Skinner, M.P. 1927. The Predatory and Fur-bearing Animals of the Yellowstone National Park. Roosevelt Wild Life Bulletin, Vol. Mammals of Yellowstone National Park Yellowstone National Park is home to the largest concentrations of large and small mammals in the lower 48 states. Non-native mountain goats appear to be colonizing the park.
Numerous carnivores roam the area, including grizzly and black bears.
Black bears are common. The gray wolf was native to the Yellowstone area, but was eliminated in the 1930s. In 1995, it was restored to the ecosystem. Mountain lions, bobcats, coyotes, and red fox also live here. A wide variety of small mammals, from chipmunks to marmots to squirrels to weasels to voles and mice inhabit the park.