Re: NANFA-- Bluenose shiner news

Steffen Hellner (steffen_at_hellner.biz)
Sun, 21 Sep 2003 20:31:16 +0200

I agree with your statement that biotop protection comes first. But if this
failes - and there is lots of evidence for it - we only have the chance to
preserve the species, on what population basic ever. If we take your look at
genetic level as limitation then we would have to let the Panda go, let
Cynopsittaca spixi go, the nosefrog (one of two species is already extinct
obviously), tha Japanese Ibis and hundreds of other species which we keep or
kept in captivity and released to the wild again or which we try to safe in
the wild on a genetic basis which is way too small to have the "rare genes"
present. Most species differentiated from others on the basis of very few
numbers of specimens. If the "rare" genes were that important for nature,
they wouldn4t be that rare and we would only have a handfull of species
compared to the diversity we really find.

I see one mayor difference to what I mean in your example of the salmons.
Re-introducing a species to its former range or habitat is a lot different
from trying to introduce a species into the range of another one which is
its sibbling ecologically. This is comparing apples and cherries.

Genetics is a great field. But the genes are only the playground and toys
for nature. The game however makes it! ;-)

Steffen

> Von: Jay DeLong <thirdwind_at_att.net>
> Antworten an: nanfa_at_aquaria.net
> Datum: Sun, 21 Sep 2003 11:14:39 -0700
> An: nanfa_at_aquaria.net
> Betreff: Re: NANFA-- Bluenose shiner news
>
> At 07:40 PM 9/20/2003 +0200, you wrote:
>> Perfect example with the invaders! Nature is strong, stronger than we
>> suggest and that shows in this example. Captive bred fish can well survive
>> in the wild if a population of sufficient numbers in set out. It even
works
>> with little numbers as inveders show.
>>
>> Captive bred fish in general still keep the ancient potential inside,
except
>> for very high bred mutants like black angelfish or lyrateil forms etc. A
>> bubbleeye goldfish won4t make it long, sure. But a Danio will most
prabably,
>> and a bluehead shiner as well.
>
> I don't see how instances of the havoc created by introduced fishes suggest
> that an "ancient potential" (?) exists, or that fish introductions are
> successful because Nature is that way. There are numerous examples of
> failed attempts to release and establish wild populations of non-native or
> captive reared fish. Take the Atlantic salmon mess in the Pacific
> now. For years fishery agencies deliberately tried to get Atlantics in the
> Pacific northwest, but efforts failed time and time again-- eggs, fry,
> adults, everything. It's ironic that when everyone was kind of on the same
> page that it was a bad idea, it happened accidentally and now there are
> Atlantics established in Pacific rivers. I understand your optimism but
> this notion of "ancient potential" overlooks genetic science and the
> problems with captive breeding such as domestication-- reducing the
> population to small number then breeding those individuals resulting in the
> permanent loss to the whole species of rare genes, because it's these rare
> genes that allow for adaptation and survival of the species. The biggest
> disservice we can do for fishes is talk about individual animals as though
> they hold some magic secrets to their species. Fish species are about
> populations, and populations are defined in the context of their
> environment and the selective pressures under which they came about:
> chemical, biological, physical, whatever. Habitat conservation is the way
> to save species and species diversity.
>
> --
> Jay DeLong
> Olympia, WA
-
> /"Unless stated otherwise, comments made on this list do not necessarily
> / reflect the beliefs or goals of the North American Native Fishes
> / Association"
> / This is the discussion list of the North American Native Fishes
Association
> / nanfa_at_aquaria.net. To subscribe, unsubscribe, or get help, send the word
> / subscribe, unsubscribe, or help in the body (not subject) of an email to
> / nanfa-request_at_aquaria.net. For a digest version, send the command to
> / nanfa-digest-request_at_aquaria.net instead.
> / For more information about NANFA, visit our web page,
http://www.nanfa.org
/-----------------------------------------------------------------------------
/"Unless stated otherwise, comments made on this list do not necessarily
/ reflect the beliefs or goals of the North American Native Fishes
/ Association"
/ This is the discussion list of the North American Native Fishes Association
/ nanfa_at_aquaria.net. To subscribe, unsubscribe, or get help, send the word
/ subscribe, unsubscribe, or help in the body (not subject) of an email to
/ nanfa-request_at_aquaria.net. For a digest version, send the command to
/ nanfa-digest-request_at_aquaria.net instead.
/ For more information about NANFA, visit our web page, http://www.nanfa.org