Four species of piscivorous fishes (coneyEpinephelus fulvus; schoolmasterLutjanus apodus; mahogany snapperL. mahogoni; and largemouth bassMicropterus salmoides) displayed distinct behavioral abnormalities after consumption of a ciguatoxic great barracudaSphyraena barracuda. Samples of the great barracuda were fed to experimental fishes as ether-soluble extracts or as ground flesh. Largemouth bass were also fed freeze-dried cells of the dinoflagellateGambierdiscus toxicusin a separate experiment and displayed a similar response, Signs of intoxication included skin color variations, inactivity, loss of equilibrium, erratic swimming, jerky feeding movements, and loss of orientation – and death, in the case of largemouth bass fed 1.0 g or more of great barracuda flesh or 7.1 mg·g–1or more of great barracuda extract. These abnormalities usually were observed within 24 h after the feeding of toxic materials, and were apparent in some cases for as long as 76 d.