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Figure 2. Photograph showing placement of the electric trolling motor that directed current through the flow exercise rearing tank. The exercise regimen for 2006 and 2007 started in March and February respectively with an initial velocity of7.5 cmls. This increased in 2.5-cmls intervals each week (7.5,10.0,12.5,15.0,17.5, 20.0,22.5,25.0,27.5, and 30.0 cmls) for 10 weeks and then maintained at 30 cmls for the duration of the tests. The electric motors were turned on at 8 a.m.; flows were measured with a velocity meter and motor speeds adjusted to the scheduled velocities. Fish were subjected to current for eight hours from Monday through Friday and allowed to rest at night and during the weekends. Fish were fed a commercial pellet chow at dusk; tanks were cleaned weekly and fish received preventative chemical treatments for parasites and diseases or when they showed symptoms. Predator Exposure Large predators were captured from the wild and brought into the facility at least one month prior to use. They were placed in large tanks and fed live nongame fish salvaged from local ponds. The 2006 plan was to net and release a large flathead catfish in each of the exercise tanks, allow the flathead catfish to feed for 24 hours, and then remove them. Surviving fish would be used to start the predator/prey trials one week later. However, this approach failed (see Observations section) causing. us to abort that test in the 2006 trials and modify our predator exposure design in :WC)7. Instead of 111001ng. the predators, we moved the prey. Treatment groups consisted of < 12 prey with the anticipation thaI one or two fish would be lost during the exposure process, leaving::::lO prey for the predation experiment. Following a predation event, surviving prey were removed, measured, and combined with other treatment or control fish for the actual predator/prey experiment. 4