Re: NANFA-L-- Another Michigan comment

Todd D. Crail (tcrail-in-UTNet.UToledo.Edu)
Tue, 19 Apr 2005 13:47:44 -0400

>> Several of the trout fishermen have ask to come on our sampling trips.
The DNR fishery person present was also interested in me giving a talk to
them on minnow, dater killifish captive propagation.<<

Great work guys! I think these types of interactions are critical, and many
may be suprised-in-how many agency folks, sportsmen, and naturalist
societies are interested and _engaged_ in/with the work we're doing. It
seems to me-in-times that Aquarium Club interactions are what get emphasized
as the outreach to do, but I've found very little interests from aquarists
to go out and get wet. I've presented to 3 aquarium clubs now, and the
burning question-in-the end is "Where can I buy these fish?" There's
nothing wrong with that, certainly... But if it's your goal to get people
outside and become active in conservation, I'd look-in-my former list of
places to present and become active.

>>A DNR fisheries person commented that before we cleaned up the polution in
the great Lakes it was what was keeping things like the zebra mussels and
round gobies out. They used to die when dumped from balast water. I never
thought there was a dark side toi cleaning up polution.<<

And it doesn't even stop there... As early as 1995 it was discovered that
native freshwater sponges are making a small rebound in the Great Lakes to
the point where they're _outcompeting_ zebra mussels in some patches
(Ricciardi, Snyder, Kelch, Reiswig, 1995). The sponges wouldn't be there
unless the zebra mussels were creating the microhabitat where they exist.
Pretty good thing from the sponge's point of view huh? There are gobs of
papers on how zebra mussel colonies are the perfect habitat for a gob of
macroinvertebrates that were doing quite poorly prior to the invasion.
Pretty good from their point of view too... Not to mention fishes that are
profiting from eating them.

Turbidity seems to keep the zebra mussels out of the Maumee River (although
quagga mussels are starting to increase, as they're much more goo tolerant)
and may explain why the zebra mussels have pretty much stopped dead in their
tracks in the plains streams. In the paper I threw in a few weeks ago, we
were talking about zebra mussels facilitating the spread of round goby
( By keeping the
zebra mussels out, we exclude the round gobies from making an upstream move
from Lake Erie into the watershed that could possibly polish off the
pathetic populations of greenside and johnny darters in the lower Maumee,
and have an overall effect on the logperch populations.

So do we maintain a heavy silt load in the rivers, leaving them turbid to
keep the zebra mussels out of the picture? OR would a reduction in
turbidity reduce the strain on the darters enough that they could overcome
ensuing invasion? What about the native mussels in the stream...? Would
they benefit from removing the "sublethal" effects of turbidity (reduced
feeding efficiency, reduced breeding capability) with a cleanup, or would
the costs of the ensuing zebra mussel invasion wipe out another stream?

There's always a push and pull in nature whenever something is changed, and
it becomes very difficult to determine what is useful and what is not.
There is no black and white, canned answer.

Well there is one... Keep the danged things out in the first place!!! :)

But that usually seems to be little help these days. Which unfortunately
puts things in a less desireable position where you have to make resonable
decisions about where to push and where to pull.

The Muddy Maumee Madness, Toledo, OH
It's never too late to have a happy childhood.

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