At 13:01 6/04/99 +0930, you wrote:
>Hooray!, at last someone else who knows that decimation only reduces pops by
>ten percent each time. Congrats Russ!
>I hate the way people ( I guess they are also the unwashed) misuse this word.
>
>Tony.
>
>At 11:45 6/04/99 +1000, you wrote:
>>
>>> Well of course if the gulls did get one out of every ten chicks, then they
>>> would have decimated them, literally. Decimation is not devastation,
>>> decimation is a rather trivial event in natural populations, unless it is
>>> done repeatedly. All other factors remaining equal, decimation needs to
>>> occur 7 times to halve the population i.e. 100%, 90%, 81%, 72.9%, 65.6%,
>>> 59%, 53.1%, 47.8%.)
>>
>>Not really related to the original message, but, given Philip Veerman's
>>interesting figures above, does anyone know if the gulls' 'success rate'
>>would increase from 10% as the tern population decreased?
>>
>>Russell Woodford
>>
>>
I think the congrats should go to Philip who posted the initial definition, but
then Russell raises the interesting point of future gulls' success.
I think that it could go either way. With a decreasing tern population, there
may be less mobbing of the gulls, so their success might increase.
On the other hand a small tern population might mean leaner pickings for the
gulls which might then "switch" to another food source which was more
profitable.
There's probably many other factors involved.
Cheers
Peter Woodall
Dr Peter Woodall email =
Division of Vet Pathology & Anatomy
School of Veterinary Science & An. Prod. Phone = +61 7 3365 2300
The University of Queensland Fax = +61 7 3365 1355
Brisbane, Qld, Australia 4072 WWW = http://www.uq.edu.au/~anpwooda
"hamba phezulu" (= "go higher" in isiZulu)
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