9317741 Madin Chemical signals play an important role in the lives of many animals for orientation to food, selection of habitats and mates, and avoidance of predators. It has been shown that benthic animals detect and respond to chemical signals produced by other animals or food sources at distances of centimeters to many meters. This study will test the hypothesize that the micro- scale pattern of concentration distribution of odors in a current provides information that is used by animals for opientation toward the odor source. Laboratory and in situ experimental work will be carried out to describe and quantify the distribution of chemical signals in aquatic odor plumes, and the behavioral responses of crustaceans to those plumes. ***