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Folks,

Having been on many shockerboats (several times an armada) for surveying
redhorse suckers (Moxostoma), in-and-out river water, open circulation works
well.  With closed circulating containers during summer, water changes often
are needed to keep temperature down.

My question is, have any workers noted greater susceptibility of redhorses to
stress / death in holding containers than, say, percids, centrarchids, minnows,
trouts?

   Thank you,

         Bob Jenkins      Roanoke College, Salem, VA, USA
___

"James B. Reynolds" wrote:

> >
> In my experience, no one has ever used a closed holding tank while
> electrofishing just to avoid contamination of the water body. The fish and
> water  in the tank are from the water body itself and would not be a source
> of contamination other than diseases or toxins already contained therein.
> If the tank itself was a source of pathogens or toxins, there is a bigger
> issue to deal with than the one of closed vs open tank systems!
>
> Closed systems are usually used in electrofishing because the tanks are
> small and can be easily aerated (fish are usually not held for very long so
> a large tank is generally not needed). However, electroshock is stressful
> and a poor holding environment makes recovery even more difficult.
> That's why I always recommend a flow-through system with at least a
> partially-closed lid; you get ambient temp and oxygen while providing
> "cover" to help the fish recover.
>
> Dr. James B. Reynolds

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