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short periods during low flow. However, if low flows persist for several continuous days, water quality could deteriorate possibly causing mortality. Current Sampling. Sampling of the plunge pool and 2.2-mile reach was conducted bi-weekly April through September, and monthly in March, October, and November in 1994. In 1995, the same areas were sampled bi-weekly May through September and monthly in April, October, and November. Similar effort was expended sampling both the plunge pool and downstream 2.2-mile reach in 1994 and 1995. A total of 22.02 hours of electrofishing was expended in 1994 and 1995. In 1994, 3.57 h of effort was expended electrofishing in the plunge pool; in 1995, 3.18 h. In 1994, 7.01 h were expended sampling the 2.2-mile reach; in 1995, 8.26 h. A total of 40 sub-adult and adult Colorado squawfish was captured in 1994; another 10 were sighted but not netted (Table 1; Appendix; Table C.1.). In 1995, only 19 Colorado squawfish were collected and four were positively sighted (Table 2; Appendix; Table C.1.). A total of twenty-three of these 59 fish had been captured previously--14 in 1994 and nine in 1995. Seven fish had been recaptured twice and one had been recaptured three times (Appendix; Table C.2.). No coded- nose-wire tags were detected in any Colorado squawfish captured during this study. The plunge pool and a 0.2-mile section (RM 2.9-2.7) immediately downstream of the plunge pool were high-use areas for adult Colorado squawfish during both years. Twenty-one of the 40 Colorado squawfish in 1994 were captured in the plunge pool. In 1995, five of the 19 fish were captured in the plunge pool. Fifty-one of the 59 squawfish (86X) collected during the 2-year study were captured in the plunge pool or the 0.2-mile section immediately downstream (Tables 1 and 2; Figure 2). Between 6 and 22 July 1994, a total of 20 adult Colorado squawfish were found in this 0.3-mile area. At the same time, an aggregation of Colorado squawfish was observed in the Colorado River (RM 169). Although none of the fish handled in the Lower Gunnison River had expressible gametes, the high number of fish observed during this time suggest spawning or post-spawning activity. The highest CPUE for sub-adult and adult Colorado squawfi sh in the 2.3-mile reach during 1994 and 1995 was in July (34 fish; 5.56 F/h), followed by June (8 fish; 1.68 F/h), and August (7 fish; 1.52 F/h; Appendix; Table D.1.). Sixty-two of the 73 fish captured and sighted were collected during these three months (Appendix; Table C.3.). Other Common Fishes In addition to Colorado squawfish, four other native fishes, nine nonnative fishes, and three sucker hybrid fishes were collected (Appendix; Table A.1.). A total of 6,757 fish was captured, 2,540 from the plunge pool and 4,212 from the reach (Appendix; Tables A.2. and A.3.) Flannelmouth sucker were the most common species (33.9X), followed by bluehead sucker (31.9X), common carp (13.4X), and roundtail chub (12.6X). Only one adult northern pike was collected (PIT-tag No. 1FY7D162F). Eighty-five adult channel catfish were captured, which comprised only 1.3% of the catch. 13