Several years ago, as part of some research I was doing to rebutt the feral
ferrets argument, I took the time and expense to call New Zealand and spoke
to someone about the attempt to introduce ferrets into the wild and the
resulting impact the feral colony has had.  I was told by this Dept. of
Wildlife Management (or some such title) that the attempt to introduce
ferrets was considered to be a dismal failure and that it is very unlikely
that any of the ferrets released survived.  Any existing colony would
consist of polecats which were tried after the ferrets failed.  Or, at best,
a hybrid of the polecats and any surviving ferrets.  But this is unlikely
because of the time betweeen the releases of the two.  It is quite possible
this person doesn't know what he is talking about (we know government
officials have been known to speak with authority on subjects they have no
knowledge of.).  However, this is the closest thing to an "official'"
government statement I've been able to come up with on the subject.
 
Bottom Line:   According to the government of New Zealand they have no feral
ferret population.  Even though they tried to create one.
 
[FM]
[Posted in FML issue 1761]