
Aythya marila
John James Audubon, Birds of America (1827-1838). Public domain.
Showing primary migration corridor(s) for this species
The greater scaup (Aythya marila), just scaup in Europe or, colloquially, "bluebill" in North America, is a mid-sized diving duck, larger than the closely related lesser scaup and tufted duck. It spends the summer months breeding in Iceland, east across Scandinavia, northern Russia and Siberia, Alaska, and northern Canada. During the winter, it migrates south to the coasts of Europe, eastern Asia, and North America. Male greater scaup average slightly larger than the females but with much overlap; they have a light blue-grey bill and yellow eyes. Their heads are dark, with a green to purple (depending on light angle) gloss; the breast is black, the belly white, the upperparts pale grey, and the wing shows a strong white stripe. The females are mostly brown, again with white on the wing.
Source: Wikipedia
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