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the three points described to characterize the microhabitat occupied by the fish as well as the adjacent associated habitat parameters. Habitat measurements taken at all three points were the same, except for velocity. The point measurement included water velocity at 5 cm off the river bottom, and at two-tenths, six-tenths, and eight-tenths of the water depth. Velocity measurements at one meter on either side of the fish ('in' and 'out') were recorded only at six-tenths of the depth. Velocities were measured using a Marsh-McBirney current meter and a 2 or 4-m wading rod. Where the measurement was taken in a countercurrent (i.e. an eddy) greater than 90 degrees from the main directional flow, velocity was recorded as negative. Substrate was categorized as silt, sand, gravel, cobble, boulder, or bedrock by probing with the hand, foot, or wading rod, depending on water depth. Features providing cover (i.e. large boulders, overhanging banks, sand ridges) at each fish location were also recorded. RESULTS AND DISCUSSION Movement No significant differences were found in movement by adult Colorado squawfish or razorback suckers among the diurnal, nocturnal, and crepuscular periods. Movement data were therefore pooled for the respective species. Colorado Squawfish Long-range movement of overwintering adult Colorado squawfish was not considered extensive during this investigation. In year 1, maximum net movement by a fish was 22.2 miles upstream (Figure 2). Although two other fish moved 13.9 and 13.1 miles downstream, 7 of the 10 radiotagged fish were found less than 3 miles from their initial tracking locations. The average net movement of these 10 fish during year 1 was 5.6 miles. In year 2, one fish moved 25.9 miles downstream from its initial tracking location, but the other 8 radiotagged fish remained within 2 miles of their initial respective locations. The average net movement of these 9 fish was 3.6 miles. Total long-range movement by these fish was not very different from net movement. In year 1, maximum total movement by a fish was 22.8 miles, and average total movement by all 10 fish was 6.0 miles. In year 2, maximum total movement was 25.9 miles, and average was 5.3 miles. The similarity between average total and net movement for the two winters (6.0 and 5.6 miles in year 1; 5.3 and 3.6 miles in year 2) indicates little random movement by the fish in the wintertime, outside of'their immediate habitat. We conclude from this analysis that the majority of adult Colorado squawfish in the Green River probably overwinter within a 2 to 3-mile reach of river. Local movement by Colorado squawfish was generally restricted to a specific habitat usually with little net movement. Under nonfluctuating, ice- free flows, 4 overwintering adult Colorado squawfish in year 1 moved an average of 15.23 rr1h, while 9 fish in year 2 moved 23.03 m/h. This movement was usually between favorite spots, which the fish occupied for extended periods of time. This amount of movement is considered normal, although we hypothesize 34