Translocation of larval coral reef fishes via sub-mesoscale spin-off Eddies from the Florida current

Abstract

Meanders and spin-off eddies of the Florida Current (FC), remotely sensed via a shore-based high frequency Doppler radar system, revealed mechanisms of cross-frontal exchanges essential for larval transport and recruitment. Larval fish assemblages were analyzed by computing Margalef diversity coefficients and employing Bray-Curtis dissimilarity coefficient and UPGMA-linkage based multivariate cluster analysis. Horizontal trajectories were computed for parcels of surface water to estimate origination and destination of reef fish larvae at each station. Our results suggest that spin-off eddies in the south Florida Keys allow reef fish larvae access to inshore settlement sites via shoreward translocation across the strong FC frontal boundary. Additionally, they may retain postflexion coastal species and may increase along-shore dispersal of locally-spawned early larvae by moving them along the edge of the meandering FC front.