Larus ridibundus
Diet
Insects, fish, seeds, worms, scraps, carrion and invertebrates from ploughed fields
Habitat
Breeds in reed beds, marshes and lake islands; towns, coasts and farmland outside the breeding season
Range
Breeds across Europe and northern Asia from Iceland and Ireland to Japan and eastern China; migrates to northern Africa and southern Asia
Size
34-39cm
Wingspan
100-110cm
Weight
166-400g
The black-headed gull is a small gull, 34 to 39cm long with a wingspan of 100 to 110cm. Summer adults have a chocolate-brown head, white neck and underparts, pale grey wings and a red bill and legs; in winter the head turns white with two dark spots behind the eye. Young birds are mottled brown and take about two years to reach adult plumage (Wikipedia, general species account).
It breeds in colonies of a few pairs to several thousand on reed beds, marshes and lake islands, and is noisy, gregarious and omnivorous. Birds from colder regions migrate south, reaching northern Africa and southern Asia. The source does not name Nepal. Adults remove eggshells from the nest after hatching, which may reduce predation (Wikipedia, general species account).