Well, I'm glad I didn't get "flamed" for my comments on scrub-jays as
terrorists. I think they're neat birds, too, and I was tickled to see
one flying across I-5 at the Tacoma Dome the other day. I'm usually
all for letting nature take its course. and we'll have the
opportunity to do so as this species colonizes more and more of
tweeterland. Forty years ago, the farthest north that scrub-jays were
known to occur as residents in the state was at Woodland, and it has
been interesting seeing their spread northward and eastward, first as
isolated individuals, then as populations.

I don't think oaks are at all a prerequisite for the presence of
Western Scrub-Jays. The jays are opportunistic omnivores and will be
successful wherever there are people with bird feeders, as in many
cities in California where you scarcely see an oak. They may thrive
even in areas without bird feeders, although then perhaps the oaks
are more important, as can be seen where they are commonly associated
with oaks in parts of southwest Washington. They have moved up the
Columbia River to the oaks of Klickitat County, and I suspect they
will fill that environment and slowly move farther into eastern WA,
moving from one cluster of bird feeders to another. They are not as
mobile as crows, so they probably won't colonize the Columbia Basin
as rapidly, if at all.

Long before global warming came under discussion, many bird species
had been extending their resident or wintering distribution farther
north because of all the changes we have made in the landscape,
especially providing food at bird feeders. Perhaps global warming is
accelerating this process, but it would be most interesting to see
how much ranges have extended northward in birds that are not at all
dependent on human provisions or habitats (e.g., reservoirs where
there were only rivers, orchards where there was only sagebrush)
during the winter.

When I go on winter field trips in the interior, where it is truly
wintry, it dawns on me how few birds I find that are totally
independent of human endeavors. Would that Rough-legged Hawk have
been there if the sagebrush hadn't been replaced by farmland? Is that
flock of redpolls feeding on the seeds of a native herb or a weedy
one? Are the Steller's Jays more likely to be out in pristine conifer
forest or hanging around bird feeders in the small towns? Etc.
-----
Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net



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