The rich motor program exhibited by Daphnia, keystone species in many freshwater ecosystems, allows them to move away from predators and acquire food. Although studies of their movement have been ongoing for decades, little is known about the development and neurochemical underpinnings of this motor program. We have developed high-speed video imaging tools to study the swimming behavior in Daphnia magna. Analysis of individual animal data has enabled us to define discrete bouts of swimming and to describe a variety of swimming parameters. Dopaminergic drugs applied to animals perturb swimming behavior, thus suggesting a role for dopaminergic signaling in the control of swimming in Daphnia.  The present studies are focused on the development of the swimming program and the role of dopamine in controlling it.