A social-ecological system framework to assess biological invasions: Corbicula fluminea in Galicia (NW Iberian Peninsula).
In this study we hypothesize that Ostrom's social-ecological system (SES) framework can be useful to address the introduction pathways and dispersal vectors of non-native species. We have applied this framework to the introduction of the Asian clam Corbicula fluminea in freshwaters in Galicia (Spain). We reviewed scientific and grey literature and performed a series of interviews with key stakeholders. This information, coupled with an extensive survey campaign, provided an updated C. fluminea distribution map. Using a Principal Component Analysis and pair-wise correlations we analyzed a set of 18 social, ecological, economic and governance variables and related them to the total number of water bodies invaded by C. fluminea in Galicia. Our field data on C. fluminea distribution indicated a mean upstream spread of 3.6 km yr-1. We suggest that the total number of water bodies invaded by C. fluminea in Galician freshwaters is mainly linked to the following variables of the social (higher education level and mass media news), ecological (endangered freshwater species, scientific publications, dams, wastewater treatment plants, livestock, and agricultural lands), economic (gross domestic product, gross imports, and industrial productivity index) and governance (surveillance, legislative instruments and non-governmental organizations) dimensions. The SES framework has been useful in identifying introduction pathways and dispersal vectors of non-native species. We encourage decision-makers to get involved in real implementation of legislative instruments and management plans that will be benefitted by collaborating efforts between stakeholders.