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EXECUTIVE SUMMARY STUDY GOAL The 2.3-mile reach of the Lower Gunnison River between the Redlands Di versi on Dam and the confl uence wi th the Col orado Ri ver i s i mportant habi tat for Colorado squawfish and razorback sucker and is designated critical habitat for these two fishes. The purpose of this study was to recommend a minimum streamflow for passage of sub-adult and adult Colorado squawfish and razorback sucker during low-flows in this reach. FIFTY-NINE SUB'-.ADULT AND ADULT COLORADO SQUAWFISH WERE CAPTURED THE HIGHEST CATCH RATES WERE IN JUNE, JULY, AND AUGUST A total of 59 sub-adult and adult Colorado squawfish were captured in the 2.3-mile reach between 30 March 1994 and 7 November 1995. A total of 40 sub- adult and adult Colorado squawfi sh were captured in 1994; another 10 were sighted but not netted. In 1995, 19 Colorado squawfish were collected and four were positively sighted. Twenty-three of these 59 fish had been captured previously. Seven fish had been recaptured twice and one had been recaptured three times. The plunge pool immediately downstream of the Redlands Diversion Dam and a 0.2-mile section (river mile 2.9-2.7) immediately downstream of the plunge pool were high-use areas for adult Colorado squawfish during both years. In late-July 1994, 20 adult Colorado squawfish were found in the reach. The highest CPUE for sub-adult and adult Colorado squawfish 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). Sixty-two of the 73 fish captured and sighted were collected during these three months. The high number of adult Colorado squawfish found in the reach during late-July and early-August 1994 indicates that this reach provides sufficient seasonal habitat for "residency" at 300 cfs and also suggests that this reach is important as a spawning or post-spawning feeding area in addition as a passage corridor. xv