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1 1[~ 1 u 1 1 1 1 1 1 rains on June 17 caused the Green River to rise and create a ~2-m-wide passage azound the western edge of the blocking net. This escape route was less than 50 cm deep and contained a dense stand of juvenile willows. The willows possibly aided in reducing the total number offish that escaped. The blocking net was removed at 0640 on June 19. The departure of the remaining 13 experimental treatment razorback suckers (acclimated fish -referred to as "E" for - experimental treatment) from the now river-accessible Millard backwater was monitored unti10912. The first razorback sucker to leave the backwater was 12E at 0805. This fish headed downstream, was out of the ~1/2-km receiver range in 7 minutes, and was never contacted again. Razorback sucker 14E exited next at 0841 and was followed by sucker SE at 0846. Fish 14E headed downstream, was out of range in 18 minutes, and was never contacted again. Fish SE departed downstream, moved out of range in 26 minutes, and would travel downstream to the Colorado River (54 km distance) and then swim at least 72 km up the Colorado River over the next 20 days. The movements of razorback suckers during the first day following their release were only determined for the control group (non-acclimated fish -referred to as "C" for control treatment) due to logistical difficulties. On June 17, five control fish (1C, 2C, 4C, 6C, and 14C) were located in or near Andersen Bottom (Green River RM 48.9), and the seazch was terminated at Green River RK 47. Fish 1 C, 2C, and 4C were all located within Anderson backwater. Fish 14C was located in the inside bend of the main channel of the Green River opposite Anderson Bottom, and sucker 6C was 1 km down river of Anderson Bottom in the river left portion of the main channel and moving downstream. Only fish 14C was released this same day (June 17, 7.8 hours earlier), whereas the remaining four fish were released the previous day (June 16, 23 hours eazlier). It is inexplicable that the majority of the fish located within 7 km downstream from the release point were released the previous day and not fish released just 7.8 hours prior. Fish 1 C, 2C, and 6C were located in different backwaters further downstream 7 days later. It would appear that control razorback suckers seek and enter backwaters as they move downstream following release. Both the experimental and control razorback suckers initially moved downstream from the release point during the first 2 weeks. After this initial period of downstream movement, a few fish (lE, SE, 8E, 15E, 2C, and 7C) that had reached the confluence of the Green and Colorado Rivers (53.8 km distant) began to swim up the Colorado River (Figures 2A, 2B, and 2C). By day 25, fish 8E was now located 8.8 km up the Colorado River from its confluence with the Green River and was not contacted again. Razorback sucker 1 E moved downstream to the Colorado River and swam 52 km upstream during the first 12 days. By day 54, razorback 1 E had moved down the Colorado River, swam through Cataract Canyon rapids, and was now positioned in Lake 9 I~ L~