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upstream of the Redlands Diversion Dam fell back over the diversion dam sometime following their release. One pikeminnow that ascended the fish ladder in 1997 and was released upstream of the diversion dam, moved downstream over the dam sometime following its release because it was recaptured in a trap net at Gardner Pond (RM 174.4) in the 15-mile reach of the Upper Colorado River 9 months later in May 1998 (personal communication, this author). Two other pikeminnow that ascended the passageway in August 1998 were recaptured downstream in the 18-mile reach of the Upper Colorado River near WWWA about 10 months later. Two other pikeminnow that passed through the passageway in August 1998 were recaptured downstream in May 2000, one in WWWA and the other in the 15-mile reach at RM 175.5. One other pikeminnow that ascended the passageway in August 1997 was recaptured downstream 9 months later in Professor Valley at RM 81.6. Two of the fish captured downstream in the Lower Gunnison River below the Redlands Dam, radiotagged, translocated, and released upstream of the dam in 1998 subsequently fell back over the dam. Two of the pikeminnow captured in the fish trap in 1999, radiotagged, and released upstream of the diversion dam returned downstream over the diversion dam following release. Further discussion of the movement of these radio-tagged fish is provided in a following section (Radiotelemetry: Movement and Dispersal). River Sampling Colorado pikeminnow Three Colorado pikeminnow that ascended the passageway were later recaptured upstream of the Redlands Dam in the Gunnison River with electrofishing. One fish, caught in the fish trap on 2 July 1998, was recaptured with electrofishing on 5 August 30 miles upstream. This documented the farthest upstream movement by a non-radio-tagged Colorado pikeminnow that ascended the passageway at Redlands. A second fish that used the passageway 17 July 1998 was caught upstream at RM 8.2 on 16 September 1999. This same fish was recaptured upstream of the diversion dam on 3 August 2000 at RM 25.3. During the late-July/early-August and mid-October electrofishing trips between 1997 and 2000, other pikeminnow were captured that had not passed through the Redlands passageway. The capture of these pikeminnow provided some additional information on the long-term residency of pikeminnow translocated from the Lower Gunnison River and released upstream of the Redlands Diversion Dam and resident pikeminnow captured upstream of the diversion dam during earlier FWS studies (Burdick 1995). A large female pikeminnow (TL=913 mm; weight=8,200 g) was caught in early-August 1997. Another large pikeminnow was sighted but not captured in early-August 1998 and again in early-August 2000 at RM 32.7. The 36