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<br />Transac:ions olchi! Ami!rican Fisht!rii!s Society I] 8:400-408, 1989
<br />Cl Copyright by the ^,merican Fisheries Society 1989
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<br />Dietary Toxicity of Selenium-Contaminated
<br />Red Shiners to Striped Bass
<br />
<br />DAVID J. COUGHLAN AND JOHN S. VELTE
<br />
<br />Duke Power Company, Production Environmental Services
<br />13339 Hagers Ferry Road, Huntersville. North Carolina 28078, USA
<br />
<br />Abstract.-Red shiners Notropis lutrensis (weight, about 1 g each) from the selenium-affected
<br />areas of Belews Lake, North Carolina, a cooling reservoir for an electric power plant, were fed to
<br />striped bass Morone saxati/is (about 250 g each) in a laboratory experiment. Consumption of red
<br />shiners (whole-body selenium concentration, 9.6 p.g Se/g wet weight) by striped bass was foIlowed
<br />by modified behavior, little increase in weight, a reduced condition factor (I Os. weight/length3), an
<br />elevated selenium concentration in muscle (3.8 p.g Se/g wet weight), histological damage to the
<br />liver and trunk kidney, and the death of all fish within 78 d. Striped bass fed a comparable,
<br />uncontaminated diet of golden shiners Notemigonus crysoleucas (about I g each) gained weight,
<br />increased their condition factor, had muscle selenium concentrations averaging 1.1 p.g Se/g wet
<br />weight, and exhibited no histological abnormalities or reduced survival during the 80-d experiment.
<br />Toxicity and death induced by selenium-contaminated prey fish may contribute to the absence of
<br />piscivorous game fish in selenium-affected regions of Belews Lake.
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<br />Selenium is a trace element that has become of
<br />great environmental concern. Although it is re-
<br />quired by most organisms as a micronutrient, it
<br />can be toxic when ingested in excess (NRC 1983).
<br />Gross contamination can occur in aquatic envi-
<br />ronments that receive drainage from seleniferous
<br />soils, such as Kesterson Reservoir, California (Sai-
<br />ki and Lowe 1987), or power plant cooling res-
<br />ervoirs that receive ash-basin sluice water, such
<br />as Martin Lake, Texas (Garrett and Inman 1987),
<br />and Belews Lake, North Carolina (Olmsted et al.
<br />1986).
<br />Be1ews Lake is al ,564-hectare reservoir that
<br />was impounded by Duke Power Company in 1970
<br />to provide cooling water for a coal-fired electric
<br />power plant. The lake is located in north-central
<br />North Carolina, drains into the Dan River (Figure
<br />I), and has an average water-retention time of
<br />1,500 d. From 1972 to 1975, the lake supported
<br />a fish community of centrarchids, ictalurids, cyp-
<br />rinids, and clupeids (Harrell et al. 1978). In 1975,
<br />the overflow from the ash basin of the power plant
<br />began discharging into the downlake areas of Be-
<br />lews Lake (Olmsted et al. 1986). Cove rotenone
<br />sampling near the ash-basin discharge in 1976 re-
<br />vealed declining fish populations, especially game
<br />fish. Fish standing stock, as determined by cove
<br />rotenone sampling (1978-1986) near the ash-ba-
<br />sin discharge, averaged 28 kg/hectare (3-12
<br />species); in contrast, standing stock averaged 225
<br />kg/hectare (19-23 species) at a hydrologically re-
<br />mote uplake site (Duke Power Company, unpub-
<br />lished data). Cyprinids and poeciliids together have
<br />accounted for 96 and 6% of the total number of
<br />
<br />fish at the ash-basin site and the uplake site, re-
<br />spectively, during these same years. The lack of
<br />predators in the downlake fish comr:" unity has been
<br />attributed to the limited flushing and the uptake
<br />of ash-basin-derived trace elements, particularly
<br />selenium, through the food chain (Cumbie and
<br />Van Horn 1979; Lemly 1985). Fish accumulate
<br />selenium primarily by dietary exposure rather than
<br />waterborne exposure (Sandholm et al. 1973). Ear-
<br />ly field studies conducted at Belews Lake impli-
<br />cated predation on contaminated benthos as one
<br />source of selenium toxicity to predatory game fish
<br />(Harrell et aI. 1978). Finley (1985) confirmed the
<br />dietary toxicity of selenium-contaminated mayfly
<br />nymphs Hexagenia limbata to bluegills Lepomis
<br />macrochirus in a laboratory experiment. How-
<br />ever, the potential toxicity of abundant prey fish
<br />from the downlake regions of Belews Lake to
<br />predatory game fish had gone untested.
<br />The objective of this study was to investigate
<br />the dietary toxicity of a prey fish species from
<br />Belews Lake to a piscivorous fish species. Striped
<br />bass Morone saxatilis fed live, selenium-contam-
<br />inated red shiners Notropis /utrensis from Belews
<br />Lake were examined for changes in gross mor-
<br />phology and behavior, histopathology, and sele-
<br />nium accumulation in a laboratory experiment.
<br />
<br />Methods
<br />
<br />Striped bass were electro fished from Lake Nor-
<br />man, North Carolina, on 8 January 1985 and ac-
<br />climated to laboratory well water at 20"C for 2
<br />weeks. During acclimation, the striped bass were
<br />fed fathead minnows Pimepha/es prome/as and
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