- Larus philadelphia
Identification
Distribution
Breeds in Alaska and east across Canada to James Bay with non-breeders present in summer on north-eastern coasts.
Winters from the Great Lakes southwards and on the Atlantic coast from New England south to the Caribbean. Leaves breeding grounds in late July with many gathering off Nova Scotia in late August-early September, return movement in April-May.
Fairly frequent vagrant to the Western Palearctic most often recorded in the British Isles but also in Iceland and Scandinavia, the Netherlands, Belgium and France, Germany, Hungary, Iberia, Morocco and the Azores. British records (c.115) mainly in the south-west but also east to Norfolk and north to Shetland. The records are spread throughout the year and include long-staying and returning individuals and both adults and immatures.
Taxonomy
There are no known subspecies. Some authorities place this species in genus Chroicocephalus.
Habitat
Breeds beside pools and swamps in tundra and taiga. Out of the breeding season found at freshwater and saline lakes, following the plough on farmland and by the sea. In coastal areas seen on sandy shores and mudflats, estuaries, harbours and on coastal lakes and lagoons.
