Larus californicus - Lawrence, 1854
California Gull
Taxonomic Status: Accepted
Related ITIS Name(s): Larus californicus Lawrence, 1854 (TSN 176829)
French Common Names: goéland de Californie
Spanish Common Names: Gaviota Californiana
Unique Identifier: ELEMENT_GLOBAL.2.100812
Element Code: ABNNM03110
Informal Taxonomy: Animals, Vertebrates - Birds - Other Birds
Image 10717

© Dick Cannings

 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Aves Charadriiformes Laridae Larus
Genus Size: D - Medium to large genus (21+ species)
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Concept Reference
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Concept Reference: American Ornithologists' Union (AOU). 1998. Check-list of North American birds. Seventh edition. American Ornithologists' Union, Washington, D.C. [as modified by subsequent supplements and corrections published in The Auk]. Also available online: http://www.aou.org/.
Concept Reference Code: B98AOU01NAUS
Name Used in Concept Reference: Larus californicus
Taxonomic Comments: Closely interrelated with L. argentatus, L. cachinnans, L. thayeri, L. glaucoides, and L. fuscus (AOU 1998).
Conservation Status
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NatureServe Status

Global Status: G5
Global Status Last Reviewed: 09Apr2016
Global Status Last Changed: 27Nov1996
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Nation: United States
National Status: N5B,N5N (05Jan1997)
Nation: Canada
National Status: N5B,NUN,N5M (08Jan2018)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Alaska (S3N), Arizona (S3N), California (S4), Colorado (S4B), Idaho (S3B, S2N), Montana (S5B), Navajo Nation (S3N), Nebraska (SNRN), Nevada (S5B), New Mexico (S4N), North Carolina (SNA), North Dakota (SNRB), Oregon (S5), South Dakota (S2B), Texas (SNA), Utah (S5), Washington (S4B,S5N), Wyoming (S2B)
Canada Alberta (S5B), British Columbia (S2S3B), Manitoba (S4B), Northwest Territories (S4B), Ontario (SNA), Saskatchewan (S5B,S5M)

Other Statuses

IUCN Red List Category: LC - Least concern

NatureServe Global Conservation Status Factors

Range Extent Comments: BREEDS: interior North America from southern Mackenzie, Saskatchewan, and Manitoba south to east-central North Dakota, central Montana, northwestern Wyoming, eastern Idaho, northwestern Utah, northwestern Nevada, eastern California, southeasternuthern Washington. The largest nesting concentration (about 130,000-150,000 in 1988-1991) occurs around the Great Salt Lake, Utah (Paton et al. 1992). WINTERS: southern Washington, eastern Idaho, south along Pacific coast to southern Baja California northwestern Mexico; rare in Hawaii.

Other NatureServe Conservation Status Information

Distribution
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Global Range: BREEDS: interior North America from southern Mackenzie, Saskatchewan, and Manitoba south to east-central North Dakota, central Montana, northwestern Wyoming, eastern Idaho, northwestern Utah, northwestern Nevada, eastern California, southeasternuthern Washington. The largest nesting concentration (about 130,000-150,000 in 1988-1991) occurs around the Great Salt Lake, Utah (Paton et al. 1992). WINTERS: southern Washington, eastern Idaho, south along Pacific coast to southern Baja California northwestern Mexico; rare in Hawaii.

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
NOTE: The maps for birds represent the breeding status by state and province. In some jurisdictions, the subnational statuses for common species have not been assessed and the status is shown as not-assessed (SNR). In some jurisdictions, the subnational status refers to the status as a non-breeder; these errors will be corrected in future versions of these maps. A species is not shown in a jurisdiction if it is not known to breed in the jurisdiction or if it occurs only accidentally or casually in the jurisdiction. Thus, the species may occur in a jurisdiction as a seasonal non-breeding resident or as a migratory transient but this will not be indicated on these maps. See other maps on this web site that depict the Western Hemisphere ranges of these species at all seasons of the year.
Endemism: occurs (regularly, as a native taxon) in multiple nations

U.S. & Canada State/Province Distribution
United States AK, AZ, CA, CO, ID, MT, NC, ND, NE, NM, NN, NV, OR, SD, TX, UT, WA, WY
Canada AB, BC, MB, NT, ON, SK

Range Map
Note: Range depicted for New World only. The scale of the maps may cause narrow coastal ranges or ranges on small islands not to appear. Not all vagrant or small disjunct occurrences are depicted. For migratory birds, some individuals occur outside of the passage migrant range depicted. For information on how to obtain shapefiles of species ranges see our Species Mapping pages at www.natureserve.org/conservation-tools/data-maps-tools.

Range Map Compilers: NatureServe, 2002; WILDSPACETM 2002


U.S. Distribution by County Help
State County Name (FIPS Code)
CA Imperial (06025), Lassen (06035), Modoc (06049), Mono (06051), Siskiyou (06093)
ID Ada (16001), Adams (16003), Bannock (16005), Bear Lake (16007), Benewah (16009), Bingham (16011), Blaine (16013), Boise (16015), Bonner (16017), Bonneville (16019), Boundary (16021), Butte (16023), Camas (16025), Canyon (16027), Caribou (16029), Cassia (16031), Clark (16033), Clearwater (16035), Custer (16037), Elmore (16039), Franklin (16041), Fremont (16043), Gem (16045), Gooding (16047), Idaho (16049), Jefferson (16051), Jerome (16053), Kootenai (16055), Latah (16057), Lemhi (16059), Lewis (16061), Lincoln (16063), Madison (16065), Minidoka (16067), Nez Perce (16069), Oneida (16071), Owyhee (16073), Payette (16075), Power (16077), Shoshone (16079), Twin Falls (16083), Valley (16085), Washington (16087)
SD Butte (46019), Codington (46029), Day (46037), Dewey (46041), Marshall (46091), McPherson (46089), Meade (46093), Stanley (46117)
WY Albany (56001), Big Horn (56003), Carbon (56007), Converse (56009), Crook (56011), Fremont (56013), Goshen (56015), Johnson (56019), Laramie (56021), Lincoln (56023), Natrona (56025), Park (56029), Platte (56031), Sublette (56035), Sweetwater (56037), Teton (56039), Uinta (56041), Weston (56045)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
10 Yellowstone Headwaters (10070001)+, Clarks Fork Yellowstone (10070006)+, Upper Wind (10080001)+, Little Wind (10080002)+, Popo Agie (10080003)+, Lower Wind (10080005)+, Big Horn Lake (10080010)+, Dry (10080011)+, North Fork Shoshone (10080012)+, South Fork Shoshone (10080013)+, Shoshone (10080014)+, South Fork Powder (10090203)+, Salt (10090204)+, Clear (10090206)+, Antelope (10120101)+, Dry Fork Cheyenne (10120102)+, Beaver (10120107)+, Middle Cheyenne-Elk (10120111)+, Upper Belle Fourche (10120201)+, Lower Belle Fourche (10120202)+, Redwater (10120203)+, Lower Lake Oahe (10130105)+, West Missouri Coteau (10130106)+, Upper James (10160003)+, Middle Big Sioux Coteau (10170201)+, Upper North Platte (10180002)+, Pathfinder-Seminoe Reservoirs (10180003)+, Medicine Bow (10180004)+, Little Medicine Bow (10180005)+, Sweetwater (10180006)+, Middle North Platte-Casper (10180007)+, Glendo Reservoir (10180008)+, Middle North Platte-Scotts Bluff (10180009)+, Upper Laramie (10180010)+, Lower Laramie (10180011)+, Horse (10180012)+, Cache La Poudre (10190007)+, Crow (10190009)+, Upper Lodgepole (10190015)+
14 Upper Green (14040101)+, New Fork (14040102)+, Upper Green-Slate (14040103)+, Big Sandy (14040104)+, Bitter (14040105)+, Upper Green-Flaming Gorge Reservoir (14040106)+, Blacks Fork (14040107)+, Muddy (14040108)+, Vermilion (14040109)+, Great Divide closed basin (14040200)+, Little Snake (14050003)+, Muddy (14050004)+
16 Upper Bear (16010101)+, Central Bear (16010102)+, Bear Lake (16010201)+, Middle Bear (16010202)+, Little Bear-Logan (16010203)+, Lower Bear-Malad (16010204)+, Curlew Valley (16020309)+
17 Lower Kootenai (17010104)+, Lower Clark Fork (17010213)+, Pend Oreille Lake (17010214)+, South Fork Coeur D'alene (17010302)+, Coeur D'alene Lake (17010303)+, St. Joe (17010304)+, Upper Spokane (17010305)+, Snake headwaters (17040101)+, Gros Ventre (17040102)+, Greys-Hobock (17040103)+, Palisades (17040104)+, Salt (17040105)+, Idaho Falls (17040201)+, Upper Henrys (17040202)+, Lower Henrys (17040203)+, Teton (17040204)+, Willow (17040205)+, American Falls (17040206)+, Blackfoot (17040207)+, Portneuf (17040208)+, Lake Walcott (17040209)+, Raft (17040210)+, Goose (17040211)+, Upper Snake-Rock (17040212)+, Salmon Falls (17040213)+, Beaver-Camas (17040214)+, Medicine Lodge (17040215)+, Big Lost (17040218)+, Big Wood (17040219)+, Camas (17040220)+, Little Wood (17040221)+, C. J. Idaho (17050101)+, Bruneau (17050102)+, Middle Snake-Succor (17050103)+, Upper Owyhee (17050104)+, Jordan (17050108)+, Boise-Mores (17050112)+, South Fork Boise (17050113)+, Lower Boise (17050114)+, Middle Snake-Payette (17050115)+, Payette (17050122)+, North Fork Payette (17050123)+, Weiser (17050124)+, Brownlee Reservoir (17050201)+, Hells Canyon (17060101)+, Lower Snake-Asotin (17060103)+, Lower Snake-Tucannon (17060107)+, Palouse (17060108)+, Upper Salmon (17060201)+, Middle Salmon-Panther (17060203)+, Lemhi (17060204)+, Clearwater (17060306)+, Lower North Fork Clearwater (17060308)+
18 Lost (18010204)+, Shasta (18010207)+, Goose Lake (18020001)+, Honey-Eagle Lakes (18080003)+, Mono Lake (18090101)+, Salton Sea (18100204)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Reproduction Comments: Breeding begins late April in south to early June in north. Both sexes incubate 3 eggs for 23-27 days. Semi-precocial young are tended by both parents. In southern California, fledging was almost complete by the end of July. May form female-female pairs.
Ecology Comments: May gather in large flocks, often in association with Herring and Ring-billed Gulls. Great Horned Owl may cause significant mortality in breeding colony (California, Jehl and Mahoney 1987). Home range: breeding pairs in Montana foraged an average of 17.4 kilometers (maximum 61 kilometers) from colony (Baird 1976). At another colony, maximum foraging distance was 32 kilometers (Rothweiler 1960).
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: Y
Marine Habitat(s): Near shore, Pelagic
Estuarine Habitat(s): Bay/sound, Herbaceous wetland, Lagoon, River mouth/tidal river, Tidal flat/shore
Riverine Habitat(s): BIG RIVER, MEDIUM RIVER
Lacustrine Habitat(s): Deep water, Shallow water
Palustrine Habitat(s): HERBACEOUS WETLAND, Riparian, TEMPORARY POOL
Terrestrial Habitat(s): Cropland/hedgerow, Sand/dune, Suburban/orchard, Urban/edificarian
Habitat Comments: Seacoasts, bays, estuaries, mudflats, marshes, irrigated fields, lakes, ponds, dumps, cities, and agricultural lands (AOU 1983). Nests inland on open sandy or gravelly areas on islands or along shores of lakes and ponds, generally with scattered grasses. Nests on ground. Prefers fairly open area with irregular terrain near shore of islands (Jehl and Mahoney 1987). NON-BREEDING: In autumn migration, the most abundant gull in pelagic waters off the British Columbia and Washington coast (Campbell 1990).
Adult Food Habits: Carnivore, Invertivore, Piscivore
Immature Food Habits: Carnivore, Invertivore, Piscivore
Food Comments: In inland areas, feeds on insects (crickets, grasshoppers, cutworms) and mice. At Mono Lake, California, recently fledged gulls fed mainly on, and aparently preferred, alkali flies (Elphick and Rubega 1995, Great Basin Nat. 55:363-367). Along the coast, feeds on dead fish and garbage; scavenges behind boats, around harbors and dumps.
Adult Phenology: Diurnal
Immature Phenology: Diurnal
Colonial Breeder: Y
Length: 53 centimeters
Weight: 609 grams
Economic Attributes Not yet assessed
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Management Summary Not yet assessed
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Population/Occurrence Delineation
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Group Name: Gulls and Terns

Use Class: Adult foraging area
Minimum Criteria for an Occurrence: Applies to both adults and juveniles. Evidence of one or more individuals seeking food in suitable habitat. Evidence of prey capture is not a prerequisite, as importance of a given location for foraging may vary temporally with shifting prey.
Separation Distance for Unsuitable Habitat: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Scientific basis for assigning foraging separation distances is weak because terns are widespread across the Massachusetts coast and highly mobile. Most gaps in foraging observations likely reflect lack of survey effort.
Date: 10Jan2017
Author: Mostello, C. S.

Use Class: Breeding
Minimum Criteria for an Occurrence: Evidence of historical breeding, or current and likely recurring breeding, at a given location, minimally a reliable observation of one or more breeding pairs in appropriate habitat. Be cautious about creating EOs for observations that may represent single breeding events outside the normal breeding distribution.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Occurrences include nesting areas and associated nesting-season foraging areas (regardless of how far apart they are), but separation distance pertains to nesting areas (breeding colonies). Thus different breeding occurrences may overlap if birds from different nesting areas forage in the same area. Separation distance is not intended to delineate demographically independent populations or metapopulations (such units would be quite large). Instead, separation distance is a compromise between the high mobility of these birds (see following) and the need for occurrences that are of practical size for conservation/management use.

California Gulls foraged an average of 17.4 kilometers from colony (Baird 1976); maximum foraging distances ranged from 32 to 61 kilometers (Rothweiler 1960, Baird 1976). Ring-billed Gulls foraged an average of 11 km from colony (Baird 1977). Least Terns foraged up to 3-12 kilometers from nests (summarized in Thompson et al. 1997). Forster's Terns has a reported feeding radius of 3.2 kilometers (Van Rossem 1932). Black Terns foraged up to 10 kilometers from nests, over continuous suitable but unoccupied habitat (M. A. Stern, pers. comm. 1998). Caspian terns in a colony at the mouth of the Columbia River: 90% of adults foraged within 21 kilometers (Collis et al. 1999).

Date: 21Jul2004
Author: Cannings, S., and G. Hammerson

Use Class: Migratory stopover
Minimum Criteria for an Occurrence: Evidence of recurring presence of migrating flocks (including historical); and potential recurring presence at a given location, minimally a reliable observation of 50 birds in appropriate habitat. Occurrences should be locations where the species is resident for some time during the appropriate season; it is preferable to have observations documenting presence over at least 7 days annually. Be cautious about creating EOs for observations that may represent single events.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Separation distance somewhat arbitrary; set such that occurrences are of managable size for conservation purposes. Occurrences are defined primarily on the basis of areas supporting concentrations of foraging birds, rather than on the basis of distinct populations.
Date: 26Apr2004

Use Class: Nonbreeding
Subtype(s): Foraging Concentration Area
Minimum Criteria for an Occurrence: Evidence of recurring presence of wintering flocks (including historical); and potential recurring presence at a given location, minimally a reliable observation of 25 birds in appropriate habitat. Occurrences should be locations where the species is resident for some time during the appropriate season; it is preferable to have observations documenting presence over at least 20 days annually. Be cautious about creating EOs for observations that may represent single events.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Separation distance somewhat arbitrary; set such that occurrences are of managable size for conservation purposes. Occurrences are defined primarily on the basis of areas supporting concentrations of foraging birds, rather than on the basis of distinct populations.
Date: 16Apr2002
Author: Cannings, S.
Notes: Includes all inland-nesting gulls and terns, in the genera LARUS, STERNA, and CHLIDONIAS.

Use Class: Staging
Minimum Criteria for an Occurrence: Evidence of flocks resting, roosting, and/or feeding young at a given location prior to breeding or after breeding has been completed. Staging may occur near the breeding site, preceding or following major migratory movements such as oceanic crossings, or it may occur after individuals have departed on migration, but before they have arrived at their final destination (a "stopover"). Staging may occur at sites also used for breeding, but often does not. Staging habitat may be ephemeral. For Common/Roseate Terns in Massachusetts, a minimum of 100 individuals in appropriate habitat is used.
Separation Distance for Unsuitable Habitat: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: In Massachusetts, staging areas are separated somewhat arbitrarily, often by jurisdictional or property boundaries, as are nesting areas for coastal birds.
Date: 10Jan2017
Author: Mostello, C. S.
Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
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Authors/Contributors
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Element Ecology & Life History Edition Date: 24Mar1994
Element Ecology & Life History Author(s): HAMMERSON, G., REVISIONS BY S. CANNINGS

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

References
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  • Vermeer, K. 1970. Breeding biology of California and Ring-Billed Gulls. Can. Wild. Serv. Rep. Ser. No. 12, Ottawa, ON. 52pp.

  • Wildlife Management Information System (WMIS). 2006+. Geo-referenced wildlife datasets (1900 to present) from all projects conducted by Environment and Natural Resources, Government of the Northwest Territories, Canada.  Available at http://www.enr.gov.nt.ca/programs/wildlife-research/wildlife-management-information-services

  • Winkler, D.W. 1996. California Gull (Larus californicus). in A. Poole, and F. Gill, eds. The Birds of North America, No. 259. Acad. Nat. Sci., Philadelphia, PA, and Am. Ornithol. Union, Washington, DC. 28pp.

  • Winkler, D.W. 1996. California Gull (Larus californicus). In: A. Poole and F. Gill, (eds.). The Birds of North America, No.259. The Academy of Natural Sciences, Philadelphia, and The American Ornithologists Union, Washington, D.C.

  • Wyoming Game and Fish Department. 1993. Endangered and nongame bird and mammal investigations: Annual completion report. Wyoming Game and Fish Department - Nongame Program, Biological Services Section. 197 p.

  • Yochem, P.K. 1991. Distribution and History of California Gull Colonies in Nevada. Western Birds. V.22. pp.1-12.

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