A discussion of this now subspecies recently happened in Oregon.
I'm sending some of my comments in that discussion to Tweeters in reference
to the recent Glaucous/Iceland posts.

I'm always happy that people are still looking for Kumlein's Gull, nowadays
Iceland (Kumlein's) Gull, my favorite gull.
Here is what to look for.
http://www2.rdrop.com/users/green/icgu/ICGU.html
http://www2.rdrop.com/users/green/icgu/ICGU2.html
<http://www2.rdrop.com/users/green/icgu/ICGU.html>

Bob OBrien Carver OR

PS There are 6 or 7 species present here, but you won't have any trouble
finding Kumlein's. which make up about 90% of the Gulls in these photos.
Note that Adult Iceland (Kumlien's) Gull can look somewhat like Iceland
(Thayer's) Gull with dark-marked primaries,
but at least 50% have all white*-tipped* primaries, visible in flight,
while in adult Glaucous the entire primaries are white.
This can be hard to tell when the wings are folded so flight photos really
help.
And I agree that a white iris is a good mark for either, but it is not
definitive.
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