Description:
The species is 60 cm in length and is a large, slender gull, possessing a robust bill. Adults have gray upperparts contrasting with a black head and wings. Small white spots are present on the primary flight feathers. The yellow bill has a red spot (in the largest gulls), and the legs are pink. The eyes are yellow, round, and bright, with a yellowish-orange eye-ring.
In winter, the head and neck display prominent pale brown streaks. First-winter birds have a brown plumage mottled, contrasting with the primary feathers and the pale brownish-black tail band (contrasting with the pale white tail base and flanks). The eyes are dark. The bill is entirely black and sometimes has a pale pink base at other times. As the birds age, they become grayer and paler.
Distribution:
Possible presence in Northeast Vietnam (coastal areas of the Red River Delta), though not definitively confirmed. This species typically inhabits coastal regions.
Status:
Migratory species, rarely encountered.