Siberian Chiffchaff Phylloscopus (collybita) tristis (including 'fulvescens')
Portland, Dorset, UK, April 2008. Photo Gabriel Jamie.
In heavy moult (typically late date for tristis). Same individual as in November but note apparently different hue of upperparts, a result of pre-breeding moult, which produces a characteristically dishevelled appearance as well as colour loss. (As well as moult of body feathers, inner tertials and central tail-feathers have also been dropped). The very green colour of surrounding vegetation can also affect camera processing.