Puzzling Goose (hybrid?), Rostock, NE Germany, Feb 2020 (1 Viewer)

[CARERY]

A friend photographed this orange-billed Anser sp. a few days ago. I think it should be a hybrid but then, geese are not my strong point... So, I'd be happy to get your opinion!

 

[Jefferson Shank]

Greater White-fronted Goose for me.

 

[Nutcracker]

In the first pic, there's a nice Greater Whitefront at the far left, several [Taiga?] Bean Geese, and the odd bird 2nd from the right - I'm assuming it is this last one is the mystery bird. I'd suspect yes a hybrid; the bill is too long for Whitefront, so perhaps Whitefront x Bean, or Whitefront x Greylag.

 

[lupokatja]

Yes, the one to the right definitely looks the part for a Greater Whitefronted Goose x Tundra Bean Goose hybrid. They can be quite variable though and many are more subtle than this one. No Taiga Beans here though.

Lützen

 

[Jefferson Shank]

Yes, the one to the right definitely looks the part for a Greater Whitefronted Goose x Tundra Bean Goose hybrid. They can be quite variable though and many are more subtle than this one. No Taiga Beans here though.

I agree. All Greater White-fronted Goose except for the hybrid.

 

[CARERY]

Thanx for the opinion so far... so a hybrid, as I suspected. What age would you say it is?

 

[Maffong]

I agree. All Greater White-fronted Goose except for the hybrid.

You're causing quite the confusion here. They're Tundra Bean Goose, one Greater White-front and one hybrid

 

[Joern Lehmhus]

agree on probable hybrid tundra bean x greater whitefront...
I didn´t see anything speaking against adult?

 

[Brett Richards]

agree on probable hybrid tundra bean x greater whitefront...
I didn´t see anything speaking against adult?

Why not a Greylag x White-front? It is a large, large-billed bird.

Brett

 

[aeshna5]

I agree. All Greater White-fronted Goose except for the hybrid.

Definitely Bean Geese in there!

 

[stevethehydra]

The big, all-orange bill does make me thing Greylag x GWF, but the wing pattern looks identical to the Bean geese. I'm wondering if Greylag x Bean might also be a possibility, as white around the bill can show up in other goose hybrids that don't actually involve either "white-fronted" species.

 

[lupokatja]

Why not a Greylag x White-front? It is a large, large-billed bird.

Brett

I am not really familiar with those, but I would expect a more Greylag-like structure like this:

https://oudeversie.waarneming.nl/waarneming/view/134984162

Also, hybrids GWFG x TBG seem to be much more common than GWFG x Greylag, or so it appears here in the Netherlands.

Lützen

 

[lupokatja]

The big, all-orange bill does make me thing Greylag x GWF, but the wing pattern looks identical to the Bean geese. I'm wondering if Greylag x Bean might also be a possibility, as white around the bill can show up in other goose hybrids that don't actually involve either "white-fronted" species.

The orange bill is a well-known feature of this hybrid (although pinkish bills seem to be slightly more common), and it is therefore a known pitfall for Greenland GWFG in the Netherlands (for the unwary).

Lützen Portengen

 

[lupokatja]

agree on probable hybrid tundra bean x greater whitefront...
I didn´t see anything speaking against adult?

Me neither, but it can be really difficult to see in late winter. If it was just the single (non-hybrid) GWFG with Tundra Beans that just might be the mother/father, in which case the hybrid would likely be a first winter bird.

Lützen

 

[Joern Lehmhus]

Me neither, but it can be really difficult to see in late winter. If it was just the single (non-hybrid) GWFG with Tundra Beans that just might be the mother/father, in which case the hybrid would likely be a first winter bird.

Lützen

But family bonds can be longer in geese I think?
However I agree it is not 100% safely ageable

 

[Joern Lehmhus]

greylag x whitefront never look so bean goose like. the one Lützen linked is a good example in my opinion.

The bill in tundra bean goose is quite strong and these suspected hybrids tundra bean x greater whitefront have also occurred several times in Germany. In many respects they are quite tundra bean goose like....

for comparison:

here is a captive hybrid greylag x greater whitefront from France, with a greylag (with some domestic genes?) in the background

https://i.skyrock.net/6123/71856123/pics/2841811930_1.jpg

some more probablye hybrids:
here is another greylag x greater whitefront

https://www.flickr.com/photos/63362568@N05/5765673651/

another
http://birdhybrids.blogspot.com/2014/02/greater-white-fronted-goose-x-greylag.html

another
https://iveneverkilledapipit.files.wordpress.com/2011/12/white-front-greylag-hybrid.jpg

another without white front
https://i.skyrock.net/5255/35045255/pics/2313358505_1.jpg

wha you note there is that none has the extremely orange legs of greater whitefront, though some may come close

 

[CARERY]

Thanx everyone, very interesting discussion! As there seems to be the consensus GWFG being one of the parents I would have expected some black belly patches if adult, no? That's why I thought it should be an immature...

 

[lupokatja]

Most of the hybrids I have seen were 1st winter birds, but the few returning individuals have all shown very limited (and mostly no) barring, a bit like this bird (3rd photo):

https://oudeversie.waarneming.nl/waarneming/view/73553468

Recent phylogenetic studies also suggest closer genetic links between the Bean Goose complex and the Whitefronted Geese than between either and the Greylag Goose.

https://www.sciencedirect.com/science/article/pii/S1055790316301105

Alternatively available here:
https://kops.uni-konstanz.de/bitstream/handle/123456789/36533/Ottenburghs_0-379362.pdf


Lützen Portengen

 

[Joern Lehmhus]

I agree with that. Most of these birds do not show the greater whitefront barring on the belly. (If it occurs it seems to be much more restricted than in greater whitefront)

It also is correct for hybrids of greater whitefront with other Anser species . in general such hybrids do not show the barring. I can say that seems true for
greater whitefront

x barheaded
x snow
x emperor
x greylag

only greater x lesser whitefront show it but it seems to be reduced compared to greater

(and greater whitefront x branta species also dont show this)

 

[Brett Richards]

I'm posting this photo just out of interest - a Greyla Goose with a white blaze, photographed at Scarborough Mere, Yorkshire, England on 17 February. There doesn't seem to be any other species involved.

Brett