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to collect all fish in 1997, so these data are probably more reflective of the true community composition. Comparisons ofcatch-per-unit-effort for electrofishing data through time and space showed that catch rates of some of the abundant, large-bodied non-native species were variable (Figure 13). However, analysis of variance tests revealed no significant differences in catch rates for native species (Table 4). Catch rates of channel catfish were higher in 1996 than in 1997, and higher in the Canyon area than in the Woodside area, but there was no significant interaction between these two variables. No differences were noted in catch rates of common carp between 1996 and 1997, but more carp were captured in the Woodside area than in the Canyon area. There was no significant interaction between these two variables. No differences were noted in the catch rates of Colorado pikeminnow by location or year, and there was no significant interaction between these variables. Similarly, catch rates of flannelmouth suckers did not differ through space or time, and there was no interaction between these variables. In addition, no significant differences were noted in the catch rate of bluehead suckers through time or space, and there was no interaction between these two variables. Length-frequency histograms of flannehnouth suckers (Figure 14) and bluehead suckers (Figure 15) captured by boat electrofishing demonstrate that many suckers of both species survive to adulthood, and that successful recruitment occurs annually in both populations. Common carp also seem to recruit successfully each year (Figure 16). The size distribution of channel catfish is skewed toward small individuals, with several size classes that are not well represented (Figure 17). Few speckled dace were caught while electrofishing, so little can be determined from examination of the 19971ength-frequency histogram for this species (Figure 18). The average length of native species that were commonly caught with boat electrofishing differed through time and space, but differences in the lengths ofnon-native species were not noted (Figure 19). Chi-square analyses (Table 5) showed that the Woodside section contained significantly more subadult flannelmouth suckers than the Canyon section, and significantly more subadult flannelmouth suckers were present in 1996 than in 1997. The percentage of subadult bluehead suckers did not differ significantly between the Woodside and Canyon sections or between 1996 and 1997. No significant differences were noted between the percentages of subadult catfish in the Woodside and Canyon sections or between 1996 and 1997. However, sample sizes were small for adult channel catfish, so caution should be used when assessing the results of statistical analyses on this species. No significant differences were noted between the percentages of subadult carp in the Woodside and Canyon sections or between 1996 and 1997. Statistically valid comparisons of differences in the percentage of subadult Colorado pikeminnow caught in the Woodside and Canyon sections or between years could not be made due to small sample sizes. This was also true of the other species captured by electrofishing. The catch in trammel nets, like boat electrofishing, contained a high proportion of native species (Table 3). Catch rates for flannelmouth suckers were far greater than rates for any other species (Figure 20). Trammel nets were used frequently in 1996, but the high flow that occurred in 1997 limited their use during the second year of the study. Therefore, valid statistical comparisons of catch rates through time could not be made. However, comparisons between the Woodside and Canyon sections were made for data collected in 1996 (Table 6). These analyses showed that the catch rate of flannehnouth suckers was significantly higher in the Woodside section than in the Canyon section. No significant differences between locations were noted for 9