A practical guide to bird watching in Sonoma County, California

(Unless otherwise indicated, all phone numbers are in the 707 area code)


One of our more common gulls. Certainly the most common at ports, docks, and around seaside human activity. Adults in breeding plumage, like the bird pictured above, are not hard to identify, but Western gulls take four years to attain full adult plumage, and the juvenile and intermediate stages can be very confusing. My best advice is to study the birds you see and study the books, particularly Gulls of the Americas (see below); eventually, patterns begin to emerge. I'm getting better at identifying gulls, but I am still at the intermediate level at best. I believe the notes here are accurate, but gulls are very good at making people feel ignorant. Please feel free to point out errors or omissions. If in doubt, check the books.

The typical adult in breeding plumage is characterized by a heavy school bus-yellow bill with a pronounced widening toward the tip (the gonys) usually marked by a red spot. Unlike many other common gulls in Sonoma County, the head and breast remain clear white in the winter (most gulls become streaked with various shades of brownish grey in the winter). Note the pink legs and darkish gray back (the mantle)--although color can be difficult to judge in different lights and there is a great deal of color variation from bird to bird and among different populations (northern California Western Gulls tend to be lighter grey). In breeding plumage, Western Gull has a bright yellow-orange eye ring. The eye itself is fairly dark (see photo below). The primaries are tipped with black but have small, distinct, white "mirrors." Juvenile birds are mostly brown. See the usual guide books and Gulls of the Americas for the progression of plumage changes through the four years to maturity. The only gull that breeds in Sonoma County. Often nests off Bodega Head.

Perhaps most likely to be confused with Herring Gull, but Herring Gull has a straighter bill profile (less of the bump at the tip), the bill is a clearer yellow (less orange), the mantle will tend to be paler, the "mirrors" in the primaries will be bigger, and Herring Gull has a pale eye (with a pale yellow eye ring in breeding plumage), although at a distance or in flight, details of the eye are not very useful and eye color is somewhat variable. In winter, Herring Gull will have a streaked head.

Also see: A comparison of common gull heads in breeding and non-breeding plumages   

Further reading:

Bolander and Parmeter, Birds of Sonoma County California, rev. ed., 2000, p. 63

Brinkley, National Wildlife Federation Field Guide to Birds of North America, 2007, p. 130

Burridge, ed., Sonoma County Breeding Bird Atlas, 1995, pg 72.

Dunn and Alderfer, eds., National Geographic Field Guide to the Birds of North America, 5th ed., 2006, pg. 210

Dunn and Alderfer, eds., National Geographic Field Guide to the Birds of North America, 6th ed., 2011, pg. 228

Dunne, Pete Dunne’s Essential Field Guide Companion, 2006, pp. 267-268

Howell and Dunn, Gulls of the Americas, 2007, pp. 34-43, 221-225, 442-447

Ehrlich, Dobkin, and Wheye, The Birder's Handbook, paperback edition, 1988, pg. 174

Fix and Bezener, Birds of Northern California, 2000, p. 178

Floyd, Smithsonian Field Guide to the Birds of North America, 2008, p. 190

Kaufman, Field Guide to Birds of North America, 2000, p. 80

Kaufman, Advanced Birding, 1990, pp. 102-108 (general notes on gull ID)

Kaufman, Field Guide to Advanced Birding, 2011, pp. 242-263 (general notes on gull ID)

Lukas, Bay Area Birds: From Sonoma County to Monterey Bay, 2012, pp. 124-125

Parmeter and Wight, Birds of Sonoma County California, Update (2000-2010), 2012, p. 35

Peterson, Field Guide to Birds of Western North America, 4th ed., 2010, pp. 178, 182

Peterson, Western Birds, 3rd ed., 1990,  pp. 88, 90, 98

Sibley, Field Guide to Birds of Western North America,1st ed., 2003, p. 194

Stokes, Stokes Field Guide to the Birds of North America, 1st ed., 2010, p. 314-315

Vuilleumier, American Museum of Natural History, Birds of North America: Western Region, 2011, p. 169

Voice: Cornell Lab of Ornithology: All About Birds--Western Gull



© Colin Talcroft, 2009 - 2015

Unless noted, all photos by the author. If you would like to use one of my images, please ask for permission for non-commercial use with proper credit or commercial use with proper compensation.


Adult Western Gull in breeding plumage: Note yellow-orange orbital ring, darkish iris, bulbous bill tip, red spot, clear white head

Adult Western Gull in breeding plumage, Bodega Head, Bodega Bay, April 24, 2012

Western Gull swallowing a star fish whole (successfully)

Doran Beach, Bodega Bay, September 13, 2012

Western Gull

Larus occidentalis

1990-2013 Sonoma County data. Graph provided by eBird (www.ebird.org), generated September 18, 2013

EBird reported occurrence in Sonoma County

Adult Western Gull in flight, Bodega Head, April 2, 2015