This is a Heuglin's Gull, Andrew. The almost complete lack of pale inner primaries favours this species more than Slaty-backed, in actual fact. Slaty-backed usually has paler inner primaries, if not strikingly so. Further, the tail band is rather too narrow for Slaty-backed. In addition, the ground colour of the head and underparts is rather too clean and white.
What is interesting about this bird is that it appears not to have moulted any greater coverts.
Second-winters of many large gull species, including Slaty-backed, have pale eyes and a rather more obvious pale tip to the bill.
GeoffC
[ Last edited by cgeoff at 31/03/2010 16:37 ]
