Adult Plumage:
Summer Plumage:
- Upperparts: Pale black, with each feather having a broad rufous border on either side and a pale white tip.
- Lower Back, Rump, and Uppertail Coverts: Pale black.
- Flanks: White.
- Central Tail Feathers: Pale black.
- Lateral Tail Feathers: Brown.
- Primary Feathers: Pale black, with the base of the first primary being white.
- Tertiary Feathers: Brown with white edges.
- Greater Coverts: Brown with white edges, forming a narrow white band across the wing.
- Supercilium: Pale white with black streaks.
- Chin and Throat: Pale white.
- Sides of Head, Sides of Breast and Upper Breast: Pale grayish-rufous with pale black speckles.
- Axillaries: White.
Winter Plumage:
- Upperparts: Pale blackish-brown, with each feather edged with gray.
- Sides of Head, Foreneck, and Breast: Pale gray with dark brown streaks along the feather shafts.
- Eyes: Brown.
- Bill: Yellowish-brown or pale black.
- Legs: Pale yellowish-green or pale brown.
Measurements:
- Wing: 85 – 96 mm
- Tail: 40 – 44 mm
- Tarsus: 20 – 25 mm
- Bill: 17 – 19 mm
- Middle Toe (including claw): 22 – 25 mm
Distribution:
This species nests in Siberia, Japan, and Alaska. It migrates south for the winter to China, Indochina, Myanmar, India, and Malaysia. In Vietnam, this species is present along the coast of Thừa Thiên Province during the winter.