D. Hugh Barwick

Food of bluegills (Lepomis macorchirus), redear sunfish (L. microlophus), and largemouth bass (Micropterus salmoides) from Belews Lake was examined during their recovery from selenium (Se) contamination to evaluate the influence of diet on the continued bioaccumulation of Se in their skeletal muscle tissue. The redear sunfish and largemouth bass consumed food items that originated primarily from Belews Lake while bluegills consumed mostly terrestrial insects. Food items originating from the lake generally exhibited higher concentrations of Se and resulted in higher concentrations of Se in...

Discharge of selenium (Se)-contaminated water into Belews Lake, North Carolina, resulted in a significant decline in fish diversity and biomass. However, fish populations in this cooling reservoir slowly recovered during a 10-year period from this contamination once Se inputs into the lake ceased. During this period, Se concentrations in skeletal muscle of fish declined, number of taxa increased from 7 to 22, and estimated fish biomass increased from 5.67 to 79.66 kg/ha.

Electrical barriers were successful in blocking movements of gizzard shad (Dorosoma cepedianum), golden shiners (Notemigonus crysoleucas), rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta), and largemouth bass (Micropertus salmoides) stocked in a 24-m long canal during simulated modes of pumped hydropower operation. Blockage rates were highest during nongeneration (95%-97%) and generation (94%-97%), and lowest during pumping (83%-84%). These results indicate an electrical barrier may be useful in blocking fish from migrating into areas around hydropower projects where they...

Fish biomass and angler harvest data were collected from Keowee Reservoir during a period when thermal characteristics of this reservoir were significantly altered by operation of a large steam-electric power plant. Plant operation increased the heat load of the reservoir and depressed the depth of the thermocline. During the 22-year sampling period, fish biomass (primarily for nonsportfish taxa) declined, fishing effort increased, and angler harvest rates remained unchanged.

Relative abundance of several species of fish in the headwaters of Keowee Reservoir and in Jocassee Reservoir were estimated during the initial 9 years of operation by the Jocassee Pumped Storage Station. Several species of fish in each reservoir declined in abundance during this period, while others increased. We think the declines were related more to the chemical stabilization of these reservoirs than to pumped storage operations. The increases were related to stocking programs and natural population expansions.

The relative success of the Walhalla strain of brown trout (Salmo trutta) and the Wytheville and Winthrop strains of rainbow trout (S. gairdneri) was evaluated for 2 years in a put-grow-and-take stocking program in Jocassee Reservoir. Gill-net catches of brown trout increased during the 2-year study, while catches of rainbow trout of both strains declined rapidly after stocking and no rainbow trout were netted during the second year of the study. A total of 11.4% of the stocked brown trout and 1.6% of the rainbow trout were harvested by fishermen during the study. Poor survival of rainbow...

Food of silver redhorse (Moxostoma anisurum), redbreast sunfish (Lepomis auritus), green sunfish (L. cyanellus), and bluegills (L. macrochirus) was examined to determine whether or not these fish in the Hartwell Reservoir tailwater (Savannah River, Georgia-South Carolina) ate organisms entrained from the reservoir or displaced from the tail water during water releases associated with the production of hydropower. These fish fed primarily on aquatic insects, crayfish, and terrestrial organisms originating from the tail water. Major periods of feeding occurred during nongeneration.

Releases of large volumes of water from low-level release ports during generation of peaking hydropower at Hartwell Dam, Georgia-South Carolina, resulted in large daily flow fluctuations and altered water quality in a section of the Savannah River. Flows ranged from a minimum of 3 m3/sec during nongeneration to 665 m3/sec during generation. Thermal stratification in Hartwell Reservoir generally resulted in low water temperatures (≤20 C) throughout the 14-km study area and low dissolved oxygen concentrations <3 mg/I) in the 2-km section of the river immediately below the dam....

Food of larval (5.0-10.9 mm, TL) black crappies (Pomoxis nigromaculatus) from Keowee Reservoir, SC, was determined in 1973, before commercial power generation began from a 2,580-MW nuclear power plant, and in 1976 after 3 years of commercial power generation. Although water temperatures were higher in 1976 than in 1973, food of the larvae appeared to be unchanged by operation of the plant. The principal organisms eaten were Diaphanosoma sp._and copepod nauplii.

An investigation of the effect of two feeding rates on pond production of advanced fingerling striped bass was studied at the Auburn University Fisheries Research Unit from June 27 to November 24,1972. The mean survival for fingerlings fed a high feeding rate was 71.87% as opposed to 70.13% for fingerlings fed a low feeding rate. Mean production for fingerlings fed a high and low feeding rate was 266.44 kg/ha and 293.68 kg/ha. respectively. Food conversion for fingerlings fed a high feeding rate was 3.74 as compared to 2.51 for fingerlings fed a low feeding rate.