A reasonably interesting day in north Bucks.
At Manor Farm this morning (which btw is looking very suitable for waders, a ray of hope amongst the degredation of the traditional, once reliable sites), 1 Dunlin, 2 Green Sand, 2 Shelduck, 12 Wigeon and best of all a vocal Tree Sparrow in the dead trees on the south shore. Maybe it was looking for prospective nest sites.
In the Ravenstone Valley, little of note other than 32 Golden Plover and 9 Barnacle Geese.
At Backwood, just 1 Lesser Redpoll, the finch flock presumably either elsewhere or moved on.
At Willen in the evening, 18 Goldeneye and 1 Redshank on the north lake, plus a rather elusive but interesting Chiffchaff. Calling frequently as it flitted about amongst lakeside brambles near the weir, not once did it utter the standard "hweet" call of a collybita, but rather a piercing, slightly slurred call with a downward inflection. Nothing like the rather plaintive piping of a tristis, but abietinus did cross my mind.
After a bit of research at home, I did find an exact match - http://www.xeno-canto.org/europe/recording.php?XC=45386
Apparently though collybita sometimes calls like this (I've never heard abietinus in the field). Plumage wise, the brief glimpses I did get were also enough to rule out tristis - not buff/brown/white enough in the relevant places, too olive-green on the wing, mantle and in the supercilium. Whether this rules out abietinus I don't know though (Rob Hill).