Chris Hill's comments were interesting about Ross' Gull underwing color,
and I agree with him that it's a great field mark (how about a Little and a
Ross' flying around together for comparison? I saw that at Churchill,
Manitoba, within a half-hour a Sabine's Gull flew by the same spot, and
there were Bonaparte's in the area; I was hopping up & down by that time).

One comment about color change, though. Feathers fade a lot, probably
mostly from the UV component of sunlight, and, because of this, I kind of
doubt that underwing coverts would fade very much. You'll see this if you
look at first-year gulls in late spring, before they molt. In some of them,
at least, the upperparts are extremely faded, but the underparts don't look
much different from their appearance in fall. This makes for some
funny-looking gulls.

Hope everyone has a weekend full of avian delights.

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