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2. Continue selective passage and operate the fish trap to remove all nonnative fishes. Rationale: Nonnative fishes have become established in rivers of the Upper Colorado River Basin, and certain species have been implicated as contributing to reductions in the distribution of native fishes primarily through predation and competition (e.g., Hawkins and Nesler 1991; Lentsch et al. 1996; Tyus and Saunders 1996). Controlling problematic nonnative fishes is necessary for recovery of endangered Colorado pikeminnow and razorback sucker in the Upper Colorado and Gunnison rivers. Tyus and Saunders (1996) identified nonnative channel catfish as the principal predator and competitor affecting humpback chub populations in the Upper Colorado River Basin, and Tyus (1998) suggested that negative interactions with channel catfish were major factors in the decline of humpback chub in Yampa Canyon. There are various accounts of the piscivorous Colorado pikeminnow "choking" on spines of channel catfish (McAda 1983; Pimental et al. 1985; Ryden and Smith 2001). The passageway should continue to be operated as a non-"run-of-the- river" facility. That is, fish entering the fish trap at the upper end of the passageway should not be allowed to pass freely upstream and should be sorted as they have been over the past 5 years. Operating the facility in this manner will preclude the invasion and establishment of nonnative fishes such as channel catfish, which are virtually absent upstream of Redlands, thus preserving the main channel fish community which is predominantly comprised (79%) of large-bodied native fishes (flannelmouth sucker, bluehead sucker, and roundtail chub; Burdick 1995). All nonnative fishes moving through the fish passageway should be excluded from moving upstream by removing them from the fish trap. These include all centrarchid species, esocids, nonnative cyprinids, ictalurids, and nonnative suckers that hybridize with native suckers (e. g., white, longnose). Seventy-two percent of all nonnatives that used the passageway from 1996-2000 did so in June, July, and August. 3. Investigate the extent to which sub-adult and adult Colorado pikeminnow use the tailrace between the Redlands Power Plant and Colorado River. The use of the tailrace by Colorado pikeminnow should be determined, especially during the period that coincides with pikeminnow use of the Redlands fishway. About 750-850 cfs of Gunnison River water is diverted at the Redlands Diversion Dam on the Gunnison River into the Redlands canal. Between 750 and 800 cfs of this water is discharged into the tailrace below the Redlands Power Plant. This 50