Redhead

The redhead (Aythya americana) is a medium-sized diving duck. Its scientific name is derived from Greek aithuia, an unidentified seabird mentioned by authors including Hesychius and Aristotle, and Latin americana, of America. The redhead is 40–56 cm (16–22 in) long with an 74–84 cm (29–33 in) wingspan; weights range from 1,030–1,080 g (36–38 oz), with males weighing an average of 1,080 g (38 oz) and females an average of 1,030 g (36 oz). It belongs to the genus Aythya, together with 11 other described species. The redhead and the common pochard form a sister group, which together are sister to the canvasback. This waterfowl is easily distinguished from most other ducks by the male's copper-colored head and pale blue bill during the breeding season; from its close relative, canvasback, it is distinguished by the more rounded head, shorter bill, and (in the males) yellow, not red, eyes. The Eurasian common pochard is even more similar, but very rarely overlaps in range; it also differs in having a red eye, and a more acute, less rounded head shape.

Excerpt from the Wikipedia article Redhead (bird), by its authors, under the CC BY-SA 4.0 licence.