The Larus canus is a widespread medium-sized gull found across the Northern Hemisphere. It is known as the Common Gull in Europe and Asia, and the Mew Gull in North America. The species includes four recognized subspecies, though the North American subspecies, L.c. brachyrhynchus, is sometimes considered a distinct species.
Physical Characteristics and Common Names
Adult Larus canus measures 40 to 46 centimeters (16 to 18 inches) in length, with a wingspan of 110 to 125 centimeters (43 to 49 inches). In breeding season, plumage features a pure white head, body, and tail, contrasted by a pale grey mantle and upperwings. The wingtips are black with prominent white spots on the outer primary feathers.
The bill of a breeding adult is greenish-yellow and lacks markings; legs and webbed feet are also greenish-yellow. Their eyes are dark with a reddish eye-ring. During the non-breeding season, the head and hindneck may show grey streaking, and the bill might develop a narrow, dark band near the tip. Juveniles exhibit a mottled grey-brown appearance with a dark grey bill and pinkish legs that later turn yellow.
Where They Live and Migrate
The Larus canus breeds in cool temperate regions across the Palearctic, from Iceland to Kamchatka. In North America, the Mew Gull subspecies (L.c. brachyrhynchus) breeds in northern Alaska and northwestern Canada, extending south into British Columbia and Saskatchewan. These gulls inhabit coastal areas, tidal estuaries, inland lakes, and marshy grasslands.
Many populations are migratory, moving south for the winter. European and Asian populations winter along the Mediterranean, Black, and Caspian Seas, and the coasts of China and Japan. North American populations disperse south along the Pacific coast to California. While primarily coastal in winter, they also frequent large inland lakes and agricultural areas.
What They Eat and How They Behave
Larus canus is an opportunistic omnivore. Their diet includes:
Fish
Marine invertebrates
Mollusks
Insects
Earthworms
Small mammals
They forage by dipping into water or waiting for prey while floating. They also scavenge human food waste in urban environments and follow agricultural equipment to catch disturbed invertebrates.
These gulls are social and breed in colonies near water or marshes. Nests are shallow scrapes lined with vegetation, built on the ground or in small trees. Females lay two to three olive-brown eggs with dark speckles, incubated by both parents for 24 to 26 days. Chicks fledge after 30 to 35 days, continuing to be fed by parents for several more weeks. The Common Gull’s call is a distinctive high-pitched “laughing” cry, with softer “mewing” sounds during the breeding season.
Conservation and Population Trends
The Larus canus is classified as a species of “Least Concern” by the IUCN Red List. The global population is estimated at one million pairs, with 80-90% residing in Europe. Despite this stable status, local populations can face pressures from habitat loss, pollution, and changes in food availability.
Climate change can influence gull populations by affecting food supply. Low-lying nests are susceptible to flooding, and increased storminess can reduce productivity. Monitoring populations and protecting important breeding and feeding habitats are ongoing conservation efforts.