ID of large gull in South London, UK (1 Viewer)

[Jonno52]

Hello all, this is my first proper post here since registering ages ago. I'd be very grateful for thoughts on the ID of this gull. The 2 photos were taken from the window of my London flat on 17 April (I used to be a fairly active if not very competent birder, but am now flatbound). From memory the light was cloudy bright.

I only saw the bird for 4 or 5 seconds before it disappeared behind trees, just time to focus manually with my Canon 100-400mm Mk1 & grab a couple of shots. I first took it to be a Herring Gull, but later the wingtip pattern with little white and apparently just a single mirror, on primary 1, and rather squared-off black wedges, brought to mind Yellow-legged Gull. The colour of the upperparts seemed a little dark for Herring, but it's difficult to assess plumage tones on a lone bird, nor are the photos good enough to get a clear idea of orbital ring colour or extent of red on the bill.

I now think it was probably Herring after all, but am still a bit puzzled by the wingtip pattern.

I shoot in RAW & jpeg, and did some basic processing in Digital Photo Professional 4; if it would help I could provide a jpeg taken from the RAW with no processing. Thanks in advance!

 

[Laruslister]

If it was a Yellow-legged Gull the black tips would extend to P5 and be a complete and equal width w of black.I know this as it is the only way to get them accepted by Scottish Birds Record Committee.You can have all the other features,but without this theywon't accept one.

 

[lou salomon]

it's a herring gull. as said, no p5 mark and black even more extended on bases to p8 and p9 (with p10 being the outermost primary, in gulls and raptors you count from inners to outers :news

 

[Jonno52]

Thanks very much. Going back to the reference books, I see exactly what you mean: my assessment of the wingtip pattern was pretty superficial, and I've at least learned something from this. It would have been nice if it had been a Yellow-legged, but it's a species I've seen a couple of times (bona fide well-watched birds) so not too much depended on this.

Again, I'm grateful for your help and wish you good birding.

John

 

[Jonno52]

it's a herring gull. as said, no p5 mark and black even more extended on bases to p8 and p9 (with p10 being the outermost primary, in gulls and raptors you count from inners to outers :news

Thanks, I appreciate your reply and happily accept that the bird was a Herring Gull. Just on the question of how the primaries are numbered in gulls, looking at Peter Grant's Gulls, he does number them from outermost (P1) to innermost (P10). Maybe conventions have changed! I'll look into that further.

 

[Nutcracker]

Just on the question of how the primaries are numbered in gulls, looking at Peter Grant's Gulls, he does number them from outermost (P1) to innermost (P10). Maybe conventions have changed! I'll look into that further.

Yes, very regrettably, they have changed in some quarters. A universal return to Peter Grant's sensible numbering would be highly welcome, though :t:

 

[Jonno52]

Yes, very regrettably, they have changed in some quarters. A universal return to Peter Grant's sensible numbering would be highly welcome, though :t:

Thanks for the information, will bear this in mind. Gull ID seemed to have enough "pitfalls for the unwary" already, without potential misunderstandings over terminology!

 

[Jonno52]

I'd just like to add that if I'd had the current (2009) edition of Collins Bird Guide, instead of the original 1999 edition, I would never have suggested this was a Yellow-legged Gull :C. The 1999 edition wasn't the only reference source I'd looked at, but it played a part, and the 2009, which I now have (superb book) is much clearer about the wingtip pattern. It goes into more detail about p5, numbers the primaries using the convention described above by Lou, and shows the upperparts colour more accurately. I'll try and be more sure of my facts next time.