The American Scoter is a sea duck that breeds in boreal North America and moves to coastal waters in winter.
Males are black with a bright knob at the base of the bill. Females are brown with pale cheek patches.
Researchers used satellite tracks from 70 Black Scoters tagged between 1999 and 2019 to estimate breeding locations and arrival times. Pacific-wintering Black Scoters were mainly estimated to breed in Alaska, while Atlantic-wintering birds were concentrated in eastern Canada. Estimated mean arrival was 28 May for Pacific birds and 6 June for Atlantic birds.
The principal North American waterfowl breeding survey areas covered about half of the estimated Black Scoter breeding locations. Other estimated areas included western Northwest Territories, Nunavut, northern Manitoba and Québec, and Labrador. The authors note that surveys covering the full breeding distribution are needed to assess how well population estimates represent the species.
An extinction-risk assessment has not been added yet.
Satellite tracking placed about half of estimated Black Scoter breeding locations outside the main North American survey areas. Including northern breeding sites in surveys would make distribution records and population estimates cover more of the species’ range.