No effects of fishery collapse on the genetic diversity of the Gulf of California Corvina, Cynoscion othonopterus (Perciformes: Sciaenidae)

Abstract

Collapsed marine fisheries could provide valuable data on the relationship between fishery exploitation and collapse on effective population size (Ne) and genetic diversity. The Gulf Corvina is a large sciaenid fish endemic to the upper Gulf of California, supporting a large-scale artisanal fishery. Concerns about overexploitation, historical population collapse, and sudden recovery highlighted the need to evaluate its current genetic diversity and demographic history to design better conservation and fisheries management strategies for the species. We genotyped eleven microsatellite loci on 187 Gulf Corvinas from fishery landings to evaluate genetic diversity, estimate Ne, and infer demographic history. While we found evidence of a demographic decline, we found no evidence of a genetic bottleneck caused by the historic demographic collapse of the species. The Gulf Corvina exhibited moderate levels of genetic diversity and an Ne of around 2500 individuals. These numbers could be preventing significant genetic diversity loss and inbreeding depression. We suggest the conservation status of the Gulf Corvina to remain as Vulnerable, as well as a regular demographic and genetic monitoring to be implemented to achieve a sustainable use.