The positive identification of siberian chiffchaff (trisits) may be fraught with difficulty relying as it does on the effect of different qualities of light on gradations of hues in the mantle etc but with up to five in the county it’s certainly a good time to check them out.
The two most popular birds are at Dorney Common just on the Berks/Bucks border. These have been given the seal of approval of the county recorder
You can park either on the common, near the east entrance cattle grid, in Eton Wick or at the Jubilee river car park
The birds have been seen in the “reed beds” half the way along to the entrance to the river (do go and have a look along the river for a mass of ducks and water rail. A special treat at the moment are a group of goosander (a mega for the site)
If you prefer the north of the county there are two at Streatley sewage farm. These have been OK’d by the Oxon county recorder (click here for Oxon Bird Log – Feb 16th entry)
Clicking here links to an OS image with an arrow pointing at the place the birds have been seen (though they can disappear at times)
This link takes you to a street view of the area south of the sewage farm. I’ve seen the birds in almost all the trees/hedges you can see if you move the view through 360 degrees. The hedge at “NW” has been severely pruned and you can now see through to the clinker beds where they can also be seen
BTW the “possible” fifth is at Sandhurst STW. A regualr site for “grey” chiffchaffs & the only site in the county to have a bird accepted by the BBRC (Dec 2007- March 2008).
There are very limited parking options here. You can park in Sandhurst high street and walk …
Clicking here links to an OS image with an arrow pointing at the place the bird have been seen
This is the 2008 tristis (BBRC accepted) http://www.birdsofberkshire.co.uk/Tristis.htm
The plumage of tristis, as described by Svensson (1992)
1 It lacks yellow entirely away from the underwing coverts, the axillaries and the marginal coverts near the bend of the wing, and
2 lacks olive on the crown and mantle.
3 The upperparts are grey-brown to drab-brown while
4 the underparts are off-white, with a
5 rich buff suffusion of variable extent on the breast and flanks.
6 Rich buff also infuses the supercilium and the ear-coverts, where it can assume a rusty buff hue.
7 The scapulars, lower back and rump show limited olive streaking, while
8 the remiges and rectrices are edged with olive.
The bare parts are somewhat less consistent in appearance but most individuals have
9 a relatively slight bill which is predominantly black while
10 the legs and upper surface of the feet are also quite intensely black