Re: NANFA-- Collecting ethics

Steffen Hellner (steffen_at_hellner.biz)
Tue, 13 Jan 2004 17:00:01 +0100

> You make a very good point here, that various human interventions can
> significantly affect allele frequencies in populations or species and have
> very dramatic effects in just a few generations. This is a major problem
for
> captive conservation programs. One of the more interesting examples of that
> is what has happened to several "arked" populations of Devil's Hole pupfish
> in USFWS operated refugia in the southwest. Keeping these populations in
> concrete pools has become a form of artificial selection, so that the
refuge
> populations have become bigger (if I remember correctly) and the males show
> different breeding coloration. Simply put, a measurably different fish was
> unintentionally created. Would they be fit if put back into Devil's Hole?
No
> one has tried that experiment...

The fact for Cyprinodon diabolis is that the form from Devils Hole we know
is a "starvation" form which stays smaller because of food resources.
Naturally this fish grows bigger and changes when offered different
conditions. It4s still the same fish as not genes changed but only
environment. But as most have a really "conservative" sight on conservation
any change in the phenotype is disregarded. I bet, when one day Devils Hole
dries up and the backup fish are put in again they4ll look the same as theyr
forebears very soon. But I rather don4t want this to happen.

As for the Apistogrammas. Especially these fish are bred with "steam" as we
say over here in large numbers and many forms show significant aberrations
(e.g. agassizii triple-red). Often they are raised artificially to make the
pair spawn again faster. But Mr. Roemer may be right with his research as I
don4t know the paper or the method and conditions.

Even if genes change over time in captivity, what they do in the wild as
well and without there would have been no evolution, this is from my mind
way better than losing a species. Of course any attempt should be made to
avoid this or to stretch this process.

Steffen
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