In August 1993, Tims Ford Dam was retrofitted with an aeration system designed to increase dissolved oxygen to 6.0 mg/L, and a minimum flow requirement of 1.6 cms was implemented. Presently, this tailwater on the Elk River in southern Tennessee annually receives 60,000 catchable (> 200 mm total length) and 35,000 fingerling rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta. The number of catchable trout currently stocked represents a 100% increase over previous years. In November 1994, 5,000 subcatchable rainbow trout were microtagged and stocked. In 1995, cohorts (N = 4,000) of catchable rainbow trout were microtagged and stocked in April, June, and September. In April 1995, one cohort of catchable brown trout was microtagged and stocked. Survival was investigated by electrofishing and conducting a roving creel survey. Growth, condition, and prey utilization were also investigated for each tagged cohort. Electrofishing catch per unit effort (CPUE) of rainbow trout stocked in November declined linearly (r-sq = 0.97), and CPUE approached zero within 150 days. The decline in CPUE for brown trout was exponential (r-sq = 0.92), and approached zero within 200 days. Decline in CPUE for rainbow trout stocked in April and June was hyperbolic (r-sq > 0.90), and approached zero within 50-60 days. The CPUE of rainbow trout stocked in September also declined exponentially (r-sq = 0.99) and also approached zero within 60 days. Few individuals from any cohort were present in the creel after 60 days post-stocking. Returns to the creel were less than 25% for all cohorts and were less than harvest rates before the dam was retrofitted. The diet of trout in the Tims Ford tailwater appeared inadequate to enable substantial growth or maintenance of body condition. Poor survival, slow growth, loss of condition, and low returns to the creel may be the consequences of stocking too many trout in a system that cannot support them.

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