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        Discussion Area 討論區 >> Bird Identification 鳥類辨識 >>  Unsure raptor at Mai Po
        
(Message started by: Neil on Sep 27^th, 2006, 6:56am)

Title: Unsure raptor at Mai Po
Post by Neil on Sep 27^th, 2006, 6:56am

Photographed yesterday on one of the best days at Mai Po for some time. Is it an Eastern Marsh Harrier? The second view is the only other one I have. Neil

Mai Po Nature Reserve 米埔自然保護區
26/9/2006
Nikon D2x plus Nikon 300/f4 AFS lens

http://www.pbase.com/neilfif11/image/67589852.jpg
http://www.pbase.com/neilfif11/image/67612754.jpg

Title: Re: Unsure raptor at Mai Po
Post by Paul Leader on Sep 27^th, 2006, 10:35am

Neil,

Do you have more pictures of this bird you can post, especially of the upperparts?

Title: Re: Unsure raptor at Mai Po
Post by Paul Leader on Sep 28^th, 2006, 3:02pm

Whilst superficially this looks like an Eastern Marsh Harrier, I am not sure that it is and I strongly suspect that it is a Pied Harrier.

There are a number of features which to me suggest Pied:

1) Looking at the underwing it is clear that it has moulted the secondaries, hence it is not a juvenile. This also means it is probably a second year bird, which also means that the primaries have not been moulted i.e. they are juvenile primaries. If so, then they are classic juvenile Pied primaries with silvery grey along the basal half, more so on the outer primaries and contrasting strongly with the blackish fingers. The hint of barring on the inner primaries is also typical of juvenile Pied.

2) The wing formula fits Pied. In EMH the second to fifth primaries are of almost equal length with the second and fifth being slightly shorter but by a similar length. On Pied, primaries two, three and four are the same length, five is obviously shorter and the tip falls about half way between the tips of primaries one and two.

3)The breastband is very narrow

4) The head and bill look small and delicate compared to EMH

5) The upperparts look very dark which I believe is a pro Pied feature

6) The pale leading edge is quite reduced and does not go back onto the median coverts

7) The buffy tail tip is a feature of juvenile Pied, although to be honest I am not sure if it is also a feature of juvenile EMH.

Photos of an EMH in comparable moult and plumage can be found at

http://www.orientalbirdimages.org/search.php?p=7&action=searchresult&Bird_ID=834&Bird_Family_ID=&pagesize=1

see also subsequent photos of the same bird.

I am not 100% sure about the id of this bird so would be very interested in comments from others

Title: Re: Unsure raptor at Mai Po
Post by Neil on Sep 29^th, 2006, 6:55pm

Paul,
Thanks for your detailed explaination. I'll send it out to a couple of other places and see what people say. Neil.