I believe this is an "Kumlien's" Iceland Gull. Though is does have the pink-based bill like a juvi Glaucous, Glaucous should have a sharper border between pink and black, brighter pink on the bill, and a thicker bill in general. Glaucous also has pure white wingtips, rather than the smudgy gray like this bird has. Finally, a Glaucous's head would be bigger and blockier, with small and beady eyes ("piggy eyes" as I call them....".
