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FEASIBIIITY OF DEVELOPING AND MAINTAINING A SPORT FISHERY IN THE SALT RIVER PROJECT CANALS Figure 9. A recaptured, June-stocked channel catfish being measured, weighed, and Floya tagged. below 100 (Anderson and Gutreuter 1983). Both K and Wr were presented in our results to evaluate the well-being of stocked and recaptured fish. Unfortunately, Wr is a new method, and species-specific standard weight (Ws) equations are only available for common game fish and a few nongame species. The most current standard weight (Ws) values for rainbow trout and channel catfish were used to calculate Wr (B. Murphy, Texas A and M., pers. commun., D. Willis, South Dakota State Univ., pers. commun.). Both stocking groups of channel catfish were combined to provide reliable comparisons of mean TL, weight, K, and Wr between the time they were stocked and recaptured. Potential Fish Tissue Contaminants Stocked and recaptured channel catfish and rainbow trout specimens were submitted to private laboratories for analysis of 129 priority pollutants listed by the U.S. Environmental Protection Agency (EPA) to assess public health risks. Fish from the original stocking groups were analyzed to determine baseline levels prior to stocking. After 5 months, recaptured channel catfish and rainbow trout were also analyzed for contaminant accumulation. Whole fish were wrapped in aluminum foil, sealed in plastic bags, labelled, and frozen (0 C) until laboratory testing (Environ. Prot. Agency 1979, 1993). Each composite (1 to 3 fish) was homogenized and then analyzed using established EPA methods (Environ. Prot. Agency 1979, 1993). The contaminants tested for included: pesticides, metals and inorganics, polychlorinated biphenyls (PCB) and related compounds, ethers, phenols and cresols, phthalate esters, halogenated aliphatics, polycyclic aromatic hydrocarbons, nitrosamines, and other nitrogen-containing compounds. Practical quantification limit (PQL) was used as the level of contaminant detection. This degree of detection provides a reliable reproduction of results by different laboratories using the same EPA analysis methods (Standard Methods 1989). We obtained from SRP a list of herbicides and biocides used in and along the canals to control vegetation from January 1992 through July 1994. In addition, SRP provided application schedules, descriptions of chemical use, a map of locations where chemicals were applied, and white amur 14 ARIZONA GAME & FISH DEPARTMENT, TECH REP. 18 B. R. WRIGHT AND J A. SORENSEN 1995