High self-recruitment levels in a Mediterranean littoral fish population revealed by microsatellite markers

Self-recruitment rates are essential parameters in the estimation of connectivity among populations, having important consequences in marine conservation biology. Using ten highly polymorphic microsatellite loci, we estimate, over 3 years, the self-recruitment in a population of Tripterygion delaisi in the NW Mediterranean. Six previously described source populations were used for the assignment (Costa Brava, Columbretes, Formentera, Cabo de Palos, Cabo de Gata and Tarifa). Even though this species has a 16-21 day larval duration, a mean of 66.4 +/- 1.4% of the recruits settled in their natal population. When refining in a more local scale the origin of individuals self-recruited to Costa Brava, using as source the three sampling localities that conform this population (Cap de Creus, Tossa and Blanes), the highest percentage (40.6 +/- 8.9%) was self-assigned to the adult source locality (Blanes) where recruits were sampled each year. Our results suggest that a high proportion of the larvae of T. delaisi remained close to, or never leave, their natal spawning area. This observation can be extrapolated to other species with similar early life-history traits and low adult mobility and can have important implications for the conservation and management of Mediterranean littoral fishes.