Adult summer 
Ring-billed Gull  Larus delawarensis
March 26th 2004 Choshi Chiba Japan

The usual individual. It turned into breeding plumage earlier than Kamchatka Gulls, same as last spring.

Note that 2 Kamchatka Gulls in the background are winter plumage.

Click here to see Kamchatka Gulls on the same date for comparison