On Thu, 21 Mar 1996, Dale Goble wrote:

>
> some of the postings have suggested that the various feral
> parrot/parakeet species might be negatively affecting other, indigenous
> species. this raises two questions in ecological theory:
>
> 1. in a mature, undisturbed ecosystem, are all "niches" filled so
> that the introduction of a new species is necessarily at the expense of
> an established species?
>
Dale--

this sounds like a good question...how would we find out?

[snip...]
>
> it does not seem improbable that there are empty "niches" in seattle
> because some species have been eliminated.
>
yeah..well, maybe the niches, if there are any, were created
by the introduction of other exotics..

I really don't mean to sound like some purist activist here..
it just seems to me that we don't really know the extent of
the damage they may be creating..i.e., what species are they bumping
out of those cavities they were seen peering into?

And with all due respect, Ray...is it really a bad thing that
the colony at PDX is displaced?

Tom