Tunrda Bean Goose x Barnacle Goose

Tunrda Bean Goose x Barnacle Goose hybrid (with Tundra Bean Geese), Oost (Texel, Netherlands), 30th December 2016 - copyright Diederik Kok

(photo ID: 3006)

The pale cheek with a reddish brown lower rear section reminds me of some Red-breasted Goose hybrids but I don't think that can be the case here.  I've never seen Tundra Bean x Red-breasted but based on how White-fronted Goose x Red-breasted Goose hybrids look I would expect a darker body and a more obviously smaller bird.  So I think Barnacle Goose seems the better solution for the white-cheeked parent.  It would be difficult to say for sure what the grey goose parent was but the fact that it is surrounded by Tundra Bean Goose makes that a pretty good bet - and the bright orange legs and pale belly are certainly consistent with that.



Tundra Bean Goose Anser serrirostris (formerly Anser fabalis rossicus)
Barnacle Goose Branta leucopsis

Tundra Bean Goose x Greater White-fronted Goose

probable Tundra Bean Goose x Greater White-fronted Goose hybrid (with Tundra Bean Geese), Oost (Texel, Netherlands), 29th December 2016 - copyright Diederik Kok

(photo ID: 3004)

Convincing examples of hybrids between some of the wild Anser species that occur in Europe are surprisingly hard to come by.  Perhaps that is because the hybrids are genuinely scarce, or perhaps it is hybrids are difficult to detect and even harder to prove, with variation in parent species considerable.  I suspect it's the latter but maybe in time this will become more clear.  This one looks like a promising candidate to me, although proving it is not an odd but genetically pure Tundra Bean Goose is not straightforward.

The white round the base of the bill is not enough on its own to reject pure Tundra Bean Goose - quite often they have a little white round the bill.  Usually this is broken on pure birds, not surrounding the whole of the upper mandible in a continuous line.  Not only is it continuous here but it's quite broad at the top too.  Perhaps that is possible in pure Tundra Bean - it wouldn't surprise me if so - but this bird also has a lot of dark shading behind the white, something that I don't recall seeing to this extent on a Tundra Bean Goose.  The extent of orange on the bill may not be too excessive for Tundra Bean Goose (though is not usual) but it also seems to have a pinky tone to it.  I think in combination these features point to a likely hybrid origin, although I am troubled by how perfect the rest of the bird looks for Tundra Bean Goose.  Maybe it is just a very unusual Tundra Bean Goose, but I am more convinced by this bird being a hybrid than others I've seen where the hybrid ID has been suggested.

In addition Diederik thought this bird called differently from the Tundra Bean Geese.  He has a recording of it at waarneming.nl.  I think it's quite a subtle difference, but that may be because I don't hear Tunrda Bean Geese calling often enough!

As always, comments are welcome!

probable Tundra Bean Goose x Greater White-fronted Goose hybrid (same bird as in photo ID 3004 above; with Tundra Bean Geese), Oost (Texel, Netherlands), 29th December 2016 - copyright Diederik Kok

(photo ID: 3005)

Tundra Bean Goose Anser serrirostris (formerly Anser fabalis rossicus)
Greater White-fronted Goose Anser albifrons

Tundra Bean Goose x Pink-footed Goose

possible Tundra Bean Goose x Pink-footed Goose hybrid, or possibly just a Pink-footed Gose (with Pink-footed Geese - the subject bird is the one behind the front Pink-foot), between Docking and Brancaster (Norfolk, UK), 17th November 2006 - copyright Dave Appleton

(photo ID: 0113)

Although it is sometimes said that Pink-footed Geese with orange legs are hybrids, I think the evidence for this is lacking (so far as I know).  Orange-legged Pink-feet turn up frequently and most of them resemble Pink-footed Goose in every other respect, so I do not think they are likely to be hybrids, even second or subsequent generation hybrids.

What is more unusual for pure Pink-footed Goose is orange tones on the bill.  The bill can look orangey when covered in a thin layer of mud, and some birds do have a slight orangey tone to the pink.  But despite looking at a lot of Pink-footed Geese I have never seen a bird with a clearly orange bill, except for this one.  Admittedly it wasn't as orange as on a Bean Goose, but clearly more orange than pink.  It also had bright orange legs, but showed no other clear evidence of Bean Goose involvement (and some features, for example the broad white tip to the tail, seem to rule out pure Bean Goose).

Some regular goose-watchers have looked at this and advised me that they feel it is most likely an odd Pink-footed Goose, and they may well be right.  For me the possibility of it being a hybrid remains, although I am by no means claiming it was one. Tundra Bean Geese frequently overwinter among the Pink-footed Goose flocks in Norfolk, sometimes remaining with them well into the spring.  It must be very likely that the odd bird remains with them during the breeding season and hybrids should be expected, and these hybrids are likely to be difficult to determine with certainty.  I hope more examples will come to light so that we can get a better understanding of what they should look like.

possible Tundra Bean Goose x Pink-footed Goose hybrid, or possibly just a Pink-footed Gose (with Pink-footed Geese - the subject bird is the one left of centre), between Docking and Brancaster (Norfolk, UK), 17th November 2006 - copyright Dave Appleton

(photo ID: 0114)

Tundra Bean Goose Anser serrirostris (formerly Anser fabalis rossicus)
Pink-footed Goose Anser brachyrhynchus