Western Scrub-Jay, Jackson Bottom Wetlands, Hillsboro, Oregon on 8 December 2007 by Greg Gillson.
In the 1940's Western Scrub-Jays reached the northern limit of their breeding range at Portland, Oregon. Since then they have increased in numbers and, especially since the 1990's, expanded into southern and northern Oregon coastal communities, Central Oregon, and even into the Puget Trough region of western Washington to become more and more expected in communities in the Seattle region.
Many casual birders and the general public call this bird "Blue Jay." However, the Blue Jay is a crested jay found east of the Rocky Mountains, rarely in the Pacific NW, except for eastern Idaho and nearby areas, especially in winter.
The Western Scrub-Jay is crestless. It ranges from western Washington and Oregon, eastward across southern Oregon to southern Idaho southward to western Colorado, and then from these areas south to Baja California, western Texas, and well into Mexico.
A few years ago, the former "Scrub Jay" was split into three species, the presently-discussed Western Scrub-Jay, the Florida Scrub-Jay, and the Island Scrub-Jay of Santa Cruz Island off the coast of southern California. Really, though, there are several additional distinctive populations and more splits are possible in the future. For instance, the bold and aggressive Western Scrub-Jay in the oak groves and towns of the West Coast from San Diego to Seattle are the "California" form of Western Scrub-Jay. In the Great Basin junipers resides the "Woodhouse's" form of Western Scrub-Jay. It is duller of plumage and is very shy and secretive!
Attracting these birds to your backyard is not a problem. If you have a feeder they will be present. In fact, their aggressive nature toward other birds may make you wish you could keep them away! In spring and summer they eat more insects and berries than seeds. However, in the fall they may come to "steal" sunflower seeds and peanuts, repeatedly gulping down large quantities in short order, then flying off to regurgitate and bury them in a winter cache.