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exceeded the average historical condition (1946 to 1962) and preceded timing of the peak by just . a few days (Fig. 9). Base flows in the 2002 to 2004 period matched the historical average - pattern reasonably closely. Temperatures in Whirlpool Canyon (Mitten Park station, just upstream of Whirlpool Canyon), in the 1992 to 1996 and 1997 to 2004 periods, were relatively similar (Fig. 10). The primary difference was a period from mid-May to mid-July, when water temperatures were up to i 4°C cooler in the 1992 to 1996 period compared to 1997 to 2004. This was due to relatively high and cold flows observed in 1993 and 1995. Water temperatures during study years 2002 to - 2004 were similar to, or higher than, average conditions observed for the 1997 to 2004 period (Fig. 11). - Thus, three actions subsequent to dam closure in 1962 have incrementally modified flows and temperatures in the Green River upstream and downstream of the Yampa River to a state - that more closely resembles historical, unregulated conditions. The flow and thermal regimes observed in 2002 to 2004 likely will reflect those that would be realized in low or moderately- - low flow years, under new Flaming Gorge Dam flow and temperature recommendations (Muth et al. 2000). Therefore, studies conducted in the three years from 2002 to 2004 offered an - opportunity to assess fish community response to flows that were at the lower end of the recommendations spectrum. A more complete assessment of fish community response will be - possible only with additional years of sampling conducted in average, moderately-high, or high flow years. - During 2002 to 2004, warmer temperatures in Lodore Canyon resulted in minimal water temperature differences in the Green River upstream of the Yampa River and the Yampa River, - which was a goal of flow and temperature recommendations of Muth et al. (2000). Minimizing temperature differences may reduce the likelihood of temperature shock when Colorado - pikeminnow larvae are carried from warm Yampa River flows into the colder Green River (Berry 1988, Tyus 1991). This problem may be more pronounced when Yampa River flows are - very low and warm and flows in the regulated Green River are higher and colder. 18