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|Non-breeding adult in Ohio|
The Ring-billed gull (Larus delawarensis) is a medium-sized gull.
Adults are 49 cm (19 in) length and with a 124 cm (49 in) wingspan. The head, neck and underparts are white; the relatively short bill is yellow with a dark ring; the back and wings are silver gray; and the legs are yellow. The eyes are yellow with red rims. This gull takes three years to reach its breeding plumage; its appearance changes with each fall moult.
Distribution and habitat
Their breeding habitat is near lakes, rivers, or the coast in Canada and the northern United States. They nest colonially on the ground, often on islands. This bird tends to be faithful to its nesting site, if not its mate, from year to year.
The ring-billed gull is a familiar sight in the shopping mall parking lots of the United States, where it can regularly be found congregating in large numbers. In some areas, it is displacing less aggressive birds such as the common tern.
These birds forage in flight or pick up objects while swimming, walking or wading. They also steal food from other birds and frequently scavenge. They are omnivorous; their diet may include insects, fish, grain, eggs, earthworms and rodents. These birds are opportunistic and have adapted well to taking food discarded or even left unattended by people. It is regarded as a pest by many beach-goers because of its willingness to steal unguarded food on highly crowded beaches. The gull's natural enemies are rats, foxes, dogs, cats, raccoons, coyotes, eagles, hawks, and owls.
In the late 19th century, this bird was hunted for its plumage. Its population has since rebounded and it is probably the most common gull in North America.
- BirdLife International (2012). "Larus delawarensis". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
- "Ring-billed Gull". Common Birds of New England. Retrieved 16 March 2014.
- Ray, C. Claiborne. "Why do Sea Gulls Like Parking Lots?". New York Times. Retrieved 16 March 2014.
- National Geographic, Field Guide to the Birds of North America, ISBN 0-7922-6877-6
- Seabirds, an Identification Guide by Peter Harrison, (1983) ISBN 0-7470-1410-8
- Handbook of the Birds of the World Vol 3, Josep del Hoyo editor, ISBN 84-87334-10-5
- National Audubon Society. The Sibley Guide to Birds, by David Allen Sibley, ISBN 0-679-45122-6
|Wikimedia Commons has media related to Ring-billed gull.|
|Wikispecies has information related to: Larus delawarensis|
- Ring-billed Gull Species Account – Cornell Lab of Ornithology
- Larus delawarensis on Avibase
- Ring-billed Gull - Larus delawarensis - USGS Patuxent Bird Identification InfoCenter
- Ring-billed Gull Field Guide Page on Flickr
- Ring-billed Gull at Université du Québec à Montréal (UQAM)'s Research and banding program
- Ring-billed Gull videos, photos, and sounds at the Internet Bird Collection
- Ring-billed Gull photo gallery at VIREO (Drexel University)
- Interactive range map of Larus delawarensis at IUCN Red List maps