Field Testing of Protocols to Prevent the Spread of
Zebra Mussels Dreissena polymorpha during Fish Hatchery and Aquaculture
Activities
W.J.
Edwards, L. Babcock-Jackson, D.A. Culver-2002
North
American Journal of Aquaculture, 64(3): 220–223
Abstract:
The
zebra mussel Dreissena polymorpha, an introduced, aquatic bivalve species,
causes changes in the ecology and negatively impacts the economic value of
infected water bodies. Unfortunately, the spread of the zebra mussel can be
facilitated by aquaculture activities. We field-tested the effectiveness of
chemical treatment protocols established to prevent the spread of
microscopic zebra mussel larvae (veligers) during fish stocking. We achieved
more realistic exposure conditions by performing fish and veliger toxicity
tests in aerated 750-L tanks on fish hatchery tanker trucks using the
chemical treatments established in earlier laboratory work. Posttreatment
survival was measured for veligers in the 750-L tanks, followed by an
assessment of the survival of walleye Stizostedion vitreum and saugeye
(sauger S. canadense × walleye) 5 d after stocking into 4,000-m2
fish ponds. A 1-h pretreatment of 750 mg/L KCl followed by a 2-hr treatment
of 25 mg/L formalin was effective in killing veligers without causing fish
mortality. However, the addition of 0.5% NaCl to alleviate transport stress
in fish did not increase fish survival and left many veligers alive.
(The
Ohio State University, Department of Evolution, Ecology, and Evolutionary
Biology, 1735 Neil Avenue, Columbus, Ohio 43210, USA)