Abstract

The unprecedented strain on both the structure and function of marine eco- systems has led to calls for new management approaches to counter anthropogenic impacts in coastal oceans. Spatial management options, in general, and marine protected areas (MPAs) in particular, have been touted as methods for both maintaining biodiversity and managing fisheries. Continuing debates on the efficacy of MPAs have identified the need for spatial models that accurately capture marine population dynamics. Theoretical studies suggest that population connectivity (the exchange of individuals among geographically-separated sub-populations that comprise a metapopulation) plays a fundamental role in local and metapopulation dynamics, community structure, genetic diversity, and the resiliency of populations to human exploitation. Population connectivity, as largely driven by larval dispersal, therefore has recently emerged as a critical issue for marine systems. Both the implications of connectivity and the processes driving it pose new challenges for biological and physical oceanographers, population ecologists, and resource managers. As most coral reef fish have a dispersive larval stage preceding relatively sedentary juvenile and adult stages, the distance, direction of, and boundaries to larval dispersal will influence their demography and population genetic structure. We have recently shown through a spatially explicit modeling study that typical dispersal distances for population replenishment are on the order 10’s to a few 100 km. This scaling, coupled with a complex geographical and oceanographic setting results in a diverse pattern of connectivity among local populations of fish, with specific regions of relative isolation. Here we further explore this relationship as it is influenced by various life history characteristics. We find that these life history parameters have strong impact on the relative contribution of self-recruitment vs. subsidy to local populations. Further, the geographic patterns of connectivity are modified by these same biological characteristics demonstrating the strong bio-physical interactions that control population connectivity

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