Adult Plumage:
Summer Plumage: The head, from the forehead to the nape and crest, is velvety black. The upper back is light ash-gray. The first primary flight feather is gray-brown with a long white stripe on the inner vane. The other primary flight feathers are gray, but the inner vanes tend towards brown, and the white stripes diminish in size. The rest of the plumage is white.
Winter Plumage: The black coloration on the head disappears, or only a few small streaks remain on the crown and around the eyes. The eyes are brown. The beak and legs are black tinged with red. In winter, the legs are entirely black.
Measurements:
- Wing: 28 – 73 mm
- Tail: 121 – 18 mm
- Tarsus: 33 – 37 mm
- Beak: 35 – 41 mm
Distribution:
This species of tern is distributed in Europe, North Africa, Asia to Malaysia, Sumba Island, and Australia. In Vietnam, this species has only been observed in Ba Ria province.