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Preliminary results from sampling in 1997 indicated that the adult population densities are increasing likely in response to recent recruitment, which. coincides with a period of moderate to high flows in 1993, 1995 and 1996. Spawning Colorado pikeminnow Anew spawning location for Colorado pikeminnow in Deso/Gray was not found. The Three Fords spawning area was further described to include an 18 km stretch of river extending from RK 256 to 238 with the focus of spawning activity shifting within this area on an annual basis Sympatric Species Trends in the flannehnouth sucker catch rate has followed a similar pattern to-that of the chubs, with relatively high catch rates recorded in 1989 followed by a general decline throughout the canyon through the summer of 1994 sampling trip. In 1995, CPE increased dramatically at all sites with the greatest site CPE recorded at RK 295.7. A length frequency analysis for flannelmouth suckers indicates poor recruitment of juvenile flannelmouth sucker through 1993. Beginning in 1994 and continuing through 1996 population structure appears to have rebounded. Channel catfish were the most abundant species collected from main channel habitats with nets and electrofishing every year of study. Throughout the course of six years of fish community monitoring channel catfish have been nearly twice as abundant as Gila spp. In 1993, channel catfish apparently failed to successfully reproduce, or recruit for the first time since 1989. However, successful catfish recruitment was documented during this project's highest flow year (1995). Channel catfish response to flow in Deso/Gray is unclear. RECOMMENDATIONS Flow levels Definitive flow relationships could not be established as result of these project efforts. However the following observations were made. The two flow years Gila spp. spawned most successfully (1993 and 1994) were extremely different. The Green River peaked at 25,800 cfs in 1993 and at 11,800 cfs in 1994. The breadth of the 1993 peak as measured by average flow days in excess of 6000 cfs was nearly twice as long as in 1994. A moderately abundant cohort of Gila spp: were produced in 1996 - a similar flow year to 1.993; differing in that the breadth of the peak lasted 90 days. Catch rates of YOY Colorado pikeminnow were greatest in 1993 and 1996. During moderate to wet years: peak flows near 25,000 cfs with the breadth of the peak lasting 60 days or more appear to benefit both Gila spp. and Colorado pikeminnow. xxi