NANFA-- Fw: Gambusia affinis researching

Todd Crail (
Wed, 2 Apr 2003 09:42:33 -0500

Hi all,

Here's a fella that was interested in learning about Gambusia behavior and
affects in regard to sport stocking, as well, in regard to their affects on
other species. I've already mailed back and forth with him... Real nice guy

Would any of you have information concerning these studies that he's
requesting? Please email him directly if you wouldn't mind. His email is


----- Original Message -----
From: Bill Leopold
Sent: Friday, March 07, 2003 4:29 PM
Subject: Gambusia affinis researching

Mr. Todd Crail,

Greetings! I have found your address via the NANFA regional outreach page on
the website. I have a rather specific request for information, and was
wondering if you or your collegues in the organization may have something

I work for a private fish hatchery near Cincinnati, OH. We have recently
started listing Mosquitofish (Gambusia affinis) in our catalog, and soon on
our website when the revisions are updated. This has been pushed by the past
two years with the West Nile Virus invasion. As a result, we are seeing more
and more customers requesting the stocking of Mosquitofish into their private
lakes and ponds, many of which are used primarily for sportfishing activity.

I have seen some interesting reports and comments on the potential problems of
stocking gambuzi in ponds with established gamefish populations. Most relate
to gambuzi predation on gamefish eggs and thereby reducing reproductive
success of desirable species. The trouble is most articles seem to be two
decades or more old, and I haven't located anything specifically addressing
the negative impacts of gambuzi minnows on gamefish (bass, bluegill species,
other minnow/shiner forage fish species) populations. Moreover, I am looking
for scientific evidence for or against any effects.

So, that being said I was wondering if you would know anyone who has recently
been involved in Gambusia affinis researching activity, and if you or they
might have any references pertinent to this question? I would appreciate any
help, especially if it does help our customers more effectively manage their
ponds without undesirable influences and effects.


Bill Leopold
Bill Leopold
Fishery Biologist
Jones Fish and Lake Management
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