Seems one of the ongoing questions on Birding-Aus is "is xxxx a tickable
population". There seem to be two easy alternatives - either we count no
introduced birds or we count them all. That would save a lot of debate I
guess.... :-)
Slightly more seriously - I guess it is very hard for anyone to determine in
many cases whether the population has been self-sustaining for the required
period of time (10 years I believe?). How do we know for any of these
populations whether or not there have been further releases to boost the
population - I recall that someone reckoned the Melbourne Bayside Barbary
Doves were being replenished by further releases from time to time? Does
being fed artificially stop them being self-sustaining?
2009/11/27 Bill Stent <>
> I feel somehow that the Melbourne populations aren't tickable, but I'm
> looking for a good reason why not.
>
> I'd be surprised if there were more than a dozen or so, which would suggest
> they might be partially supported by human feeding (although I've got no
> actual evidence for this).
>
> Bill
>
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