Chiffchaff, Phylloscopus collybita

Chiffchaff, 12/31/09, Clissold Park, London, UK
The Chiffchaff is an old world warbler, common in London parks in summer, but, so I was told, it was noteworthy that I was able to photograph this one on the last day of 2009 in the vegetation lining one of the ponds in Clissold Park.