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MAMMAL TECHNICAL COMMITTEE (MTC)

The Mammal Technical Committee was organized in 1979. A first contribution was "Chapter 6 - Mammals" in Species of Special Concern in Pennsylvania.

In 1989 the Mammal Technical Committee, along with the Ornithological Technical Committee, was designated byt he Pennsylvania Game Commission (PGC) as an official scientific advisory committee to the Commission. Under the terms of a Memorandum of Understanding between the Biological Survey and the PGC, representatives of these two technical committees and the Game Commission meet annually to discuss matters relating to the Commonwealth's mammals and birds.

Since publication of Species of Special Concern in Pennsylvania, the committee had undertaken a number of research initiatives, several of which were funded by grants from the Pennsylvania Wild Resource Conservation Fund. The results of two of these projects, a comprehensive assessment of the statuses of the mammals of Pennsylvania and a survey of the Statuses of Pennsylvania's cave-dwelling bats, were published in the Journal of the Pennsylvania Academy of Science. Other committee initiatives have included work on the statuses of solitary tree bats in southcentral and northern Pennsylvania, effeorts to determine the status of the least shrew (Cryptotis parva) in Pennsylvania, two years of survey work on small mammals of special concern in northeastern Pennsylvania, and a long-term project to monitor populations of the Allegheny woodrat (Neotoma magister) in Pennsylvania.

Porcupine

Members of the Mammals Technical Committee Are:

Click here to read "Learning the System" by mammalogist Janet Wright, and also find out who is on the Mammal Technical Committee.

Information about the distribution of Pennsylvania mammals also can be found at the Carnegie Museum. Please visit www.carnegiemnh.org/mammals/PAmamm/pamammals.html


MAMMALS: REVIEW OF STATUS IN PENNSYLVANIA

Janet Wright
Dickinson College

Gordon L. Kirkland, Jr.
Shippensburg University


MAMMAL STATUS

Seventy-one species of mammals are native to Pennsylvania. These represent 7 orders and 16 families (Appendix). As a group, mammals are only a small percentage of the state's native species of plants and animals. However, because mammals are familiar to so many citizens of Pennsylvania, they are important as symbols of the Commonwealth's native biological diversity.

Of the 71 native species, 11 appear to have been extirpated in historic times. Most of these are large mammals, including the gray wolf1, mountain lion, lynx, bison, wolverine, moose, and marten (Williams et al. 1985). Three other large species that were once extirpated -- the beaver, elk, river otter, and most recently, fisher -- have been successfully re-established. The only inconspicuous species that is presumed extirpated is the marsh rice rat.

Four species, or subspecies, of mammals are state-listed as Endangered within the Commonwealth: Northern flying squirrel, Indiana bat, Delmarva fox squirrel, and least shrew (Pennsylvania Game Commission 1995). Another 3 are state-listed as Threatened: eastern small-footed bat, West Virginia water shrew, and Allegheny woodrat. Both the Indiana bat and the Delmarva fox squirrel are also listed as Endangered under the Federal Endangered Species Act (Refer to chapter by J. D. Hassinger in the present volume for distinctions between Federal and state listings).

Despite the breadth of our knowledge of the mammals of Pennsylvania, a considerable amount of research remains to be done in order to ascertain the status and distribution of many species. These include Threatened and Endangered mammals, and those identified in a review by Kirkland and Krim (1990) as species or subspecies "at risk" or "status undetermined". This set includes the least weasel, the New England cottontail, several bat species, and the eastern spotted skunk.


EXOTIC SPECIES

Of the mammal species in Pennsylvania today, only 2 - Norway rat and house mouse - are exotic species. Two previously introduced species - the European hare and black rat - apparently are now extirpated (Doutt et al. 1973).


THREATS

Historically, the greatest threat to mammals in Pennsylvania was habitat destruction as Pennsylvanians tamed the wilderness during the 1800s and early 1900s. Unregulated hunting and trapping led to declines in the numbers of most larger mammals, including the majority of those now extirpated. Only the passage and enforcement of game laws provided the protection needed to prevent additional species from becoming extirpated.

Today, the greatest threat to mammals in Pennsylvania involves loss and degradation of habitat, especially for habitat specialists. When the habitat of a specialist is destroyed or degraded, the species may experience local declines. Continual loss of large numbers of habitat patches can lead to the extirpation or extinction of those species.

Bats provide a good example. Those social species that hibernate in caves and mines have very specific requirements for suitable hibernacula. These species tend to congregate in large numbers in relatively few sites. Destruction and degradation (including disturbance) of these hibernacula can have significant negative effects on the overall population levels of some bat species, such as the federally Endangered Indiana bat.

Human manipulation has indirect effects on mammals as well. For example, the use of long-lived insecticides on agricultural crops may lead to secondary poisoning of bats because of their dependence on flying insects. Wetland mammals such as the river otter and possibly the water shrew may have suffered both the direct effects of draining and channeling and the indirect effects of factors such as water pollution and reduction in cover or prey diversity (Kirkland and Serfass 1989).


INVENTORYING AND MONITORING

In the late 1940s, the Pennsylvania Game Commission undertook a major field survey of mammals throughout the Commonwealth, funded by the Pittman-Robertson project. The findings of the survey, submitted in a series of Game Commission reports (still available from the Pennsylvania Game Commission) and later summarized in a natural history volume by Doutt et al. (1973), formed the first systematic report on the geographic distribution and status of mammals of Pennsylvania. Nothing of the scope of the mammal survey has been attempted since. Instead, there have been numerous special-purpose inventories and some specialized long-term projects. Potentially, these data are extremely valuable for addressing questions of biodiversity. To a great extent, however, this potential has been untapped. To understand the problem, and to envision the solution, it is helpful to consider the ways that mammal data have been collected and recorded in the Commonwealth in the past several decades.


PUBLISHED MAMMAL INVENTORIES

Perhaps the most accessible mammal diversity data came from Pennsylvania mammal studies that have been reported in the scientific literature. Examples are surveys of all mammal species at one time period and a specific locality, such as a state park or natural area (Brown and Ropski 1995). Although limited in scope, such "snapshot" surveys allow concrete statements about mammal diversity at a particular place and time, for comparison to other locations or times. A few published studies have explored the relationship between mammal diversity and particular disturbance such as clearcutting, forest fragmentation, and other land alterations (Kirkland 1978, Mastrota et al. 1990, Yahner 1992, Storm et al. 1993, McCay and Storm 1997). These not only list species for particular localities but also provide a basis for predictions about biodiversity elsewhere in the face of similar disturbance.

Despite the fact that scientific literature can be retrieved by anyone, the information in these reports may not readily lend itself to other applications, because the raw data are seldom included. One report may give a species list without abundance data, another may give only a relative measure of abundance such as catch-per-unit-effort, and a third may report a quantitative diversity index without listing species. From these disparate formats it may be impossible to re-compile the data in a meaningful way to develop an overall picture of biodiversity.


MAMMAL COLLECTIONS

Less readily accessible to the public, yet still in the form of official, institutional records, are mammal data from museum collections. Although several museum collections of mammals have existed historically in Pennsylvania, only 2 collections are actively curated now, one at the Vertebrate Museum of Shippensburg University and the other at the Carnegie Museum of Natural History. Both are designated repositories for specimens for the Pennsylvania Game Commission, but only the Shippensburg Museum routinely accepts new Pennsylvania specimens. The Carnegie houses approximately 25,000 specimens of Pennsylvania mammals, and Shippensburg approximately 13,000. Most of these are preserved as skins and skulls; smaller numbers are skeletons or preserved in fluid. The mammal collection of the Carnegie Museum also has some frozen tissue specimens, plus records for Pennsylvania specimens housed in museums outside the state.

From a biodiversity standpoint, museum collections are irreplaceable "reference libraries" of the actual biological material required to plot geographic variation and changes through time, and to identify new specimens precisely. Appropriately preserved and documented, museum specimens can also be used for studies of reproduction, food habits, and exposure to toxins. The precise locality and date recorded for each specimen can allow detailed mapping of species occurrence in particular time periods. All these uses would greatly aid biodiversity planning in Pennsylvania. Currently, however, museum data are used much less than they could be. Although most records for both collections are computerized, they are generally released only upon specific approved request. Most of the locality data have yet to be converted to latitude-longitude coordinates for use by computerized mapping systems. There are concerns that information might be abused, for example to locate rare species for unauthorized collecting, if access to the data is unrestricted. These are obstacles faced by museum collections nationwide, and solutions are being worked out in other states. Pennsylvania's 2 major mammal collections need to be part of these discussions and need to acquire the resources to make their extremely valuable data available for research and decision making.


GAME COMMISSION DATA

Another large set of mammal inventory and monitoring data resides in databases held by the Wildlife Management Bureau of the Pennsylvania Game Commission (PGC). The Wildlife Diversity Branch of this Bureau has been very active in recent years in compiling databases relevant to species of special concern. A Bat Hibernaculum Survey contains estimated species counts from major bat wintering sites since the mid 1980s. A Bat Summer Breeding Colony survey, and a Bat House database to document the success of PGC artificial bat houses, have existed since the early 1990s. An Allegheny woodrat database contains assessments of woodrat status at over 500 sites statewide, based on direct observation by PGC personnel. A terrestrial mammal database contains research data collected by the PGC for special-status species other than bats. Besides these databases for non-game species, the PGC compiles a number of other data sets including data for tagged bears, road kill reports of selected furbearers, an annual ground survey of beaver populations by field personnel, and radio-tracking records for reintroduced otter and fisher.

Though organized various ways and for different initial purposes, all the PGC surveys are based on original records (that is, records for individual specimens with specific locality and date) and are potentially valuable for our understanding of biodiversity. Most of these records have been entered into computer files. They are available by request in hard copy, but they are not yet accessible on-line, and there is no central repository or standard format that would allow them to be coordinated. As a result, their use is very restricted. PGC data represent a large public-fund investment in the mammal fauna of the Commonwealth, and a large interest in the status of mammals. Making these data more accessible for biodiversity analysis should be a high-priority goal.


THE PENNSYLVANIA NATURAL DIVERSITY INVENTORY AND CENTRALIZED DATA MAINTENANCE

Yet another repository for mammal inventorying and monitoring data is the Pennsylvania Natural Diversity Inventory (PNDI). Mammal records represent only a small fraction of the PNDI's database, but at least some of the PGC's records (such as the Allegheny woodrat database) are periodically incorporated into PNDI. Because of format differences, data shared in this way must be re-entered by hand. Data-entry backlogs, and emphasis on species of concern rather than all species, hamper PNDI's usefulness as a biodiversity resource. Although PNDI's structure (a partnership among the Bureau of Forestry of the Department of Conservation and Natural Resources, The Nature Conservancy, and the Western Pennsylvania Conservancy) is peculiar to Pennsylvania, its database is analogous to Heritage databases in other states. Some of these have on-line access for approved subscribers. The PNDI is not currently operating on a scale to provide that service, but it is the most logical organization to do so. Resources should be provided to allow PNDI to act as the central clearinghouse for mammal biodiversity records from PGC and other sources, with the goal of having both entry and access of data as on-line processes. In addition to scientific literature, museum collection, Game Commission, and PNDI databases, other monitoring and inventory data for Pennsylvania mammals exist in various places. Various national parks and the Allegheny National Forest keep their own mammal occurrence data. Powdermill Nature Reserve, of the Carnegie Museum of Natural History, has a data set for small mammal dynamics in relation to environmental variables that spans 18 years and includes 38,000 entries (J. Merritt, pers. comm.). Mammalogists at academic institutions have their own research data. A central, internet-accessible PNDI would act as a magnet for such data. Most agencies and researchers would be eager to have their data receive wider use in support of biodiversity conservation. The main necessary step to take is to make the coordination simple and convenient -- that is, put it on-line.

A centralized database for mammal inventory and monitoring data would have many uses, but 2 projects illustrate its potential. One major project now in progress among ornithologists is the Important Bird Areas Project, initiated by the National Audubon Society and coordinated in Pennsylvania by the Ornithological Technical Committee (OTC) of the Pennsylvania Biological Survey. The Important Bird Areas Project seeks to identify public and private sites of special value for bird diversity, both to promote their conservation and to make wider appropriate use of these sites. In designating Important Bird Areas, the OTC is able to draw on excellent databases from Christmas bird counts, breeding bird surveys, and the like (see chapter by D. A. Gross in the present volume). The OTC's counterpart, the Mammal Technical Committee (MTC), has been developing plans for an Important Mammal Areas Project with similar goals, but MTC lacks the rich data resources to aid in selecting Important Mammal Areas. The choice of these areas must at this point rest on more anecdotal information. A centralized biodiversity database could make this project more solidly based and much simpler to conduct.

A second project being developed within the Pennsylvania Biological Survey is a Biodiversity Monitoring Network for Pennsylvania. The general plan for this network is to designate a set of monitoring sites that will be sampled annually, at several taxonomic levels and with standardized protocols, by teams of students supervised by college-level instructors or other professionals. With careful choice of sites and sampling protocols, the data from this network would reveal long-term biodiversity trends and would be the basis for biodiversity decisions statewide. A centralized biodiversity database not only would make the choice of sites and species to sample much more straightforward, but such a database will be essential as a repository for the data that result from the monitoring.

Fortunately, Pennsylvania mammalogists and conservationists need not start from scratch to solve the problems of centralizing their biodiversity data. Efforts are already under way at the national level to coordinate and standardize the many sorts of ecological data collected at biological field stations and long-term ecological study sites (Michener et al. 1996). The National Center for Environmental Analysis and Synthesis (NCEAS), based at the University of California, Santa Barbara, plans to act as an organizational body for such data. Guidelines being developed at the national level should be an important ingredient in Pennsylvania's coordination of mammal biodiversity data.


SUMMARY

Compared to other taxonomic groups, the status of most mammal species in Pennsylvania can be relatively well understood with data that already exist. There are some inventorying gaps to fill, and it will be important to continue monitoring both overall mammal diversity and the dynamics of select species in relation to environmental variables. Immediately, however, a very high priority for mammal biodiversity is to preserve, coordinate, and make accessible the valuable information hidden away in agency and research databases, the PNDI, and our major museum collections. Current efforts by the Pennsylvania Biological Survey, including the Important Mammal Areas Project and a developing Biodiversity Monitoring Network, highlight the importance of accessible databases. With increasing consensus about the importance of such resources, and newly emerging practical guidelines to build them, there is good reason to be optimistic about the stewardship of mammal biodiversity in Pennsylvania's future.


REFERENCES

Brown, E., and S.J. Ropski. 1995. A survey of the mammals of the Wattsburg Fen Natural Area and the Titus Bog Preserve. J. Pa. Acad. Sci. 69:111-114.

Doutt, J. K., C. A. Heppenstall, and J. E. Guilday. 1973. Mammals of Pennsylvania, Third ed. Pennsylvania Game Comm., Harrisburg, Pa.

Genoways, H. H. and F. J. Brenner, ed. 1985. Species of special concern in Pennsylvania. Special Publication Number 11, Carnegie Mus. of Natural History.

Gifford, C. L., and R. Whitebread. 1951. Mammal survey of south central Pennsylvania. Pennsylvania Game Commission, Harrisburg, Pa. 67pp.

Grimm, W. C., and H. A. Roberts. 1950. Mammal survey of southwestern Pennsylvania. Pennsylvania Game Comm., Harrisburg, Pa. 99pp.

Grimm, W. C., and R. Whitebread. 1952. Mammal survey of northeastern Pennsylvania. Pennsylvania Game Comm., Harrisburg, Pa. 82pp.

Kirkland, G. L., Jr. 1978. Initial responses of small mammals to clearcutting of Pennsylvania hardwood forests. Proc. Pa. Acad. Sci., 52:21-23.

Kirkland, G. L., Jr. 1986. Small mammal species of special concern in Pennsylvania and adjacent states: an overview. Pages 252-267 in S. K. Majumdar, F. J. Brenner, and A. F. Rhoads, eds. Endangered and Threatened Species Programs in Pennsylvania and other States: Causes, Issues, and Management. Pa. Acad. Sci., Easton, Pa.

Kirkland, G. L., Jr., and P. M. Krim. 1990. Survey of the statuses of the mammals of Pennsylvania. J. Pa. Acad. Sci., 64:33-45.

Kirkland, G. L., Jr., and T. L. Serfass. 1989. Wetland mammals of Pennsylvania. Pages 216-230 in S. K. Majumdar, R. B. Brooks, F. J. Brenner, and R. W. Tiner, Jr., eds. Wetlands Ecology and Conservation: Emphasis in Pennsylvania. Pa. Acad. Sci., Easton, Pa.

Mastrota, F. N., R. H. Yahner, and G. L. Storm. 1990. Autumnal microhabitat use by small mammals in a mixed-oak forest irrigated with wastewater in central Pennsylvania. J. Pa. Acad. Sci. 64:73-77.

McCay, T. S., and G. L. Storm. 1997. Masked shrew (Sorex cinereus) abundance, diet and prey selection in an irrigated forest. Am. Midl. Nat. 138:268-275.

Merritt, J. F. 1987. Guide to the mammals of Pennsylvania. Univ. of Pittsburgh Press, Pittsburgh, Pa.

Michener, W. K., J. W. Brunt, J. J. Helly, T. B. Kirchner, and S. G. Stafford. 1997. Nongeospatial metadata for the ecological sciences. Ecol. Applic. 71:330-342.

Pennsylvania Game Commission. 1995. Endangered and Threatened species of Pennsylvania. Pennsylvania Game Comm., Harrisburg, Pa.

Richmond, N. D., and H. R. Roslund. 1949. Mammal survey of northwestern Pennsylvania. Pennsylvania Game Comm., Harrisburg, Pa. 67pp.

Roberts, H. A., and R. C. Early. 1952. Mammal survey of southeastern

Pennsylvania. Pennsylvania Game Comm., Harrisburg, Pa. 70pp.

Roslund, R. 1951. Mammal survey of northcentral Pennsylvania. Pennsylvania Game Comm., Harrisburg, Pa. 55pp.

Storm, G. L., R. H. Yahner, and E. D. Bellis. 1993. Vertebrate abundance and wildlife habitat suitability near the Palmerton zinc smelters, Pennsylvania. Arch. Environ. Contam. Toxicol. 25:428-437.

Thorne, S. G., K. C. Kim, K. C. Stiener (co-directors), and B. J. McGuinness (editor). 1995. A Heritage for the 21st century: Conserving Pennsylvania's native biological diversity. Pennsylvania Fish & Boat Comm., Harrisburg, Pa.

Williams, S. L., S. B. McLaren, and M. A. Burgwin. 1985. Paleo-archaeological and historical records of selected Pennsylvania mammals. Ann. Carnegie Mus. 54:77-188.

Yahner, R. H. 1992. Dynamics of a small mammal community in a fragmented forest. The Am. Midl. Nat. 127:381-391.

Appendix. Mammal Checklist

         
     

Status

Habitat

Behavior

Marsupials: Marsupialia

         

new world opossums: Didelphidae

   

C

G

N,C

 

Virginia opossum, Didelphis virginiana

       

Insectivores: Insectivora

         

shrews: Soricidae

         
 

masked shrew, Sorex cinereus

 

C

M,B,

N,C

 

water shrew, Sorex palustris

 

R,T

M,S

A

 

smokey shrew, Sorex fumeus

 

C

M

A

 

long-tailed shrew, Sorex dipar

 

I

M,R

U

 

pygmy shrew, Sorex hoyi

 

S

G

A

 

northern short-tailed shrew, Blarina brevicauda

 

C

G

A

 

least shrew, Cryptotis parva

 

E

A,N

A

moles: Talpidae

         
 

hairy-tailed mole, Parascalops breweri

 

C

G

A,Y

 

eastern mole, Scalopus aquaticus

 

C

G,R

A,Y

 

star-nosed mole, Condylura cristata

 

C

W,S

A,Y

bats: Chiroptera

         
 

plain-nosed bats: Vespertilionidae

       
   

little brown bat, Myotis licifugus

C

C,S

H

   

long-eared bat, Myotis keenii

R

C,S

H

   

pink-faced bat, Myotis sodalis

E

C,S

H

   

small-footed bat, Myotis leibii

T

C,S

H

   

silver-haired bat, Lasionycteris noctivagans

R

X

M

   

eastern pipistrelle, Pipistrellus pipistrellus

S

C,S

H

   

big brown bat, Eptesicus fuscus

C

C

H

   

red bat, Lasiurus borealis

U

X

M

   

hoary bat, Lasiurus cinereus

U

X

M

   

evening bat, Nycticeius humeralis

R

G

T,H

   

Seminole bat, Lasiurus seminolus

U

?

Y

lagomorphs: Lagomorpha

         
 

rabbits and hares: Leporidae

       
   

eastern cottontail, Sylvilagus floridanus

C

B,G

A,C,Y

   

New England cottontail, Sylvilagus transitionalis

A

M

U,Y

   

snowshoe hare, Lepus americanus

A

M

N,Y

rodents: Rodentia

         
 

squirrels: Sciuridae

       
   

eastern chipmunk, Tamias straitus

C

G

D,H

   

woodchuck, Marmota monax

C

W,A,R

D,H

   

gray squirrel, Sciurus carolinensis

C

D,G

D,T

   

fox squirrel, Sciurus niger

R,E,C

D,A

D,T

   

red squirrel, Tamiasciurus hudsonicus

C

D,X

D,T

   

southern flying squirrel, Glaucomys volans

C

D,X

N,T

   

northern flying squirrel, Glaucomys sabrinus

E

X,C

N,T

 

beavers: Castoridae

       
   

beaver, Castor canadensis

C

S,L

N,Y

 

native rats, mice, and voles: Cricetidae

       
   

rice rat, Oryzomys palustris

I

M,A

N,Y

   

deer mouse, Peromyscus maniculatus

C

G

N

   

white-footed mouse, Peromyscus leucopus

C

G

N

   

eastern woodrat, Neotoma magister

T

M,R

N

   

southern red-backed vole, Clethrionomys gapperi

C

X,C,R

N

   

meadow vole, Microtus pennsylvanicus

C

N,W

A,Y

   

rock vole, Mictotus chrotorrhinus

A

X,R

D,Y

   

pine vole, Microtus pinetorum

C

G

A,Y

   

southern bog lemming, Synaptomys cooperi

I

N,W

A,Y

   

muskrat, Ondatra zibethicus

C

W,L,S

N

 

old world rats and mice: Muridae

       
   

Norway rat, Rattus norvegicus

C

H,A

N

   

house mouse, Mus musculus

C

H,A

H

 

jumping mice: Zapodidae

       
   

meadow jumping mouse, Zapus hudsonius

C

N,S

H,N

   

woodland jumping mouse, Napeozapus insignis

C

M,C,

H,N,C

 

new world porcupines: Erethizontidae

       
   

porcupine, Erethizon dorsatum

C

M,C,

N,Y

carnivores: Carnivora

         
 

dogs and foxes: Canidae

       
   

eastern coyote, Canis latrans

S

G

A

   

red fox, Vulpes vulpes

C

B, A

N

   

gray Fox, Urocyon cinerecargenteus

C

B,D

N

 

bears: Ursidae

       
   

black bear, Ursus americanus

C

M,C,D

N

 

raccoons: Procyonidae

       
   

raccoon, Procyon lotor

C

G

N

 

weasels, skunks, and otters: Mustelidae

       
   

ermine, Mustela erminea

I

B,A

N

   

least weasel, Mustela nivalis

U

B,A

N

   

long-tailed weasel, Mustela frenata

C

G?

N

   

mink, Mustela vison

C

W,S

C

   

eastern spotted skunk, Spilogale putorius

E

R,X

D

   

striped skunk, Mephitis mephitis

C

G

N

   

river otter, Lutra canadensis

C

G

C,A

 

cats: Felidae

       
   

bobcat, Felis rufus

A

M,B,A, R

N

even-toed hoofed mammals: Artiodactyla

         
 

deer: Cervidae

       
   

white-tailed deer, Odocoileus virginianus

C

G

C,A


Occassional/Questionable Occurrences

    carnivores: Carnivora

        weasels, skunks, and otters: Mustelidae

            marten, Martes americana

            fisher, Martes pennanti

    cats: Felidae

            mountain lion, Felis concolor

            lynx, Felis lynx


Extirpated Species

    carnivores: Carnivora

        dogs and foxes: Canidae

            grey wolf, Canis lupus

        weasels, skunks, and otters: Mustelidae

            wolverine, Gulo gulo

    even-toed hoofed mammals: Artiodactyla

        deer: Cervidae

            elk, Cervus elaphus

            moose, Alces alces

        bovines: Bovidae

            bison, Bison bison

This checklist was designed to serve as both a guide to students and the public and is intended to provide an overview of the general characteristics and current status of all mammal species occurring within the Commonwealth, including those that have been introduced or eliminated within the State boundaries. Both the common and scientific names are provided for each species, followed by abbreviations of current status, preferred habitat, and general behavior. Abbreviations are defined below. NOTE: The eastern elk subspecies, native to Pennsylvania, was extirpated in the early 1900s. However, the Rocky Mountain subspecies was re-introduced in the Commonwealth from western states. The fisher has also been re-introduced into Pennsylvania.


Status: Status of all species is based on the work of Kirkland and Krim (1990; see also, Genoways and Brenner, 1985). Those species not considered of special concern are listed as either C(Common), I(restricted distribution), or S(secure now, but previously listed as Species of Concern). Multiple designations refer to subspecies status. The following six categories have been recognized for species of special concern by the Pennsylvania Biological Survey. However, the reader should refer to the chapter by J. D. Hassinger in the present volume for more details concerning classifications.

U(Undetermined) - Species of concern for which insufficient data are available for adequate assessment

R(Rare) - Species found in either a few restricted areas or over a broad area at low numbers

A(At Risk) - Species particularly vulnerable to further habitat modifications or exploitation

T(Threatened) - Species that are likely to become Endangered within the foreseeable future

E(Endangered) - Species of imminent danger of extinction in Pennsylvania

X(Extirpated) - Species that disappeared from Pennsylvania since 1600


Habitats: Behavior:

M - mountain woodlands N - nocturnal (active at night)

R - rocky areas D - diurnal (active in day)

B - brush thickets, hedgerows C - crepuscular (active at dawn and dusk)

W - marshes A - active day and night

S - streams, rivers T - nests in tree hollows

L - lakes, ponds M - migratory

N - grasslands H - hibernator

C - coniferous forests Y - active year-round

D - deciduous forests

X - mixed forests

A - agricultural lands, old fields

H - near human/suburban areas (barns, attics)

G - generalized habitat requirements (found in a variety of habitats)

See Appendix for scientific names.