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Hello, fellow fish ecologists!
A colleague and I are interested in surveying fish species using nearshore
(shallow water) habitats over rocky (gravel/cobble/boulder) bottoms in
western Lake Erie. We would greatly appreciate insights or advice from
members of this group.
The target envrironment is not well-sampled using trawls (bottom too rocky)
or electrofishing (too deep). Various traps like fyke nets or small minnow
traps have anchoring problms and are highly susceptible to storm effects.
Gill nets will be ineffective for species that are too small for the mesh,
or that have various avoidance skills. Double beam and split beam
hydroacoustic equipment may be useful for mid-water collumns, but isn't
effective very close (0.5-1.0 m) to the bottom. I don't know much about
the utility of other electronic sampling methods. Problems I've
experienced with my SCUBA-based surveys largely center on
avoidance/approach behavior on the part of various fishes. I'm considering
the application of rebreather technology to cut down on diver noise and
shiny bubbles--but there is also the problem of the personnel and
time-intensive nature of the work. The use of ROV's or "drop" video cameras
suspended from the boat may be effective for this purpose, but I'm guessing
they problems too (I've not used either).
We suspect rocky-bottom, nearshore habitats constitute a potentially
important ecosystem within lacustrine environments that has not been
well-studied with traditional sampling methods. These areas may represent
an ecological island of exposed hard substrate habitat within a sea of
muddy lake bottom that could prove important, even critical habitat for
many fishes of both game and nongame species. Any suggestions of sampling
methods to consider, problems and pitfalls to avoid (in our proposed
efforts to test various sampling regimes), or relevant references to the
problem would be gratefully received and shared with the group. Thanks
very much.
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Ken Baker E-Mail: [log in to unmask]
Department of Biology Phone: (419) 448-2224
Heidelberg College FAX: (419) 448-2124
Tiffin, OH 44883-2462
"The aim of science is not to open the door to everlasting wisdom, but to
set a limit on everlasting error." ...Bertolt Brecht
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