Lesser scaup Lesser scaup The lesser scaup ("Aythya affinis") is a small North American diving duck that migrates south as far as Central America in winter. It is colloquially known as the little bluebill or broadbill because of its distinctive blue bill. The origin of the name scaup may stem from the bird's preference for feeding on scalp—the Scottish word for clams, oysters, and mussels; however, some credit it to the female's discordant scaup call as the name's source. It is apparently a very close relative of the Holarctic greater scaup or "bluebill" ("A. marila"), with which it forms a superspecies. The
Greater scaup wing shows a white stripe. The females are mostly brown, again with white on the wing. They have dull blue bills and white on the face. Greater scaup nest near water, typically on islands in northern lakes or on floating mats of vegetation. They begin breeding at age two, but start building nests in the first year. The drakes have a complex courtship, which takes place on the return migration to the summer breeding grounds and concludes with the formation of monogamous pairs. Females lay a clutch of six to nine olive-buff-colored eggs. The eggs hatch in 24 to 28