The Clinch River below Norris Dam in east Tennessee is stocked annually with about 30,000 harvestable rainbow trout Oncorhynchus mykiss, 150,000 fingerling rainbow trout, and up to 25,000 brown trout Salmo trutta. In 1984, a weir dam was installed to increase wetted perimeter and in 1995, autoventing turbines were installed to increase dissolved oxygen concentrations. Habitat in 20 km of river below the dam was surveyed and mapped utilizing a modified version of the Basinwide Visual Estimation Technique. Spatial and temporal variation in habitat use by trophy (> 375 mm) rainbow trout and brown trout in different reaches of the tailwater were examined by electrofishing 12 fixed transects approximately monthly in 1996. Condition and prey utilization were also investigated. Three distinct reaches were deliniated based on the percentage of shoals present at each electrofishing site. More rainbow trout were collected during the fall at electrofishing sites with abundant shoals, and brown trout were more abundant at these same sites during the spring and summer. Abundance of trophy rainbow trout was highest at downstream electrofishing sites during the summer, but their abundance was similar among all reaches in spring and fall. Trophy brown trout were more abundant in the upper reach during fall, but their abundance was similar among all reaches in spring and summer. The condition of trophy rainbow trout and brown trout varied significantly over time and both species exhibited similar seasonal trends; condition was similar in spring and summer but dropped significantly during the fall (analysis of covariance; P <0.01). Both trophy rainbow trout and brown trout diets varied by season. Trophy rainbow trout consumed proportionally more invertebrates than brown trout in all seasons. No fish were found in the diets of trophy brown trout in the spring; however, percent occurrence of fish in the diet exceeded 40% in the summer and fall. The average size of trout varied seasonally among reaches in the river and was likely affected by differences in the habitat and fishing pressure. Most trophy trout were located in areas of the river bordered by private land with little angler access during the spring and summer; however, during the fall large numbers of trophy trout were sampled above the weir dam near public access points.

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