Dispersal of a near-shore marine fish connects marine reserves and adjacent fished areas along an open coast

Marine species with pelagic larvae typically exhibit little population structure, suggesting long distance dispersal and high gene flow. Directly quantifying dispersal of marine fishes is challenging but important, particularly for design of marine protected areas (MPAs). Here, we studied kelp rockfish (Sebastes atrovirens) sampled along ~25 km of coastline in a boundary current-driven ecosystem and used genetic parentage analysis to identify dispersal events and characterize them, since the distance between sedentary parents and their settled offspring is the lifetime dispersal distance. Large sample sizes and intensive sampling are critical for increasing the likelihood of detecting parent-offspring matches in such systems and we sampled more than 6,000 kelp rockfish and analyzed them with a powerful set of 96 microhaplotype markers. We identified eight parent-offspring pairs with high confidence, and they included two juvenile fish that were born inside MPAs and dispersed to areas ou...