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Auteur Topic: Are those immature male and female Baikal Teal?  (gelezen 237 keer)

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Alcedo atthis

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Are those immature male and female Baikal Teal?
« Gepost op: maart 05, 2009, 16:26:24 pm »

Gelogd
greetings,
Jörn Lehmhus

Alcedo atthis

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Are those immature male and female Baikal Teal?
« Reactie #1 Gepost op: maart 06, 2009, 14:07:29 pm »

While we are at it- what do you think of the middle bird here????

http://www.leszoosdanslemonde.com/images/z...007_1_small.jpg
Gelogd
greetings,
Jörn Lehmhus

Alcedo atthis

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Are those immature male and female Baikal Teal?
« Reactie #2 Gepost op: maart 08, 2009, 19:03:53 pm »

and here is a probable baikal teal x eurasian wigeon:

http://www.clanga.com/gallery/Ptaki%20rzad..._mpolakowsk.jpg
Gelogd
greetings,
Jörn Lehmhus

Justin Jansen

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Are those immature male and female Baikal Teal?
« Reactie #3 Gepost op: maart 14, 2009, 13:46:50 pm »

Still think that a good oversight of plumages of first-year Baikal Teal might help. Do you hold some examples Jorn?
Gelogd
M.v.g., Justin Jansen

J&L

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Are those immature male and female Baikal Teal?
« Reactie #4 Gepost op: maart 14, 2009, 14:10:32 pm »

Ik zit toch op Waarneming.NL????? :wacko:  :P  
Gelogd

Alcedo atthis

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Are those immature male and female Baikal Teal?
« Reactie #5 Gepost op: maart 14, 2009, 22:27:09 pm »

No, this is Waarneming.international :grin:

The reason being , the Netherlands seem to be one of then centers of occurrance of odd waterfowl hybrids in Europe.
(Due to having so many people who breed waterfowl???)

So, allthough I have quite some experience in identification of odd hybrid waterfowl, there are several where I don´t know further...the 2nd link here shows such a case.

so you´ll probably finsd some more threads started by me that make the hybrid forum a bit  waarneeming.international...
Gelogd
greetings,
Jörn Lehmhus

Alcedo atthis

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Are those immature male and female Baikal Teal?
« Reactie #6 Gepost op: maart 14, 2009, 22:32:28 pm »

Concerning the Polish bird:
I agree that a good oversight of plumages of first-year Baikal Teal might make things easier, but there don´t seem to be any on the web.
However, I still think it is fairly clear that the Polish bird can not be a pure baikal teal. here are my thoughts as to why:

If you look at the bird in question you see quite a lot of things that resemble Baikal Teal (Anas formosa). But there are also a lot of things that do not quite match:

1. There is a grey triangular panel on both sides of the bill. (Baikal teal should have an uniformely coloured, all dark bill)

2. The dark pattern on the head which goes over the eye, should be very narrow behind the eye. Also the iridescent area within this dark pattern should show green iridescence , not coppery iridescence. Also there should be at least a trace of the fine white line above this dark pattern, which goes from above the eye to the back of the head, And there is only ahint of the black line going over the cheeks.
So there are quite a lot of things wrong for Baikal teal with this head pattern.

3. The breast pattern is quite dark for Baikal teal and there are nearly no black spots on the breast

4. The white vertical flank stripe is not there, that area is covered by a coloration similar to the breast, but a bit lighter at the place of the white stripe.

5. The vermiculations on the flank are fine, but coarser than they should be in a Baikal teal.

6. The scapulars are close to Baikal teal, but shorter and the coloration is less brilliant.

7. The pale area on the base of the tail is not rusty red as it should be in Baikal teal, but cream coloured. Also it is slightly reduced in size.

 


Compare with Baikal teal Anas formosa adult males (breeding plumage):

http://www.flickr.com/photos/stevegreaves/3292905199/

http://www.flickr.com/photos/lucavale82/2535341543/

http://www.flickr.com/photos/mrsminib/2519524100/


and with Baikal teal Anas formosa males (moulting):

http://www.naturephoto-cz.eu/anas-formosa-picture-3830.html

http://www.flickr.com/photos/ken_san/3014920142/

Unfortunately I have not much experience on first winter males of  Baikal teal and there seem to be no pictures of first winter males on the web.
However, I think only some of these odd features might be explained by a first winter male (Like the shorter and less brilliantly coloured scapulars),
but others in my opinion can not be explained by a first winter male (like the odd bill pattern and the extention of the breast coloration over the vertical flank bar).

In general, as far as I know, Baikal teal hybrids can be close to Baikal teal in appearance. For example look at this Hybrid Anas formosa x Anas acuta:

http://ujihala.ld.infoseek.co.jp/hybrid_Ducks/pixbaiT.html

or a bit more intermediate as this probable Hybrid Anas formosa x Anas crecca:

http://www.flickr.com/photos/14195020@N08/2950649605/

However, most Baikal teal hybrids seem to have the uniformely dark bill of  Baikal teal. But the Polish bird has these pale grey triangular areas on the bill.
I know only one group of ducks whose hybrids with darkbilled species show such a bill pattern. This group of ducks are the wigeons. See as an example this
Hybrid Anas penelope x Anas crecca:

http://ujihala.ld.infoseek.co.jp/020312/duckwexte.html

That hybrid Anas penelope x crecca shows a bill pattern similar  to the Polish bird and shows also an  extention of the Wigeon breast coloration to the flanks, similar to the Polish bird.
The shape of the area of brownish breast coloration is also similar in Hybrids Anas penelope x Anas platyrhynchus:

http://users.utu.fi/hlehto/photo/hybrid/aplapen5.shtml

http://www.kustobsar.se/main/bilder/bilder.asp?artkod=280

http://www.flickr.com/photos/33236701@N07/3186980515/


The shape of the area of brownish-pink breast coloration is also similar in Hybrids Anas penelope x Anas acuta:

http://waarneming.nl/foto/view/621864

http://waarneming.nl/foto/view/621867

As seen in the previous photos of hybrids Anas penelope x Anas acuta, they can also have a similarly coloured dark head patch and similary colored buffish cream cheeks as the Polish bird.  

So while the Polish bird clearly has Baikal teal genes, there must be something else in there-and to me the best fit for the other species is Eurasian Wigeon (Anas penelope). Several of the odd features shown by the Polish bird are also expressed by other Anas penelope hybrids.


 
Gelogd
greetings,
Jörn Lehmhus
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