Aquatic organisms often find their prey by recognizing and following chemical cues dissolved in the water. This work will determine the identity and physical transport of odorant molecules governing olfactory-mediated predation by the blue crab. Biochemical techniques will be used to characterize the chemical attractant molecules, electrochemical instrumentation will be used to investigate the nature of the odor "plume" structure, and a flume apparatus will be used to link hydrodynamic processes and boundary layer considerations to odor plume structure and predatory success. The results will be important to sensory neurobiology, to field ecology on this important estuarine predator, to biological oceanographic considerations of hydrodynamics and ecology, and are likely to have an impact on developing aquaculture of this major commercial species.