1st winter/summer Vega Gull L.vegae

Mach 11th 2002 Choshi Chiba Japan
The scapulars and flank seem to be second generation.
The head is getting whitish, and second-generation scapulars are visible. But the other parts remain almost juvenile plumage. The uniform brown belly unlike Mongolian Gull is quite typical. The width of the tail band is intermediate between Mongolian Gull and American Herring Gull.
Almost juvenile plumage, except for some upper scapulars.

March 13th 2002 
Tamagawa-river Kawasaki Kanagawa Japan 
It looks somewhat whitish in this photo (because of dark water?). But in the field, it was obviously normal Vega Gull that shows  brownish, uniform appearance unlike Mongolian Gull.