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Subject: Is it female Northern Shoveler? 是雌琵嘴鴨嗎﹖ [Print This Page]
Author: msamuel    Time: 21/10/2008 20:54     Subject: Is it female Northern Shoveler? 是雌琵嘴鴨嗎﹖

18Oct2008 at Mai Po
But it has blue patch on wing.


[ Last edited by msamuel at 26/10/2008 22:27 ]
Author: puppymic    Time: 21/10/2008 21:07

yes

http://www.hkwildlife.net/viewth ... &extra=page%3D2

http://www.hkwildlife.net/viewth ... &extra=page%3D2
Author: Beetle    Time: 21/10/2008 21:08

It has the characteristic Bill size and shape of Northern Shoveler.
A juvenile male instead?
Author: puppymic    Time: 21/10/2008 21:26

Quote:
Original posted by Beetle at 21/10/2008 21:08
It has the characteristic Bill size and shape of Northern Shoveler.
A juvenile male instead?
個咀又好似係比較大喎

Immature Male
http://orientalbirdimages.org/se ... _ID=&pagesize=1
Author: lpaul    Time: 21/10/2008 21:31

The pale disc in front of the eye, dark patch near bill and extensive blue on the forewing show that it is actually an eclipse (i.e. non-breeding adult) male.
Author: msamuel    Time: 21/10/2008 22:04

I think I got it.  Other than normal male and female adults, there is also non-breeding male adult which I guess will look more like a female than a male.
Then another question comes to my mind immediately.  Is it the Northern Shoveler himself chooses not to mate or due to some physical/healthy conditions it becomes non-breeding?
Thanks everybody anyway.  Samuel
Author: ajohn    Time: 22/10/2008 11:22

In most duck species, after breeding the birds carry out a very rapid complete moult and lose most of their flight feathers at the same time. This obviously makes flying difficult and males in full breeding plumage would be easily seen and vulnerable to predation. They therefore carry out a complete body moult into a female-like plumage and then moult back into breeding plumage in the wintering grounds. This female-type plumage is eclipse (not non-breeding plumage as it doesn't necessarily mean that the bird hasn't bred this year.

You will notice over the next few weeks/months that arriving ducks are all in female-like plumage and that the males will gradully start to grow brighter colours to attract a mate.



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