Who says they have to be resident? Don't they just have to be here? You
couldn't count a Hudsonian Godwit that was captive, or had escaped from
captivity, but everyone assumes they've just flown here accidentally because
that's the most likely thing.
Same for things like Galahs, which could be escapees. You just assume they
aren't, because that's probably true. It's only with species that are likely
to be escapees or free roaming pets that there's any need to investigate.
Can you count any waders that have been banded? They're all escapees, aren't
they?
Peter Shute
-----Original Message-----
From:
On Behalf Of Carl Clifford
Sent: Friday, 27 November 2009 11:07 AM
To: John Tongue
Cc: ; Bill Stent
Subject: Re: [!! SPAM] Re: [Birding-Aus] Peafowl
Perhaps "migratory" waders should be regarded as resident species that travel
elsewhere to breed. Most species of waders seem to spend more time out of their
breeding range than in it. This could be argued to apply to most migratory
species.
Cheers,
Carl Clifford
On 27/11/2009, at 10:35 AM, John Tongue wrote:
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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