The mammals of the refuge are typical of those found in the Greater Yellowstone area and the northern Rocky Mountains. The mountain forests provide an ideal habitat for mammals for shelter and food. The large mammals are not easy to see because many are cautious of humans and generally feed in early morning and late evenings or night.  The refuge acts as a corridor for some mammals (like the Grizzly Bear) for moving between Yellowstone and other areas of Idaho and Montana. Read a list of mammals found on the refuge or Download  a list to print.

  • Moose

    Moose Head

    The moose is the largest member of the deer family. It is usually found in the  refuge feeding among the numerous willows near creeks, wetlands, or along the edge of the forest. A mature male moose is referred to as a bull; a mature female moose is a cow; and an immature moose of either sex is a calf.

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  • Elk

    Male Elk

    The elk is one of the largest members of the deer family.  Elk range in forest and forest-edge habitat, feeding on grasses, plants, leaves, and even bark. Sometimes they will be found feeding in the meadows east of Upper Red Rock Lake, among the willows. They shed their antlers once a year after mating in the fall.

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  • Pronghorn

    Antelope and Baby

    Pronghorn are one of the most visible larger mammals on the refuge. They are grazing ungulates and are generally considered the fastest running mammal on the North American Continent and the second fastest in the world (the cheetah is the fastest). They can run up to 55 mph for short distances and sustain 35 mph for a long time. They have very large eyes, with a 320 degree field of vision.

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  • Deer

    Deer with Antlers

    Both white-tailed and mule ear deer are found along the forest edges at the refuge. They are shy creatures and like to munch on vegetation where there is nearby shelter from the wolf, coyote, grizzly bear and human predators.

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  • River Otters

    River Otters thumbnail

    The North American river otter lives in the shallow ponds and creeks at the refuge, dining on the  many fish and invertebrates living there. River otters are mostly nocturnal but can be seen during the day at the refuge. On land, the river otter can walk, run, bound, or slide.

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  • Bears

    Grizzly Bear thumbnail

    Grizzly and black bears are visitors from the forests around the refuge but aren't seen much by visitors. Although the diets of these bears vary extensively based on seasonal and regional changes, plants make up a large portion of their diet, with some estimates as high as 80–90%. Both bears are known to prey on other smaller mammals when conditions are right. They generally shun human presence unless surprised or protecting a food source.

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  • Other Mammals

    Fox small

    There are many other mammals on the refuge, most notably, wolf, coyote, fox, badger, skunk, cougar, lynx, bobcat, porcupine, wolverines, mink, marten, weasels, pika, and many rodents including beavers, marmots, squirrels, porcupine, chipmunks, mice, and more. They all play an important role in keeping the ecosystem in balance.

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