Foraging behavior can influence dispersal of marine organisms

It has become increasingly apparent that widely varying behaviors of organisms (e.g., ontogenetic depth preference, selective tidal stream transport, position maintenance) can significantly influence dispersal and connectivity between nearby populations. However, more common day-to-day behaviors, such as foraging, are often assumed to have little effect on dispersal at larger scales (tens to thousands of kilometers). In this review, we (1) place foraging within the context of current knowledge on behaviors that influence dispersal and transport, (2) provide evidence for foraging behavior as a driving mechanism of distributions, and (3) present a meta-analysis of dispersal distances estimated for three dispersal hypotheses (passive, swimming directly against currents, and foraging behavior) from 59 studies that document oceanographic conditions and in situ organism distributions. Results of the analyses reveal that when foraging and aggregative behaviors are considered, dispersal distances for larvae and zooplankton could be hundreds of kilometers less than many current dispersal estimates. Reduced transport because of foraging implies that individual populations might be more isolated than currently accepted. These findings suggest that fine-scale organism behaviors should be considered in models aimed to improve conservation efforts. Since humans took to the seas for food, fisherfolk have understood the importance of finding the ‘honey hole’ to maximize catch per unit effort (Healey et al. 1990). Observations of multiple trophic levels, from phytoplankton to whales, aggregated in or near fronts and clines (areas often termed ‘honey holes’) have elicited several hypotheses concerning how physical processes and behavior influence organismal distributions and dispersal in the ocean (Wolanski and Hamner 1988; see reviews by Metaxas 2001; Genin 2004). However, the interactive effects of increased biological activity, organism behavior, and the physical environment of fronts and clines on the transport and dispersal of marine organisms have not been fully