The California gull is a medium-sized gull, smaller on average than the herring gull, but larger on average than the ring-billed gull. Although named after California, it can be found annually across most of western North America, from the Canadian prairie provinces in the northeast and south through western Mexico.
Region
Western North America
Typical Environment
Breeds on lakes, marshes, and islands across the northern Great Plains, Great Basin, and interior West, including the Canadian Prairies and the U.S. Intermountain West. In winter it is common along the Pacific coast from British Columbia through Baja California and into western Mexico, and persists at large inland waters such as the Salton Sea and the Great Salt Lake. It uses reservoirs, agricultural fields, landfills, and urban shorelines, showing a strong tolerance for human-altered habitats. Colonies are typically sited on low, sparsely vegetated islands or shorelines where predators are fewer.
Altitude Range
Sea level to 2500 m
Climate Zone
Temperate
Ease of Keeping
Beginner friendly: 1/5
Despite its name, the California gull breeds widely across interior western North America and winters along the Pacific coast and nearby inland waters. It is Utah’s state bird, celebrated for the 1848 'Miracle of the Gulls' when huge flocks consumed swarms of Mormon crickets threatening pioneer crops. Adults can be distinguished from similar ring-billed gulls by their darker iris and a bill marked with both red and black spots.
Feeding on brine flies, in San Diego
Temperament
social and opportunistic
Flight Pattern
strong flier with steady wingbeats and occasional soaring
Social Behavior
Highly colonial breeder, nesting in large, dense groups on islands or remote shorelines. Pairs are generally monogamous within a season, building ground nests from vegetation and debris. Outside the breeding season it forms sizeable flocks at roosts, feeding sites, and landfills, often mixing with other gull species.
Migratory Pattern
Seasonal migrant
Song Description
Vocalizations include loud, rasping keee-ar and kyow calls, with series of yelps and cackles during displays. Alarm calls are harsh and repeated in chorus at colonies. Chicks and mates use softer mews and squeals at close range.
Plumage
Adult shows clean white head and underparts with a medium-gray mantle and black wingtips that bear white 'mirrors'; in nonbreeding season the head is lightly streaked. Juveniles pass through mottled brown stages with increasingly gray upperparts over successive years.
Diet
An opportunistic omnivore that takes insects (notably grasshoppers and crickets), brine flies and their larvae, small fish, crustaceans, and marine invertebrates. It also scavenges carrion and human refuse and may steal eggs or chicks from other birds when opportunities arise. In agricultural areas it follows plows and concentrates where insect outbreaks occur, a behavior famed from historical accounts in Utah.
Preferred Environment
Forages along lake and reservoir shores, river mouths, tidal flats, and beaches, as well as irrigated fields, pastures, and urban landfills. It frequently works the air over swarms of flying insects and patrols surf lines and harbors for fish and scraps.
