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Backwater availability in July and August was positively correlated with both flow at the time of sampling (RZ = .87) and annual peak flow at the State Line gage (RZ = .86). This relationship held true for sample flows nearing 9000 cfs, but appeared to break down at higher flows when many of the side channels became reconnected to the main channel. Backwater habitats were virtually non existent when this stretch was sampled 07 July 93 and the river was flowing at 13,800 cfs. At extremely high flows, (22 June 95; approx. 40,000 cfs), the only true low velocity habitat was the flooded mouth of Westwater Wash. Westwater Canyon fRK 199.2 - 190.4) In this 8.8 km sub-reach, backwaters were not abundant. Only three or four backwaters formed each year following the high spring flows in this canyon stretch. As was the case in the Above Canyon sub-reach, the backwaters that did form varied minimally from year to year at a given flow. Due to the paucity of low velocity habitats in the canyon proper, shorelines were the most commonly (39.3%) sampled habitat followed by backwaters (29.7%), embayments (20.0%) and others (see Table 6 above). The backwater and embayment sampling effort was representative of actual availability. Conversely, shoreline habitats were less discrete and were even more abundant than the relative abundance values would suggest. The less frequently sampled habitat types (side channel, pools, isolated pool, and flooded tributary mouth) were accurately represented in terms of availability. The multinomial analysis of YOY chub presence /absence by habitat type indicates there was no selection at this level of resolution (p=0.94) (Table 9). YOY chubs were distributed among all habitat types as was expected based on the distribution of sampling effort. Table 9. Multinomial analysis for use of habitats by YOY Gila spp. in the Westwater Canyon sub- reach (Colorado RK 199.2 - 190.4), Utah. Data collected in July and August, 1992, 1994, and 1996 and July -Sept., 1993 and 1995. HABITAT TYPE N= Obs. % of Hab. Type Obs. # of Nabs w/YOY chubs Exp. # of Nabs w/YOY chubs Chi-square factor. BW 28 30.1 16 17.16 0.08 SH 37 39.8 21 22.69 O.13 EMB 18 19.3 13 ] l .00 0.36 PO 1 1.1 0 0.63 0.63 IP 3 3.2 2 1.82 0.02 F1' 4 4.3 3 2.45 0.12 SC 2 2.2 2 1.25 0.44 Overall Chi-square =1.78; p=0.94; df=6 A similar analysis accounting for the densities of YOY chub occupying each habitat type indicates YOY chubs were not uniformly distributed throughout the habitat types (Table 10; Figure 9). YOY chubs were collected in shoreline habitats as was expected, based on the distribution of sampling effort and the total number of YOY chubs collected in Westwater Canyon. There was an apparent selection for embayment habitats. However, young of year chubs did not select for backwaters in Westwater Canyon. 11