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        Discussion Area °Q½×°Ï >> Photo Gallery ¬Û¤ù¤À¨É I >>  Besra ªQ³¶ÆN
        
(Message started by: Thomas_Chan on Oct 16th, 2005, 2:11pm)
Title: Besra ªQ³¶ÆN
Post by Thomas_Chan on Oct 16th, 2005, 2:11pm
http://www.hkbws.org.hk/fileServer/PhotoG/thomaschan/thomaschan_113.jpg
http://images4.fotop.net/albums3/ThomasChan/Japanese_sparpowhawk/oct_16_05_4.jpg

http://www.hkbws.org.hk/fileServer/PhotoG/thomaschan/thomaschan_114.jpg
http://images4.fotop.net/albums3/ThomasChan/Japanese_sparpowhawk/oct_16_05_6.jpg

16/10/2005
Tsim Bei Tsui ¦y»ó©C
Leica 800mm + 20D
ISO200 f5.6 1/640s, 1/800s
Title: Re: Japanese Sparrowhawk ¤ê¥»ªQ³¶ÆN
Post by Kwok Jai on Oct 16th, 2005, 5:24pm
they are male besra, if japanese sparrowhawk the tail should be shorter
Title: Re: Japanese Sparrowhawk ¤ê¥»ªQ³¶ÆN
Post by Falcon on Oct 16th, 2005, 7:21pm
Could it be a Crested Goshawk?
Title: Re: Japanese Sparrowhawk ¤ê¥»ªQ³¶ÆN
Post by Thomas_Chan on Oct 16th, 2005, 7:59pm

on 10/16/05 at 19:21:28, Falcon wrote:
Could it be a Crested Goshawk?


Falcon,

 I don't think they are  Crested Goshawk.
 Because its size like a Dove and its flying also like
 a Dove, its tail longer than Dove.

Thomas.
Title: Re: Japanese Sparrowhawk ¤ê¥»ªQ³¶ÆN
Post by Thomas_Chan on Oct 16th, 2005, 8:16pm

on 10/16/05 at 17:24:16, Kwok Jai wrote:
they are male besra, if japanese sparrowhawk the tail should be shorter


Kwok Jai,

 Thanks for your identify!
 Why they are male, not a couple?

Thomas.
Title: Re: Besra ªQ³¶ÆN
Post by Kwok Jai on Oct 16th, 2005, 9:00pm
because two birds size no different, if they are a couple some one should be bigger than next one.
Title: Re: Besra ªQ³¶ÆN
Post by David_Diskin on Oct 16th, 2005, 9:03pm
I'm not sure these are Besras. Given their bulky-looking structure and the long 5th primary especially evident in the first photograph, I'd say they're adult Crested Goshawks.

dave diskin
Title: Re: Besra ªQ³¶ÆN
Post by Koel_Ko on Oct 17th, 2005, 6:14am
Purely from the photos, I would say that the first one is a male Besra and the second one gives two Crested Goshawks.

The first bird has visibly thin feet, long 5th primary which creates a 'sharp' wingtip more indicative of Besra than Crested, and a relatively short bill that points towards Besra.

The second photo shows two birds with broad, rounded wings and bulky rear body, which seems to favour Crested Goshawk.
Title: Re: Besra ªQ³¶ÆN
Post by Thomas_Chan on Oct 17th, 2005, 7:30am
David Diskin, Koel Ko,

Thanks for your reply!
The birds were so far away for me that I couldn't take
clear photos.
I give you another two potos that may help to identify.
http://www.hkbws.org.hk/fileServer/PhotoG/thomaschan/thomaschan_115.jpg
http://images4.fotop.net/albums3/ThomasChan/Japanese_sparpowhawk/oct_16_05_5.jpg

http://www.hkbws.org.hk/fileServer/PhotoG/thomaschan/thomaschan_116.jpg
http://images4.fotop.net/albums3/ThomasChan/Japanese_sparpowhawk/oct_16_05_7.jpg

Thomas.
Title: Re: Besra ªQ³¶ÆN
Post by Thomas_Chan on Oct 17th, 2005, 7:48am

on 10/16/05 at 21:00:56, Kwok Jai wrote:
because two birds size no different, if they are a couple some one should be bigger than next one.


Kwok Jai,

 Thanks for your reply!
 How to explain their chest in difference colour?

Thomas.
Title: Re: Besra ªQ³¶ÆN
Post by David_Diskin on Oct 17th, 2005, 8:53am
I agree with Koel Ko that the two birds together are Crested Goshawks, The single bird does appear less bulky etc. than the Crested Goshawks, suggesting Besra.

However, in a recent discussion about some photos of accipiters taken at Po Toi, the wing formula of a male Besra shows the longest feathers to be P3 & 4, followed by 5, 2 ,1. The bird in the photo above seems to show P5 to be longer than P3.

Perhaps this is a variable feature and is of no significance when it comes to ID??

dave diskin
Title: Re: Besra ªQ³¶ÆN
Post by Kwok Jai on Oct 17th, 2005, 4:22pm
Thomas

this is  about the age.If adult male, the breast always has orange colour, but the immature birds the breast should be no orange.so the left bird is a adult and next is a imature.



kwok jai
Title: Re: Besra ªQ³¶ÆN
Post by gjcarey on Oct 18th, 2005, 4:43pm
Structurally, the two birds appear to me to be Besras. They seem rather small and compact, with relatively short wings. The underwing coverts are heavily marked, which does not fit Crested Gos. Finally, does Crested Gos show orange irides? I don't remember ever having noticed this, while it is a consistent feature of adult male Besras. In addition, the head and upperparts, and especially the tail, of one of the birds, at least, appear rather too grey for Crested Gos.

Geoff
Title: Re: Besra ªQ³¶ÆN
Post by David_Diskin on Oct 19th, 2005, 8:05am
Thanks to Geoff for putting me right on this one. Interesting points.

Now where did I put that stamp collection .... ?

dave diskin
Title: Re: Besra ªQ³¶ÆN
Post by Koel_Ko on Oct 19th, 2005, 4:31pm
Agreed. Thanks to Geoff for pointing out these features. Learned a lot from this forum!  :)
Title: Re: Besra ªQ³¶ÆN
Post by Thomas_Chan on Oct 19th, 2005, 9:09pm

on 10/18/05 at 16:43:32, gjcarey wrote:
Structurally, the two birds appear to me to be Besras. They seem rather small and compact, with relatively short wings. The underwing coverts are heavily marked, which does not fit Crested Gos. Finally, does Crested Gos show orange irides? I don't remember ever having noticed this, while it is a consistent feature of adult male Besras. In addition, the head and upperparts, and especially the tail, of one of the birds, at least, appear rather too grey for Crested Gos.

Geoff


Geoff,

Thanks for your clearly explaination and identify!
For my first scene, they were like Spotted Dove.
Their size and flying were more like Spotted Dove, only
their tail is longer than the Dove. That make me turn
the camera to them...

Thomas.


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