Coldwaltham
‘eastern’ Common Chiffchaff Phylloscopus
collybita
Despite the dangers of commenting
upon digital photographs as they all too easily convey an inaccurate
impression, in sharing some images of this interesting bird with two correspondents,
whilst they suspect that it may not be a ‘classic tristis’ they do
consider that it appears to fall within the plumage limits of tristis/fulvescens
as a whole, and is not a ‘grey and white’ Chiffchaff as defined in ‘Siberian
Chiffchaff revisited’ (Dean and Svensson, British Birds 98: 396-410).
Full details will be submitted to BBRC as they are seeking submissions of all
Chiffchaffs in 2008 considered to meet, or are close to meeting, the
identification criteria for tristis. See http://www.birdguides.com/webzine/article.asp?a=1203
I wish to thank both Roger Riddington and Alan
Dean for being prepared to comment so helpfully and thoroughly on the images
they were sent.
David Cooper
A recording which includes the call
of this bird can be heard by clicking the link Here
Best played back at high volume. On playback of the cut the Coldwaltham ‘eastern’
Common Chiffchaff calls are most-easily audible at 17 seconds, 27 seconds,
28.5 seconds, 33 seconds, 36 seconds and 53.5 seconds.
For comparison some images taken
from the same site of Phylloscopus collybita
collybita can be seen Here
A further image supplied by John F Cooper taken in dull flat lighting unlike the above that were taken in brighter conditions
