Description
Adult Male:
Summer Plumage: Generally, the plumage is a mix of rufous, white, and black. The head and upper neck are black with a steel-like sheen. The lower neck features a wide white collar. A dark rufous-brown band extends from the upper back, curving over the front of both shoulders down to the chest. The shoulders are black. The remaining back, rump, and upper tail coverts are white. A black band begins in the middle of the chest and extends down to the abdomen. The flanks are white. The under tail coverts are rufous. The wing coverts are white. The primary feathers are dark brown. The speculum (wing patch) has a steel-like green sheen. The outer webs of the tertiary feathers are bright rufous. The tail feathers are white with black tips.
Winter Plumage: Similar to the female plumage; the caruncles (fleshy protuberances at the base of the bill) are undeveloped. The black band on the abdomen may sometimes be indistinct.
Female:
- Generally similar to the male plumage, but the coloration is duller, with less sheen, and the black areas are replaced with black-brown. The black-brown band on the abdomen has white spots.
Juvenile:
- The forehead and sides of the head are white. The crown and neck are brown. Faint rufous coloring is present on the sides of the chest. The posterior chest and abdomen are white. The eyes are brown. The bill is reddish-purple. The legs are pale pink.
Measurements
- Wing Length: Male: 300-160 mm, Female: 280-330 mm
- Tail Length: 108-125 mm
- Tarsus Length (leg): 50-58 mm
- Bill Length: Male: 52-60 mm, Female: 43-55 mm
- Weight: 1.00-1.65 kg
Distribution
The species is distributed from the Scandinavian Peninsula, the Mediterranean region to Iran, the Soviet Union, Mongolia, and Northern China. During winter, they migrate southwards.
In Vietnam, this species is occasionally found near the coast during winter, but it is very rare.