Hello, tweets.

Joel Elliott, a colleague of mine at the U. of Puget Sound, is studying the effects of Glaucous-winged Gull predation on sea stars in our waters. It's all he can do to conduct his research, along with students, in the general Tacoma area, and he's trying to learn more about such predation elsewhere in the state, anywhere on marine waters, as there seems to be some interesting variation and definitely some interesting natural history.

Is there anyone out there who has information on, or would be willing to spend some time observing, any of the following?

1) Gull density in the intertidal.
Joel is quite interested in knowing where gulls spend a lot of time foraging in the intertidal, so he can compare, among other things, rocky and sandy habitats. Any sort of quantification is of interest, even if as simple as "50 gulls feeding along a quarter-mile of sandy shore" or something like that. They have to be actively foraging, not roosting. Locality is obviously important, also date (month is good enough). Time of day isn't important, as we know they only do this at low tide.

2) Gull diet in the intertidal.
Quantified accounts are obviously of much greater value than single anecdotes, but I would be happy to gather even single anecdotes of actual food items that you've seen going down the gullet of a Glaucous-winged Gull (or any other large gull, but not smaller ones), where it was, the date or month if you can remember (there are seasonal differences), and some indication of the habitat, unless it's a well-known site.

3) Sea star density.
This is one that I assume few birders pay much attention to, but it's surprisingly variable. Gulls apparently eat small sea stars (total diameter around 8 cm or less) freely, but in some areas at least, the smaller ones stay hidden during the daytime, presumably a response to the predation pressure. At some times and places they are exposed, and Joel is trying to understand why. Also, the blood star (Henricia leviuscula), bright red with slender arms, is apparently not eaten by gulls, so any observation of a gull dealing with one of these beauties is of interest.

I guess that's it. If anyone has info or is interested in gathering info, please let me know, and thanks.

Dennis
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Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net



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