Species: Chroicocephalus ridibundus

BREEDING: Iceland, Faroe Islands, Eurasia, southeastern Canada, northeastern U.S. European population expanded northward since the mid-1800s, probably due to amelioration of climate, increase in food supply resulting from human activities, and reduced persecution (Nikula 1993). Increasing numbers occurred in the 1900s in southeastern Canada and the northeastern U.S., where nesting has occurred in several areas (Labrador to Maine and Massachusetts) beginning in the 1970s; U.S. nestings have been unsuccessful and population expansion does not seem to be on-going (Nikula 1993). See also Brown and Nettleship (1984). NON-BREEDING: in North America along Atlantic coast from Labrador, Newfoundland, New Brunswick, and Nova Scotia south to New York (Long Island), rarely farther south and west, and in Old World. In North America, the largest numbers occur in the St. John's/Conception Bay area, Newfoundland, where a peak of a couple hundred occurs in November, and in Nova Scotia around the Sydney/Glace Bay area and around Halifax (Nikula 1993). Casual in Hawaii, Puerto Rico, and along Pacific coast of North America. Regular in spring in Aleutian and Pribilof Islands.