Frank 9313872 Vertical migration has been described as one of the dominant behavioral patterns on earth. The influence of this phenomenon on the structure of marine ecosystems is well documented, and defining the environmental variables which control this behavior is critical to developing predictive models of animal distributions in the ocean. It is generally accepted that light is the variable which exerts the greatest influence over migratory behavior. This study will conduct experiments on deep-sea species, whose ambient light field contains few variables and is therefore more easily reproduced. Due to the recent discovery of near-UV light sensitivy in several species of deep-sea, vertically migrating shrimp, in situ measurements of both visible and near -UV light will be made and utilized to provide a calibrated light field for behavioral and electrophysiological experiments designed to define the critical photic determinants of vertical migration. ***
