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1 During the 15 to 29 day period since release, razorback suckers were not observed to move between habitats of different depths as often as during the first 2 weeks. Only fish SE and 8E were observed to utilize both shallow and deep habitats. Fish SE utilized both near shore and eddy pool habitats while 8E utilized neaz shore and channel habitats. t 1 1 1 [1 1 L During the final 4 weeks of the study (30 to 58 days), razorback suckers utilized predominantly deep-water habitats. Fish 6E was observed utilizing all three depth categories, 15E utilized moderate and deep water habitats, and the remaining f sh (8E, 14E, 2C, 7C, and 11C) were utilizing habitats greater than 3 m deep. Fish lE and 15C were found in >3-m-deep water in Lake Powell. Tables 6, 7, and 8 summarize the condition factors of the fish that were located in each habitat, current, and depth category, respectively, over time. The average condition factors of the fish that frequented the four habitat types during the three time periods ranged from 0.81 to 0.93 and were not dependent upon habitat type (p = 0.610), treatment (p = 0.766), or time (p = 0.404). The average condition factors of the fish that occupied the three current intensities ranged from 0.771 to 0.966 and were not dependent upon current velocity (p = 0.935), treatment (p = 0.072), or time (p = 0.070). However, it appears that fish with large condition factors disproportionately utilized habitats of moderate depth (average K = 0.922) to a greater extent than either shallow habitats (average K = 0.869, p < 0.001 tukey's post-hoc) or deep habitats (average K = 0.874, p = 0.018 tukey's post hoc). Comparison of Treatments: Movement Patterns and Habitat Use The majority of razorback sucker dispersal away from Millard Canyon backwater occurred during the first 2 weeks for both treatment groups (Figure 6A). There was no significant affect of treatment (p = 0.737) or time (p = 0.120) upon the distance fish traveled from the point of release. However, there was a small but steady increase in the distance control fish traveled over time. Control fish dispersed 43, 71, and 81 km for the time periods 1 to 14 day, 15 to 29 days and 30 to 58 days following release. Experimental fish averaged 59 km distance traveled over the first 14 days, this increased to 71.6 km by days 15 to 29, and reduced to 53.6 km by the end of the study. Although differences in dispersal were very similaz, a greater proportion of control razorback suckers traveled downstream upon reaching the Colorado River than did experimental suckers. Ten of 14 control fish entered either Cataract Rapids or Lake Powell by day 58, whereas only 2 of 9 experimental fish were found that far downstream (Appendix 3). The average distance razorback suckers moved per day (as estimated from successive radio contacts) decreased significantly over time (p <0.000), and was not significantly affected by treatment (p = 0.437) (Figure 6B). The average daily movements (km/day) of both the experimental and control fish decreased incrementally over time, but at different 14