1. The Caney Fork River is annually stocked with over 100,000 catchable (greater than 200 mm total length) rainbow trout Oncorhynchus mykiss and 17,000 brown trout Salmo trutta. This study examined the fate of trout stocked in 1997 and evaluated the habitat and biomass of overwintering trout in the Caney Fork River. A one-time allotment of 20,000 fingerling brown trout (mean length = 66 mm) was stocked in June 1997, and their contribution to the fishery was also evaluated. Cohorts of trout were microtagged, a roving creel survey was conducted, electrofishing samples were collected, and habitat was mapped using GPS and GIS technology.

2. Fishing pressure in 1997 was negatively correlated to discharge from Center Hill Dam. Fishing pressure over comparable 26-week periods was slightly lower in 1997 (61,853 hours) than in 1995 (74,534 hours), due to much higher flows in 1997. Between early March and late October 1997 (32 weeks), fishing pressure was nearly 66,000 hours and represented about 21,300 trips. Anglers harvested 1.2 trout per trip and reported catching about 3.3 fish per trip.

3. Few (2 - 8 %) rainbow trout stocked in 1997 survived until April 1998, despite the fact that return rates were low (7 - 31%). About 17% of the brown trout stocked in May 1997 survived until April 1998, and their rate of return to the creel was 23%. These return rates were much less than in 1995 because of unusually high flows observed in late spring and early summer of 1997, when fishing pressure usually peaks.

4. Rainbow trout stocked early in 1997 grew faster (13 mm and 20 g/month) than later-stocked cohorts. Brown trout grew slower (8 mm and 10 g/month) in summer and fall than in winter (17 mm and 61 g/month). Three brown trout tagged and stocked in 1995 averaged 484 mm (19 inches) and 1.3 kg (2.9 pounds) after 24 months in the river. The robustness of stocked trout followed seasonal trends corresponding to the quality of water released from the dam.

5. Trout stocked in the lower reach of the tailwater were rarely observed in the creel, suggesting that better access is needed in that reach, or stocking at the Stonewall bridge should be curtailed.

6. Few trout (less than 9,000) overwintered between 1996 and 1997. Significantly more trout (about 28,000) overwintered between 1997 and 1998, due to a large stocking of rainbow trout in December 1998. The standing crop of both trout species combined each spring was uniformly low both years (41 and 74 kg/hectare, respectively) compared to standing crops observed in east Tennessee tailwaters such as the Clinch River and South Fork of the Holston River.

7. Stocked brown trout survived much better than rainbow trout, although brown trout in the Caney Fork River survived at a lower rate than in the Clinch and South Fork of the Holston rivers. Although six times as many catchable rainbow trout as brown trout were stocked in 1997, brown trout represented 34% of the biomass of trout overwintering through March 1998.

8. Only one fingerling brown trout of the 20,000 stocked in 1997 was observed in the April 1998 samples; the total number of those fish overwintering was estimated to be only 218 fish. Previous studies on the Caney Fork River also observed poor survival of small fingerlings stocked early in the year. Stocking fingerling brown trout in late fall or early winter might succeed because growth would be rapid and fish entering the fishery the following spring would be more robust; however, stocking fingerlings at any other time of year should be discontinued.

9. As in previous years, dissolved oxygen concentrations in the discharge of Center Hill Dam fell as low as 0.9 mg/L in the summer and fall of 1997. Those hypoxic conditions were acutely lethal to trout stocked near the dam in early October 1997. The magnitude and duration of hypoxic releases were exacerbated by higher-than-normal precipitation earlier in the year.

10. The pool:run:riffle ratio at baseflow was 1.9 : 1.0 : 1.2, although pools accounted for almost 90% of the total surface area (135 hectares) in the 26-km reach of the river surveyed. Instream cover was sparse. Bank erosion was severe throughout most of the tailwater.

11. The ability of the Caney Fork river to sustain high densities of trout is clearly limited by seasonal deficits in dissolved oxygen and low abundance of quality habitat. Until improvements to water quality and habitat are made, management efforts should focus on adjusting stocking times and sizes to maximize the potential of the fishery. Compared to other tailwater trout fisheries in Tennessee and elsewhere, there are not as many options available for managing the Caney Fork fishery using harvest or gear restrictions. Although clear goals for that fishery have not been established, the brown trout fishery could be enhanced with higher stocking rates and harvest restrictions to take advantage of their ability to survive better under current environmental conditions.