Not Quite Oxon (Streatley)

tristis type Chiffchaff at Streatley

If the tristis Chiffchaff at Abingdon is proving tricky to view through the fence there are two other, much more showy non collybita birds at Streatley Treatment Works (100m north of the church). Unfortunately this is about 150yds into Berkshire. Yesterday there were 5 Chiffchaffs present, 3 nominate (one tailess) and the two tristis. To me they tick all the boxes, particularly one of them, with the other towards the striking abietinus end of the range but still ok I think. The best thing, however, was at one point when they were together one or both (it was difficult to tell) had a period of repeated calling - perfect tristis! Their appearance metamorphosed greatly depending on the light. The pics above are of the same abietinus like bird.