Locomotor hyperactivity induced in the bluegill sunfish, Lepomis macrochirus, by sublethal concentrations of DDT

A quantitative description of the effects of sublethal concentrations of DDT on the locomotor activity of the bluegill sunfish, Lepomis macrochirus, is presented. DDT-elicited hyperactive locomotor responses at all the concentrations examined (0.008, 0.01, 0.02, 0.04, 0.06, 0.08, 0.1, and 0.2 parts per billion (ppb)) and the degree of such responses were concentration dependent. Maximal effects at each concentration were observed within 8 days after addition of DDT to the environment. At their maxima, fish at 0.008 ppb were 1.3 times as active as control fish, whereas fish at 0.2 ppb were 3.0 times as active as controls. The effects of DDT on locomotor activity were not reversed even after the fish were transferred back into tap water for 2 weeks.