Stejneger's Scoter is a diving duck with a prominent swelling at the base of the bill. It moves from northern breeding areas to Pacific coasts for winter.
In breeding plumage, the male has red and yellow-orange on the bill and a large black swelling at its base. The female is dark brown with pale areas on the sides of the head.
In summer it eats insects, crustaceans, and freshwater molluscs. In winter, marine bivalves and snails are important foods; it dives to take prey from the water and bottom.
An extinction-risk assessment has not been added yet.