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i rates. Experimental razorback suckers slowed their movements to 1.1 km/day after 15 days and remained similarly mobile (1.2 km) through day 58. Control fish were more than twice as mobile 15 to 29 days after release than the experimental fish, but reduced their overall movements to a much lower rate (0.37 km) than the experimental fish by the end of the study. The reason that the experimental suckers were more mobile during the 30 to 58 day period was in part due to fish 15E traveling upstream toward the release site. The difference in the daily movement rates (km/day) between the experimental and control fish during the 15 to 29 day period becomes more profound when viewed in conjunction with the direction of travel of each fish (Figure 6C). For the purposes of addressing the direction of travel of a fish, the movement rates (km/day) have been defined as positive if fish are swimming upstream and negative if a fish is traveling downstream. Razorback sucker average "directed" movements per day (+/- km/day) became significantly less negative over time (p = 0.05) and varied significantly between treatments (p = 0.042). As seen in Figure 7C, control fish required more than 30 days to reduce their downstream-directed movements, whereas experimental fish reduced their downstream directed movements after 15 days. C DIS USSION Dispersal Patterns Razorback sucker movements within the Millard Bottom acclimation backwater varied between individuals and changed in pattern over time. Three of the 15 fish were observed to roam nearly the entire length (~1/3 km) of the backwater within 10 minutes, while others appeared to roam within limited sections of the backwater or not move at all. Patterns in fish movement within this backwater were not correlated with condition factor, nor were these patterns able to predict post-release movement patterns. However, razorback suckers altered their movement patterns within the backwater over time. Fewer suckers (20%, n = 45 contacts) were observed to be positioned near the blocking net at the mouth of the backwater during the first day, but by the second day of confinement within the backwater the percentage rose to 43%(n = 37). Only 3 of the 13 suckers (2 escaped) exited the cove within 2 hours of removing the blocking net. The three fish departed singly and moved downstream and out of the ~1/2-km directional receiver range within 7 to 26 minutes. Seven of the ten remaining razorback suckers were observed to approach the area where the blocking net had previously been only to turn around and swim back into the backwater. These fish either simply anticipated that the net would be in its previous location since the turbidity of the water prevented visual recognition of the net except at very close range, or they were not yet ready or willing to enter the river. The duration of time required for the last razorback 15 1