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coefficients for the discharge parameters suggested that as discharge increased, water temperature decreased. Overall, water temperature predicted by the lower Browns Park model closely matched observed temperatures during 1992 to 1996 (Figs. 12 to 16) and suggested that the model may be useful for making predictions about effects of different operational scenarios. Model predictions were moderately biased in August and September 1994, when predicted temperatures were 1 to 2°C higher than those observed. Bias maybe due to inability of the model to accurately account for late summer discharge levels from Flaming Gorge Reservoir that were slightly higher than normal. Fluctuations in water temperature such as those associated with an extended cold front in late August 1993 were not predicted accurately because the least squares regression model tended to smooth such extremes. Some recurring patterns were notable for predicted and observed (measured) temperatures. In most years, mean daily water temperature at Lower Browns Park approached or exceeded 20°C in mid- to late-June for one to a few days when discharge was low but then declined thereafter. Declining mid-summer water temperatures were associated with increased Flaming Gorge Dam discharge which began in late June to early August in most years. Increased dam releases in summer were needed to sustain the Green River at downstream Jensen, Utah, at a mean daily target level of 51 m3/s as mandated by the 1992 Biological Opinion on Flaming Gorge Dam. Discharge and temperature patterns in the unregulated Yampa River from 1992 to 1996 and pre-dam Green River differed from the ones observed in the present-day Green River. Discharge levels in the unregulated Yampa River declined throughout the summer; water temperature rose during the same time, peaking in late-July to late-August. Water temperatures were sustained in the 20 to 24°C range for a period of one to several weeks. The reproductive period for Colorado pikeminnow in the unregulated Yampa River began in mid- to late-June in most years and was associated with increasing water temperature in the range of 16 to 22°C and declining discharge. In the regulated Green River in Lodore Canyon, water temperature levels in 24