Subject: [Tweeters] RE: Seabird numbers, White-winged Scoters
Date: Jan 9 09:13:31 2006
From: Guttman,Burton - GuttmanB at evergreen.edu


The various posts about seabird numbers, including W-W Scoters, have been interesting and puzzling. I appreciate Jeff Kozma's note summarizing a serious study of the scoter situation, but please notice the inconclusive conclusion: "Population trends for scoters are uncertain but appear to be declining in some regions, while remaining stable or increasing in others. Affiliations between breeding and wintering areas are unknown, and interpretation of existing population survey data is difficult without this information. Identifying the location of breeding grounds, migration routes, wintering areas, and the timing of migration is an essential first step if we are to identify potential causes of population declines such as the effects of habitat alterations, and sources of contaminant exposure."

So an important part of the take-home lesson is, "More research is needed." Looking over various reports about alcids and others, we see some conflicting (sometimes seriously conflicting!) impressions: More here, fewer there, maybe more than previous years, maybe fewer, and so on. Or at least that's my impression of them. I wonder if any of you are in a position to evaluate these reports all together and see what conclusions, if any, can be drawn from them. The birds are able to move around quite a lot, and if observer A reports seeing few alcids (for instance) in one spot and observer B reports seeing more of them in another spot, it would be valuable for someone to put the reports together and, perhaps, conclude that the numbers appear to be stable and the observations can be accounted for my local movements. I ask because I think the results would be of real general interest, and it's the kind of project I might suggest for a student, but I don't have the time to do such an analysis myself. Any takers, or any reservations about the possibility of doing such a study?

Burt Guttman
The Evergreen State College
Olympia, WA 98505 guttmanb at evergreen.edu
Home: 7334 Holmes Island Road S. E., Olympia, 98503