Adult male scoters of all species are black, but black scoters are the blackest; their shiny black plumage bears no white. The swollen bright orange-yellow knob on the otherwise black bill is smaller than that of other scoters.

Males are distinguished in flight by the flashing silver-gray of underwing flight feathers against black wing linings and the all-black body. Females' uniform soot upperparts and dark head cap are clearly delineated from paler cheeks; their bills are usually dark. Immatures resemble females, but most males acquire some black feathering the first fall.

This scoter can be uncommon to locally common along the coast fall through spring, usually on the ocean.

Hear the call of the black scoter

Photo by Aaron Maizlish, Flickr