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administered. The fish was placed in a bucket of fresh water and allowed to recover from the effects of the anesthetic. After it had regained equilibrium, the fish was released into slow water near the capture location. Attempts to relocate radio-tagged fish occurred as time permitted, so no specific relocation schedule was followed, and areas with poor access were searched less frequently than areas with abundant access. Relocation was accomplished with a scanning radio receiver (Advanced Telemetry Systems). Statistical Analyses All statistical calculations were performed with SAS statistical package version 6.11 (SAS Institute, Inc. 1995). Comparisons through time were made by stratifying the data by year collected. Data were also stratified between the Canyon and Woodside sections to make comparisons through space. Chi-square tests were calculated with Proc Freq to determine differences in the percentages of adult and subadult fish through space and time. The following criteria, based on the size of mature individuals captured and literature values, were used to distinguish between adults and subadults: flannelmouth suckers, 400 mm (McAda and Wydoski 1985, personal observation); Colorado pikeminnow, 400 mm (Seethaler 1978); bluehead suckers, 200 mm (personal observation); channel catfish, 300 mm (Carlander 1969); common carp, 250 mm (personal observation). Descriptive statistics were calculated with Proc Means and Proc Freq, and analysis of variance tests were calculated with Proc GLM. All outcomes with a probability level of less than or equal to 0.05 were considered to be significantly different. RESULTS Habitat Sampling Spring peak discharge near Woodside was approximately 2,550 cubic feet per second in 1996 and 3,260 cubic feet per second in 1997 (personal estimation based on U.S. gauge data collected above Helper), but spring peaks have often exceeded 4,000 cubic feet per second (Figure 3). The peak discharge in 1996 was not as high as it could have been due to early releases from Scofield Reservoir. This flow regime was used in order to keep the reservoir level low enough so that repairs could be made to the dam. A spike flow caused by a hail storm, rather than by operation of Scofield Dam, occurred in early September. This fall peak was larger than the spring peak, but lasted for only a few days, and corresponded to a precipitous drop in the water temperature of the Price River and the Green River (Figure 4). Similar fall peaks in discharge occur nearly every year (U.S. Geological Survey, unpublished data}. Low flows in the Price River were approximately 30 cubic feet per second in 1996 and 1997 (personal estimation based on transect data). However, the discharge of the Price River has dropped below 10 cubic feet per second during several of the years on record (Figure 3). Biological oxygen demand, fecal coliforms, total phosphorus, iron, gross alpha and beta radiation, and total dissolved solids in the Price River often exceed limits recommended by the Utah Division of Water Quality (Table 2). Some of these parameters are probably influenced by human activity in the watershed, but no cause-and-effect relationships were determined. 6