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Several shifts in the fish community were observed as result of the 1993 flows, which would support a peak flow of 25,000 cfs and the preceding recommendation: 1) channel catfish did not successfully reproduce or recruit; both native catostomids appear to have recruited well for the first time since 1989. In addition, the abundance of nonnative cyprinids was negatively correlated with the peak. During-dry years (e.g. 1994) a low peak and summer and late season flows maintained at moderate levels (below 4000 cfs and above 2000 cfs) to provide stable backwater and shoreline habitats appear to benefit Gila spp • Flows observed in 1995 (peak of 29,800 cfs occurring late in the year), did not appear to immediately benefit the native species, nor did they appear to negatively impact channel r-.i catfish. However, incorporating earlier Deso/Gray monitoring data (1989 - 1991) and "~ data collected subsequent to the subject studies (1997 and 1.998) it appears that the periods of high flows (mid-1980' and mid-1990's) tend to benefit the Deso/Gray native fish community. Similar. findings were reported in Westwater Canyon when longterm '~ data were considered there (Chart and Lentsch 1998). _~ There have been direct links made between high flows and the availability of flood plain habitat in the Green River upstream ofDeso/Gray. Those relationships should drive a spring runoff flow recommendation (magnitude and duration) for the Green River. However, based on the information referenced above, those recommendations will likely ~. ' benefit the Deso/Gray fish community as well. Future Work • YOY chub numbers and were highest in Desolation Canyon (above RK 249.4). This may ~~. indicate that spawnng sites were primarily in this reach. Monitoring of spawning locations, and searching for additional sites, in Desolation Canyon should continue. The Three Fords spawning site is important to Colorado pikeminnow. Monitoring and preservation of this site should remain a priority for the lower Green River. A population estimate of spawning pikeminnow would be valuable in measuring recovery. Numbers of endangered fish is highly variable between years and between river reaches. Monitoring for YOY fish should be conducted twice yearly (early August and late September) in both flood plain and canyon bound reaches. The incorporation of a fall monitoring effort in Deso/Gray will be critical if assessing pikeininnow reproductive success in the canyons is warranted by the Recovery Program. • Recent studies have shown that YOY chubs in canyon-bound river reaches do not select for backwater habitats (Valdez and Ryel 1995; Chart and Lentsch 1998). Future -~ monitoring efforts for YOY chubs in Deso/Gray should target a variety of low velocity shoreline habitats. t~ '{ ~,, xxii