The P.I. proposes to experimentally examine the influence of three apsects of the biotic neighborhood on zooplankton dispersal rates, the density, quality and type of neighbors experienced by an individual. Dispersal is likely to influence strongly the information and persistence of zooplankton patches. Dispersal will be analyzed with several measures including the net horizontal displacement of individual zooplankton over a specified time. Experiments will be conducted in large field enclosures (10,000) using the natural assemblage of plankton. Recent studies indicate that physical factors alone can not explain all of the of the observed small scale patchiness. However, very little is known of the influence of biotic factors (ie. interactions with other animals or food) on patchiness. The effect of three specific factors (food concentration, food quality and the density of cannibalistics) on zooplankton dispersal will be tested in the enclosures. All three factors have been shown t affect feeding, growth, reproduction, behavior, and fitness of some zooplankton, and thus are likely to influence the tendency if individuals to remain in or to leave a patch.
