The Beaver is the largest rodent in North American, with an adult weight of up to 70 pounds. It builds dams of sticks and mud to slow rivers. It has prominent yellowish front teeth which it uses for eating bark and twigs, as well as for dam building. Extra large lungs allow the animal to stay under water fifteen minutes at a time. It's tail is broad and flat, unlike the smaller Muskrat which has a long, thin scaly tail.
Muskrats eat aquatic vegetation and can stay under water for up to five minutes.
Nuttall's Cottontail are commonly found around the visitor's center. They may spend their entire lives on a single acre. The White-tailed Jackrabbit has very long ears to detect coyotes and other predators in the grasses. The colors of the Snowshoe Hare vary with the seasons, changing from brown in summer to white in winter. This involves emitting 50 - 60 high pitched calls per second and locating prey by the echos of these calls.