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Soortgroepen => Wat is dit voor vogel? / Determinatie => Vogels => Hybriden => Topic gestart door: Alcedo atthis op mei 07, 2007, 16:13:04 pm

Titel: hybrid gadwall x northern shoveler
Bericht door: Alcedo atthis op mei 07, 2007, 16:13:04 pm
http://www.flickr.com/photos/30418455@N00/...6604255/detail/ (http://www.flickr.com/photos/30418455@N00/sets/72157600166604255/detail/)

a gadwall x northern shoveler, always an interesting hybrid.
Titel: hybrid gadwall x northern shoveler
Bericht door: laatvlieger op mei 07, 2007, 16:29:00 pm
A really odd looking animal!

What bothers me most is off course the white throat en cheeks and also the reddish brown breast, which donīt fit on both species...  
Titel: hybrid gadwall x northern shoveler
Bericht door: Alcedo atthis op mei 07, 2007, 17:00:46 pm
Here is a Mallard x Northern shoveler for comparison:

http://www.netfugl.dk/pictures.php?id=list...species_id=1012 (http://www.netfugl.dk/pictures.php?id=listpictures&species_id=1012)


 
Titel: hybrid gadwall x northern shoveler
Bericht door: Alcedo atthis op mei 08, 2007, 10:45:02 am
http://www.ascabird.org/gadshov.jpg (http://www.ascabird.org/gadshov.jpg)

Another Gadwall x Shoveler, though the colours on this photos are not that good to judge.

But you see the same head pattern and also (though difficult to see, the breast seems to have a reddishbrown touch.

A stuffed Museum specimen of this hybrid is also shown in one of the Gillham books on hybrid ducks.

It also shows the redishbrown breast and the same odd head pattern
Titel: hybrid gadwall x northern shoveler
Bericht door: JohanvantBosch op mei 08, 2007, 13:38:23 pm
Citaat
http://www.ascabird.org/gadshov.jpg (http://www.ascabird.org/gadshov.jpg)

Another Gadwall x Shoveler, though the colours on this photos are not that good to judge.

But you see the same head pattern and also (though difficult to see, the breast seems to have a reddishbrown touch.

A stuffed Museum specimen of this hybrid is also shown in one of the Gillham books on hybrid ducks.

It also shows the redishbrown breast and the same odd head pattern
I've seen one of these hybrids once, it looked a lot like this last bird. It behaved like a shoveler, by the way. Which is logical, because it almost had the same bill, so it had to feed in the same way.
Titel: hybrid gadwall x northern shoveler
Bericht door: laatvlieger op mei 09, 2007, 18:24:57 pm
I still can't believe it really is this hybrid. In all the hybrids we've seen so far in this forum, you could always find back a lot of both parents in the hybrid. In this specimen it is so curious. The white throat, chin and cheecks, the strange dark breast.. It just doesn't fit.

Is it absolutely sure that it really is this hybrid?  
Titel: hybrid gadwall x northern shoveler
Bericht door: Alcedo atthis op mei 09, 2007, 19:17:45 pm
I am quite convinced...

the "pale cheek" pattern is also seen in some hybrids gadwall-mallard and Gadwall x Common Teal ; though less extreme .

and hybrids of shoveler with other species (Common teal or Cinnamon teal for example) also show some white areas in the face , though none of the parenst has this in full breeding plumage.

 The reddish breast is a surprise however.
Titel: hybrid gadwall x northern shoveler
Bericht door: laatvlieger op mei 09, 2007, 19:20:11 pm
Citaat
though none of the parenst has this in full breeding plumage.

 
Well, they also lack this white in other plumages.. Both parents never show this pattern of white in the face.
Titel: hybrid gadwall x northern shoveler
Bericht door: Alcedo atthis op mei 09, 2007, 20:06:14 pm
Yes,

but what I wanted to say (didnīt explain it properly , I think) is that the capped head pattern is a trait hidden in gadwall and expressed in some gadwall hybrids.

while white in the face is a trait of the shoveler group (see australasian shoveler, or BWTeal, and male northern shovelers have a pattern  similar to australasian shoveler somewher during moulting-see the links)
and also expressed more in some hybrids


some moulting shovelers with white in the face:

http://vancouverislandbirds.com/feb11shoveller1.jpg (http://vancouverislandbirds.com/feb11shoveller1.jpg)

http://www.pbase.com/jeanchiasson/image/55393190 (http://www.pbase.com/jeanchiasson/image/55393190)

http://www.dereila.ca/dereilaimages/Shoveler2.jpg (http://www.dereila.ca/dereilaimages/Shoveler2.jpg)


and here a shoveler x cinnamon teal (expresses the white in the face):

http://www.azfo.org/gallery/noshXcite.html (http://www.azfo.org/gallery/noshXcite.html)

Therefore I think the white cheeks are just a combination of hidden features of both species




 
Titel: hybrid gadwall x northern shoveler
Bericht door: JohanvantBosch op mei 09, 2007, 22:56:58 pm
Citaat
Citaat
though none of the parenst has this in full breeding plumage.

 
Well, they also lack this white in other plumages.. Both parents never show this pattern of white in the face.
The one I saw had the same head pattern, reminiscent of female red-crested pochard. For the rest there was no doubt as to what were the parents:
- the body was exactly like a gadwall male
- the  bill was exactly like that of a shoveler...
So it is not that strange that the bird in this topic would show this head pattern...
Titel: hybrid gadwall x northern shoveler
Bericht door: laatvlieger op mei 10, 2007, 09:25:42 am
That's funny, I only knew these eclipse (moulting) forms of northern shoveler:
http://waarneming.nl/foto_details.php?id=21492 (http://waarneming.nl/foto_details.php?id=21492)
and
http://waarneming.nl/foto_details.php?id=83470 (http://waarneming.nl/foto_details.php?id=83470)
They've got dark area's near their bill, in your examples this area is white..


All your examples come from the american populations of shoveler, my examples come from our dutch birds. Do you think this might be a differnce in moulting pattern between the different subspecies? (although, I don't even know wheter subspecies exist in northern shoveler... )
Titel: hybrid gadwall x northern shoveler
Bericht door: laatvlieger op mei 10, 2007, 09:33:56 am
Hmm I'm not sure wheter my observations are right. Although it seems that the dutch moulting birds posses more black near the bil they also show some almost white border near this black area (like the american birds)  
Titel: hybrid gadwall x northern shoveler
Bericht door: laatvlieger op mei 10, 2007, 09:40:50 am
Apparently no subspecies are known.