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1 Four different control fish and two experimental treatment fish were observed to occupy backwater habitat in the Green River below the release site. Fish 1 C was observed in two separate backwaters (Anderson Bottom and at Green River RK 12) and fish 6C was located in Horse Canyon backwater (Green River RK 23.3) on three separate occasions. Backwaters were only utilized by the control fish during the first 2 weeks. Fish 15E was the only sucker observed to still utilize backwater habitat after 2 weeks (July 9, day 20). Fish15E was located in Dead Horse Canyon (Green River RK 31.5 ), which was rapidly becoming dry. This fish did not need rescued, however, because a flash flood carved 15E into the river shortly after day 20. Between the 0 to 14 day period following release, razorback suckers utilized riverine habitats which experienced all available current intensities, but the majority of fish locations were in regions of slow or no current (Table 4). In spite of a high affinity for slow current, many razorback suckers (SE, 10E, 14E, 15E, 2C, SC, 6C, and 7C) moved between regions of slow current (<~1.4 km/hr) and swift current (>~3.8 km/hr). Fish 6E, 8E, 1C, 14C, and 15C were observed to only utilize habitats with slow or no current. Fish 6E, 14C, and 15C were located in near shore regions; 1 C was found in Anderson backwater (Green River RK 49.8) on day 1 and in a shallow backwater at Green River RK 12 on day 7; and 8E was in a slow moving eddy pool at Colorado River RK 342. Sucker 9C was the only fish that utilized solely regions of swift water. Fish 9C was located in different sections of swift water on three separate occasions during these first 15 days. During the period of 15 to 29 days since release, 12 of 15 razorback suckers were found to be in habitats of slow or no current. Fish 11 C, 15C, and SE were positioned in slow current, as well as occupying moderate current (11 C and 15C, ~ 1.4-4.6 km/hr) and swift current (SE). During the final 4 weeks the suckers began to reoccupy habitats with swift current, as well as continuing to utilize slow current regions. Only 7C moved between habitats in different current categories. Fish 7C occupied the very deep, swiftly flowing water in the run adjacent to and upstream from the "Dangerous Rapids Ahead" sign at Colorado River RK 345. As previously mentioned, fish 7C was also observed on one occasion to move 1 out of the channel and move upstream along the northwestern bank approximately 100 m. Razorback suckers initially began to occupy habitats of seemingly every available depth (Table 5). During the first 14 days,. the experimental fish were utilizing chiefly shallow (0-1.2 m) or deep water. Only one fish from the experimental treatment (15E) was located in a habitat of moderate depth (1.2 to 3.0 m). Fish 15E was also found in the shallowest backwater habitats and the deep main channel. The control treatment fish were found in similar proportions in shallow, moderate, and deep habitats. Three control fish (2C, 6C, and 7C) were observed to move between shallow and deep regions of the Green and Colorado Rivers. 13