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and average was 5.2 miles. The similarity between average total and net movement for the two winters (2.3 and 2.1 miles in year 1; 5.2 and 2.9 miles in year 2) indicates little random movement by the fish outside of their immediate habitat. We conclude from this analysis that the majority of adult razorback suckers in the Green River overwinter within a 1 to 3-mile reach of river. Local movement by these overwintering fish was generally restricted to a specific habitat with little net movement. Under nonfluctuating, ice-free flows, 3 overwintering adult razorback suckers in year 1 moved an average of 24.54 m/h, while 8 fish in year 2 moved 30.93 nVh. This movement was usually between favorite spots, which the fish occupied for extended periods of time. This amount of movement is considered normal, and did not differ with habitat types as was seen with Colorado squawfish. We attribute the relatively greater movement during year 2 to lower flow regimes that may have created more marginal conditions in fish habitat. Figure 6 illustrates the local movement of a radiotagged fish monitored in year 1. Razorback sucker OR-3257 occupied three favorite spots, two within the same slow run and one in a nearby slackwater in a sand trough, during a 24-hour period. This fish occupied these spots for periods of 15, 4, and 5 hours. The fish moved a total of 103 m during this time, but ended up only 20 m from its original location. We conclude from these observations that local movement rates of 24 to 31 m/h are normal for overwintering adult razorback suckers. This movement is not continuous, but occurs between favorite spots used by the fish for up to several hours before moving to another spot. Local movement of adult razorback suckers under ice and nonfluctuating flows could not be analyzed because of insufficient sample size. Only 1 radiotagged fish was located in these conditions; movement rate of this fish was 19.71 m/h, in a pattern similar to that of Colorado squawfish. Rahi tai- rlcP No significant differences were found in habitat used by adult Colorado squawfish or razorback suckers among the diurnal, nocturnal, and crepuscular periods. Habitat data were therefore pooled for the respective species. Colorado Squawfish During the first winter of this investigation, the 10 radiotagged Colorado squawfish were observed in four habitat types; runs, slackwaters, eddies, and backwaters. The fish occupied these habitats 43, 39, 12 and 6% of the total observation time, respectively (Figure 7). All of these observations were made during ice-free conditions. The 9 radiotagged fish monitored the second winter, under ice-free conditions, used runs, slackwaters, backwaters, and eddies 64, 29, 5, and 2% of the time, respectively (Figure 7). The same 9 fish monitored under ice- covered conditions during year 2 occupied runs, backwaters, and slackwaters 69, 17, and 14% of the time, respectively. Their use of ice-covered backwaters and relatively shallow areas is believed a behavioral response to surface ice as a cover element that may be associated with feeding. 40