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1 1 1 1 t U 1 1 positively correlated with weight (p = 0.02, regression analysis, Figure 4). Appendix 3 summarize aspects of the suckers' movements in conjunction with their condition factors. The condition factors of the experimental and control fish that were observed to either swim upstream or hold position in the river overlapped broadly with the condition factors of the fish that were observed to only move downstream. The 7 razorback suckers that were never contacted following release had similar condition factors to the 23 fish that were located via telemetry. In addition, the condition factors (average K = 0.845, n = 6) of the six razorback suckers that utilized backwater habitats were not significantly different from the condition factors (average K = 0.892, n = 14) of those fish not observed to utilize backwaters (p = 0.22, two-tailed t-test). Individual Habitat Use and the Effects of Condition Factor During the first 2 weeks since release, the razorback suckers distributed themselves throughout many of the available habitat types (Table 3). Many fish moved between multiple habitats during this time period. For example, fish 6C was positioned near shore and moving rapidly downstream at Green River RK 48 on day 1. Fish 6C then entered Horse Canyon backwater (Green River RK 23) by day 7, remained there until at least day 13 as the water level fell to an estimated <60 cm, and then re-entered the main channel sometime before day 22. Fish 2C, 7C, and 3E also moved between habitats during the first 14 days. Fish 2C utilized both near shore and main channel habitat, as well as venturing into Jasper Canyon backwater (Green River RK 15.3) on day 7. Both 7C and 3E were located in near shore, eddy pool, and channel habitats as they continued to move downstream. During the 15 to 29 day period following release, the majority offish now began to generally utilize a single type of habitat. Only two f sh, SE and 8E, were observed to be utilizing two or more habitat types. Fish SE was located near shore at Colorado River km 71.9 on day 19 and then entered the channel and quickly moved downstream to Colorado River RK 4.8 by day 25. Fish 8E was located near shore in a deep run adjacent to the large cottonwood tree at Spanish Bottom (Colorado River RK 342, Green River confluence = RK~348.5). Later, 8E was moved upstream to the large eddy pool in the tailwater of "The Slide" at Colorado River RK 2.4. During the last 4 weeks of the study (days 30 to 58), the majority of razorback suckers were no longer near shore, but rather were split between near shore (five fish) and channel habitat (five fish). At this point, the water level of the Green and Colorado Rivers is sufficiently low to have dried all of the backwaters that have formed at the mouth of ephemeral canyon inflows (Figure 5). Eddy pools were now the least utilized of the available habitats. Only fish 6E and 7C were now observed to be positioned in eddy pools. However, both 6E and 7C were now found in eddy pools only once during this period while being found near shore twice (6E) and in the main channel four times (7C). 12 t