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.

Burrowing predator of small rodents.

a grizzly bear walking through sagebrush

Two species of bears inhabit Yellowstone: grizzly and black bears.

A bobcat walking through a snowy field of brush.

One of the elusive cats of Yellowstone.

Lynx are one of three cat species found in Yellowstone.

Largest of the cat species in Yellowstone.

A canine with large pointy ears looks at the camera

Coyotes are abundant throughout the park.

Gray wolves, restored in 1995, freely roam the park.

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

Long-tailed weasels change color based on the season.

A reddish-brown marten up in a conifer tree.

Member of the weasel family that lives in woodlands.

Smallest of the three canid species found in the park.

Four river otters resting on a snowy river bank.

The most aquatic of the weasels in the park.

A short-tailed weasel looks back over its shoulder.

Small weasels also known as ermine.

A mid-size carnivore in the weasel family.

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

Yellowstone bison exhibit behavior like their ancient ancestors.

Most bighorn sheep in Yellowstone are migratory.

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

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 are the largest members of the deer family in Yellowstone.

Two mountain goats standing upon a rock pinnacle.

Mountain goats are considered non-native species.

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

A pronghorn looking directly at the camera.

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.

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.