OPS 5-8
Spatio-temporal variation in the diversity of target species in Baja California Sur, Mexico
Both theory and empirical work have demonstrated that diverse ecological assemblages can contribute to resilience, allowing social-ecological systems (SESs) to persist in spite of environmental variability and change. In the context of fisheries SESs, Worm and colleagues (2009, Science) found that fisheries characterized by more diverse catches were more resilient to over exploitation. A diversity of target species also can expand fishers’ opportunities and contribute to adaptive capacity [as shown by Hilborn and colleagues (2003, PNAS) in the case of the Bristol Bay salmon fishery]. The response diversity inherent in a more speciose set of target species also may contribute to faster recovery following environmental shocks. Here we report on analyses of historical catch data from Mexico’s National Commission of Aquaculture and Fisheries (CONAPESCA) for the state of Baja California Sur. We investigate the spatial and temporal dynamics of reported landings from 10 fishing offices from 2001 to 2013 to address the question: How does the richness and composition of reported landings vary through space and time?
Results/Conclusions
We find that taxon richness of reported landings is highly variable among the fishing offices, ranging from 48 to 133 taxa over the 13 years of available data. The composition and value of these fished assemblages also varies geographically. Fishing offices on the Pacific coast of Baja California Sur experience a larger variance in taxon richness, and have significantly lower diversity of landings than those on the Gulf of California coast. Taxon richness increased significantly over the 13-year time frame for two of the 10 offices (both on the Pacific coast); these changes are responsible for a statewide increase in taxon richness from 2001 to 2013. Placing these trends in the context of regional oceanographic and demographic variability will enable us to develop a more mechanistic understanding of if and how diversity of target species is contributing to resilience of BCS’ fisheries and fishers.