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samples. The subsequent effect may be that they comprise a smaller portion of a larger sample, but do not actually decline in abundance. However, density and relative abundance trends for 2002 to 2004 data often tracked each other closely, suggesting that relative abundance measures often reflect density as well, and that reductions were real. Continued density difference comparisons will allow us to track such changes more closely. Evaluation of the high flows in 1997 and 1999 was difficult because those events were relatively far removed, on a temporal scale, from our sampling. Those flows no doubt had positive benefit for physical habitat, including channel scouring and reworking, and associated removal of invasive tree species in Lodore Canyon and downstream reaches (Muth et al. 2000). Benefits to biota would be best evaluated in a time frame closely associated with the event. Potential measures of effects of high flows would be sampling of fish in low-velocity areas in summer and autumn such as was done in this study. With such data collected over a relatively long time frame, differences in reproductive success and abundance of native and non-native fishes could be evaluated. Escapement of smallmouth bass from Flaming Gorge Reservoir during spills is a potential downside of high flows, especially if release elevation levels coincide with vertical distribution of fish in the reservoir. The net effect of flow and temperature regimes on the native fish community in this river reach, based on our 2002 to 2004 sampling, was mixed. During this study, we were able to obtain information on the response of the fish community to flow and temperature effects, but only at the lower end of the flow spectrum. Flow and temperature conditions observed in 2002 to 2004 fell within the bounds for recommendations that would be implemented in years with low or moderately low water availability, which happen in only 30% of years. Average, moderately high, and high flow years, which occur the other 70% of the time, were not evaluated because those conditions were not realized during this study period. Additional years of sampling when those flow conditions return are needed to fully assess the effects of pending flow and temperature recommendations for Flaming Gorge Dam on the fish community of the Green River. Because components of the fish community may be changing regardless of changes in flow and temperature conditions, monitoring should be on an annual basis. This would allow for 67