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Recovery goals developed for humpback chub in 2002 indicated actions should be taken to minimize the adverse effects of parasites on humpback chub in the Little Colorado River. One objective in that document, was to identify the level of tapeworm control that would be necessary to remove harmful impacts on humpback chub and to develop an Asian tapeworm control program (USFWS 2002). Evaluating the use ofPraziquantel to remove Asian tapeworm is the first step in this process. Although temporary effects of tapeworm infestation and quantification of tapeworm loads can be achieved using Praziquantel, the potential of large scale treatments to control Asian tapeworm in natural systems is limited. The use of Praziquantel will likely be restricted to bath treatments to remove tapeworms from fish prior to translocation or to alleviate short term impacts and increase growth rate. Treatment of individual fish to remove tapeworms without holding may be possible. Fish captured during routine monitoring could be treated to remove tapeworms by inserting a Praziquantel solution down the throat with an eye dropper. The efficacy and safety of these methods still need laboratory evaluation. The long term effectiveness of such methods will also depend the rate of tapeworm re-infestation. Our field results demonstrate that tapeworm loads in endangered fish can be removed and accurately quantified in the field for monitoring purposes without dissection, provided that adequate water quality can be maintained in treatment containers for a 24-hour period. Acknowledgements I thank Scott Rogers, Teresa Hunt, Anne Kretschmann, Randy Vanhaverbeke and Dewey Wesley for assistance collecting fish. John Rinne and Quent Bradwisch provided laboratory research facilities and research specimens. Pam Sponholtz and Shaula Hedwall assisted with permitting issues. Bill Persons and Brian Clark provided helpful reviews of this manuscript. These experiments were conducted with support from the Arizona Game and Fish Department under permit number TE821577-0.