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The average sizes of Colorado pikeminnow (Figure 5) and channel catfish (Figure 6) captured upstream from Tusher Wash Diversion Dam were larger than the average sizes of these species caught downstream from the dam (Table 8). The average size of flannelmouth suckers caught upstream from the dam was smaller than the average size of this species caught below the dam (Figure 7), but this difference was not significant (Table 8). The average size of bluehead suckers caught upstream from the dam was nearly identical to the average size of those individuals caught downstream from the dam (Figure 8; Table 8). Common carp caught upstream of the dam were slightly larger than those found downstream of the dam (Figure 9), but this- difference was not significant (Table 8). All individuals from the genus Gila were captured upstream of the dam and most of these individuals were too small to be sexually mature (Table 5). Very few speckled dace, black bullhead, fathead minnow (Pimephales promelas), green sunfish, red shiner, sand shiner (Notropis stramineus) or walleye were captured using electrofishing gear, so length-frequency histograms are not presented for these species. However, no significant differences by location in average size were noted for any of these species (Table 8). Subadult Telemetry One radio-tagged Colorado pikeminnow was never relocated after release (40.791). Another pikeminnow (40.050) moved downstream after release. After one month this fish was located in a shallow, sandy area and it remained in that location for the remainder of the study. Based on the lack of movement and the habitat conditions found in this area, it was assumed that this fish had died or lost its tag. An attempt to recover this radio from the river was unsuccessful. The other five radio-tagged pikeminnow also moved downstream soon after being released. These movements ranged from less than one mile (40.751) to over 58 miles (40.781; Table 9). However, all of these fish eventually found areas that they appeared to inhabit for extended periods of time. All of these fish were alive when the last radio contact was made, so these areas represented occupied habitat rather than the location of a dead fish or a lost transmitter. Radio-tagged flannelmouth suckers did not move as far as radio-tagged Colorado pikeminnow. Flannelmouth suckers generally stayed near their release point. The longest distance a flannelmouth sucker moved downstream was only 6.9 miles (Radio 40.841). However, three flannelmouth suckers (Radios 40.800, 40.771, and 40.760) did move upstream past Tusher Wash Diversion Dam during September or early October (Table 10). Two of these fish moved past the dam during a period when discharge ranged from 4,100 to 4,820 cfs, while the other fish moved when the discharge ranged from 3,660 to 4,820 cfs. The average monthly discharge of the Green River is below 4,800 cfs during seven months of the year (Table 1). Most radio-tagged flannelmouth suckers, like radio-tagged Colorado pikeminnow, found small areas that were inhabited for extended periods of time. Bluehead suckers tended to move farther than flannelmouth suckers, but not as far as Colorado pikeminnow. The longest movement documented for a bluehead sucker was 21.9 miles (40.060). However, radio contact was not made after two weeks for three of the five tagged fish. The fish that made the longest movement was also the fish that was tracked over the longest period of time. None of the radio-tagged bluehead suckers were found to have moved upstream past Tusher Wash Diversion Dam (Table 11). 7