KIRSTEN R. POLING AND LEE A. FUIMAN, University of Texas at Austin Marine Science Institute, 750 Channelview Drive, Port Aransas, Texas 78373, USA

Red drum, spotted seatrout, and Atlantic croaker larvae all utilize an inshore nursery habitat, but the extent of this usage depends on the species. Responses of these sciaenids to a model predator were examined throughout the larval period to determine whether the sensory systems important for evading predators are related to species-specific habitat usage. Red drum, croaker, and seatrout all had high responsiveness under control conditions. When larvae were approached in darkness, red drum and seatrout had higher responsiveness than did croaker. When larvae were able to see, but the lateral line was not functional, red drum and seatrout had generally decreasing responsiveness, while croaker had generally increasing responsiveness. Similar trends were seen in the distance at which larvae responded to the stimulus. Seatrout and red drum responded at a larger distance from the stimulus in the dark than did croaker. Croaker responded at a larger distance than the other species when the lateral line was not functional. Differences in behavioral development appear to be related to patterns of habitat usage of these three species. These findings suggest that the microhabitat characteristics for optimal predator evasion, and thus survival, may be different for these three species.