Bonaparte's Gull - Chroicocephalus philadelphia

Adult is a small gull with a white triangle in the outer part of the wing. The bill is blackish, the back is pale grey, the underparts white and the head is black during breeding season. There is a dark spot behind the eyes in winter. Juvenile has more brown on head, neck, and back, a dark bar across the wing, and a black tail tip. Immature is similar to nonbreeding adult, but with brownish black bar across the base of the wing, much black in the outer wing, and a black band across the tip of the tail. In first breeding plumage the black head is partly mottled with white.

A migrant species most often seen near to the coast.

Not a breeding species in Britain but may turn up at any time.

Infrequent migrant to Britain.

Rare migrant in Leicestershire and Rutland.