The lesser scaup (Aythya affinis) odd name may derive from two sources – the bird's preference for feeding on scalp, the Scottish word for clams, oysters, and mussels; or the female's discordant scaup call. It is a small North American diving duck with a resemblance to the tufted duck that migrates south as far as Central America in winter. The Lesser Scaup was first described in 1838 by Thomas Campbell Eyton, an English naturalist. It is one of the most abundant and widespread of the diving ducks in North America.