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        Discussion Area 討論區 >> Photo Gallery 相片分享 I >>  Crested Serpent Eagle 蛇鵰
        
(Message started by: Daniel CK Chan on Jul 30^th, 2003, 11:51pm)

Title: Crested Serpent Eagle 蛇鵰
Post by Daniel CK Chan on Jul 30^th, 2003, 11:51pm

071 Crested Serpent Eagle 蛇鵰
Tsim Bei Tsui 尖鼻咀
05/7/2003
Canon EOS10D, 1/640, f5.6, +1, ISO200, 50% Full Frame
http://www.danielckchan.com/b20030273-0600.jpg
http://www.hkbws.org.hk/fileServer/PhotoG/daniel_chan01/danielchancseagle01.jpg

Title: Re: Crested Serpent Eagle ??
Post by Mike Kilburn on Aug 1^st, 2003, 9:36am

congratulations Daniel! I haven't seen the Ng Tung Chai bird on its perch for some time, but with such a good flight shot doesn't really matter-la!

Mike

Title: Re: Crested Serpent Eagle 蛇鵰
Post by KK Hui on Aug 1^st, 2003, 4:57pm

Excellent shot, Daniel! ;D ;D ;D

500 + 1.4x ??

Best
kk
--------------
www.geocities.com/kkhui_001

Title: Re: Crested Serpent Eagle ??
Post by Daniel CK Chan on Aug 1^st, 2003, 11:07pm

on 08/01/03 at 09:36:32, Mike Kilburn wrote:

congratulations Daniel!  I haven't seen the Ng Tung Chai bird on its perch for some time, but with such a good flight shot doesn't really matter-la!

Mike

Mike,

Thanks. Would it be a 1st or 2nd year immature bird?

KK,

The photo is shot with 500+1.4+Wimberley Head.

Daniel

Title: Re: Crested Serpent Eagle ??
Post by Mike Kilburn on Aug 2^nd, 2003, 10:12am

I'm not an expert on aging raprtors, but in the photo you can see that it is moulting its inner primaries. These new feathers have a contrasting strong black tip and a broad white band across the feathers.

When they grow to full length this will become the classic broad white bar with a black border along the rear edge of the wing which is the diagnostic feature for flying CSEagle.

However the feathers which are not yet moulted have narrower brown lines and the tips are no so dark. This is typical juvenile plumage. I do not know how long this plumage is retained and would welcome the opinions of others, especially those who know about the moult strategies of eagles.

You can also see that the spotting on the breast and belly is well defined as an adult would show, but raptors moult these feathers first and then replace their fligth feathers during the summer.

"Birds of Prey in Japan" states that juvile plumage is replaced by full adult plumage by the end of the autumn of the second calendar year. This would correspond with the plumage of this bird. so my guess (I stress Guess!) is that it is a second year bird which will be in full adult plumage by the end of the year!

Cheers
Mike

Title: Re: Crested Serpent Eagle ??
Post by Daniel CK Chan on Aug 2^nd, 2003, 11:28am

on 08/02/03 at 10:12:02, Mike Kilburn wrote:

I'm not an expert on aging raprtors, but in the photo you can see that it is moulting its inner primaries.  These new feathers have a  contrasting strong black tip and a broad white band across the feathers.

When they grow to full length this will become the classic broad white bar with a black border along the rear edge of the wing which is the diagnostic feature for flying CSEagle.

However the feathers which are not yet moulted have narrower brown lines and the tips are no so dark. This is typical juvenile plumage.   I do not know how long this plumage is retained and would welcome the opinions of others, especially those who know about the moult strategies of eagles.

You can also see that the spotting on the breast and belly is well defined as an adult would show, but raptors moult these feathers first and then replace their fligth feathers during the summer.

"Birds of Prey in Japan" states that juvile plumage is replaced by full adult plumage by the end of the autumn of the second calendar year.  This would correspond with the plumage of this bird. so my guess (I stress Guess!) is that it is a second year bird which will be in full adult plumage by the end of the year!

Cheers
Mike

Many thanks for your informative explanations. If your guess is true, I strongly want to see or take photos of him/her again by the end of this year when he shall show his/her beautiful full adult plumage. ::)