Tristis

This interesting Chiffchaff was jumping around a bush by my car at the end of Meadow Lane, Bedford today.  Its call instantly drew my attention to it - as it sounded a bit plain and monosyllabic.  I got a pretty good view of it and it was fairly brown with the only green on the plumage being on the wings and on its tail sides.  It had a scruffy cheek with a few feathers out of place but it did have a really nice flaring supercillium.  The underparts were dull cream getting slightly brighter towards the centre.  The upperparts were grey-brown - all in all it looks pretty good for tristis.  Have a listen to the call (below) - mostly pretty even, but one or two calls were pushing towards the 'seoo' end of things.  I wonder if its in the variation of tristis?  More research needed but it does look good.
Chiffchaff at Meadow Lane 8th Jan 2012 by Steve Blain