Black-headed Gull (Larus ridibundus)
The black-headed gull’s common name is somewhat misleading, in that its head is not black, but dark brown. Its French name, ‘mouette rieuse’, which means ‘laughing gull’, refers to its laughing call.
The black-headed gull is relatively small, measuring 35-38 cm in length, with a dark brown head and narrow white ring around its eye. Its body, neck, rump and tail are white, and its wings and back are pale grey. The ends of its wings are white, with black-tipped primary feathers. This gull can be differentiated from similar species by its slightly larger size- its dark red bill, and the dark grey-black areas on the underside of its wings. In the winter, its head becomes white, but, unlike many other gulls, its bill remains reddish. Juvenile gulls are mostly white, with a mixture of brown and grey areas on their back and wings. Their dull yellow, black-tipped bill distinguishes them from juveniles of other gull species.
The black-headed gull has historically been confined to Iceland and Eurasia, but its range has been expanding recently to include the Atlantic coast of North America. It currently nests in a few areas in the Canadian Maritimes.
The black-headed gull inhabits coastal marshes and freshwater areas farther inland, where it often nests within colonies of other gulls, particularly the laughing gull. The male gull selects a nesting site on the ground, and begins to build a nest of dried grass. Both birds help to finish the task, and continue adding to the nest during incubation, often using materials stolen from the nests of neighbours! The female lays 2-3 greenish to brownish, brown-spotted eggs, which are incubated for 23-26 days by both parents.
Black-headed gulls are omnivorous, consuming aquatic and terrestrial invertebrates, vegetation and garbage. Food is picked off the ground or from the surface of the water, and sometimes other birds are chased and their food is stolen.