Friday, 5 December 2014

Phylloscopus collybita tristis

It's difficult thinking up new titles for the same old dross.....

A good fall of thick wet snow came today and despite temperatures on the red side of the line it has settled over the whole of Oslo giving us a real wintery feeling.

As my day settled into its usual rhythm I reflected on how cr*p this winter has been so far. All of the nomadic winter species are either absent or are present in exceptionally low numbers: where are the waxwings, the redpolls or the crossbills not to mention rarer visitors like grosbeaks, owls or white-winged gulls. Therefore I am forced into giving more attention to a chiffchaff than it really deserves even if it is a tristis and even if it is an exceptionally late record for this neck of the woods.

It was quite cool to see the bird in the snow today and it was still quite active. I saw it preening for a minute or so but the pictures I took show that its plumage is not in the best of condition although it did seem sprightly enough and seemed to find something to eat (or at least swallow) on a couple of occasions. Today it was completely silent in the half hour I was on site. Let’s hope it survives!

I was able to undertake a virtual in-hand examination of the bird today without actually having to molest it. The pictures I took allow an interpretation of the wing formula. The second primary (P2) of a tristis is usually shorter than on the other two northern subspecies (collybita and abietinus) with it often being only as long as P9 whereas it can be as long as P7 or even P6 on the other subspecies. The pictures show it to be as long as P9.
a virtual in-hand shot. P2 finishes under the longer P3 (which is itself under P4 which is the longest feather). The length of P2 can be seen to be as long as P9/10 and much shorter than P7
this picture shows the same. P2 is only as long as P9. (the 10 dots are on each primary tip with the ting left hand feather being P1)

there was a lot of preening going on

not quite sure what the black spot is. possibly a tick?

there has to be a video, doesn't there? Where this video differs from the others is that you DON'T just hear the bird whilst squinting at a fuzzy picture but this time you do SEE the bird and for a second or two actually in focus and you don't hear it at all. Enjoy!

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