Durham Bird Club's Castle Lake Nature Reserve

Saturday, 24 September 2011

YLG Update

Further to my sighting on 13th September of a possible Yellow-legged Gull on Castle Lake, Stephen Buckle has kindly sent me an e-mail concerning an interesting bird he saw there on 30th August. (Apologies to Stephen for not posting this earlier).

Stephen describes the bird as follows;

Bird is a Herring Gull type which I aged as (moulting into?) 3rd winter as it had some pale faded brown on the upper row of coverts (not clearly visible in the photos).  My attention was drawn to it because it had much darker shade of grey to the back than argenteus Herring Gull, in fact side-by-side with adult Common Gulls you could see it had a slightly darker shade than them.  It was however (in my view) nowhere near dark enough to be an LBBG.  The bird also seemed to have a lot of red on the distal part of the bill.

These features got me excited about the possibility of Yellow-legged Gull but when we (myself and a friend I was with) got a clear view of the legs they were pale pinkish i.e. looked like those of a Herring Gull.  I said to my friend that it could not be a YLG, but could be a Scandinavian Herring Gull.

On the standing bird, the wing tips looked completely back with no white tips to the primaries.  I didn't get a good view of the spread wing, partly because I wasn't sure how helpful this would be on an immature / moulting bird, but probably also due to lack of confidence that I'd be sure of what I was seeing during brief flaps.  In hindsight I probably should have tried to get a photo or at least a good view of the spread wing.

It certainly appears that this Gull is a strong candidate for Scandinavian Herring Gull despite the early date and inland location.
Many thanks again to Stephen for the photo's and description.

1 comment:

  1. Hi Neil,

    Interesting. I have seen argentatus herring gulls with a yellow tinge to the legs, its quite worrying as I have been sent pics of a Herring Gull that basically had pure yellow legs.