Hi Steven,

Thanks for your post. I am most definitely not an expert on immature gulls.
But I always thought that a very large, very pale gull with white primaries
and a cleanly demarcated bicolored bill was strongly indicative of Glaucous
Gull.

Could you elaborate more on your last statement, the "tale of two bills" so
to speak? The bird at Dungeness had a large bill that was pale pink for the
first 60-70% of its length, with the remainder being black. The pink/black
line was very clean and very sharp, and more or less vertical -- very much
like the few other 1st and 2nd year Glaucous Gulls I've seen around WA and
BC.

The only reference to a Glaucous-winged "bicolored" bill [in my admittedly
small library] in a young bird (1st or 2nd year) is in Sibley. His second
year bird has something approaching the same two-toned pattern, but it is
more smudgy and blended looking, without the sharp vertical demarcation.
The 3rd year bird next to it has a cleaner looking tip, but the basal part
is yellow (and of course the rest of the gull is all wrong for the Dungeness
bird). My other books indicate that young GW's should have dark (or nearly
dark) bills.

Can you say a little more about how the two species' bicolored bills are
alike and different, and perhaps point me to a reference? I have to say, I
was a little surprised to come across a Glaucous Gull in early August.


Learning something new every day,


Hans


Hans de Grys
Bothell, WA
degrys at verizon.net