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buckets or 20-gallon Rubbermaid totes placed within the holding tank. These receptacles were perforated with slots on the sides but not on the bottom to allow water movement so that water quality was not compromised but capture and quantification of tapeworms from individual fish was enabled. Fish were provided with adequate space within each receptacle so that they could maintain normal swimming orientation and turn freely. Diffuser tubing placed in a grid on the bottom of the holding tank and a small submersible pump provided water movement and aeration. We covered the treatment receptacles with a mesh screen to prevent fish from jumping out and shaded the entire holding tank with a tarp. Water temperature in the treatment tank remained within :I:: 20C of river temperature throughout treatment. Water in the holding tank was treated with Praziquantel at a dosage of 1.5 mg/L. This was the lowest dosage found to be 100% effective at removing tapeworms in our laboratory trials. Twenty five ml of isopropyl alcohol was added to the Praziquantel to facilitate mixing. The holding tank was monitored throughout the treatment period and fish were placed in a net holding pen in the river and monitored for 1-hr following treatment. This allowed for monitoring of delayed effects of the treatment prior to being released. Tapeworms were quantified by collecting shed tapeworms or proglottid segments from each individual receptacle within the holding tank. Tapeworms were preserved in ethanol and individual tapeworm scolicies were counted. Positive identification of Asian fish tapeworm was made by verification ofthe characteristic arrow-shaped scolex with a dissecting microscope (Heckmann and Deacon 1987). Treatment water was filtered through activated carbon to remove the Praziquantel (Dr. Richard Foust, Chemistry and Environmental Sciences, NAU, personal communication) and disposed of out of the river channel.