bird 8 - Gull spec., adult, Choshi, Japan, 15 March 2012.
Perhaps the most controversial bird in this series.
Strong sunlight makes the upperparts look particularly pale here,
and the bird is standing more in profile than all other gulls
around it, making assessment of mantle colour rather unreliable.
Head is only lightly streaked, perhaps giving more of an impression
of Vega Gull than Slaty-backed. Note very broad white collar on
upper mantle though (usually a bit less wide in Vega Gull) and
pale underside of wingtip.