It breeds on the Atlantic coast of North America, the Caribbean, and northern South America. Northernmost populations migrate farther south in winter, and this species occurs as a rare vagrant to western Europe. The laughing gull’s English name is derived from its raucous “kee-agh” call, which sounds like a high-pitched laugh “ha… ha… ha...”.
Laughing gulls breed in coastal marshes and ponds in large colonies. The large nest, made largely from grasses, is constructed on the ground. The three or four greenish eggs are incubated for about three weeks.
Belcher’s gull grows to a length of about 49 centimetres (19 in). The sexes are similar in appearance and in the breeding season, the adult has a white head and very pale grey neck and underparts. The mantle and back are greyish-black and the tail is white with a broad black subterminal band and a white trailing edge. The wing coverts and primaries are black and the secondaries dark grey with white tips. The eye is black, the bill yellow with a distinctive red and black tip, and the legs and feet yellow. Outside the breeding season the head is dark brown with a white ring surrounding the eye. The juvenile is mottled brown and white and attains the adult plumage during its third year. Belcher’s gull can be confused with the slightly larger kelp gull (Larus dominicanus) but that species has a small white tip on its otherwise black wing and lacks the Belcher’s gull’s black band on its tail.