Nice northern Chiffchaff

I did a quick trip down to Monk Haven to see if the Firecrest was still about and I coulnd find anything but on the filter beds in the Sewerage works there were at least seven Chiffchaffs feeding along with Grey Wags, Pied Wags, Chaffinch, Dunnock and Blackbird.
One of the Chiffs is a very pale northern type worth a good look with a scope to try and pick up the details - look at the Bird Guides links which follows.
http://www.birdguides.com/webzine/article.asp?a=1203