Reallocation scenarios for artisanal fishing effort in the presence of an aquaculture site: A GIS-integrated Bayesian belief network for spatial conflict resolution in the Bay of Biscay

The competition for marine space is a recognized challenge, and the implementation of new activities, such as those emerging from Blue Growth initiatives, may amplify this competition. Thus, in order to minimize conflicts and maximize the sustainable use of marine areas, new spatial management plans must be developed. Specifically, the MSP framework requires decision makers to analyse spatially explicit environmental and socio-economic data to determine where user conflicts are or might emerge and consider several potential management scenarios. GIS-integrated Bayesian belief networks (BBN) can be used for this purpose, by integrating relevant information derived from both empirical data and expert judgment. Here, we use a BBN to analyse the potential reallocation of artisanal fishing effort to alternative sites due to the introduction of a new, non-take area: an offshore aquaculture site along the Basque coast. The constructed model combines discrete, operational fisheries data, continuous environmental data (e.g. benthic habitat maps), and expert judgment to produce continuous coverage suitability maps for fishing activity. The BBN was run with various marine use scenarios, and the obtained results can be used to identify alternative fishing locations based on environmental suitability, past revenue, and past fishing presence. The present research demonstrates how BBNs can support spatially explicit scenario building and useruser conflict analysis in the context of marine spatial planning.