Western Scrub Jay
Jacob A. R. Berg (2001)

Aphelocoma californica

The Western Scrub Jay (Aphelocoma californica) is actually a relatively new species. There are three species of scrub jays that were formally believed to be races of a single species. The Island scrub jay (Aphelocoma insularis) is only found on the island of Santa Cruz off the coast of California. The Florida scrub jay (Aphelocoma coerulescens) is endemic to Florida. The Western scrub jay, of which this report shall pertain to, is found from coastal northern Washington and down the coast to California. The species can be found as far east as Colorado and parts of Texas, but is most common in the Pacific states. They are commonly found around areas with stunted trees such as mesquite, scrub oak, pinyon pine, juniper, and thick, low brush. They can also be found near suburban yards or wooded city parks. At least one lives on the Willamette Campus near Doney.

They can be recognized by their distinctive blue head, wings, and tail. Their back is dull brown, stomach is light gray, and their throat is white with an incomplete blue ‘necklace.’ They are about the same size as a robin (11-13” in length), but their long strong bill and relatively large tail make them appear larger. Inland, the blue on the back is much duller than those found in coastal regions. Both sexes look the same and juveniles are more dull in color appearing grayish above with blue wings and tail. Western scrub jays can be confused with Mexican or gray-breasted jays (Aphelocoma ultramarine) which occur in southern Arizona and parts of Texas. However, the Mexican jay is more uniformly bluish gray above and grayish white below and lacks the incomplete ‘necklace’ apparent in the Western scrub jay.

The Western scrub jay eats small birds, eggs, acorns, nuts, grain, berries, and insects. They are commonly labeled as ‘nest robbers’ in the summer although they are primarily insectivorous. Western scrub jays are extremely fond of acorns. They will often gather and bury as many acorns as they can find. This is usually far more than any bird can consume so many of these acorns become oak trees. Western scrub jays are instrumental in reforestation of oak forests after fires or droughts as well as transporting trees up hills that acorns would usually just roll down.

In the morning, or while it is around the nest, the Western scrub jay can be extremely quiet. However, like all corvids, the Western scrub jay is capable of making loud annoying calls. While perched, the calls sound like a throaty “jayy” or “jree” and in flight the call sounds like “check-check-check.” I found no indication if the Western scrub jay could imitate hawks like some other jays (namely the Stellar Jay) have been known to do.

The Western scrub jay is extremely intelligent, another trait it shares with corvids. It is a bird that has been able to adapt to human life and succeed. Proof of this can be seen in suburbia and even our own campus. In a world dominated by mammals, it is noteworthy that such birds have carved out a niche in order to live in a symbiotic relationship with humans, even if they do have an annoying call.

Udvardy, Miklos D. F. National Audubon Society Field Guide to North American Birds. 1994 Alfred A Knopf, Inc.

Nehls, Harry B. Familiar Birds of the North West. 1983 Audubon Society of Portland.

Western Scrub Jay. http://eco.bio.lmu.edu/socal_nat_hist/birds/orders/pass/jay_sc.htm

Western Scrub-Jay. http://birds.cornell.edu/BOW/WSCJAY/