Subject: western gulls upriver
Date: Dec 5 14:17:08 1994
From: Dennis Paulson - dpaulson at ups.edu


Andy, I was amazed to see three of what I considered entirely typical
western gulls at McNary Dam, plus there were several obvious G-w X W
intergrades there; and I had just recently questioned Ken Knittle on
records of the species in Benton County! As for why, my guess is that
following a big river like the Columbia upstream is a perfectly natural
thing for a western gull to do, when (a) food comes drifting down the
river, and (b) other gulls go flying up it. Lots of glaucous-wings move up
the river, apparently, and at least a few of the large population of
westerns at its mouth must do likewise. There are plenty of westerns in the
flocks of smelt-snatching gulls on the Lower Columbia in early spring,
likewise.

There isn't any other place for this to happen--a really large river
draining to the outer coast where western gulls are common--except possibly
the Sacramento River system in California, and it's got San Francisco Bay
in the way to confuse the issue (it probably isn't as large at its mouth
either).

Speaking of gulls at McNary Dam, I am sooooooo glad that I decided to play
hooky on Thursday! It's nice to win one.....

Dennis Paulson phone: (206) 756-3798
Slater Museum of Natural History fax: (206) 756-3352
University of Puget Sound e-mail: dpaulson at ups.edu
Tacoma, WA 98416