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Below the Cmryon This reach is comprised of a canyon bound stretch, a transition area as the river leaves the confines of Westwater, and as area of broad floodplain. As with the reach above the canyon backwaters were sampled most frequently (54.03%), but habitat diversity was greater below the canyon (Table 6). Other commonly sampled habitat types were embayments (7.6%), shorelines (12.5%), and the flooded mouth of Cottonwood Wash (16.2%) at RM 112.2. The sampling program yielded a good estimate of availability for all habitat types, again with the exception of shorelines which were likelyunder-represented. The Chi square analysis for presence of YOY chubs by habitat type indicated significant heterogeneity stemming from YOY chub selection for backwaters and flooded trib mouths and a negative selection for embcryments and shorelines (Table 7). However, overall study catch rates of 0.05 YOY chubs /meter in backwaters, 0.06 along shorelines, .017 in the embayments, and 0.02 in the flooded trib mouths indicate they were scarce throughout. This habitat use is likely indicative of the shift in Gila species abundance from roundtail /humpback community in the canyon upstream to a sparse, mono-specific population of roundtail chubs in this section. Sympatric Species Four other native species were collected throughout the course of the study none of which were as numerous as YOY Gila spp. In decreasing order of abundance they were: speckled dace, bluehead sucker, flannelmouth sucker and Colorado squawfish (refer to Appendix Table 3).~~ Only 12 YOY Colorado squawfish were collected; six upstream of the canyoq five within Westwater, and one below. The study site was likely too close to spawning areas to harbor significant ~; members of YOY squawfish.Catch rates of speckled dace and bluehead sucker were positively correlated withxhe peak flow at the State Line gage (Table 8) as well as the cumulative flow metrics: pre-peak flow and post-peak flow. Non-native cyprinids dominated the low velocity habitat collections in each of the three study areas. Throughout the project fathead minnows were the most numerous, followed in decreasing order of abundance by red shiners and sand shiners. Catch rates varied amongst the three study areas (Figure 8) . Canyon catch rates were usually lower than those upstream and downstream , with the exception of sand shiners. This general decrease in density ofnon-native cyprinids within Westwater Canyon is due to the lack of their preferred habitat. Concurrent nursery habitat investigations on the Green and Colorado Rivers (Trammel et al. 1997) indicate a DRAFT 21