Have started to use Peter Harrison's "Field Guide to Seabirds of the World" in
paperback--don't know if it would be of any help. The only Laughing Gulls
I've ever seen were in the east but, of course, that's no help at all. Wish I
knew more. Maybe try his hardcover book which shows much greater detail.
Good luck--I mean: how many of us REALLY do gulls!

Murray Hansen
Graham, WA
MurrayH at aol.com