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water temperatures in most years. Previously, this limitation was observed in lower Lodore Canyon but moved upstream because of elevated temperatures in 2002 to 2004. ? Abundance of several hybrid combinations of suckers was high and increased since 1980 and again since the 1994 to 1996 period. Particularly common were hybrids that had white sucker as one parental type. Occurrence of cool water white suckers and hybrids declined in a downstream direction in Lodore Canyon, presumably in response to warmer water temperatures. ? Trammel net sampling detected a small population of humpback chub in Whirlpool Canyon and a relatively large population of roundtail chub. Hatchery-stocked bonytail were also captured. Trammel net sampling was a useful technique to sample chubs. ? Stocked bonytail were susceptible to predation and infections and survival rates were low based on absence of recaptures of fish more than a few weeks after stocking. ? Drift net sampling failed to detect reproduction by Colorado pikeminnow. Drift sampling revealed important patterns of increased downstream transport rates of fish in response to turbidity events. ? Colorado pikeminnow continued to use Lodore Canyon heavily in summer, based on captures we made and those in a companion study. Ripe male Colorado pikeminnow were detected there in 2001 and 2003, indicating suitable conditions for reproduction. ? More complete evaluation of the response of the fish community to flow and temperature regimes from Flaming Gorge Dam will require additional years of sampling in conditions other than the low and warm summer flows we observed. RECOMMENDATIONS ? Continue removal of predaceous and other non-native fishes from Lodore Canyon. ? Continue to monitor water temperature, flows, and the fish community of the Green River in Browns Park, Lodore and Whirlpool canyons, and Island-Rainbow Park, as outlined. 71