One more response on the gull ID question, this one about plumages.

A gull's first post-downy plumage is JUVENAL. Most of the gulls we see
during summer and early fall that hatched this year are in that plumage
(juveniles). During the bird's first autumn, many new feathers grow in and
produce a FIRST BASIC (or FIRST WINTER) plumage, which may be almost
identical (large gulls) or rather different (small gulls) from the juvenal.
In a Ring-billed Gull, the brown edges on the feathers of the upperparts
are mostly lost, producing a smooth gray mantle. The following spring,
more feathers are replaced, and by April the bird is in FIRST ALTERNATE (or
FIRST SUMMER) plumage. Thus the bird bears its "first summer" plumage
throughout its *second* summer of life. In a 4-year gull, that would then
be followed by SECOND BASIC (through the winter), SECOND ALTERNATE (through
the bird's *third* summer), THIRD BASIC, THIRD ALTERNATE, and finally
DEFINITIVE BASIC, or just BASIC, followed each year by DEFINITIVE
ALTERNATE, or just ALTERNATE.

Many birders describing plumages use "winter" and "summer" rather than
"basic" and "alternate," and that's fine.

Dennis Paulson, Director 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