Size: L: 50 cm. Wt: 750-1200g. Males and females similar.
Breeding Adult: crown and nape black, with slight crest; cheeks white; neck chestnut; breast light chestnut; belly and flanks whitish; back black; bill long, stout, yellowish; eyes black
Winter Adult: crown, nape, back of neck, and back dusky or blackish; slight crest on head; white "chinstrap" extending upward behind ear; front of neck, and flanks greyish; bill long, stout, yellowish; eyes black
Immatures: may be similar to winter adult, but with rounder head (1st winter), or may have black and white head stripes, with faint red on neck (juvenile).
Chick: precocial and downy; white brow stripes; black crown; pale buff neck stripes; back and sides of body unstriped; bare scarlet patches on lores; bare patch on crown.