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Re: Dealing with the real fish? problem



On Thu, 25 Jun 1998, mcclurg luke e wrote:

Your post is quite good as it raises many of the important issues we have been
discussing.  Please don't take any of my comments personally, I'm not trying
to beat on you, just the issues involved.

> "once caught, never released" has been interesting. 

My interpretation of what NFC means by this is that any non-native fish once
caught is not returned alive to the water.  A non-native fish is any that
didn't originally occur in that waterbody.  Obviously exceptions to this exist
as at times threatened species are sometimes put elsewhere when they can no
longer inhabit their native range.

(And actually, I just thought of one deliberate translocation that has had
conservation benefits and that is the Sacramento perch.  It is now virtually
extinct in the Sacramento River (CA), but is common in many lakes outside it's
natural range.  It was originally stocked for angling purposes.)

My personal stand is the same, although I'll extend it beyond it's original
use by NFC to say that once a fish has been removed from it's habitat and
taken home it should never be returned to the wild.  If one brings a fish
home, adds it to their fishrooms, then puts it back where they caught them it
provides a risk of introducing diseases that are not already present since
aquarium stuff comes from all over the world.  No fishroom is free from
disease and few folks practice quaranteen proceedures necessary to prevent
their spread between tanks.  
 
> In Kansas, there is quite a bit of catching, transporting, and
> re-releasing of fishes.  I have done it myself, just two days ago as a
> matter of fact, with Channel Cats, Bass and various Sunfishes.  Generally,
> I can catch something from a lake or river and transport it to one of our
> family owned farm ponds.

You could be doing things like spreading diseases potentially from one
watershed to another.  Albeit your intentions in all of this are good, however
you are likely not aware of the dangers of this, hence my point about a lack
of education amongst most aquarists.  It's not really your blame, the "system"
just isn't working the way it should to be effective.

> Anyway, I have stocked several ponds with Bluegills, Largemouth Bass and
> Sunfishes caught from various localities througout the state.

With exotic fish this doesn't matter so much that they came from various
localities (except in regards to disease).  However, you shouldn't mix native
fish from different locations, or put them in ponds where they are likely to
escape and mix with local stocks.  Fish vary in many potential ways between
locations, genetically, behaviourally, etc etc.  The term local adaptation
here is most appropriate.  If you mix stocks which are not locally adapted to
one that is you often end up with an inferior genetic stock.  These processes
may not be reversable. 

> All fish caught were legal to keep I might add. 

That's part of my whole point.  We base our justifications on the law, not
what is right or wrong since that is typically a personal judgement with
which everyone differs. (and I'm not trying to pass judgement on you here)
That's why I think having the laws is important even if they aren't enforced.  

> As far as the non-game species I have caught and then released many of
> them on the shorelines.  I haul in a trap and then sort through what I
> want and put the rest back.  

There is little wrong with releasing native fish at their point of capture at
the same time you catch them. 

> Pumpkinseeds are supposed to be introduced
> in this state, but I have thrown them back.  Ditto with Red Eared Sunfish.
> I do this because the State and Federal agencies have determined them to
> not be threat to the native fauna. (and destroying them MAY be illegal!) 
> If I caught a Jewel Cichlid or a Pacu, it would be 'dead meat'.

How is a pacu different to a sunfish?  How often are state agencies right
regarding what is a threat and what is not?  We all make mistakes sometimes
too remember.

> What's good for
> Arizona or California just may not be applicable to Kansas and Missouri.

My specific statement regarding moving fish around is applicable everywhere in
the world if the goal is to leave natural fish assembledges for future
generations.  It is based on a princible, not geography.

> While the
> removal of exotics to protect endangered species and eco-systems is to be
> applauded, not every introduced species is an exotic.  Remember, nature is
> constantly changing and new species replace old ones.  That fish you
> consider to be exotic or introduced MAY have made it there through a
> natural process and deserves it's right to colonize.

Every introduced species _is_ exotic.  Fish do not recognise political
boundaries, they recognise watersheds (broadly speaking).  It's going to be a
hell of along time before bluegills ever swim over the Rockies.  The type of
processes you describe here take millions of years and alot of chance.  When
was the last time you know of a fish that naturally expanded it's distribution
without human help?  It doesn't happen very often.

I hope you take these comments in the general light they are meant.

Thanks too for keeping the discussion going, I think your comments were very
timely and appropriate.

Tootles

Peter J Unmack 			peter.unmack at asu_edu
---------------------------------------------------------------
DESERT FISHES RULE: To boldly thrive where no other fish can make it!

Australian desert fishes pages at http://ozdesertfish.base.org (don't 
forget to visit the Desert Fishes Council pages too)
Native Fish Australia pages at http://www.nativefish.asn.au
North American Native Fishes Association at http://www.nanfa.org 
Aquatic Conservation Network at http://www.acn.ca



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