Larval Transport Pathways Reveal Critical Habitat and Benefits of a Marine Protected Area to Fisheries

ABSTRACT Quantifying where marine organisms are born and subsequently disperse to is essential for fisheries management. Here, we conducted Lagrangian particle tracking of viviparous rockfish ( Sebastes spp.) collected in the Southern California Bight over the course of 16 years. Particle tracking was performed forward‐ and backward‐in‐time to investigate birth locations and dispersal patterns of rockfish larvae, respectively. Otolith core width at extrusion was used as a proxy for larval condition at birth. We found that high‐quality larvae may have been born in offshore locations and subsequently advected throughout the region, including into large marine protected areas (e.g., Cowcod Conservation Areas). Additionally, 24% of larvae that were born in the Cowcod Conservation Areas remained within the reserve boundaries after 30 days, while the majority were advected to surrounding areas. Our analyses illustrate the utility of coupling particle tracking methods with in situ collections to better identify areas that are hotspots for the production and growth of high‐quality larvae.