<< Despite their violence, flash floods seldom destroy fish populations, as
desert
fishes seek refuge behind boulders or along the banks when the floods occur.
>>
By no means am I in desert country (west Michigan), yet I have
experienced several instances where the fish seek refuge from turbid water
during flash floods. In a trout stream just down from my house, I used to
flyfish for shiner minnows because the trout were no longer living in this
downstream section of the watershed (operations have blocked off vital
springs, and over-fishing greatly reduced brown trout populations). I
remember fishing the creek one day after a torrential downpour. The current
breaks and channels that had held the shiners before had no fish, so I moved
to slower water behind a large island and caught tons of the minners on a
foam spider I had made. I ended up catching over 30 of them, because this was
one of the only places where they could find suitable refuge.
Anyways, that just came to mind after reading how the desert fish adapted
to floods. Today, that creek is extremely high, and the waterfall is gushing
with brown-yellow water. That creek has some of the biggest common shiners
Ive ever seen (up to 9 1/2"). I used to be able to go down there after school
and catch over 10 brown trout(I never kept a single fish) during a mayfly
hatch, but I haven't caught a single one down there for 4 years. Its nice to
see, however, that the chapter of trout unlimited I belong to is working on
the upstream stretches of the river (lunker structures, sand dredging,
spawning habitat, re-building s-curves, ect).
I blame much of the damage to farmers who have straightened the channels
and allowed excessive pesticides and herbicides to drain into the river. I
know I cannot generalize that all farmers do that, but a few careless
operations can really destroy a trout stream. In these cases, buffer and
filter strips would really do a stream a lot of good. They filter out
nutrients and runnoff that occurs both regularly and during floods. If the
silt, pesticides, and herbicides could be removed by the streamside
vegetation before reaching the river, natural reproduction would be more
possible. That is one of the major threats to coldwater habitats and our
watersheds, and it is non-point source pollution that can be avoided with a
little education and cooperation on the public's part.
Well, after steering slightly off subject I hope I have raised a bit of
awareness on non-point source pollution. I really support our project, and
other similar operations that encourage the use of filter strips in our
watersheds, its a step closer to clean water. __Dan McConnell Marshall,
MI
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