Comparison of low oxygen avoidance in a bimodal breather,Erpetoichthys calabaricus and an obligate water breather,Percina caprodes

Synopsis Behavioral responses of the African reedfish, Erpetoichthys calabaricus, (Polypteridae), a bimodal breather, and the logperch, Percina caprodes, (Percidae), an obligate water breather, to low concentrations of dissolved oxygen were examined in a two-choice experimental design. In contrast to logperch, which consistently avoided dissolved oxygen concentrations of about 2.0 mg 1⁻¹, reedfish did not exhibit strong avoidance to dissolve oxygen concentrations of 0.5 mg 1⁻¹ and less.