American Herring Gull L. (a.) smithsonianus.
December 19th 2003 Choshi Chiba Japan
A female-type, 'gentle' smithsonianus. The greater coverts are not that completely dark, but the smooth dark brown overall appearance seems suitable for smithsonianus. This bird apparently resembled Thayer's Gull, except its strongly blackish primaries, dark tertials, and palish leg color.
A male type on the same day.
Vega Gulls on the same day