Friday 19 September 2014

More Gulls

I was greatly relieved to find myself back in the hedge at Shawell A5 Lagoons again on Wednesday evening - no noisy bird club outings at this site.

Shortly after my arrival I found a first year Mediterranean Gull, which was happily knocking around with about 100 Black-headed Gulls on the far shore. This is the the third this year at the site and only the fifth one I've seen at the site since my regular visits began in 2012.

First-winter Mediterranean Gull

After the Med Gull, I noticed a pale headed first calendar year gull hiding amongst the lesser Black-backed Gulls. Much of the time it was facing away from me, so it was difficult to work it out structurally. Eventually it spun around and gave me a side view. As well as its pale head, I could see that it had replaced most of its scapular and mantle feathers. Its saddle was obviously greyish and small anchor markings could be seen on many of the feathers. It was noticeably long winged and its general profile looked good for Caspian Gull. Many of these features are very subtle and not as obvious as a first-winter Caspian Gull will be in a month or two.

1CY Caspian Gull (note the elongated appearance)

The greater coverts have obvious 'notches', which posed me a few questions. However, many of the Caspian Gulls found HERE show similar 'notches' - these were photographed in the core breeding areas for this species. Note the long low profile typical of Caspian Gull. I watched it for quite a while before it raised it wings and when it did I could see that it underwings were very pale and that its tail had a thick black band which contrasted with a white rump.

1CY Caspian Gull (the black tail band is just visible under the wings)
1CY Caspian Gull
1CY Caspian Gull
1CY Caspian Gull (note the slopping forehead)

Identification of gulls like this one is never straightforward, as it is important to discount similar species. Structurally it is distinct from Lesser Black-backed and Herring Gulls. That said there is a great deal of variation and so a careful approach is required. Unfortunately the gulls at Shawell are generally a bit distant for photography - these are all screen grabs from video. 

As always I'll be happy to hear any opinions on its ID.

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