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Pui O Autumn 2010

Oh dear. I seem to have been designated as a raptor expert. Serves me right for weighing in on the previous accipiters (many of my previous posts on Accipiters have been because I'm trying to work out for myself which features are useful). This is just setting me up for an embarrassing mistake at some point. Ok, here goes...

I think the wing structure on this bird is not right for a Eurasian. The outer wing is not as long as I would expect (Eurasian typically has a fairly obvious 'hand'). If you check the relative lengths of the primary tips, there is no obvious gap between the longer outer primaries and the shorter inner primaries. Compare the wing structure of Eurasian (note the large difference in length between Primary 6 and Primary 7):
http://orientalbirdimages.org/se ... Family_ID=&p=17
and Besra (note that Primary 6 is not much longer than Primary 7):
http://orientalbirdimages.org/se ... Family_ID=&p=12
and Japanese (long gap between Primary 5 and Primary 6):
http://orientalbirdimages.org/se ... _ID=&pagesize=1)
Overall, this suggests that the wing is fairly rounded on the Pui O bird. It also (to me) seems bulging on the secondaries (first and last pictures especially). This would fit better for Besra than the other two species.
I don't think the tail length is a problem for Besra, which is relatively long-tailed. It does seem to be too long-tailed for Japanese, though.
Among other features, the barring on the tail seems to be very broad (compare to the links given, especially for Eurasian), the underparts are fairly heavily barred and the bird seems to have a 'hooded' appearance, which I associate more with Besra/Japanese than Eurasian (which is paler-cheeked, and thus more 'capped').

So overall, I think this appears to be a Besra, based on a relatively rounded wing, longish tail and certain plumage features. But I'm very open for more discussion about ID - like I said, I'm still learning all this for myself!

[ Last edited by ajohn at 11/10/2010 16:32 ]

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Can I please ask anyone visiting Pui O to keep a look out for any dumping and report it. It would be a real shame if this site went the way of Kam Tin - which now has virtually no grassland left.

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This White Wagtail is ocularis. Note the black eye-stripe

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