A popular trout fishery in the Clinch River below Norris Dam, Tennessee, is maintained by an extensive stocking program. However, survival and return rates of rainbow trout Oncorhynchus mykiss stocked as catchables are low. Twenty rainbow trout (mean total length [TL] ϭ 307 mm) that had resided in the tailwater at least 5 months were collected from the river and implanted with radio transmitters in June 1998. Similarly sized rainbow trout were implanted with radio transmitters at a hatchery and stocked into the Clinch River on 8 July 1998 (N ϭ 19; mean TL ϭ 304 mm) and 16 September 1998 (N ϭ 11; mean TL ϭ 311 mm). The stocked rainbow trout dispersed rapidly and nearly all (93%) of those fish died quickly or emigrated from the tailrace. Resident fish were significantly less active than stocked fish, and they persisted significantly longer (Kruskal-Wallis tests, P ϭ 0.0001). Poor return rates and survival of rainbow trout stocked as catchables were attributed to their rapid, long-range movements and high levels of activity. Such behaviors are energetically inefficient and probably rendered them more vulnerable to predation.

Mortality and physiological responses of adult striped bass Morone saxatilis angled from Lake Murray, South Carolina, and held in live-release tubes were evaluated during the spring and summer of 2003. To estimate mortality, we attached external ultrasonic transmitters to 59 striped bass (mean total length [TL] ϭ 585 mm). Striped bass were caught with angling gear, tagged, and immediately released or held in live-release tubes for 2, 4, or 6 h prior to release. No mortality of striped bass was observed during spring. Overall mortality during summer was 83%. Mortality of summer-caught striped bass was not related to tube residence time, fish TL, depth of capture, or surface water temperature. To characterize physiological stress, we measured the plasma cortisol, glucose, lactate, and osmolality levels of 62 additional striped bass (mean TL ϭ 563 mm) that were angled and immediately released or angled and held in live-release tubes. Plasma cortisol, glucose, lactate, and osmolality were positively related to tube residence time. When the hematological characteristics were considered only in relation to tube residence time, responses indicative of physiological stress continued for about 150 min, after which blood chemistry began to return to normal. Live-release tubes appear to be useful for keeping striped bass alive when they are angled from cool water, but they are not effective for striped bass angled from warm water. The high summer mortality of striped bass suggests a need for restrictive fishing regulations during the summer for the Lake Murray striped bass fishery.

We used radiotelemetry to monitor the seasonal movements of trophy‐size brown trout Salmo trutta in the Clinch River below Norris Dam, Tennessee, to determine whether establishing a special‐regulation reach to reduce fishing mortality was a viable management option. Fifteen brown trout (size range, 430–573 mm total length) collected from the river were implanted with radio transmitters between November 1997 and May 1998. Forty‐seven percent of these fish died or expelled their transmitters within 50 d postsurgery. The range of movement for surviving brown trout was significantly larger in fall (geometric mean range = 5,111 m) than in any other season. Four brown trout that were monitored for more than 1 year exhibited a limited range of movement (<2 km) during the winter, spring, and summer, but they made extensive movements (>5 km) during the fall season, presumably to spawn. Brown trout also moved more during the fall than in any other season. Harvest restrictions applied to a specific reach of the Clinch River would reduce the exploitation of brown trout in that reach for most of the year but not during the fall, when many fish undertake extensive spawning migrations.

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