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was used to remove residual alcohol from the transmitters and prevent irritation of exposed tissue. After the transmitter was placed in the body cavity, the incision was stitched with absorbable chromic gut sutures. No antibiotics were administered. Fish were placed in a bucket of fresh water and allowed to recover from the effects of the anesthetic. After regaining equilibrium,, fish were released into slow water in the area from 0.2 to 3.7 miles downstream from Tusher Wash Diversion Dam. Relocation was accomplished with a scanning radio receiver (Advanced Telemetry Systems). Attempts to relocate radio-tagged fish occurred as time permitted, so no specific relocation schedule was followed. The river reach between Tusher Wash Diversion Dam and the town of Green River, Utah, was searched more frequently than locations upstream or downstream of that area. Statistical Analyses Statistical calculations were performed with SAS statistical package version 6.11 (SAS Institute, Inc. 1995). Analysis of variance tests were calculated with Proc GLM, while descriptive statistics were calculated with Proc Means and Proc Freq. Wilcoxon Rank-Sum Tests (Proc Nparlway) were used to analyze data that were not normally distributed and could not be transformed, due to a large number of zero values. All outcomes with a probability level of less than or equal to 0.05 were considered to be statistically significant. RESULTS Larval Entrainment Average temperatures in the Green River at Tusher Wash Diversion Dam ranged from 12.5° C to 15.9°C during the first sampling period and from 20.4°C to at least 23.9°C (the thermograph was not functioning during the entire sampling period) during the second sampling period (Figure 4). Total catch of larval fish was low in both the Green River and in the Green River Canal, even though large volumes of water were sampled in both locations. Native species, including Colorado pikeminnow, were caught in both locations (Table 2), although the numbers of sucker larvae captured were extremely low; no razorback sucker larvae were collected. Wilcoxon Rank-Sum tests showed that catch rates of Colorado pikeminnow were significantly higher in the Green River than in the canal. However, since the number of pikeminnow captured was very low, the validity of this significant difference is questionable. No significant differences in catch rates were noted for any of the other species captured (Table 3). Even though the number of Colorado pikeminnow larvae captured was lower in 1998 than in any other year on record, the actual abundance of larvae, as measured by a transport abundance index, was the highest ever recorded (23,200 larvae in 1998 compared to an average of 13,4001arvae during the drift periods from 1991 through 1996; Kevin Bestgen, Larval Fish Lab, personal communication). This scenario was caused by the unusually high flows that existed late into the summer of 1498. Subadult and Adult Entrainment Few fish were found stranded in the Green River Canal during the occasions when it was 5