cthomas

22/3/2009
Mai Po 米埔

cgeoff

Quite tricky with such distant shots as this. However, I think this is probably Slaty-backed Gull. The tertials and primaries in the closed wing appear rather dark, and overall the bird is a little darker than I would expect 1y Glaucous-winged to be, esp the tail.

Geoff

lpaul

Do you have any pictures which show the under wing, especially the underside of the primaries.  These are strikingly pale on 1st winter G-w Gull.  I would favour G-w Gull, but without better photos it is difficult to be sure.  I think the overall uniformity of the bird (especially the lack of a pale rump/uppertail coverts) fits G-w Gull better than Slaty-backed.

[ Last edited by lpaul at 25/03/2009 11:38 ]

cthomas

Thanks for all reply!
I have took another picture today. May this one be a GW Gull?
11/4/2009
Mai Po

[ Last edited by cthomas at 11/04/2009 23:20 ]