Mongolian Gull Larus c? mongolicus
March 19th 2004 Choshi Chiba Jpaan
The ground color of scapulars is white, plus some pale warm buff pigmentations. Vega Gulls tend to have darker greyish tone on it.
Note the heavily worn tertials. Vega Gulls can often show pretty fresh tertials even in March.
Note the barred axillaries
2 Vega Gulls on the same date for comparison