Olympic National Park on the Olympic Peninsula of Washington State encompasses a rare trifecta of distinct ecosystems: glaciated peaks, temperate rainforests, and a rugged Pacific coastline. This unique geography and isolation have fostered biodiversity. The park is home to 62 terrestrial and 29 marine mammal species, and nearly 300 bird species. These varied environments support fauna ranging from endemic alpine species found nowhere else to charismatic megafauna in the valleys and cold Pacific waters.
Iconic High-Elevation and Endemic Species
The subalpine and alpine zones of the Olympic Mountains host specialized and unique wildlife. The Olympic marmot (\(Marmota\) \(olympus\)) is a large, ground-dwelling rodent endemic to the Olympic Peninsula and recognized as Washington’s official endemic mammal. These social creatures, about the size of a domestic cat, live in colonies on high meadows and talus slopes, spending seven to eight months of the year in deep hibernation. Marmots reach their heaviest weight of up to 18 pounds before dormancy, relying entirely on stored body fat to survive.
The marmot’s piercing whistle is a common alarm call against predators like the coyote, which has become a primary threat. Another high-elevation species is the mountain goat (\(Oreamnos\) \(americanus\)), which is non-native, having been introduced in the 1920s. Their population grew significantly, but their trampling, grazing, and seeking of salts damaged the fragile alpine vegetation and soils, which support rare endemic plants.
The National Park Service implemented a management plan to remove the non-native goats, translocating hundreds of animals to the Cascade Mountains where they are native. This program, largely completed in 2022, aims for the complete removal of the species from the Olympic Peninsula to protect the sensitive alpine ecosystem. The isolated mountain environment has also led to the evolution of other endemic species, such as the Olympic snow mole and the Olympic chipmunk, found only within the park’s boundaries.
Temperate Rainforest and Forest Mammals
The lower-elevation old-growth forests and temperate rainforest valleys, such as the Hoh and Quinault, host a different suite of large mammals. The Roosevelt elk (\(Cervus\) \(canadensis\) \(roosevelti\)) is an icon of this ecosystem, representing the largest subspecies of elk in North America by body mass. Male bulls can weigh up to 1,100 pounds, and their protection was a driving force behind the establishment of the Mount Olympus National Monument in 1909.
Elk herds browse on ferns, shrubs, and meadow grasses year-round. Non-migratory herds in the Hoh area consist of small groups of females and their calves, and bulls bugle during the fall mating season. The American black bear (\(Ursus\) \(americanus\)) shares the forest floor and ranges into subalpine areas; it is the only bear species present in the park.
These omnivores have a highly varied diet, feeding on tree bark and insects in the spring before switching to berries in the late summer and fall, and fishing for spawning salmon. They play a role in the forest’s health by dispersing seeds and recycling nutrients when turning over logs to access insects. Another forest dweller is the Pacific fisher (\(Pekania\) \(pennanti\)), a member of the weasel family that was extirpated from the region due to over-trapping and habitat loss.
A reintroduction project began in 2008 to reestablish a self-sustaining population of fishers in the park’s forests, where they prey on small mammals like snowshoe hares. The park also supports a healthy population of black-tailed deer, a subspecies of mule deer commonly sighted across forest and meadow areas. These animals, along with the elusive cougar, inhabit the park’s dense interior.
Coastal and Marine Inhabitants
Olympic National Park’s 73 miles of protected coastline hosts a distinct group of wildlife. The cold, nutrient-rich Pacific waters are part of the Olympic Coast National Marine Sanctuary, home to 29 species of marine mammals. Gray whales are common during their annual migration from March through May as they travel north to their summer feeding grounds.
The sea otter was hunted to extinction off the Washington coast by the early 1900s but has recovered following reintroduction efforts. They are the only marine mammals known to use tools to open shellfish and can be spotted in the kelp forests offshore. Harbor seals are year-round residents, frequently seen resting or “hauling out” on rocky outcrops.
The intertidal zones exposed at low tide reveal invertebrates living in tide pools. These areas are teeming with life, including colorful sea stars, anemones, and crabs. Organisms here are specially adapted to cling to the rocks and survive the constant ebb and flow of the ocean tides.
Avian and Smaller Wildlife Diversity
The park’s varied habitats support a wide array of avian life, with approximately 300 species of birds recorded across the mountains, forests, and coast. Raptors like the bald eagle are often seen along the coast, hunting for fish and waterfowl, with large nests visible in the tallest trees. In the old-growth forests, the federally threatened northern spotted owl relies on the dense, mature canopy for nesting and hunting flying squirrels and wood rats.
The spotted owl population faces pressure from the non-native barred owl, a more aggressive competitor that has expanded its range westward. The park’s wet environment supports 13 species of amphibians, including frogs, toads, and salamanders. Among these is the Olympic torrent salamander (\(Rhyacotriton\) \(olympicus\)), found only on the Olympic Peninsula, which lives in cold, clear mountain streams.
This smaller wildlife includes unique invertebrates, such as the Olympic grasshopper and the Keeled jumping slug. These species, like many of the park’s inhabitants, demonstrate the biological distinctiveness resulting from the peninsula’s geographic isolation.