PO Box 9021, Wilmington, DE 19809, USA
E-mail: font@focusonnature.com
Phone: Toll-free in USA 1-888-721-3555
 or 302/529-1876

Website:  www.focusonnature.com


including those during
Focus On Nature Tours

and in nearby Kansas, 
Wyoming, Nebraska, 
& Oklahoma 

1993 thru 2015

during tours in the months of April and June/July

A cumulative list of Colorado Mammals compiled by Armas Hill 

UPPER RIGHT PHOTO:  BIGHORN SHEEP, in the Rocky Mountains of Colorado 


CO:  in Colorado
KS:  in Kansas
NE:  in Nebraska
OK:  in Oklahoma
WY:  in Wyoming

Links within this List:   Shrews    Rabbits & Allies     Porcupine     Beaver     

     Gophers, Woodrats, & Mice     Bats     Felines     Canines     Bear    

Raccoon & Ringtail     Mustelids     Pronghorn     Deer     Sheep     Bison

Other Links:

Upcoming North American Tour Itineraries, including those in Colorado & adjacent states  

A List & Photo Gallery of Birds in Colorado & Nearby States, in 2 parts:

Part #1:  Quails to Woodpeckers     Part #2:  Flycatchers to Buntings

Directory of Photos in this Website


  1. Virginia Opossum  (ph)  ______  (in far-eastern Colorado)
    Didelphis virginiana 


  2. Cinereus Shrew  ______  
    Sorex cinereus

  3. Water Shrew  ______  (in western Colorado)
    Sorex palistris

  4. Dwarf Shrew  ______
    Sorex nanus

  5. Merriam's Shrew  ______
    Sorex meriami

  6. Preble's Shrew  ______
    Sorex preblei

  7. Montane Shrew  ______
    Sorex monticolus

  8. Least Shrew  ______
    Cryptotis parva


  9. American Pika  ______ JUN/JUL CO  (also called "Cony")
    Ochotona princeps

  10. Snowshoe Hare ______ APR  CO,WY  (has also been called Varying Hare)
    Lepus americanus

  11. Black-tailed Jackrabbit  (ph)  ______ APR  CO,KS,OK
    Lepus californicus

    Black-tailed Jackrabbits 

  12. White-tailed Jackrabbit ______ APR JUN/JUL  CO,WY
    Lepus townsendii

  13. Desert Cottontail  (ph)  ______ APR JUN/JUL  CO
    Sylvilagus auduboni

    A Desert Cottontail

  14. Mountain Cottontail ______ APR JUN/JUL  CO,WY  (has also been called Nuttall's Cottontail)
    Sylvilagus nuttallii

  15. Eastern Cottontail ______ APR JUN/JUL  CO,KS,OK
    Sylvilagus floridanus


  16. North American Porcupine  (ph)  ______ APR  CO
    Erethizon dorsatum 
    (the single member of its genus)

    North American Porcupine
    (photo by Doris Potter)


  17. American Beaver  (ph)  ______ APR JUN/JUL  CO,WY
    Castor canadensis 

    American Beaver
    (photo by Doris Potter)

  18. Muskrat  (ph)  ______ APR JUN/JUL  CO,WY
    Ondatra zibethicus 
    (the single member of its genus)


  19. Yellow-bellied Marmot  (ph)  ______ APR JUN/JUL  CO
    Marmota flaviventris

    Yellow-bellied Marmot

  20. Black-tailed Prairie Dog ______ APR JUN/JUL   CO,KS,NE
    Cynomys ludovicianus 

  21. White-tailed Prairie Dog ______ APR JUN/JUL  CO
    Cynomys leucurus

  22. Gunnison's Prairie Dog  (ph)  ______  APR  CO
    Cynomys gunnisoni

    Gunnison's Prairie Dog
    (photo by Doris Potter)

  23. Thirteen-lined Ground-Squirrel ______ APR JUN/JUL  CO,WY
    (formerly Ictidomys) tridecemlineatus

  24. Wyoming Ground Squirrel  (was conspecific with Richardson's Ground Squirrel, Spermophilus richardsonii) ______ APR JUN/JUL  CO,WY
    Spermophilus elegans 

  25. Variegated Ground Squirrel  (ph)  ______ APR JUN/JUL  CO  (has also been called Rock Squirrel)
    (formerly Otospermophilus) variegatus

    A Rock Squirrel on a rock.
    The species is also called the Variegated Ground Squirrel.
    (photo by Doris Potter)

  26. Golden-mantled Ground Squirrel ______ APR JUN/JUL  CO
    (formerly Callospermophilus) lateralis

  27. American Red Squirrel ______ APR JUN/JUL  CO  (also called Chickaree)
    Tamiasciurus hudsonicus

  28. Least Chipmunk ______ APR JUN/JUL  CO
    (formerly Neotamias) minimus

  29. Colorado Chipmunk ______ APR JUN/JUL  CO
    (formerly Neotamias) quadrivittatus

  30. Unita Chipmunk  ______  
    Tamias umbrinus

  31. Hopi Chipmunk  (ph)  ______
    Tamias rufus

    Hopi Chipmunk
    (photo by Doris Potter)

  32. Abert's Squirrel (both black and gray morphs) ______ JUN/JUL  CO  (has also been called Tassel-eared Squirrel)
    (formerly Otosciurus) aberti

  33. Eastern Fox Squirrel (northern form) (ph)  ______ APR JUN/JUL  CO,NE
    Sciurus niger


  34. Northern Pocket Gopher  ______
    Thomomys talpoides

  35. Botta's Pocket Gopher  ______  (in far-southern Colorado)
    Thomomys bottae

  36. Yellow-faced Pocket Gopher  ______  (in southeastern Colorado)
    Cratogeomys castanops

  37. Plains Pocket Gopher  ______  (in eastern Colorado)
    Geomys bursarius

  38. Olive-backed Pocket Mouse ______ APR  CO
    Perognathus fasciatus

  39. Plains Pocket Mouse ______ APR  KS
    Perognathus flavescens

  40. Silky Pocket Mouse  ______
    Perognathus flavus

  41. Great Basin Pocket Mouse  ______  (in far-southwestern Colorado)
    Perognathus parvus

  42. Hispid Pocket Mouse  ______
    Chaetodipus hispidus

  43. Ord's Kangaroo Rat  ______
    Dipodomys ordii

  44. Meadow Jumping Mouse  ______  (in northern Colorado in mountains)
    Zapus hudsonius

  45. Western Jumping Mouse  ______
    Zapus princeps

  46. Eastern Woodrat  ______  (in eastern Colorado)
    Neotoma floridana

  47. Mexican Woodrat  ______
    Neotoma mexicana

  48. Southern Plains Woodrat  ______  (in southeastern Colorado)
    Neotoma micropus

  49. White-throated Woodrat  ______
    Neotoma albigula

  50. Bushy-tailed Woodrat  ______
    Neotoma cinerea

  51. Desert Woodrat  ______  (locally in far-western Colorado)
    Neotoma lepida

  52. Brown Rat  (i)  ______
    Rattus norvegicus

  53. Northern Grasshopper Mouse  ______
    Onychomys leucogaster

  54. Southern Grasshopper Mouse  ______
    Onychomys torridus   

  55. Plains Harvest Mouse ______ APR  CO
    Reithrodontomys montanus

  56. Western Harvest Mouse  ______
    Reithrodontomys megalotis

  57. White-fronted Deermouse  ______
    Peromyscus leucopus

  58. North American Deermouse  ______
    Peromyscus maniculatus

  59. Canyon Deermouse  ______  (locally in far-western Colorado)
    Peromyscus crinitus

  60. Pinon Deermouse  ______  
    Peromyscus truei

  61. Northern Rock Deermouse  ______
    Peromyscus nasutus

  62. Brush Deermouse  ______
    Peromyscus boylii

  63. Southern Red-backed Vole  ______
    Clethrionomys gapperi

  64. Montane Vole  ______
    Microtus montanus

  65. Long-tailed Vole  ______
    Microtus longicaudus

  66. Sagebrush Vole  ______  (in northwestern Colorado)
    Lemmiscus curtatus

  67. Western Heather Vole  ______  (in far-western Colorado)
    Phenacomys intermedius

  68. Prairie Vole  ______  (in eastern Colorado)
    Microtus ochrogaster

  69. Meadow Vole  (ph)  ______
    Microtus pennsylvanicus

    Meadow Vole
    (photo by Doris Potter)


  70. Mexican Free-tailed Bat  (ph)  ______
    Tadarida brasiliensis

  71. Eastern Red Bat  (ph)  ______  (in eastern Colorado)  
    Lasiurus borealis

    Eastern Red Bat
    (photo by Alan Brady)

  72. Hoary Bat  ______
    Lasiurus cinereus

  73. Silver-haired Bat  (ph)  ______
    Lasionycteris noctivagans

  74. Spotted Bat  ______  (in western Colorado)
    Euderma maculatum

  75. Townsend's Big-eared Bat  ______
    Corynorhinus townsendii

  76. Pallid Bat  ______
    Antrozous pallidus

  77. Fringed Myotis  ______
    Myotis thysanodes

  78. Long-eared Myotis  ______
    Myotis evotis

  79. California Myotis  ______  (in far-western Colorado)
    Myotis californicus

  80. Western Small-footed Myotis  ______
    Myotis ciliolabrum

  81. Long-legged Myotis  ______
    Myotis volans   

  82. Brown Myotis ______ JUN/JUL  CO  (has also been called Little Brown Bat)
    Myotis lucifugus

  83. Yuma Myotis  ______  (in far-southern Colorado)
    Myotis yumanensis

  84. Western Pipistrelle  ______
    Pipistrellus hesperus

  85. Big Brown Bat  ______
    Eptesicus fuscus


  86. Bobcat  (ph)  ______
    (formerly Lynx) rufus

  87. Canadian Lynx  ______  (in far-western Colorado)
    (formerly Lynx) canadensis

  88. Puma  (ph)  ______
    (formerly Puma) concolor


  89. Red Fox  (ph)  ______ APR  CO
    Vulpes fulva 
    (the North American animal is considered by some as conspecific with the Old World Red Fox, Vulpes vulpes


    Red Fox
    (photo by Howard Eskin)

  90. Swift Fox ______ APR JUN/JUL  CO
    Vulpes velox

  91. Kit Fox  ______  (in western Colorado)
    Vulpes macrotis

  92. Gray Fox ______ APR  CO
    Urocyon cinereoargenteus

  93. Coyote  (ph)  ______ APR JUN/JUL  CO,KS
    Canis latrans

    A Coyote photographed during a FONT tour


  94. Black Bear  ______
    Ursus americanus


  95. Northern Raccoon  (ph) ______ APR  CO
    Procyon lotor

  96. Ringtail  ______
    Bassariscus astutus 


  97. American Mink  (ph)  ______
    Mustela vison

  98. American Marten  ______
    Martes americana

  99. Wolverine  ______
    Gula gula

    A lone Wolverine that arrived in Colorado in early June 2011 was the first confirmed Wolverine in Colorado since 1919.

    Late the previous year, in December of 2010, and further north, biologists outfitted with a tracking collar a young Wolverine, as part of a reintroduction program. 
    That animal made a 500-mile journey from where it had been caught in the Grand Teton National Park in Wyoming. It was tracked as it crossed rugged terrain and some busy highways in Wyoming, from the Togwotee Pass to the Wind River Range and across sagebrush areas. The lone animal traveled until it crossed into Colorado on June 1. 

    The Wolverine reintroduction program, referred to here, began in 2001.   

    Most Wolverines live in Alaska and Canada. But formerly the animal did range in Idaho, Montana, Wyoming, Utah, Colorado, California, and Washington State.

    The Wolverine is one of the most elusive of mammals, a mysterious creature. It is known as being fearless and aggressive. It is strong, tenacious, sharp-toothed, and cunning. 
    Although adult Wolverines typically weigh about 30 pounds, they are stocky and "bear-like", and they prey on animals larger than they are. Even though the Wolverine is not a big animal, it is the largest land-dwelling member of the weasel family.

    Wolverines have evolved to require huge territories for roaming. A male's territory might be as much as 500 square miles, and he might share that landscape with 2 or 3 females that breed every other year, and usually produce a litter of two. Thus the species has a slow reproduction rate.

    Although a good survivor in nature, the Wolverine could not survive the trappers who prized its almost waterproof fur, and the ranchers who killed it with poison bait. So the animal pretty much vanished from the lower 48 states about a century ago. 
    The Wolverine in Colorado in 2011 was the first known to be in the state in 90 years. And, thus far, the only one.

  100. American Badger  (ph)  ______  APR  CO
    Taxidea taxus 
    (the single member of its genus)

    An American Badger photographed during a FONT April tour in Colorado

  101. Ermine  ______
    Mustela erminea

  102. Long-tailed Weasel  ______
    Mustela frenata

  103. Black-footed Ferret  ______
    Mustela nigripes

  104. Western Spotted Skunk ______ JUN/JUL  CO
    Spilogale gracilis 
    (was conspecific with what's now the Eastern Spotted Skunk, Spilogale putorius)

  105. Eastern Spotted Skunk  ______  (in far-eastern Colorado)
    Spilogale putorius

  106. Western Hog-nosed Skunk  ______
    Conepatus mesoleucus 

  107. Striped Skunk  (ph)  ______
    Mephitis mephitis


  108. Pronghorn ______ APR JUN/JUL  CO,KS,OK,WY
    Antilocapra americana 
    (the single member of its genus & family)

    Pronghorn, the only antelope in the Americas


  109. Elk (or Wapiti) ______ APR JUN/JUL  CO,WY
    Cervus elaphus canadensis 
    (another, slightly smaller, subspecies in Europe is called there the Red Deer

    Two photos of Elks.  ABOVE: a male, BELOW: a herd of females 
    (photos by Doris Potter)

  110. Moose ______ APR JUN/JUL  CO  (in Europe called the Elk)
    Alces alces 
    (the single member of its genus)

    Above & below: Moose
    In the lower photo, in Colorado, a female and a yearling male, mother and son  
    (upper photo by James Scheib; lower photo by Sally Brady)

  111. Mule Deer ______ APR JUN/JUL  CO,KS,OK,WY
    Odocoileus hemionus

  112. White-tailed Deer ______ APR JUN/JUL  CO,KS
    Odocoileus virginianus

    White-tailed Deer
    (photo by James Scheib)


  113. Bighorn Sheep ______ APR JUN/JUL  CO
    Ovis c. canadensis 
    (the subspecies of the central and northern Rockies)

    Bighorn Sheep photographed during a FONT tour in Colorado. 
    Notice the Black-billed Magpie on the back of one of the animals.
    Another Bighorn Sheep photograph is at the top of this list. 


  114. "Plains" Bison (or Buffalo) ______ APR JUN/JUL  CO  (today domesticated, the last wild Bison in Colorado was killed in 1889, in eastern CO)
    Bison b. bison

Some Notes:

Coyotes have expanded east across North America in the mid-1900's of wolves. Generally those in eastern North America tend to be larger than those in the American West. Those in the northern part of their range have longer and coarser fur. Coyotes travel in packs.   

The Bison (or Buffalo) is North America's largest present-day land mammal. It was, with the European settlement of America, nearly hunted to extinction. There were probably fewer than 1,000 animals remaining at the end of the 19th Century. The species "recovered" to about 150,000 animals by 1995, with 90% privately owned. They typically graze now in herds of 4 to 20.  

Reference for this mammal list is the new book: "Mammals of North America" by Roland W. Kays & Don E. Wilson, published by Princeton Univ Press, 2002.