After failing to find any divers in Dover Harbour this morning I had a look at the roosting gulls. One white-headed, yellow-legged bird caught my eye. I thought it was a Yellow-legged as the legs are yellower than any Caspian I've seen previously, but the head looks very white for a winter michahellis. I was about 100 mtrs away and it was rather windy so apologies for picture quality.
The mantle colour was a shade or two darker than the Herring Gulls, as one would expect with michahellis.
Something disturbed the gulls and they all flew. Judging by the leg colour the bird in question is the right hand bird in near centre. Opinions appreciated.
A note from Andy Lawson, Kent's well known gull enthusiast, put the following points in favour of L. michahellis, on a quick look at the photos.
Yellow-legs (but I photographed a YL Herring at the weekend)
Square back of the head.
Darker grey upperparts (than nearby Herring Gulls).
white head (it's effectively in summer plumage).
small, white tips to primaries.