THE GENETIC DIVERSITY AND POPULATION STRUCTURE OF BARRED SAND BASS, PARALABRAX NEBULIFER: A HISTORICALLY IMPORTANT FISHERIES SPECIES OFF SOUTHERN AND BAJA CALIFORNIA

We examined the contemporary genetic structure of the barred sand bass, Paralabrax nebulifer, a commonly fished species in southern California and Baja California, Mexico. Populations of barred sand bass in southern California have experienced severe declines in numbers over the last decade subsequently leading to severely depressed status of the recreational fishery. Such large population declines can lead to an overall decrease in genetic diversity. The present study examined the genetic diversity in this species (N = 365) using both the control region of the mitochondrial DNA and microsatellite markers for locations throughout California and Baja California. Both markers showed a high degree of genetic diversity and genetic mixing however there is some evidence of structuring between locations north and south of the San Quintin upwelling zone. Despite the weak structuring observed around the upwelling zone, barred sand bass throughout the northeastern Pacific likely comprise a single large population.