Goose Hybrids UK, October (1 Viewer)

[AlanR]

A flock of Canada Geese at Upton Warren (Worcs.) last month had a few 'white geese' among them. I don't think they are Greylags, Are they hybrids?
Alan

 

[Stephen Dunstan]

Look ok for Domestic Greylag types. I suppose the last one might have some Canada in it but not completely convinced.

Stephen.

 

[stevethehydra]

I'd say the birds in the 2nd and 4th photographs are definitely Canada x white/piebald domestic Greylag hybrids, having seen birds a lot like them. These hybrids can be anything between almost completely white (although usually with a few patchy-looking grey feathers) and almost completely dark (although nearly always with a white head/face), but the bill is the key difference between such hybrids and "pure" domestic Greylags - in these birds it's pink rather than orange and much slimmer than a typical Greylag bill, closer to Canada in shape.

Canada x Greylag hybrids also tend to have longer, thinner necks than "pure" domestic Greylags (although this feature can also come from Swan Goose ancestry, so don't rely on it), and hang around with Canadas rather than with Greylags. In general, to distinguish a Canada hybrid from a funny-coloured Greylag, don't look at colour (although pink bills and white heads are clues), but look at build and structure - hybrids are intermediate between the parent species (often closer to Canada).

I'm not sure about the other bird in the 1st and 3rd photos, as its bill, while pinkish, is closer to Greylag size/shape. Could still be a hybrid, or could possibly be their <I>Anser</i> parent.

 

[fugl]

I'd say the birds in the 2nd and 4th photographs are definitely Canada x white/piebald domestic Greylag hybrids, having seen birds a lot like them. These hybrids can be anything between almost completely white (although usually with a few patchy-looking grey feathers) and almost completely dark (although nearly always with a white head/face), but the bill is the key difference between such hybrids and "pure" domestic Greylags - in these birds it's pink rather than orange and much slimmer than a typical Greylag bill, closer to Canada in shape.

Canada x Greylag hybrids also tend to have longer, thinner necks than "pure" domestic Greylags (although this feature can also come from Swan Goose ancestry, so don't rely on it), and hang around with Canadas rather than with Greylags. In general, to distinguish a Canada hybrid from a funny-coloured Greylag, don't look at colour (although pink bills and white heads are clues), but look at build and structure - hybrids are intermediate between the parent species (often closer to Canada).

I'm not sure about the other bird in the 1st and 3rd photos, as its bill, while pinkish, is closer to Greylag size/shape. Could still be a hybrid, or could possibly be their <I>Anser</i> parent.

I agree with this.

 

[AlanR]

Thanks for the replies.
I am a bit surprised. I didn't think domestic or wild Greylags (Anser) could cross with Canada (Branta). I sort of assumed that they would have to be at least the same genus.
I just thought they looked a bit like Bar-headed hybrids!!
Alan
[Its hard enough identifying birds without hybrids!]

 

[fugl]

Branta x Anser crosses are actually fairly common. The offspring are seldom fertile, however, so gene flow between the 2 genera normally ends with the first generation. Here’s a probable Canada Goose x wild-type Graylag which turned up in Reno a few winters ago: http://www.flickr.com/photos/fugl/405195763/in/set-72157603523469680/

 

[Joern Lehmhus]

can only agree to stevehydra and fugl, all said...

in general very odd crosses are possible amoung the Anatidae, like wood duck x hooded merganser, wood duck x shelduck, Mallard x Eider, Mallard x Egyptian goose, Greylag x Mute swan, Canada goose x black swan etc. Though these intergeneric crosses are in general infertile (a few exceptions might be possible)

 

[stevethehydra]

Wow, i'd heard of most of those (and seen pics of the Mallard x Eider (which has a really crazy head pattern) and Mallard x Egyptian), but am still surprised by those last 2 goose x swan hybrids - by the size differences, and the fact that both Mute and Black Swans tend to hate and kill or drive off, rather than be attracted to, geese if nothing else!

Are there any pictures of goose x swan hybrids out there?

Also, has Mallard (or any other "duck") ever been known to hybridise with any of the smaller "true" geese? I've seen an extra-large domestic Mallard apparently paired up with a smallish Greylag, but never heard of a duck/goose cross - something that i'd imagine might have been tried by meat farmers...

 

[Joern Lehmhus]

Wow, i'd heard of most of those (and seen pics of the Mallard x Eider (which has a really crazy head pattern) and Mallard x Egyptian), but am still surprised by those last 2 goose x swan hybrids - by the size differences, and the fact that both Mute and Black Swans tend to hate and kill or drive off, rather than be attracted to, geese if nothing else!

Are there any pictures of goose x swan hybrids out there?

Also, has Mallard (or any other "duck") ever been known to hybridise with any of the smaller "true" geese? I've seen an extra-large domestic Mallard apparently paired up with a smallish Greylag, but never heard of a duck/goose cross - something that i'd imagine might have been tried by meat farmers...

The so called "Schwans" from the Wohlensee in Switzerland, mother Mute swan, father a domestic goose (with domestic greylag and Chinese goose genes , so already a bit hybridized itself)...

http://www.birdlife.ch/nvw/Basisobjekte/schwans.jpg

canada x black swan:

http://elibrary.unm.edu/sora/Auk/v045n01/p0039-p0040a.pdf

and a bird from England with a great series of photos from Dave Appleton:

http://www.gobirding.eu/Photos/Swoose.php

Domestic mallard and domestic goose hybrids have been recorded, but even rarer than swan x goose. I have only seen photos of one which was more goose like in leg and body shape, neck length seemed intermediate and bill a bit more duck like, if i remeber correctly. those were old black and white photographs, and the bird was mainly white simimilar to the domestic parents.

 

[AlanR]

Well, as Lewis Carroll would have said, 'Curiouser and curiouser!'
Alan