A practical guide to bird watching in Sonoma County, California

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


Our crestless jay. Western Scrub-jay is found just about everywhere in the county, from coastal scrubland to heavily wooded inland areas at lower elevations to suburban backyards. Common at bird feeders. Less common in thick coniferous forests and at higher elevations, however, where its place is taken by Steller's Jay (Cyanocitta stelleri). Western Scrub-jay is among our most common birds.

Often seen perched high in a tall shrub surveying the surrounding land. Prefers insects for food, but will eat most anything, especially acorns. Will attempt to steal the eggs of other birds. Buries acorns for winter use. This bird is probably responsible for many of the oaks planted in the areas it inhabits, as it frequently forgets a percentage of the acorns it stashes--despite prodigious powers of recall. Can be loud and aggressive around a nesting site, or when dominating a bird feeder. Sometimes becomes semi-tame around parks and campgrounds where it will attempt to steal food. Often heard before it's seen, making its distinctive Shreeenk! call.

Fairly easily recognized by its fairly large size, broad "shoulders," bright blue color, and long tail, although when perched and seen at a distance, it is often the bird’s whitish breast and belly that draw the eye. Has a distinctive way of flying (rapid wingbeats followed by long glides on stiff wings) and an equally distinctive way of coming in for a heavy landing. Once you know this bird, it's among the easiest to pick out, just by its silhouette and behavior or by voice. The two sexes look alike. Juvenile birds have grey heads and lack the white eyebrow of the adult (see below). Separated from Steller's Jay by its lack of a crest, paler blue mixed with white and gray, and different vocalizations. Range does not overlap with the ranges of other somewhat similar jays. Beginners may confuse Western Scrub-jay with Western Bluebird (Sialia mexicana), which is a considerably smaller, quieter bird with rufous sides and entirely different habits. Note that the illustration in the popular Birds of Northern California (Fix and Bezener, 2000) and some other field guides show this bird with a large, nearly black ear patch (as in the bird featured at the top of this page, but the patch is not so dark and contrasting in many Western Scrub-jays we see. Many have a greyish ear patch. Coloration is generally variable--particularly the ear patch and the extent of the blue at the upper breast in our coastal subspecies (see below). A dark grey to black ear patch is absent, for example, in the bird shown below.

Two major subspecies are recognized, the coastal form (Aphelocoma californica californica) and the inland form (Aphelocoma californica woodhouseii, Woodhouse's Srub-jay). Our birds are of the coastal form, which is a brighter blue than the inland subspecies, and has much more blue on the sides of the upper breast on either side of the splotchy white at the throat. Interior populations are said to be relatively shy. Other interior subspecies are recognized as well. Western Scrub-jay is very closely related to Island Scrub-jay (Aphelocoma insularis), which is restricted to Santa Cruz Island in southern California.

Listed in older books such as Sonoma County Breeding Bird Atlas (1995), and The Birder's Handbook (1988) as Scrub Jay Aphelocoma coerulescens. That Latin name is now assigned to Florida Scrub-jay, which is restricted to central Florida. Scrub Jay (Aphelocoma coerulescens) was split into Western Scrub-jay, Florida Scrub-jay, and Island Scrub-jay by the American Ornithological Union in 1996.

Further reading:

Bolander and Parmeter, Birds of Sonoma County California, rev. ed., 2000, p. 87

Brinkley, National Wildlife Federation Field Guide to Birds of North America, 2007, p. 410

Burridge, ed., Sonoma County Breeding Bird Atlas, 1995, p. 113

Dunn and Alderfer, eds., National Geographic Field Guide to the Birds of North America, 5th ed., 2006, p. 320

Dunn and Alderfer, eds., National Geographic Field Guide to the Birds of North America, 6th ed., 2011, p. 360

Dunne, Pete Dunne’s Essential Field Guide Companion, 2006, pp. 441-442

Ehrlich, Dobkin, and Wheye, The Birder's Handbook, paperback edition, 1988, p. 404

Fix and Bezener, Birds of Northern California, 2000, p. 261

Floyd, Smithsonian Field Guide to the Birds of North America, 2008, p. 313

Kaufman, Field Guide to Birds of North America, 2000, p. 274

Kaufman, Field Guide to Advanced Birding, 2011, pp. 12

Lukas, Bay Area Birds: From Sonoma County to Monterey Bay, 2012, pp. 190-191

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

Peterson, Field Guide to Birds of Western North America, 4th ed., 2010, p. 262

Peterson, Western Birds, 3rd ed., 1990,  p. 254

Sibley, Field Guide to Birds of Western North America,1st ed., 2003, p. 304

Stokes, Stokes Field Guide to the Birds of North America, 1st ed., 2010, p. 501

Vuilleumier, American Museum of Natural History, Birds of North America: Western Region, 2011, p. 275

Voice: Cornell Lab of Ornithology: All About Birds--Western Scrub-jay

Voice: Cornell Lab of Ornithology: All About Birds--Steller's Jay



© Colin Talcroft, 2009, 2010, 2011, 2012, 2013, 2014, 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.


Western Scrub-jay, Campbell Cove, Bodega Bay

September 10, 2010

Juvenile Western Scrub-jay. Note: grey head and nape, lack of strong white eyebrow of the adult plumage.

Spring Lake, Santa Rosa, June 18, 2011

Western Scrub-jay

Aphelocoma californica

1990-2013 Sonoma County data. Graph provided by eBird (www.ebird.org), generated September 21, 2013

EBird reported occurrence in Sonoma County

Western Scrub-jay, Bodega Bay, January 19, 2015