Greater scaup Greater scaup 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. It spends the summer months breeding in Alaska, northern Canada, Siberia, and the northernmost reaches of Europe. During the winter, it migrates south to the coasts of North America, Europe, and Japan. Drake greater scaup are larger and have more rounded heads than the females; they have a bright blue bill and yellow eyes. Their heads are dark, with a green gloss; the breast is black, the belly white and the
Lesser scaup scientific name is derived from Ancient Greek "aithuia" an unidentified seabird mentioned by authors including Hesychius and Aristotle, and Latin, "affinis" "related to", from its resemblance to the greater scaup. Adults are long, on average. The species can weigh ; males weigh on average and weigh noticeably less, at on average. Wing lengths (not wingspans) are about in males and in females; the tarsus is about long, and the bill . The wingspan is . The adult males (drakes) in alternate plumage have a black, iridescent head and a small tuft at the hindcrown, a black breast, a whitish-grey back