California Gull

The California Gull is a medium-large gull that nests in huge colonies on isolated islands within interior lakes of the western United States and Canada, then disperses to the Pacific coast for the winter. Adults have a medium gray mantle, slightly darker than a Ring-billed Gull but paler than a Western Gull, with a white head, neck, and underparts.

The bill is yellow with both a red and a black spot near the tip, a helpful distinguishing feature, and the legs are yellow-green to greenish-yellow, sometimes appearing dull yellow. The dark eye gives the face a somewhat softer look than some pale-eyed relatives.

This species holds a special place in American folklore as the state bird of Utah, commemorated for a event in 1848 known as the "Miracle of the Gulls," when large flocks reportedly descended on farmland to consume a swarm of Mormon crickets that threatened the survival of early settlers' crops.

Key field marks

• Medium gray mantle, darker than Ring-billed Gull but paler than Western Gull
• Yellow bill with both a red and a black spot near the tip
• Yellow-green to dull yellow legs
• Dark eye
• Medium-large, fairly slender build

Similar species

• Ring-billed Gull: smaller, paler mantle, yellow bill with a single black ring (no red spot), pale eye.
• Herring Gull: larger, pinkish legs, paler mantle, bill with only a red spot (no black spot).
• Western Gull: noticeably darker mantle and heavier bill, restricted to the immediate Pacific coast.

Habitat

Breeds colonially on islands in large interior lakes, reservoirs, and marshes across the western United States and southwestern Canada, including famous colonies at Utah's Great Salt Lake and California's Mono Lake. Winters along the Pacific coast in bays, beaches, harbors, and agricultural fields.

Range and migration

Breeding range spans the interior western United States and adjacent Canada; most birds migrate to the Pacific coast from British Columbia south to Mexico for the non-breeding season.

Behavior

Highly social and opportunistic, California Gulls forage over farmland, landfills, and lakes, and are notable predators of the eggs and chicks of other colonial waterbirds at their breeding lakes.

Voice

Calls include a range of typical large-gull notes: harsh, laughing "kyow" calls and long calls given with head thrown back during territorial and courtship displays.

Feeding

Opportunistic and varied, including insects (notably brine flies and crickets at alkaline lakes), fish, small mammals, eggs and chicks of other birds, and refuse.

Nesting and breeding

Nests in dense colonies, often on predator-free islands within large lakes, building a ground scrape lined with vegetation. Clutches typically contain two to three eggs, incubated by both parents for about three to four weeks.