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reaches and species that tolerated warm water, such as sand shiner, red shiner, channel catfish, and smallmouth bass, were more abundant. Flannelmouth sucker, bluehead sucker, and common carp were widespread. The Green River upstream of the Yampa River supported eight native fishes (nine if stocked bonytail is included) in 2002 to 2004, and only Colorado pikeminnow did not reproduce. Native fishes in Lodore Canyon in 2002 to 2004 declined in abundance in electrofishing, seine, and drift net samples compared to those collected in 1994 to 1996. Ten native fishes were collected in the Green River downstream of the Yampa River. Native fishes were numerically dominant in trammel net samples in Whirlpool Canyon; no comparative 1994 to 1996 data were available for that reach. Abundance of non-native fishes in Browns Park and Lodore Canyon in 2002 to 2004 increased since 1994 to 1996 sampling. Increases were throughout the study area and were particularly evident for small-bodied cyprinids, channel catfish, and smallmouth bass in the upper portions of Lodore Canyon. Smallmouth bass reproduction, which was not observed in Lodore Canyon prior to this study, increased through the 2002 to 2004 period and was widespread. Salmonids were temporarily reduced in abundance in 2002, but increased in 2003 and 2004, and were similar in abundance to that observed in 1994 to 1996. Abundance of predaceous fishes in the Green River study area has increased. The distribution and abundance of several warm-water fishes in upper Lodore Canyon may have been restricted by relatively cool water temperatures in upstream reaches in most years. Previously, this limitation was observed in lower Lodore Canyon but moved upstream because of increased summer temperatures in 2002 to 2004. Abundance of several combinations of hybrid 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 vi