The Pacific Northwest (PNW) is a distinct geographic region in western North America, encompassing the U.S. states of Washington, Oregon, Idaho, and the Canadian province of British Columbia. Its diverse topography ranges from Pacific coastlines to the towering Cascade Range and Olympic Mountains, and stretches eastward to the Columbia Plateau. The region’s oceanic climate, marked by cool to mild temperatures and frequent rainfall, fosters lush temperate rainforests and a network of river systems, including the Columbia and Snake Rivers. These varied landscapes and climatic conditions contribute to a rich biodiversity, creating a multitude of habitats for diverse animal life.
Mammals of the Pacific Northwest
The Pacific Northwest is home to a wide array of both terrestrial and marine mammals. Among the larger land mammals are the Roosevelt elk (Cervus canadensis roosevelti), recognized as the largest subspecies of North American elk. These herbivores typically inhabit coastal forests and mountainous areas from northern California through British Columbia and into Alaska. Roosevelt elk graze on various plants, including grasses, flowers, and ferns, and browse on shrubs and tree branches, often migrating to higher elevations in summer and lower valleys in winter.
Black-tailed deer (Odocoileus hemionus columbianus), a subspecies of mule deer, are frequently encountered throughout the region, thriving in coniferous forests and brushy environments. These deer are most active during dawn and dusk, foraging on a diet of shrubs, leaves, grasses, and berries. Cougars and bobcats also roam the forests, while smaller mammals such as Douglas squirrels, martens, and various bat species are present. The coastal waters of the Pacific Northwest support a robust population of marine mammals.
Orcas, known for their complex social structures, patrol these waters, preying on salmon. Various seal species, including harbor seals and elephant seals, along with sea lions and porpoises, are commonly observed near the coast and in inland waterways. Several whale species also frequent the offshore areas.
Avian Diversity
The Pacific Northwest provides habitat for a broad spectrum of bird species. Raptors are well-represented, with species such as bald eagles, ospreys, and various owls. Hawks, including the Sharp-shinned Hawk and Red-tailed Hawk, along with falcons like the Peregrine Falcon and American Kestrel, are also present.
Waterfowl are abundant, with numerous species of ducks, geese, and swans utilizing the region’s lakes, rivers, and coastal wetlands. Common ducks include Mallards, Northern Shovelers, American Wigeons, and Green-winged Teals, while larger birds like Canada Geese and Trumpeter Swans are regular inhabitants. The Pacific Northwest is also a haven for songbirds, featuring finches like House Finches and American Goldfinches, various wren species, and chickadees such as the Black-capped and Chestnut-backed Chickadee. Sparrows, including the Song Sparrow and White-crowned Sparrow, are also found here.
Coastal birds thrive along the extensive shoreline, with species like gulls, Tufted Puffins, and various cormorants inhabiting rocky islands and cliffs. The Common Murre and Black Oystercatcher are also residents of the coastal areas. The Pacific Northwest plays a significant role in the Pacific Flyway, a major migratory route. Millions of birds use this flyway annually, with the region’s wetlands and estuaries serving as important stopover and refueling points during their long journeys.
Aquatic and Amphibious Life
The waters and wetlands of the Pacific Northwest host a diverse array of aquatic and amphibious creatures. Five distinct species of Pacific salmon—Chinook, Sockeye, Coho, Chum, and Pink—inhabit the region’s rivers and marine environments. These anadromous fish begin their lives in freshwater, migrate to the ocean to mature, and then return to their natal streams to spawn before dying. Salmon are a foundational species, providing substantial nutrient input into both aquatic and terrestrial ecosystems upon their death, enriching the water and surrounding land, supporting a wide range of wildlife.
Beyond salmon, the region’s freshwater and marine systems support many other fish species. Amphibians are also well-represented, thriving in the moist conditions characteristic of the Pacific Northwest. Various salamander species, such as the Pacific Giant Salamander, Northwestern Salamander, and the Columbia Torrent Salamander, are found in moist forest floors, wetlands, and cold, clean streams. Newts, including the Rough-skinned Newt, also inhabit these damp environments.
Frog species, such as the Pacific Tree Frog and Oregon Spotted Frog, are common residents. While less diverse than other groups due to the cooler, wetter climate, reptiles are present in specific microclimates within the Pacific Northwest. Garter snakes are among the more common reptile species, along with some lizard and turtle species.