Colorado Mammal Catalog

Status Categories

Indigenous: occurs in an area through natural process without involvement of people.

IN: ext – extirpated; wild, self-sustaining populations eliminated so no longer living wild in Colorado

IN: ext - liv – extirpated but now kept as livestock

IN: mig – migratory; does not spend entire year within Colorado

IN: pio – pioneer; indigenous to North America but not to Colorado but expanding range through natural processes to establish a presence here

IN: res - mig – resident; local occurrence may vary with in-state seasonal migration

IN: res - sed – resident; no in-state seasonal migration so found in same area year round

IN: unk – unknown; status in state uncertain, requires more information

Exotic: “from another land,” meaning a species occurs in an area as a consequence of human involvement in geographic displacement, typically from another continent.

EX: liv – livestock; some portion of daily life needs acquired independently from the wild and some portion provided by human care

EX: est – established; surviving with a self-sustaining population

EX: fer – feral; not established but surviving only by ongoing releases or escapes

EX: his – historical; lived wild in the state since settlement times but not known to be surviving with a self-sustaining population

EX: pio – pioneer; originating as an exotic species outside Colorado but then expanding range through natural processes to arrive and establish a self-sustaining population here without direct human involvement

EX: sto – stocked; captured outside Colorado then released here for the purpose of establishing a wild, self-sustaining population

EX: unk – unknown; status in state uncertain, requires more information

American Name                                     Latin Name                                 Colorado Status

Armadillos                                                Dasypodidae

1      Armadillo, Nine-banded                      Dasypus novemcinctus                  IN: unk, pio

Bears                                                        Ursidae

        Bear, Black                                         Ursus americanus                         IN: res - sed

2      Bear, Grizzly                                       Ursus arctos                                  IN: ext

Beavers                                                    Castoridae

        Beaver, American                               Castor canadensis                         IN: res - sed

Jerboas                                                     Dipodidae

3      Jumping-Mouse, Meadow                   Zapus hudsonius                           IN: res - sed

        Jumping-Mouse, Western                    Zapus princeps                              IN: res - sed

Coypus                                                      Myocastoridae

4      Coypu                                                Myocastor coypus                         EX: his

Camels                                                      Camelidae

5      Llama                                                 Lama glama                                  EX: liv

Cats                                                          Felidae

        Bobcat                                                Lynx rufus                                     IN: res - sed

6      Cat, House                                         Felis silvestris                               EX: fer (est?)

7      Cougar                                               Puma concolor                              IN: res - sed

8      Lynx                                                   Lynx lynx                                      IN: res - sed

Cattles                                                      Bovidae

        Bison, American                                  Bison bison                                    IN: ext - liv

9      Cattle                                                  Bos taurus                                     EX: liv

10    Goat                                                   Capra hircus                                 EX: fer, liv

11    Mountain-Goat                                   Oreamnos americanus                  EX: sto

12    Sheep, Domestic                                 Ovis aries                                      EX: liv

        Sheep, Bighorn                                   Ovis canadensis                            IN: res - sto - mig

13    Yak                                                    Bos grunniens                                EX: liv

Deers                                                        Cervidae

        Deer, Mule                                         Odocoileus hemionus                    IN: res - mig

        Deer, White-tailed                               Odocoileus virginianus                 IN: res - mig, sed

        Elk                                                      Cervus elaphus                             IN: res - mig

14    Moose                                                Alces alces                                     IN: res - sto

Dogs                                                         Canidae

        Coyote                                               Canis latrans                                 IN: res - sed

15    Dog                                                    Canis familiaris                             EX: fer (est?)

        Fox, Gray                                           Urocyon cinereoargenteus            IN: res - sed

16    Fox, Kit                                              Vulpes macrotis                            IN: res - sed

        Fox, Red                                            Vulpes vulpes                                IN: res - sed

        Fox, Swift                                           Vulpes velox                                  IN: res - sed

17    Wolf, Gray                                          Canis lupus                                   IN: ext (pio?)

Evening-Bats                                            Vespertilionidae

Bat, Red                                             Lasiurus borealis                           IN: mig

        Bat, Hoary                                          Lasiurus cinereus                          IN: mig

        Bat, Silver-haired                                Lasionycteris noctivagans            IN: mig

        Bat, Big Brown                                   Eptesicus fuscus                            IN: res

18    Bat, Spotted                                       Euderma maculatum                    2 records

        Bat, Pallid                                           Antrozous pallidus                        IN: res

        Big-eared Bat, Townsend’s                 Plecotus townsendii                      IN: res - sed

        Myotis, California                                Myotis californicus                        IN: mig ?

        Myotis, Fringed                                   Myotis thysanodes                         IN: res - mig ?

        Myotis, Little Brown                           Myotis lucifugus                            IN: res

        Myotis, Long-eared                            Myotis evotis                                 IN: res ?

        Myotis, Long-legged                           Myotis volans                                IN: res ?

        Myotis, Yuma                                     Myotis yumanensis                        IN: res ?

        Myotis, Western Small-footed             Myotis ciliolabrum                        IN: res

19    Pipistrelle, Eastern                               Pipistrellus subflavus                    1 record

        Pipistrelle, Western                             Pipistrellus hesperus                     IN: res - sed

Freetail-Bats                                            Molossidae

20    Free-tailed Bat, Big                             Nyctinomops macrotis                  IN: mig

        Free-tailed Bat, Brazilian                     Tadarida brasiliensis                     IN: mig

Hedgehogs                                               Erinaceidae

21    Hedgehog, European                           Erinaceus europeus                       EX: his

Horses                                                      Equidae

22    Horse                                                 Equus caballus                              EX: est

Mice                                                         Cricetidae

        Cotton-Rat, Hispid                              Sigmodon hispidus                        IN: res - sed

        Grasshopper-Mouse, Northern           Onychomys leucogaster                IN: res - sed

        Harvest-Mouse, Plains                        Reithrodontomys montanus          IN: res - sed

        Harvest-Mouse, Western                    Reithrodontomys megalotis          IN: res - sed

        Mouse, Brush                                     Peromyscus boylii                         IN: res - sed

        Mouse, Canyon                                  Peromyscus crinitus                      IN: res - sed

        Mouse, Deer                                       Peromyscus maniculatus              IN: res - sed

        Mouse, Pinyon                                    Peromyscus truei                          IN: res - sed

        Mouse, White-footed                          Peromyscus leucopus                    IN: res - sed

        Rock-Mouse, Northern                       Peromyscus nasutus                      IN: res - sed

        Woodrat, Bushy-tailed                        Neotoma cinerea                           IN: res - sed

        Woodrat, Desert                                 Neotoma lepida                             IN: res - sed

        Woodrat, Eastern                                Neotoma floridana                        IN: res - sed

        Woodrat, Mexican                              Neotoma mexicana                       IN: res - sed

        Woodrat, Southern Plains                    Neotoma micropus                        IN: res - sed

        Woodrat, White-throated                    Neotoma albigula                         IN: res - sed

Moles                                                       Talpidae

        Mole, Eastern                                     Scalopus aquaticus                       IN: res - sed - (pio?)

Opossums                                                 Didelphidae

23    Mouse-Opossum                                Marmosa mexicana                      see notes

23    Mouse-Opossum                                Micoureus alstoni                          see notes

24    Opossum, Virginia                               Didelphis virginiana                      IN: pio

Pikas                                                         Ochotonidae

        Pika, American                                   Ochotona princeps                        IN: res - sed

Pocket-Gophers                                       Geomyidae

        Pocket-Gopher, Botta’s                      Thomomys bottae                         IN: res - sed

        Pocket-Gopher, Northern                   Thomomys talpoides                     IN: res - sed

        Pocket-Gopher, Plains                        Geomys bursarius                         IN: res - sed

        Pocket-Gopher, Yellow-faced            Cratogeomys castanops                IN: res - sed

Pocket-Mice                                             Heteromyidae

        Kangaroo-Rat, Ord’s                          Dipodomys ordii                            IN: res - sed

        Pocket-Mouse, Great Basin                Perognathus parvus                      IN: res - sed

        Pocket-Mouse, Hispid                        Chaetodipus hispidus                    IN: res - sed

        Pocket-Mouse, Olive-backed             Perognathus fasciatus                  IN: res - sed

        Pocket-Mouse, Plains                         Perognathus flavescens                IN: res - sed

        Pocket-Mouse, Silky                          Perognathus flavus                       IN: res - sed

Porcupines                                                Erethizontidae

        Porcupine                                           Erethizon dorsatum                      IN: res - sed

Pronghorns                                               Antilocapridae

25    Pronghorn                                           Antilocapra americana                 IN: res - mig, sed

Rabbits                                                     Leporidae

        Cottontail, Desert                                Sylvilagus audubonii                     IN: res - sed

        Cottontail, Eastern                               Sylvilagus floridanus                     IN: res - sed

        Cottontail, Mountain                            Sylvilagus nuttallii                        IN: res - sed

        Hare, Snowshoe                                 Lepus americanus                         IN: res - sed

        Jackrabbit, Black-tailed                       Lepus californicus                         IN: res - sed

        Jackrabbit, White-tailed                      Lepus townsendii                          IN: res - sed

Raccoons                                                  Procyonidae

        Raccoon                                             Procyon lotor                                IN: res - sed

        Ringtail                                                Bassariscus astutus                       IN: res - sed

Shrews                                                      Soricidae

        Shrew, Desert                                     Notiosorex crawfordii                   IN: res - sed

        Shrew, Dwarf                                     Sorex nanus                                  IN: res - sed

        Shrew, Elliot’s Short-tailed                  Blarina hylophaga                         IN: res - sed

        Shrew, Least                                       Cryptotis parva                             IN: res - sed

        Shrew, Masked                                  Sorex cinereus                               IN: res - sed

        Shrew, Merriam’s                               Sorex merriami                             IN: res - sed

        Shrew, Montane                                 Sorex monticolus                          IN: res - sed

26    Shrew, Preble’s                                  Sorex preblei                                 IN: res - sed

        Shrew, Pygmy                                     Sorex hoyi                                     IN: res - sed

        Shrew, Water                                     Sorex palustris                              IN: ukn

Skunks                                                      Mephitidae

27a  Hognose-Skunk, Common                  Conepatus mesoleucus                  IN: ukn, ext ?

27b  Skunk, Striped                                    Mephitis mephitis                          IN: res - sed

27c  Spotted-Skunk, Eastern                      Spilogale putorius                         IN: res - sed

27c  Spotted-Skunk, Western                     Spilogale gracilis                           IN: res - sed

Squirrels                                                   Sciuridae

28    Antelope-Squirrel, White-tailed           Ammospermophilus leucurus        IN: res - sed

29    Chickaree, Common                           Tamiasciurus hudsonicus              IN: res - sed

        Chipmunk, Cliff                                   Tamias dorsalis                             IN: res - sed

        Chipmunk, Least                                 Tamias minimus                            IN: res - sed

        Chipmunk, Colorado                           Tamias quadrivittatus                   IN: res - sed

        Chipmunk, Hopi                                  Tamias rufus                                 IN: res - sed

        Chipmunk, Uinta                                 Tamias umbrinus                          IN: res - sed

        Ground-Squirrel, Golden-mantled        Spermophilus lateralis                  IN: res - sed

30    Ground-Squirrel, Rock                        Spermophilus variegatus              IN: res - sed

        Ground-Squirrel, Spotted                    Spermophilus spilosoma               IN: res - sed

        Ground-Squirrel, Thirteen-lined           Spermophilus tridecemlineatus     IN: res - sed

31    Ground-Squirrel, Wyoming                 Spermophilus elegans                   IN: res - sed

        Marmot, Yellow-bellied                      Marmota flaviventris                    IN: res - sed

32    Squirrel, Tassel-eared                         Sciurus aberti                                IN: res - sed

        Squirrel, Fox                                       Sciurus niger                                 IN: pio, sto

33    Steppe-Squirrel, Black-tailed              Cynomys ludovicianus                  IN: res - sed

33    Steppe-Squirrel, Gunnison’s                Cynomys gunnisoni                       IN: res - sed

33    Steppe-Squirrel, White-tailed              Cynomys leucurus                         IN: res - sed

Voles                                                         Muridae

34    Mouse, House                                    Mus musculus                                EX: pio

        Muskrat, Common                              Ondatra zibethicus                        IN: res - sed

35    Rat, Brown                                         Rattus norvegicus                         EX: pio

        Vole, Heather                                     Phenacomys intermedius              IN: res - sed

        Vole, Long-tailed                                Microtus longicaudus                    IN: res - sed

        Vole, Meadow                                    Microtus pennsylvanicus               IN: res - sed

        Vole, Mexican                                    Microtus mexicanus                      IN: res - sed

        Vole, Montane                                    Microtus montanus                       IN: res - sed

        Vole, Prairie                                        Microtus ochrogaster                    IN: res - sed

        Vole, Sagebrush                                  Lemmiscus curtatus                      IN: res - sed

        Vole, Southern Red-backed                Clethrionomys gapperi                 IN: res - sed

Weasels                                                    Mustelidae

        Badger                                                Taxidea taxus                               IN: res - sed

36    Ferret, Black-footed                           Mustela nigripes                            IN: ext - sto

        Marten, American                               Martes americana                         IN: res - sed

37    Mink                                                   Mustela vison                                IN: res - sed - EX: est

38    Otter, River                                         Lutra canadensis                           IN: ext - sto

        Weasel, Short-tailed                            Mustela erminea                           IN: res - sed

        Weasel, Long-tailed                            Mustela frenata                             IN: res - sed

39    Wolverine                                           Gulo gulo                                      IN: ext

1      Nine-banded Armadillo — The species probably occurs in the state as lone individuals wandering.  However, a decade of warmer than average winter temperatures might favor a pulse of Armadillos wandering into Colorado from Oklahoma or Kansas.  Conversely, a decade of below average precipitation may disfavor them.  No reports of Armadillos in Colorado have been published since 1987.

2      Grizzly Bear —

3      Meadow Jumping-Mouse —

4      Coypu —

5      Llama —

6      House Cat —

7      Cougar —

8      Lynx —

9      Cattle —

10    Goat —

11    Mountain-Goat —

12    Domestic Sheep —

13    Yak —

14    Moose —

15    Dog — Genetics studies and other evidence from molecular biology strongly suggest a closer affinity to Gray Wolf than originally thought, so some mammalogists now treat the domestic Dog as the same species as the Gray Wolf, Canis lupus.  Many Dogs live as feral individuals, but evidence that indicates it has become established with a wild self-sustaining population is skimpy.  Cheri Jones studied and reported on feral Dogs breeding in Denver.

16    Kit Fox —

17    Gray Wolf —

18    Spotted Bat — The two records include a carcass found in Moffat County and a live bat found in Montezuma County.

19    Eastern Pipistrelle — Fitzgerald collected a specimen found on the side of a house in September 1987.  The specimen is now in the Denver Museum of Nature and Science.

20    Big Free-tailed Bat — Armstrong (1972) reported three records: 1 each from El Paso, Mesa, and Otero Counties.  Fitzgerald, Meaney, and Armstrong (1994) added single reports from Gunnison and Weld Counties.  Five reports in a century and a half of wildlife investigations suggests either the species is overlooked, somehow missed, or is indeed scarce as a wanderer after breeding season ends.

21    European Hedgehog — Edward Royal Warren reported (1942) that Gen. William J. Palmer imported European Hedgehogs and released them on his private estate near Colorado Springs.  Other Hedgehogs were released south of the Palmer Estate on Cheyenne mountain.  At least one European Hedgehog was subsequently captured in the Colorado Springs area.  Though the introduction failed and the species died out, the species must be included on a state mammal catalog.

22    Horse — As a species, the Horse occurs in Colorado as livestock animals, as pets, as work animals, and as wild animals in self-sustaining populations.  The wild populations have been undoubtedly established repeatedly from the early explorations of the Spanish into postsettlement times.

23    Mouse-Opossums —

24    Virginia Opossum — More cryptic here than in its Midwestern haunts, the Opossum undoubtedly availed anthropogenic modifications of the Great Plains and found its way westward across a landscape that had long been a barrier.  Individuals are occasionally seen in the foothills.

25    Pronghorn — The names “Antelope” and “Pronghorn Antelope” are gross misnomers and should not be used.  The Pronghorn was severely depleted in the late 1800s and early 1900s but was prioritized for recovery.  Its statewide population now numbers close to 100,000 by standardized estimates.

26    Preble’s Shrew — The single specimen was taken at Black Canyon of the Gunnison in 1966 but not reported as this species until 1992.

27    Skunks — Various features warrant separating the skunks from the weasel family and establishing them as their own family.

27a  The Common Hognose-Skunk was documented in Colorado only in the early Twentieth Century.  The Colorado Division of Wildlife notes in the species profile for “Skunk” on its website: “...No specimens have been reported in the past half-century, and the species may not live in Colorado now.”  Despite this admission, the species is incomprehensibly omitted from the Colorado list of species of special concern.

27b  No organization standardizes American names for mammals in the same manner as is done by the A.O.U. for birds and the A.F.S. for fishes.  In my own naming protocol, the genus with the most species assumes the base name for the family, and all other genus names are then hyphenated forms of this base name.  Under such a protocol, the striped skunk would become “striped-skunk.”  See the next note.

27c  Under my protocol, the genus Spilogale has the most species and would therefore assume the base name “skunk”; the modifier “spotted” would be dropped.  I have not yet elaborated this protocol in a publication; so until I do, I use both “spotted-skunk” as an American name equivalent of the genus Spilogale rather than the unhyphenated form and “hognose-skunk” as the American name equivalent of the genus Conepatus rather than the more orthographically awkward “hog-nosed skunk.”

28    White-tailed Antelope-Squirrel — Working from Note 25 regarding the Pronghorn, the name “antelope-squirrel” becomes a misnomer; but preserving the name as “pronghorn-squirrel” is likewise inappropriate, if not quirky.  An alternative will be offered in the future.  (See Notes 27b and 27c.)

29    Common Chickaree — On the basis of anatomy, morphology, and behavior, this animal and two relatives are classified into a separate genus (Tamiasciurus) discrete from the other arboreal squirrels (genus Sciurus).  To use the American name “Pine Squirrel” or “Red Squirrel” is to imply a closer biological relatedness than really exists.  Ergo, I prefer to use the name “chickaree” for this group.

30    Rock Ground-Squirrel — All species in the genus Spermophilus except this one bear the American name “ground-squirrel.”  The name usually given for this species is just “Rock Squirrel,” which falsely implies a closer relatedness to such arboreal squirrels as the Gray, Fox, and Tassel-eared while disregarding its true relatedness to Thirteen-lined, Wyoming, Spotted, and other ground-squirrels.  To correct this erroneous perception, I prefer to bring the American name into conformity with the standard for the genus and call it “Rock Ground-Squirrel.”

31    Wyoming Ground-Squirrel — Widely known as “Richardson’s Ground-Squirrel,” this species was segregated from Richardson’s more than a quarter-century ago.  Only the Wyoming Ground-Squirrel occurs in Colorado, yet books and environmental education programs continue to cite it as Richardson’s.

32    Tassel-eared Squirrel — Faced with alternative names that include one that is an eponym – a wildlife name based on a person’s name – and one that is not, I prefer to use the one that is not an eponym.  Conceived in an era of self-adulation, eponyms are a subtle form of nature-domination and an even subtler form of anthropomorphism, both equally inappropriate.

33    Steppe-Squirrels — The name “prairie dog” is egregious on two points: the animals are not dogs and they do not inhabit prairie.  They are, in fact, squirrels that inhabit the steppe, hence the name.

34    House Mouse — As a commensal of people, the House Mouse will live in modified landscapes that eliminate other voles and mice.  Consequently, it has become a vital prey species of urban-dwelling screech-owls.

35    Brown Rat — The species’ widely and popularly known name “Norway Rat” is inappropriate as a consequence of its now-global distribution.  The alternative name “Brown Rat” is becoming much more commonly used and will hopefully eclipse “Norway.”

36    Black-footed Ferret — Once present throughout Colorado’s plains, expansive mountain parks, and western valleys – essentially, wherever any of our three steppe-squirrel species lived – the Black-footed Ferret was extirpated certainly by the middle of the Twentieth Century.  A program that releases captive-reared Ferrets into the wild as a way to establish a self-sustaining population has been underway for several years.

37    Mink — Though indigenous to Colorado, the Mink was also ranched during the middle decades of the Twentieth Century.  When the market for Mink fur collapsed – if it ever really existed other than as a naively optimistic business venture – many captive Minks were released into the wild.

38    River Otter — After the River Otter’s extirpation became clear, it became a marquis species for recovery.  Otters were brought in from Canada and other places, but establishing a self-sustaining population proved more difficult than anticipated.  Today, River Otters occur in scattered localities around Colorado; but they may remain in an area for several years then completely disappear.