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The congregation of radio-tagged adult pikeminnow in the same location for two consecutive years during the estimated spawning period plus the collection of larvae 4 miles downstream at Bridgeport suggests that Colorado pi keminnow were spawning there. Therefore, the reach between Escalante Bridge and Bridgeport is believed to be an important spawning area for this species. Former capture and radiotelemetry data indicate that adult Colorado pikeminnow, uthe 2.3-mile reach of the Lower Gunnison River and plunge pool immediately downstream of the Redlands Dam. Adult Colorado pikeminnow have possibly used the Lower Gunnison River downstream from Redlands Dam as a spawning site in some years (McAda and Kaeding 1991; Burdick 1997). Between 6 and 22 July 1994, this reach was sampled intensively and 20 adult Colorado pikeminnow were captured (Burdick 1997). Although none of these pikeminnow handled had expressible gametes, the high number of fish observed and collected during this time suggested spawning or post-spawning activity. Since then, this reach has not been sampled as intensively during the presumed summer spawning period, and it is unknown whether other pikeminnow congregations have similarly occurred. METHODOLOGY Fish Trap From 1996 to 2000 the trapping facility at the upstream end of the passageway was monitored Monday through Friday between April and early-November. The fish trap and passageway were not operated between early-November and March in each of the five years of initial operation. On weekdays, all of the larger- bodied (> 100 mm) fish collected in the fish trap were sorted and counted by species. On the weekends, the trap was checked only for listed fishes, and for the most part, fish were not sorted or counted. The trapping facility allowed researchers to assess the use of the passageway by all fish species. All fishes, except for three of the smaller nonnative cyprinid species (fathead minnow, sand shiner, and red shiner) that were collected were sorted, examined, and counted. No distinction was made between juvenile, sub-adult, or adult fish when fish were sorted and counted. Speckled dace found in the fish trap were counted, although it was recognized that they were able to freely pass through the spacings between the conduits and trash grates and therefore could move both up- and downstream through the passageway uninhibited. Native fishes and salmonids were returned to the river upstream of the dam. In 1996 only, all nonnative fishes (except salmonids) were flushed downstream from the diversion dam via an underground PVC pipe. In all following years, all nonnatives (except salmonids) were removed. 12