---------- Forwarded message ----------
Date: Thu, 06 Feb 1997 10:38:19 +0000 (GMT)
From: George Turner <gft at SOTON.AC.UK>
To: Multiple recipients of list CICHLID-L <CICHLID-L at NRM.SE>
Subject: Re: [acn-l] Re: Hybrids (fwd)
>cross posted from acn-l
>
>---------- Forwarded message ----------
>Date: Thu, 06 Feb 1997 08:27:25 +1100
>From: Bruce Hansen <bhansen at ozemail.com.au>
>To: acn-l at acn.ca
>Subject: Re: [acn-l] Re: Hybrids (fwd)
>
>The anecdotal recollection of Les Kaufman about the hybrid offspring
>preferring their own company rather than that of either parent is
>interesting. Of course they were ONLY CICHLIDS but it does in a small way
>support the contention that accidental hybrids in the wild may not
>necessarily lead to wholesale "deterioration in the genetic purity" of our
>existing stocks in our streams as some of our well-known pundits would have
>us believe.
>
>
Dear Bruce
I am not quite sure what you are getting at here. Les's comments indicate
that the hybrids might prefer to shoal together, but it doesnt say what they
will mate with. Even if they do prefer to mate with other hybrids (and
therefore might not lead to introgression- 'deterioration of genetic
purity'), it is important to bear in mind that in the wild there will be
mortality of all broods and also dispersal. Therefore when hybrids become
sexually mature, they may find there are no other hybrids to mate with, and
in these circumstances could easily end up breeding with native fishes.
There is plenty of evidence that introduced populations often lead to
introgression with native forms, particularly when they are from different
races, but the same species as the native fishes (e.g. through deliberate
stock introduction of hatchery-reared salmonid populations in an attemp to
increase production for anglers).
I think deliberate introductions are dangerous, often ineffective and do
often lead to loss of local genetic diversity.
Anyway what is the ANGFA?
George
Dr G.F.Turner
Lecturer in Ecology/ Biodiversity
Division of Biodiversity & Ecology
University of Southampton
Bassett Crescent East
SOUTHAMPTON SO16 7PX
England, UK
Phone- 44-(0)1703 594394
Fax- 44- (0) 1703 594269
e-mail gft at soton.ac.uk