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confluence with the Colorado River. It was presumed these fish were not year-long inhabitants of the Dolores River, but ralher temporary migrants from the Colorado River; however, it was also concluded the Dolores River provided suitable habitat for the reintroduction of this species and the razorback sucker CXvrauchen texanus). Perhaps most significantly, thirteen potential spawning sites for the Colorado squawfish were identified in the Dolores River. Over the two year collection period, native fishes comprised 19% of all fish collected, a relatively high percentage compared to many other rivers in the Upper Colorado River Basin. In addition, evidence of natural reproduction by all of the five unprotected native fish species listed above was found. Roundtail chub, a Category II listed species under the Endangered Species Act, was the fifth most common fish collected of the twellty species collected during the course of the study. Evidence of roundtail chub reproduction was found in the CDOW sUl:veys of 1990-1994 at the pennanent sampling station below the Dove Creek Pumps. Young-of- the-year round tail chubs were collected in relatively large numbers in both 1991 and 1992. Predation from non- native fishes was not thought to be a significant limiting factor in the system. The recommeadations of this study included the avoidance of low flow releases from. McPhee Dam especially during summertime periods. Further, it was recommended that 50 cfs be adopted as a minimum base flow. Most significantly, it was concluded operation of McPhee Dam has the potential for either adversely or beneficially impacting native fish populations. Timing, duration and magnitude of spills coupled with maintaining adequate base flows from McPhee Dam were identified as important in maintaining the downstream native fishery. 2. ENVIRONMENTAL CONSEQUENCES TROUT FISHERY ALTERNATIVES 1, 2 and 3 - Implementation of the managed pool alternatives, would result in creation of habitat suitable of supporting a good trout fishery downstream of McPhee Dam. Alternative 2 would be the preferred alternative from a biological perspective. Under this alternative, the !ish and wildlife pool would not share water shortages with other project users, thus avoiding extreme low flow periods. Under these three alternatives, water released during spills would not be subtracted from the fish and wildlife pool; this amount of water would be available for release through the remainder of the water year. Also. being able to plan for future releases when the extent of the spring runoff is known would increase the precision with which the amounts of water available for the trout fishery during the transition between the critical summer and winter periods could be calculated. In the case of higher runoff years, there may be enough water available to increase the summer and winter minimum flows. ALTERNATIVE 4 (No Action) - The No Action Alternative would result in the periodic loss of much of the trout fishery below the dam during designated flows of 20 and 50 cfs. This alternative is the least desirable. MCPHEE RESERVOIR ALL ALTERNATIVES - Implementation of any of the alternatives would not affect reservoir' fishery habitat to any significant degree. The proposed action would have no effect on management of spills. NATIVE FISHERY ALTERNATIVES I and 2 - All the pool management alternatives would benefit downstream populations of native fishes since the occurrence of extreme low flows during the summer would be eliminated except during periods of shared shortages under alternatives I and 3. ALTERNATIVE 3 . With less waler available in the pool, a scenario may be created in which high 2S