Sunday, 30 October 2011

Desert Wheatear again

I went back and had another look at the bird this afternoon. There are now many more photographs available to view as well (on Orkbird).

Here's an update on my thinking re this bird.

Age: pale edges to the primary and greater coverts, to the 2aries and pale tips to the primaries lead me to a bird in its first calendar year.

Sex: this afternoon I noted a brownish tinge to the ear coverts, in all three species that would make it a female.

I made comments about the bird’s structure yesterday which I won’t repeat but they point to Desert Wheatear. Additionally, I noted today the constant tail wagging which is a feature of Desert Wheatear but I don’t know if the other two species do this to the same degree (Northern Wheatear for example does not). The bird often has a rather supine as opposed to upright posture.

The tail pattern seems to be the feature that is causing most confusion and leading to identifications other than Desert Wheatear. However, my view would be that Lee is entirely correct because:
The extent of black on the tail from the tip up towards the base is consistent with Desert Wheatear and not consistent with Red-tailed which, according to the photos I’ve looked at does not have black extending so far up the tail as the bird we have, it would be about 50% less for that species from photos. Red-rumped Wheatear would not be eliminated on this feature however (but it is eliminated on a host of other plumage features, e.g. rufous brown crown) (Mullarney et al)
Red-tailed Wheatear should have a Northern Wheatear like T of black in the tail but our bird does not have that feature. I think that T should be formed by black extending further up the two central tail feathers, 6 and 7 (I’m numbering from left to right) (Svensson). Our bird appears to have some additional black extending up the edges of tail feathers 5 and 8 in particular. Our bird also appears to have dark centres to two of the central upper tail coverts. I believe these features are combining to give an impression of a T which does not actually exist.

I do agree that this bird is unlike typical Desert Wheatears, it is rather drab and grey and is not so contrasting in its plumage but to my eye I can’t see any reason for it to be anything else. I would reiterate that I am no expert and I’m making these judgements on available reliable references and a fairly brief review of easily available photographs as well as the few hours I’ve spent in the field examining the beast.

I’ll be very happy to be proven incorrect but none of the reasons put forward to this point have convinced me to change my opinion. Convince away….

And on to other things...
Thanks to the heads up from AL I headed to Langskaill later this afternoon. First bird I saw was a Yellow- browed but that was not the quarry. The give away call could be heard softly. A Chiffchaff showed and showed, then a Goldcrest. Eventually after 15 minutes of perseverence, joy, Long-tailed Tit!

Then a nip to Scapa and two Little Auks in the fading light; lots of gulls there as well.

Back at the ranch today there were still many Blackbirds, 30 or so; at least two Robins, five Reed Buntings and a few Brambling and Chaffinch.

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