The whole question is really quite complex. Migratory birds can't really be
considered to have 'maintained' a breeding population here, but we still count
them. Then what about waders that turn up periodically - Hudsonian Godwit, for
example? Presumably listers are still able to tick them? Then, what about
Grey-headed Lapwing? Isabelline Wheatear? And so the complexities multiply.
In terms of one's own life list, you just need to be happy with the rules you
apply to yourself. And if you want to compare and contrast life lists, then
you just need to be using 'common' rules.
Anyway, that's my two bob's worth.
John Tongue
Ulvertsone, Tas.
On 27/11/2009, at 9:55 AM, Dave Torr wrote:
> 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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