Apart from the bill, which should be darker, deeper and shorter, the underwing of first winter Saunders' (saundersi) usually has a more contrasting black wedge on the primaries.
Mike Turnbull. Author: ckacheung Time: 14/12/2008 20:02
it's seemed to be the Black Head Seagull Author: hiddenplace Time: 15/12/2008 16:34
Thanks for the comments. I zoom in the picture and saw it has some red on the bill. I corrected the title to Black-headed Gull.
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