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trap of the Redlands Dam passageway. Streamflow records for the 2.3-mile reach of the Gunnison River immediately downstream from the Redlands Diversion Dam were retrieved from a streamflow gage located within the reach. The days when Colorado pikeminnow were collected in the fish trap were superimposed on the discharge that corresponded for that date. RESULTS AND DISCUSSION Fish Trap General The passageway became operational on 24 June 1996. Construction delays prevented the facility from opening earlier in 1996. It was winterized 25 October 1996. Operational dates of the passageway in following years were: 1997 (27 March to 24 October); 1998 (16 March to 28 October): 1999 (8 March to 13 October); and 2000 (20 March to 25 October). Between 1996 and 2000, 43,123 fish comprising 19 different fish species (6 native and 13 nonnative) and three catostomid hybrids were collected and counted (Appendix; Table A.1.). Three additional nonnative species (red shiner, sand shiner, and fathead minnow) were encountered but not enumerated. Fish captures were highest in 1997 (12,233) for both native (11,547) and nonnative fishes (686), followed by 1996 (8,375), 1999 (8,264), 1998 (7,589), and 2000 (6,662)(Table 1). For the five years reported, the highest flow volume (March- October: 2,367,600 acre-feet) and highest runoff peak (12,000 cfs on 26 May) for the Gunnison River at the Whitewater gage occurred in 1997 (Figure 3). This was also the year of highest fish captures in the fish trap. Native fishes consistently comprised about 93% of the total fish catch for each of the five years (Table 1; Figure 4). Generally, fish trap captures steadily increased in April, May, and June, peaked in July and rapidly declined in August, September, and October (Figure 4), although total fish trap captures varied among months and among the five years of operation (Table 2). For the five years combined, the highest fish use occurred in July and June (10,503 and 8,971, respectively) followed by May (8,228), April (5,593), August (5,002), September (2,213), March (1,949), and October (664)(Table 2). Monthly totals of native and nonnative fishes captured in the fish trap for each of the five years are provided in Appendix; Figure D.1. The most numerous fish collected in the fish trap was the bluehead sucker. They accounted for 45.2, 41.1, 55.4, 54.3, and 67.5% of all fishes collected from 18