Canada Lynx Lynx canadensis

Cottontail Sylvilagus spp.

Coyote Canis latrans

Deer Mouse Peromyscus maniculatus

Desert Pocket Mouse Perognathus penicillatus

Ground Squirrel Spermophilus spp.

Hare Lepus spp.

Hog-Nosed Skunk Conepatus mesoleucus

Jackrabbit Lepus spp.

Kangaroo Rat Dipodomys spp.

Little Brown Bat Myotis lucifugus

Merriam’s Kangaroo Rat Dipodomys merriami

Mountain Goat Oreamnos americanus

Nine-Banded Armadillo Dasypus novemcincus

Plains Pocket Gopher Geomys bursarius

Pocket Mouse Perognathus spp. or Chaetodipus spp.

Richardson’s Ground Squirrel Spermophilus richardsonii

San Joaquin Kit Fox Vulpes macrotis mutica

Spotted Ground Squirrel Spermophilus spilosoma

Striped Skunk Mephitis mephitis

White-Footed Mouse Peromyscus leucopus

White-Nosed Coati Nasua narica

White-Throated Woodrat Neotoma albigula

Woodrat Neotoma spp.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 71

Appendix F—Users Guide to the Species Account Database CD _________

The compact disc (CD) that accompanies this publication

contains all 305 species accounts in a searchable database

constructed in Microsoft (MS) Access. Two file formats are

available for viewing each individual account: Adobe PDF and

MS Word. Access to these files is regulated through the main

database, which has been designed to allow the user to search

for certain species or species groups, and to conduct queries

based on shared characteristics of the species accounts. (This

user’s guide is also provided on the CD in Adobe PDF format.)

System Requirements and Start Up

Use of this CD requires a MS Windows operating system

(Windows 2000 or later). The first time it is used, the CD will

download the database and associated files. If required, a

runtime version of Access 2003 and Adobe Acrobat Reader 7.0

will also download. However, a version of MS Word (2000 or

later) will need to be previously installed in order to view files

using the “Export to Word” function described below. (Note:

Local controls on the installation of software may make it

necessary to obtain local administrative rights in order to

download software from this CD.)

Installation of Database and Software

• Insert the CD into the computer’s CD-ROM drive.

• An on-screen, automated process will guide you through

the installation. Follow the instructions presented on the

screen to complete the installation. (Note: you will be

asked to select from a “Standard” or “Custom” installation; select the “Standard” option.)

• The CD will download under “Program Files” to a main

folder with the title “GTR-142 Species Accounts”. This

folder will also house subfolders that contain Adobe

Acrobat Reader 7.0, PDF Files, Word files, and Support

files. (In order for the database to function correctly, do

not alter the contents of these folders.)

Start Up of Database

Once the installation is complete, there are two ways to open

the database:

1. An icon will appear on the Windows desktop; doubleclicking on this icon will start the database.

2. The Windows “Start” button at the lower left corner of the

desktop allows you to access “Programs” and then a series

of subfolders. Move the cursor to “Programs,” then over

the main folder “GTR-142 Species Accounts.” Click on

the selection “GTR-142 Species Accounts” to start MS

Access and the database.

Viewing the User’s Guide

This User’s Guide is also available in Adobe PDF format for

on-screen viewing or printing. Follow the instructions above

for starting the database. To view the PDF version, follow the

instructions above for starting the database. Click on the lower

left button of the main screen (“User’s Guide”; see fig. F-1),

which will start Adobe Acrobat Reader 7.0 and open the User’s

Guide file.

Figure F-1.
72 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

Using the Database: Selecting

Species

Species accounts are accessed in three basic steps: (1) The

user instructs the database to generate a list of species of

interest, either by selecting certain species or species groups,

or by querying the accounts. (2) The database presents this list

of species on a screen titled “Display Requested Species,”

along with options as to the type of file you wish to view. (3)

The user selects which species to view and the desired viewing

format (Adobe PDF or MS Word files).

Generating a Search or Query

When the database is first opened, the main screen (fig. F-1)

will be displayed. Under the title panels, three bars provide

choices for (1) selecting species by common or scientific

name, (2) selecting species according to general taxonomic

groupings, legal status, or panel priority designations, and (3)

querying the entire database. (An additional “Exit” button

allows you to exit the program.)

Selecting Species by Common or Scientific Name—Click

on this bar to bring up a screen that gives you the option of

selecting either “common name” or “scientific name” of the

desired species. Species are presented in alphabetical order for

each. The common names are written using a left-to-right

convention of increasing specificity (for example: Owl, Sawwhet, Northern) in order to make it easier to find a species on

the list.

Click on each desired species name once to highlight the

name (remove a species by clicking a second time). When

finished, click the “Select Output” button in the lower right to

generate your list on the “Display Requested Species” screen.

(Otherwise, click the “Return to Main” button in the lower left

to return to the main screen.)

Selecting Species by Taxonomic Groupings, Legal Status, or Priority—This option opens the screen shown in figure

F-2. The two upper boxes allow you to generate a species list

based on taxonomic groupings (presented alphabetically).

Selections here may be made in either broad taxonomic categories (left menu) or more specific categories (right menu). Note

that while multiple selections can be made within each menu,

selections should be made from one or the other, but not both.

The broad categories are:

• Amphibians

• Birds

• Mammals

• Reptiles

The specific categories are:

• Bats

• Carnivores

• Ducks

• Frogs / Toads

• Heteromyid Rodents (Pocket Mice, Kangaroo Rats)

• Hummingbirds

• Lagomorphs

• Lizards / Skinks

Figure F-2.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005 73

• Marsh Birds / Shorebirds

• Misc. Non-Passerines (Caprimulgids, Pigeons, Trogons,

Cuckoos)

• Misc. Rodents (Beaver, Pocket Gophers, Jumping Mice)

• Murid Rodents (Mice, Rats, Voles, Muskrats)

• Passerines (Songbirds)

• Salamanders

• Sciurid Rodents (Squirrels, Chipmunks, Prairie-dogs,

Marmots)

• Shrews

• Snakes

• Turtles / Tortoises

• Ungulates

• Upland Game Birds

• Woodpeckers

Below these menus are boxes that allow choices based on

legal status and priority designation as presented in the species

accounts menus (see appendix B as well as the definitions

within the Species Account Guide). Selections can be made

from one or all of these menus, as well as with or without the

taxonomic selections above.

When your selections are complete, click the “Submit Search” button

to generate your list on the “Display Requested Species” screen, or

exit this screen by clicking the “Return to Main” button.

Query Terrestrial Species Accounts—This section allows

the user to query all accounts for shared menu selections as

well as for shared words or phrases within the text narratives.

Click on the bar on the main screen to initiate a query; the first

screen presented is titled “Terrestrial Species Account Query”

(fig. F-3).

This opening page explains that multiple query selections

can be made both within and between menus. One or more

choices (or none) may be highlighted in each menu on every

screen. Within a menu, the database will look for all species

that have at least one of the selections highlighted for the query

(similar to using an “OR” search operator); thus, more selections within a menu will result in a larger number of species

being returned. However, between menus (and narratives) the

database looks for species that contain all the highlighted

selections (similar to an “AND” search operator). Thus, including more menus or text narratives creates a more restrictive query and results in fewer species.

The query section presents all species account menus and

text narratives in the same sequence as the basic template

(appendix B) in a series of 9 pages. The menus and narratives

displayed on these pages are as follows:

• Page 1: Menus (2) - Distribution, Ecological Role

• Page 2: Narratives (5) - Status/Threats/Trends, Distribution, Breeding, Habitat, and Season of Use

• Page 3: Menus (3) - Season of Use, Specific Habitat

Associations, Important Habitat Functions

• Page 4: Menus (4) - Important Structural Features of

Habitat: Height

• Page 5: Menus (3) - Important Structural Features of

Habitat: Density

• Page 6: Menus (5) - Important Structural Features of

Habitat: Distribution; Tree/Saguaro Age; Elevation

• Page 7: Menus (5) - Other Important Habitat Features

• Page 8: Menus (2) - Diet Items, Grazing Impact Mechanisms; Narratives (2) - Diet, Grazing Effects

Figure F-3.
74 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-142. 2005

• Page 9: Narrative (1) - Fire Regime; Menus (4) - Fire

Regime Critically Important?, Fire Frequency, Fire Intensity, Fire Timing.

Using Keywords, Phrases—Queries within narratives require that the user enter a keyword or phrases to search for these

terms within that narrative only. The basic rules are as follows:

• Enter one word or multiple words separated by spaces

(that is, phrases); quotation marks are not required. The

database will search for and return all matches to whatever is typed within the query box.

• For shorter words, quotations, and bounding, spaces can

be utilized to prevent returns on fragments of larger

words. For example, a search on the word “red” will also

return any narrative with the words “tired”, “reduced”,

“redirect”, and so forth. In most cases, the user is actually

looking for the word “red” with spaces on either side. This

is solved by using quotation marks to type “red”. This

entry will return matches to only the word “red” without

any matching word fragments. Users may also wish to

conduct additional searches that use variations which

include trailing punctuation marks after the word (for

example, “red.”, “red,”, “red?”, “red;”, or “red:”) to

ensure that all occurrences of the word are captured by the

query.

Running the Query—At the bottom of each page are five

buttons for exiting the current screen: “Return to Main,”

“Return to Query,” “Previous Screen,” “Next Screen,” or “Go

To End.” Click on this last button (“Go To End”) when you

have finished entering all your query parameters. This will take

you to the last page, where this button is replaced by one

reading “Submit Search”; click here to generate your query list

on the “Display Requested Species” screen.

Using the Database: Viewing the

Species Accounts

After a search is generated, a screen titled “Display Requested Species” is shown that contains all species that fit the

criteria entered by the user, with scientific names followed by

common names (fig. F-4). Highlight all the species you wish

to view by clicking on the name once; remove by clicking the

name again. Once highlighted, the species accounts may be

viewed in two formats by clicking on one of the following two

buttons (a third button [“Return to Main”] returns you to the

main screen):

Preview PDF—This option will open Adobe Acrobat Reader

and present the species account in Adobe PDF format, which

can then be read on-screen or printed out.

Export to Word—This option opens the species account as

a MS Word file. This version can only be printed or read onscreen; it also allows the user to select specific text in the

account to “cut-and-paste” the information into another document. (Important: a version of MS Word 2000 or later is

required in order for this function to operate properly.)

Figure F-4.
Federal Recycling Program Printed on Recycled Paper
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its

programs and activities on the basis of race, color, national origin, age, disability,

and where applicable, sex, marital status, familial status, parental status, religion,

sexual orientation, genetic information, political beliefs, reprisal, or because all or

part of an individual’s income is derived from any public assistance program. (Not

all prohibited bases apply to all programs.) Persons with disabilities who require

alternative means for communication of program information (Braille, large print,

audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice

and TDD).

To file a complaint of discrimination, write to USDA, Director, Office of Civil

Rights, 1400 Independence Avenue, S.W., Washington, DC 20250-9410, or call

(800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity

provider and employer.

The Rocky Mountain Research Station develops scientific information and technology to improve management, protection, and use of

the forests and rangelands. Research is designed to meet the needs

of National Forest managers, Federal and State agencies, public and

private organizations, academic institutions, industry, and individuals.

Studies accelerate solutions to problems involving ecosystems,

range, forests, water, recreation, fire, resource inventory, land reclamation, community sustainability, forest engineering technology,

multiple use economics, wildlife and fish habitat, and forest insects

and diseases. Studies are conducted cooperatively, and applications

may be found worldwide.

Research Locations

Flagstaff, Arizona Reno, Nevada

Fort Collins, Colorado* Albuquerque, New Mexico

Boise, Idaho Rapid City, South Dakota

Moscow, Idaho Logan, Utah

Bozeman, Montana Ogden, Utah

Missoula, Montana Provo, Utah

*Station Headquarters, Natural Resources Research Center,

2150 Centre Avenue, Building A, Fort Collins, CO 80526

RMRS

ROCKY MOUNTAIN RESEARCH STATION