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DISCUSSION We evaluated aspects of the protocol offered by Stanford et al. (1996) for restoration of biota in regulated rivers. The chronology of river regulation events and associated biotic evaluations that occurred in the regulated reach of the Green River upstream of the Yampa River from 1962 to 1996 offered an opportunity to determine the effectiveness of thermal enhancement and discharge re-regulation to restore native fishes. Temperature modification in 1978 benefitted growth of trout in the tailwater fishery and had an immediate effect on the downstream native fish community because reproduction by most species was restored. Restoration of more natural flow patterns and associated thermal enhancement in 1992 had a more subtle effect but may be responsible for increased abundance of endangered Colorado pikeminnow in the regulated reach, increased abundance ofnon-indigenous warm water fishes, and reduced abundance of cold water fishes since 1980. Below, we discuss the implications of our results for the river restoration protocol in general and offer specific suggestions for further restoration of physical habitat and the native fish community of the Green River downstream of Flaming Gorge Dam. Effects of Flaming Gorge Dam on Green River discharge and temperature patterns.- The major event that affected natural temperature and discharge regimes and the sediment budget in the Green River system was closure and operation of Flaming Gorge Dam in 1962. Once a summer-warm system where water temperatures exceeded 22°C, post-impoundment hypolimnetic dam releases rarely exceeded 6°C. Normally high spring discharge was eliminated, and the hydrograph was essentially flat. Water released from the dam remained clear in the regulated reach unless tributaries contributed sediment. Temperature modifications implemented in 1978 and flow modifications begun in 1992 have re-created temperature and discharge regimes that more closely resemble historical conditions. Summer releases have been maintained at 13°C since 1978, although water up to 15°C was available in some years. The more naturalized post-1992 hydrograph called for spring releases to be increased to about 35 % of pre-dam peaks and lower, and for more stable summer 26