California Gull

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iCalifornia Gull

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Laridae
Genus:	Larus
Species:	L. californicus

Binomial name

Larus californicus
(Lawrence, 1854)

Subspecies

L. c. californicus Lawrence, 1854
Great Basin California Gull
L. c. albertaensis Jehl, 1987
Great Plains Galifornia Gull

The California Gull, Larus californicus, is a medium-sized gull, smaller than the Herring Gull but larger than the Ring-billed Gull.

Adults are similar in appearance to the Herring Gull, but have a smaller yellow bill with a black ring, yellow legs, brown eyes and a more rounded head. The body is mainly white with grey back and upper wings. They have black primaries with white tips. Immature birds are also similar in appearance to immature Herring Gulls, with browner plumage than immature Ring-billed Gulls.

Their breeding habitat is lakes and marshes in western North America. They nest in colonies, sometimes with other birds. The nest is a shallow depression on the ground lined with vegetation and feathers. The female usually lays 2 or 3 eggs. Both parents feed the young birds.

They are migratory, most moving to the Pacific coast in winter. Indeed, it is only then that this bird is regularly found in California.

These birds forage in flight or pick up objects while swimming, walking or wading. They mainly eat insects, fish and eggs. They also scavenge at garbage dumps or docks. They may follow plows in fields for insects stirred up by this activity.

This is the state bird of Utah, remembered for assisting Mormon settlers in dealing with a plague of Mormon crickets. A Seagull Monument in Salt Lake City commemorates this event, known as the "Miracle of the Gulls".

There are 2 subspecies recognized, the nominate from the Great Basin to central Montana and Wyoming, and the larger, paler L. c. albertaensis with a more inland distribution, ranging from Great Slave Lake onto the Great Plains of western Manitoba and South Dakota (Jehl, 1987). Although these subspecies are not well distinguishable by mtDNA allozyme variation (Karl et al., 1987), they breed true and the low genetic divergence can be explained by separation during the Pleistocene and renewed contact in Montana during more recent times (Jehl et al., 1990).

[edit] References

BirdLife International (2004). Larus californicus. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes justification for why this species is of least concern

Burger, Joanna & Gochfeld, Michael (1996): 13. California Gull. In: del Hoyo, Josep; Elliott, Andrew & Sargatal, Jordi (editors): Handbook of Birds of the World, Volume 3: Hoatzin to Auks: 604-605, plate 50. Lynx Edicions, Barcelona. ISBN 84-87334-20-2

Harrison, Peter (1991): Seabirds: An Identification Guide. Houghton Mifflin.

Jehl, Joseph R. Jr. (1987): Geographic variation and evolution in the California Gull (Larus californicus). Auk 104(3): 421–428. PDF fulltext

Jehl, Joseph R. Jr.; Francine, J; Bond, S. I. (1990): Growth patterns of two races of California Gulls raised in a common environment. Condor 92(3): 732–738. PDF fulltext

Karl, S. A.; Zink, R. M.; Jehl, Joseph R. Jr. (1987): Allozyme analysis of the California Gull (Larus californicus). Auk 104(4): 767–769. PDF fulltext

National Geographic Society (2002): Field Guide to the Birds of North America. National Geographic, Washington DC. ISBN 0-792-26877-6

Sibley, David Allen (2000): The Sibley Guide to Birds. Alfred A. Knopf, New York. ISBN 0-679-45122-6

Winkler, D. W. (1996): California Gull (Larus californicus). In: Poole, A. & Gill, F.: The Birds of North America 259. The Academy of Natural Sciences, Philadelphia, PA & The American Ornithologists' Union, Washington, D.C.