Interesting data Kent.
As I read it all of the last 5 (non-historical) occurrences have either
appeared in October (3 records) or April/May. These occurrences are
obviously during the migration seasons for arctic-nesting geese. To
dismiss these birds as "origin uncertain" one would have to hypothesize
that they somehow jumped their cages and then got caught up in the
north-south migrations of genuine wild geese. This is feasible, but is
it not equally likely that they are genuine wild birds that have gone
My point is that BRCs have got themselves into a cul de sac by assuming
that for a bird to be fully accepted as a genuine vagrant we need to
show beyond a reasonable doubt that it is not an escapee. This, as well
as being unscientific, is impossible for most individual birds (how do
you prove a negative?). The barnacle goose that was banded by Steve
Percival in Scotland and turned up in the US is the very rare exception.
Is it not much more reasonable to assume that such a bird is a genuine
vagrant, unless there is some definite evidence to the contrary?
Hector Galbraith PhD
Galbraith Environmental Sciences LLC
837 Camp Arden Rd., Dummerston, VT05301
802 258 4836 (phone)