Some effects of thermal history on the largemouth black bass, Micropterus salmoides (Lacepede), of two central Texas reservoirs receiving power plant effluents.

Mean annual growth of the first three age classes of largemouth black bass from Tradinghouse Reservoir was near the average growth reported in the literature for southern waters. Largemouth black bass collected from the discharge canals of Tradinghouse Reservoir (which has received power plant effluent for only 2 years) and Lake Creek Reservoir (which has received power plant effluent for 20 years) showed no difference in male or female gonadal development, condition factor, or thyroid activity; however, the largemouth black bass collected from the Tradinghouse Reservoir discharge canal showed signs of decreased physiological activity with respect to the Lake Creek sample. No significant detrimental effects of the power plant effluents were detected.