Dominant color of male Smew in breeding plumage is white. From bill-base to eye the broad greenish-tinged black strip passes; same color strip cross passes the nape, behind the extended feathers formed crest. Two narrow black strips are on each breast-flank. Back, outer shoulders, greater wing coverts anf flight feathers are black. Uppertail is dark-grey with pale tips of feathers. Flanks of body are with narrow grey wave strips. Tail is grey. Female has rusty-brown crown and rear-neck, white throat and fore-neck, almost black lores. There is small crest on nape. All upperparts are grey, darker on mantle, shoulders are browner. Craw, flanks and belly are white with not clear grey-brownish mottles; undertail is clear white. Wings as on male. Juveniles are similar on female, but all color are dim and underparts are almost dark-grey. Male in summer is undifferent from female. Bill is leaden, legs are grayish with darker web. Eyes are bluish-white in male and brownish in female and juvenile. Sizes: wing 175-205 mm, tail 67-80 mm, tarsus 28-34 mm, bill 25-30 mm. Weight: 450 - 750 gr.
"Птицы Казахстана" том 1. АН КазССР. Алма-Ата, 1960.
