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tagged. Fish were placed in cages between 7 June and 2 July, which coincided with historical floodplain inundation in the Green River, and removed after 3 to 4 weeks. When fish were removed from the cages, length, weight, and PIT tag numbers were recorded for each individual fish. Growth rates were computed based on the daily average weight change between the beginning and end of the experiment. Survival was calculated as the number of individuals surviving to the end of the experiment divided by the number stocked. The competition experiment included comparison of growth and survival of both larval and juvenile razorback sucker in the presence and absence of red shiner. The experimental design included three replicates of three treatments for both larval (mean total length = 14.3 mm) and juvenile (mean total length = 25.1 mm) razorback sucker comparisons. Three treatments consisting of 300 razorback sucker larvae only, 600 razorback sucker larvae only, and 300 razorback sucker larvae with 300 red shiner adults (mean total length = 36.1 mm) were evaluated to compare growth and survival of razorback sucker in the presence and absence of red shiners. The red shiners used were the smallest fish available from the Green River at the time of the experiment. Three replicates of each treatment were randomly assigned to cages. The design was selected to determine whether interspecific competition between razorback sucker and red shiner was equal to intraspecific competition. Razorback sucker juveniles were tested with the same design and treatments, but the numbers tested were 100 razorback sucker juveniles only, 200 razorback sucker juveniles only, and 100 razorback sucker with 100 red shiners (mean totallength= 22.6 mm). Razorback sucker were produced at the Ouray Native Fish Facility and were offspring of wild fish captured from the Green River. Red shiners were collected from the Green River during the spring of 1993. The trial with larval razorback sucker was conducted in cages, 0.9 m x 0.9 m x 1.2 m, with 700-micron polypropylene mesh. The experiment with juvenile razorback sucker was conducted in cages of identical size, but with 6 mm mesh. Floating cages were anchored in depths exceeding 1.5 m in the open water area of Old Charley Wash, and fish were transported to the site from the Ouray Native Fish Facility. RESULTS Considerable variation was observed in growth and survival of fish held in wetland and backwater cages during 1991, excluding the fish held in the hatchery. No mortality was observed and growth was negligible in fish in the hatchery (Table 3). Mean growth and survival of razorback sucker in cages was greater in the wetland treatment than the main-channel backwater treatment. Survival in the wetland sites 24