1st winter ''barrovianus'' Gloucous Gull
　Larus hyperboreus barrovianus ?

Note the same bill size as background Slaty-backed Gull.

Compare

Juv Iceland Gull.With 1Glaucous Gull,3Slaty-backed Gulls,1Kamchatka Gull.
2004/12/11 Mukawa Hokkaido. →More photos

1w nomal-type Glaucous Gull.

From Mukawa Hokkaido Japan. April 5.