Below is a list of mammals (excluding species that live in the ocean) that have been seen in Olympic National Park. Some of the species below, like river otters and beaver, may spend much of their life in water but den outside of the water.
A=Abundant; C=Common; CL=Common locally; U=Uncommon; UL=Uncommon locally; R=Rare; **Endemic Mammals
Information obtained from the National Park Service website.