Friday, 21 February 2014

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

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