As the summer fades into fall, thousands of migratory seabirds are using the 500 miles of Pacific Coast rocky islands, sandy beaches, estuaries, and mudflats in their flight south for the winter.
Migrating seabirds alike utilize these coastal areas to rest and forage on their incredible journeys between breeding and nonbreeding habitats extending from Northern Alaska into the Southern hemisphere.
Birds that migrate in the spring and fall along this extensive Pacific Flyway corridor keep close to the Pacific Coastal habitats, but migratory seabirds utilizing the same migration route are in a class of their own. Seabirds spend the majority of their lives in the water and have adapted to thrive in the extreme cold and wet environment.
Characteristics of seabirds include waterproof feathers, webbed feet, specialized eye glands to remove excess salt from their bodies, and other adaptations that enable life at sea.
Bird watching enthusiasts may be able to spot the below-listed species during their fall migrations along our diverse coast:
Sooty shearwaters (Ardenna grisea): This open-ocean dwelling migratory seabird prefers to forage by plunging beak first from a few feet above the water’s surface and utilizing strong silvery wings to swim underwater after prey or floating atop the water and using its quick beak to capture marine invertebrates. While visiting the Pacific Northwest the shearwater’s diet consists of primarily small fish, but can include squid, shrimp and jellyfish. These incredible birds create burrow and crevice nests in Australia, New Zealand, and Southern South America from September to May then travel to northern feeding grounds for our Northwest spring and summer. Mating begins at five years old and mating pairs work together to incubate a single egg for seven to eight weeks before it hatches then take turns feeding the hatchling for another fourteen weeks.
Brown pelicans (Pelecanus occidentalis): It is hard to miss the 8-pound brown pelican in flight as they extend their six foot wingspans as they migrate from British Columbia to South America. Utilizing keen eyesight and specially adapted air pouches beneath their skin, Brown pelicans can spot small fish and quickly plunge from over 60 feet into the ocean to fill 3-gallon throat pouches with water and prey. Needing up to four pounds of fish per day, Brown pelicans rely on smaller fish such as smelt and sardines in the Pacific Northwest. Breeding season in southern climates entails both parents of the mating pair helping to incubate the two-four clutch of eggs for approximately 28 days by covering the eggs with their webbed feet. Adults continue to feed growing pelicans for up to one year. According to the United States Fish and Wildlife Service, the brown pelican is a long lived bird and have been recorded to reach up to 31 years!
Caspian terns (Hydroprogne caspia): In North America, the Caspian tern is common along both coasts and found on both fresh and salt water. Western coolonies of terns prefer protected waters like bays, rivers, or lakes from Mexico to Alaska and have established the largest colony in North America within the lower Columbia River Estuary. For the last two decades 12,000- 20,000 Caspian terns have taken season residence on East Sand Island in the Columbia River which represents 50% to 65% of the Caspian tern breeding populations within the Pacific Flyway corridor. These birds are large as a gull, easily identifiable by their black-capped head and large orange bill and are common in bays and estuaries along the coast during spring and fall migrations. Smaller numbers of Caspian terns have even been found inland waters during migration including the mid-Columbia River, Willamette River and Snake Rivers. When feeding on small fish such as shiner perch, birds fly over the water, hover and plunge to catch prey at the waters surface, but have been known to steal fish or eggs from other birds for food. Once they reach reproductive maturity at five years, mating pairs incubate one-to-three pale brown/black spotted eggs for approximately 22 days. Young terns stay with parents up to eight months and as a species are able to live past 20 years.