Birds are lazy, and quickly adapt to human made
habitats if those spots have more food and cover. In
AZ, sewage treatment plants are now prime birding
spots, replacing part of the lost riparian habitats.
In winter, we've often noticed that we'd be better
off watching our feeders than tromping around looking
for non-welfare birds. In WA, it looks like
blackberry brambles are prime winter food and cover.
These are often on vacant lots or other disturbed
habitats.

The old theory was that urban habitats were wildlife
sinks -- they suck in birds temporarily, but the
birds didn't survive. I don't think that theory
actually works, any more, especially in older suburbs
where there is lots of cover. I've watched several
pair of Cooper's Hawks sucessfully breed repeatedly
near my former home in Palo Alto and my new home in
Tucson.

Sure wish some young grad. student did some actual
research on this.

Dick
--- "Guttman,Burton" <GuttmanB at evergreen.edu> wrote:

> It has been said that birds are where you find them,
> but anyone with an ecological view of nature doesn't
> find that old saw very enlightening. I want to
> raise some questions about where birds live and
> congregate, and why. Dave Milne and I did part of
> the west side of Olympia yesterday for the local
> CBC. We drove about 25 miles, mostly very slowly,
> edging up to interesting-looking yards, lots, and
> woodlands, where we looked and listened; my ears are
> lousy, but Dave's are good. We walked several
> miles, often through such woodlands or patches of
> parks or lonely lanes. The weather was pretty good,
> until late in the day.
>
> We generally found these natural areas quite empty
> of birds. To us, they looked like great habitat,
> and we kept saying to each other that if we were
> little birds, we would love to live there. But then
> we pulled up next to a lousy little vacant lot on
> one of the busiest west-side streets, across the
> street from a middle school, and it was swarming
> with birds! There were at least 15 juncos, several
> chickadees, both species of kinglet, and at least
> three Townsend's Warblers. This was a lot where a
> lot of cut-off tree limbs had been dumped, along
> with bits of human-made trash, and it was sandwiched
> between two relatively crummy houses. There was a
> lot of invasive blackberry in the underbrush.
> Similarly, we walked to a patch of junk shrub, also
> largely blackberry, near the waterfront and found it
> swarming with House Finches, with some sparrows and
> others.
>
> Just what are the factors that make birds prefer one
> habitat over another, especially during the
> off-breeding season? Blackberry and other plants
> that we consider junk may have been one factor in
> what we observed, but I doubt that that's the only
> factor. I'd be really interested to see other
> people's observations relevant to the question and
> to hear some ideas about the factors that determine
> bird distribution.
>
> Burt Guttman
> The Evergreen State College
> Olympia, WA 98505 guttmanb at evergreen.edu
> <mailto:guttmanb at evergreen.edu>
> Home: 7334 Holmes Island Road S. E., Olympia, 98503
>
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>


Richard Carlson
Full-time Birder, Biker and Rotarian
Part-time Economist
Tucson, AZ, Lake Tahoe, CA, & Kirkland, WA
rccarl at pacbell.net
Tucson 520-760-4935
Tahoe 530-581-0624
Kirkland 425-828-3819
Cell 650-280-2965