In all plumages, this species can be recognized its mostly white plumage and its bold black and white wing pattern in flight. Alternate Male: White overall, with a black back, black wing tips, and black inner tail feathers. The bill is black. Alternate Female: White underparts. Back is dark ashy-gray with white streaking. Gray streaks on crown and nape, with a rufous wash on the shoulder and wings. Wing shows more dark on leading edge than male, but still has extensive white patch and black tips. Basic Adult: White overall, with highly variable mix of gray, black, and warm rusty-brown on back and scapulars. Head mostly white, with rusty brown smudge on auriculars and varying amount of rusty-brown on crown and nape. Underparts entirely white, except for partial collar of rusty-brown on sides of upper breast and some buffy rusty-brown wash on flanks. Wing pattern like Alternate. Bill is dull yellow.

Length: 16 (cm) Wingspan: 30 (cm)

Voice:

Song is a hoarse repeated warble. Flight calls include a sharp tew, a short buzz, soft rattle.

Habitat:

Nests in rocky cavities surrounded by tundra. In winter, found on beaches, short grasslands, agricultural stubble fields.

Behavior:

In winter, often found in large swirling flocks.

Feeding:

Forages on the ground for seeds, insects.