California Gull (Larus californicus)

[order] CHARADRIIFORMES | [family] Laridae | [latin] Larus californicus | [UK] California Gull | [FR] Goeland de Californie | [DE] Kaliforniermowe | [ES] Gaviota Californiana | [NL] Prairie-meeuw

Subspecies

Genus Species subspecies Breeding Range Breeding Range 2 Non Breeding Range
Larus californicus NA, MA nc, w
Larus californicus albertaensis c Canada, nc and nw USA sw Canada to sw Mexico
Larus californicus californicus nw USA to s Mexico

Physical charateristics

Abundant in the West. Adult: Resembles the smaller Ring-billed Gull (both may have yellowish green legs or not), but note the darker mantle, darker eye, and red and black spot
on the lower mandible (not a black ring). Shows more white in wingtips than the Ring-bill does.

Listen to the sound of California Gull

[audio:http://www.aviflevoland.nl/sounddb/C/California Gull.mp3]

Copyright remark: Most sounds derived from xeno-canto

wingspan min.: 125 cm wingspan max.: 135 cm
size min.: 47 cm size max.: 54 cm
incubation min.: 23 days incubation max.: 27 days
fledging min.: 2 days fledging max.: 4 days
broods: 1   eggs min.: 1  
      eggs max.: 4  

Range

North America, Middle America : nc, West

Habitat

Seacoasts, lakes, farms, urban centers.
Breeds in the interior at lakes and marshes, often foraging for insects around farms, plowed fields. Some winter inland around major lakes and rivers, but most are coastal at that season, frequenting beaches, docks, garbage dumps, fields. Sometimes commo
n well offshore in winter.

Reproduction

Breeds in colonies, sometimes very large, and sometimes mixed with Ring-billed Gulls or other birds; the nests may be quite close together. Court
ship involves various postures and calls; male displays with upright posture, “choking” motions. Also courtship feeding, with male feeding female.
Nest: Site is on ground near lake or marsh, often on island. Nest (built by both sexes) is shallow depression, usually lined with weeds, grass, debris, feathers.
Eggs: 2-3, sometimes 1-5. Clutches of more than 3 result from 2 females laying in same nest. Eggs brown, olive, gray, or buff, blotched with dark brown or gray. Incubation by both parents, 23-27 days.
Young: May leave nest when a few days old, but remain in immediate area. Both parents feed young, by regurgitation. Young can fly at about 45 days after hatching.

Feeding habits

Varied; includes insects, fish, eggs, refuse. Summer diet inland is mostly insects; also worms, spiders, rodents, eggs
and young of other birds, and carrion. On coast, eats fish and other marine life, also scavenges for refuse around garbage dumps, fishing piers.
Behavior: Forages while walking, wading, swimming, or flying. May hover and dip down to pick items from surface of land or water. Sometimes follows plow in farm fields to pick up insects exposed in the furrows.

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
California Gull status Least Concern

Migration

Mainly western North America, east to central North Dakota. Migration:
From breeding grounds in interior, most migrate west or southwest to Pacific coast. Surprisingly few move south to Gulf coast; extremely rare east to Atlantic coast. Birds too young to breed may remain along Pacific coast through the summer.

Distribution map

California Gull distribution range map

California Gull distribution range map

Leave a Reply

Your email address will not be published. Required fields are marked *