wgeoff

Attached 7 photos and 2 enlargements of the raptor seen being harried by a Large-billed Crow on Po Toi today (Saturday 10 May).



It is about the same length as the Large-billed Crow although with larger wingspan. The head and breast are pale whitish, the belly darker, possibly rufous. The underwing is pale with dark (rufous?) carpal patches, blackish wing tips, whitish under primaries and a rufous tinge to the underwing coverts.

From the size and other features, I think this is a second year Brahminy Kite.

[ Last edited by wgeoff at 18/08/2010 17:55 ]

kmatthew

Yes, my first reaction looking at these photos is Brahminy Kite too. I have seen adults in Australia, the shape looks similar. How many records are there of Brahminy Kites in HK??

yyattung

The underwings look too pale to be a Brahminy Kite to me. I post a picture for comparison which is a immature Brahminy Kite taken in Philippine, Oct 2006.

wgeoff

Yes, I agree the underwing is much paler than the standard photos or images of immature Brahminy Kite. But the body is very different also, as the photos show.  

This bird is obviously well advanced towards an adult bird because the body plumage is almost adult. Also the underwings are starting to show a rufous colour just about visible on my photos. To quote MacKinnon Birds of China "Immature brownish all over with streaked chest, becoming greyish-white in second year and reaching full adult plumage in third year" which suggests there may be an interim phase between immature and adult. That is why I have suggested this is a second year bird. Perhaps I should call it 'sub-adult' as in this diagram from 'Birds of the Philippines', which shows a very pale underwing.



Anyway, it appears that some immature birds can have very white underwing. If you look at this website, you will see on the bottom line photos of immature Brahminy Kites which are very much paler underwing than your photo.

www.birdphotos.com.au/brahminykiteweb

The final question is - if not a Brahminy Kite, then what is it? The general plumage pattern of body and underwing is very distinctive and only seems to fit Brahminy Kite to me. Plus the size, shape and time of year are more for Brahmini Kite than other species of say Buzzard.

ajohn

To me, the bird in question looks like a typical Common Buzzard.
The dark carpal patch, which contrasts with the rest of the underwing coverts, is perhaps the most obvious feature on this bird and is typical of Common Buzzard. The dark lower belly of the Po Toi bird also fits common buzzard, and the pot-bellied structure also, to my eyes, makes it look like that species.

Brahminy Kite should show more uniform wing coverts.  They also seem to typically have dark secondaries, contrasting with a paler area on the primaries (even on the paler-winged birds in Geoff's link, the secondaries are mostly dark) - there may be some racial variation in this, but I can't find any pictures showing a pale underwing with contrasting dark carpal area (as on the Po Toi bird).

Obviously this would be a very late date for Common Buzzard - the latest recorded in the Avifauna is 21st April - but does that really make it less likely than Brahminy Kite, with 6 previous records (none since 1990)?

kmatthew

The fifth photo gave me an impression that it was a Brahminy Kite due to the paler head and breast and darker lower belly, it was the first thing which came to my head. But I do agree that the underwing is too pale after looking at different photos of Brahminy.

I guess Buzzards have such wide variety of colourations, I won't be surprise if there are some out there with dark belly, dark tail, pale underwing and a pale upper body...Though I have never seen Buzzard with colouration like this, not saying it doesn't exist, as I have seen limited amount of variations!!

The thing which bothers me now is that it's tail looks too dark, Brahminy should have paler tail feathers. Or is it just the lighting in the photos??

wgeoff

I have a friend who visits the Philippines regularly who suggests this is a Common Buzzard also, too pale underwing for a Brahmini Kite. So I accept Common Buzzard, thanks to Tung, Matthew and John for their comments.

The 21st April latest spring record mentioned by John is from 1985.