Data from: Ocean circulation model predicts high genetic structure in a long-lived pelagic developer

Understanding the movement of genes and individuals across marine landscapes is a long-standing challenge in marine ecology, and can inform our understanding of local adaptation, the persistence and movement of populations, and the spatial scale of effective management. Patterns of gene flow in the ocean are often inferred based on population genetic analyses coupled with knowledge of species’ dispersive life histories. However, genetic structure represents time-integrated processes, and may not capture present-day connectivity between populations. Here we use a high-resolution oceanographic circulation model to predict larval dispersal along the complex coastline of western Canada, separating two previously-established zoogeographic provinces. We simulate dispersal in a benthic sea star with a 6-10 week pelagic larval phase, and test predictions of this model against observed genetic structure within this region. We also test predictions with new genetic sampling in a site within the phylogenetic break. We find that the genetic and circulation models both predict the high degree of genetic structure observed in this species, despite its long pelagic duration. High genetic structure on this complex coastline can therefore be explained through advective circulation patterns, validating the utility of this model for predictions at a broad scale.