The split of Cackling Goose left seven subspecies. Whilst large feral populations occur in the UK, most are the nominate race canadensis,
with a few other subspecies, notably maxima. Genuine wild birds do occur, but
identification is difficult since some races are clinal and not all feral geese are Greaters. The front bird in the third photo shows some characteristics of hutchinsii, which is a Cackling Goose, but it is
feral and almost certainly a hybrid. The best way of assigning birds to any particular subspecies, or whether wild or not, is the location of the sighting
and the other birds accompanying the vagrant (i.e. not Greylags) There is however a possibility that wild birds, once here, may mix with a feral flock and remain. The most likely wild subspecies to be identified in the UK
are interior and parvipes.
