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abundance and CPUE indices tracked each other closely so we present mostly relative abundance data here. RESULTS AND DISCUSSION Effects of~Flaming Gorge Dam on Green River discharge and temperature patterns, Lodore Canyon.-We present extensive information on historical and present-day streamflow and temperature patterns of the Green River because we believe they are a significant influence on fish distribution and abundance patterns for the associated time period. Further, detailed understanding of dam operations may also allow predictions to be made about effects of flow and temperature regimes to the extent that such may be useful to manage distribution and abundance of fishes. Summaries are also available in Bestgen and Crist (2000) and Bestgen et al. (2006), but are brought up to date and presented here for the convenience of the reader. Four major dam-related events affected physical habitat and the fish community of the upper Green River: dam installation in 1962, penstock modification in 1978, flow re-regulation beginning in 1992, and higher peak flows, lower base flows, and drought events since 1997. Prior to construction of Flaming Gorge Dam, discharge patterns of the Green River exhibited high spring peaks followed by lower, stable base flows in other seasons, particularly winter (Fig. 2). Water temperature ranged from a low of 0°C in winter to over 22°C in summer (Fig. 3) and turbidity increased seasonally from inputs of fine inorganic silts (Vanicek et al. 1970). Immediate dam effects included inundation of riverine habitat in the reservoir zone. Downstream, naturally variable and relatively high spring discharge maxima were reduced (Fig. 4). Power plant operations increased base flow levels and daily discharge fluctuations. Naturally turbid water was cleared when virtually all sediment was trapped behind the dam. Water drawn from the hypolimnion of the reservoir reduced temperature of summer releases to about 6°C after reservoir filling was completed in 1967. Downstream warming occurred but mean monthly summer water temperatures reached a maximum of about 14°C in the post-dam period in Lodore 14