Size: L: 35cm. Wt: 300-400g. Sexually dimorphic in colour, but only minimally in size. This species not seasonally dimorphic.
Male: upperparts grey-brown, with green speculum on wing, and buffy rump; head chestnut, with large, dark green ear patch; breast whitish or buffy, with even, dark speckling; sides grey; tail dark; bill blackish
Female: upperparts (including rump) mottled brown, with green speculum on wing; head mottled brown, with grayish cheeks and dark eye-line; breast and sides mottled brown; underparts whitish; tail dark; bill blackish
Duckling: upperparts dark greenish-yellow; underparts yellow; double eye-stripe; bill, legs and feet blackish