Mammals

Yellowstone is home to the largest concentration of mammals in the lower 48 states. In addition to having a diversity of small animals, Yellowstone is notable for its predator–prey complex of large mammals, including eight ungulate species (bighorn sheep, bison, elk, moose, mountain goats, mule deer, pronghorn, and white-tailed deer) and seven large predators (black bears, Canada lynx, coyotes, grizzly bears, mountain lions, wolverines, and wolves).

The National Park Service’s goal is to maintain the ecological processes that sustain these mammals and their habitats while monitoring the changes taking place in their populations. Seasonal or migratory movements take many species across the park boundary where they are subject to different management policies and uses of land by humans.

Understanding the links between climate change and these drivers will be critical to informing the ecology and management of Yellowstone’s wildlife in the years to come.

 
 

Carnivores (Order Carnivora)

Carnivores all started out as meat-eaters, but many have evolved to be omnivores (consumers of plants and animals). Over a dozen carnivores can be found within the park.

 
The white-and-black striped head of a badger.

Badger

Borrowing predators of small rodents.

An adult black bear and cub stand in grass near a forest

Black Bear

Black bears are commonly seen in Yellowstone.

A bobcat walking through a snowy field of brush.

Bobcat

One of the elusive cats of Yellowstone.

A lynx along a snowy river bank.

Canada Lynx

Lynx are one of three cat species found in Yellowstone.

A male cougar stalking across a patch of snow.

Cougar

Largest of the cat species in Yellowstone.

A canine with large pointy ears looks at the camera

Coyote

Coyotes are abundant throughout the park.

A grizzly bear in a meadow near Swan Lake

Grizzly Bears

Learn about the biology of this top predator.

A reddish-brown long-tailed weasel hopping across a road.

Long-tailed Weasel

Long-tailed weasels change color based on the season.

A reddish-brown marten up in a conifer tree.

Marten

Member of the weasel family that lives in woodlands.

A red fox staring across a snowy field.

Red Fox

Smallest of the three canid species found in the park.

Four river otters resting on a snowy river bank.

River Otter

The most aquatic of the weasels in the park.

A short-tailed weasel looks back over its shoulder.

Short-tailed Weasel

Small weasels also known as ermine.

A wolverine looks around a snowy field.

Wolverine

A mid-size carnivore in the weasel family.

A black and dark gray wolf in snow

Wolves

Gray wolves were restored in 1995.

 

Ungulates (Order Artiodactyla)

Ungulates are hooved herbivores (plant-eaters), and there are two types: even-toed and odd-toed. All of the native ungulates found in Yellowstone are even-toed, while there is one odd-toed ungulate you may see in the park: horses.

 
A large bull bison stands on a hill covered in some snow backed by blue sky

Bison

Yellowstone bison exhibit behavior like their ancient ancestors.

Profile of a bighorn sheep with curled horns

Bighorn Sheep

Most bighorn sheep in Yellowstone are migratory.

A bull elk with large antlers bugles in front of yellow leaves

Elk

Elk are the most abundant large mammal found in Yellowstone.

A moose without antlers lays on grass as a wet calf nuzzles its nose

Moose

Moose are the largest members of the deer family in Yellowstone.

Two mountain goats standing upon a rock pinnacle.

Mountain Goat

Mountain goats are considered non-native species.

A mule deer buck in the springtime.

Mule Deer

Also called blacktail deer, they are an exclusively western species.

A pronghorn looking directly at the camera.

Pronghorn

The surviving member of a group of animals that evolved in North America during the past 20 million years.

Two white-tailed deer browsing in the park.

White-tailed Deer

A common deer on the East Coast, they are scarcely seen in Yellowstone.

 

Rodents (Order Rodentia)

Rodents are a vital part of the ecosystems in Yellowstone, serving as a major food source for many of the park's predators. All rodents have a pair of incisors in their upper and lower jaws with a large gap between the incisors and the molars. The incisors continue to grow throughout their lives, so they continually wear them down through chewing.

 
Beaver sliding into the water

Beaver

Beaver affects habitat structure and dynamics through the damming and diverting of streams.

Two golden-mantled ground squirrels on a log.

Golden-mantled Ground Squirrel

Found throughout Yellowstone, they are often mistaken as chipmunks.

Least chipmunks eating seeds.

Least Chipmunk

Least chipmunks are commonly seen around the park.

A small, gray vole amongst yellow grass and dried leaves.

Montane Vole

Perhaps the most important prey species in the park.

Close-up of a pocket gopher's face and digging claws.

Pocket Gopher

Very active burrowing rodents.

A red squirrel sits in a tree with a cone.

Red Squirrel

Common woodland rodent.

Two Uinta ground squirrels standing at attention is a grassy field.

Uinta Ground Squirrel

Very active rodents that dig burrows in grassy areas.

A yellow-bellied marmot seen amongst brush and snow.

Yellow-bellied Marmot

Rodents that hibernate for eight months and are seen climbing around rocks.

 

Hares, Rabbits, & Pika (Order Lagomorpha)

These mammals are similar to rodents, except that they only eat plants and have four incisors in their upper jaws.

 
Pika carrying vegetation in its mouth.

Pika

An indicator species for detecting ecological effects of climate change.

Brown-colored snowshoe hare sitting in a patch of grass and rocks.

Snowshoe Hare

Common hare found in the park.

A white-tailed jackrabbit sitting amongst grass.

White-tailed Jackrabbit

Their coats change color with the seasons.

 

Bats (Order Chiroptera)

The only mammals that can fly, there are 13 species that call the park home.

 
A bat rests on some wooden posts.

Bats

Bats are the only mammals capable of sustained, flapping flight. Yellowstone has 13 species of bats in the park.

 

Resources

Curlee, A.P. et al., eds. 2000. Greater Yellowstone predators: ecology and conservation in a changing landscape. Proceedings of the Third Biennial Conference on the Greater Yellowstone Ecosystem. Jackson, WY: Northern Rockies Conservation Coop.

Feldhamer, G.A., B.C. Thompson, and J.A. Chapman, eds. 2003. Wild mammals of North America: Biology, management, and conservation. Baltimore: Johns Hopkins University Press.

Garrott, R. et al., editors. 2009. The ecology of large mammals in Central Yellowstone. San Diego: Academic Press.

Ruth, T. et al. 2003. Large carnivore response to recreational big-game hunting along the Yellowstone National Park and Absaroka-Beartooth Wilderness boundary. Wildlife Society Bulletin. 31(4):1–12.

Schullery, P. and L. Whittlesey. 1999. Early wildlife history of the Greater Yellowstone Ecosystem. Report, available in Yellowstone Heritage and Research Center Library.

Streubel, D. 2002. Small mammals of the Yellowstone Ecosystem. Juneau, Alaska: Windy Ridge Publishing.

White, P. J., Robert A. Garrott, and Glenn E. Plumb. 2013. Yellowstone's wildlife in transition. Cambridge, Massachusetts: Harvard University Press.

Last updated: October 23, 2017

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P.O. Box 168
Yellowstone National Park, WY 82190-0168

Phone:

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