More on Chiffchaffs

At least one classic tristis race Chiffchaff is among the birds ranging along the tidal wrack between Neston Old Quay and Denhall Lane (See December 13th post) This has been since heard to call by several observers, and appears to fulfil all the current  identification requirements. There is another bird also thought likely to be one. However not all birds appearing to be tristis are. Both the following 2 pictures are of the same individual photographed at Denhall Lane. In the first shot it appears to have many classic tristis features, no obvious olive or yellow tones, buff wash on super and cheeks e.t.c. On the second heavily cropped shot, however, an olive yellow tinge can be seen on the forehead and start of the super. Furthermore there are rivulets of olive green feathering visible on the mantle.This bird called once, a very untristis like hueet, higher pitched than the usual call of collybita. So what race is this? It is certainly not a definite tristis.We would have once lobbed this in as an abietinus which where we put all the indeterminate birds. Current thinking is that this race is much rarer than tristis, in the U.K, however, and it may no longer be used as a label for all the indeterminate birds. Could it be form the West Siberian form fulvescens? This race is supposed to have traces of yellow. Could it just be a very pale collybita? I have absolutely no idea what race this bird is and birds like this are no doubt the reason Siberian Chiffchaffs, distinctive if all features can be seen, are having such a hard time getting split, if at all they should be! These fascinating little headscratchers certainly need to be identified with caution!