A novel habitat-based approach to predict impacts of marine protected areas on fishers

While marine protected areas (MPAs) can simultaneously contribute to biodiversity conservation and fisheries management, the global network is biased towards particular ecosystem types, as it was largely established in an ad hoc fashion. The optimization of trade-offs between biodiversity benefits and socio-economic values increases implementation success and minimizes enforcement costs in the long run, but is often neglected in marine spatial planning (MSP). Although the acquisition of spatially explicit socioeconomic data is often perceived as a costly/secondary step in MSP, it is critical to account for lost opportunities by people whose activities will be restricted, especially fishers. Here we present an easily-reproducible habitat-based approach to estimate the spatial distribution of opportunity cost to fishers in data poor regions, assuming that the most accessible areas have higher values and their designation as no-take zones represents increased loss of fishing opportunities. Our method requires only habitat and bathymetric maps, a list of target species, the location of ports, and the relative importance for each port and/or vessel/gear type. The potential distribution of fishing resources is estimated from bathymetric ranges and benthic habitat distribution, while the relative importance of the different resources is estimated for each port, considering total catches (kg), revenues and/or stakeholder perception. Finally, the model can combine different cost layers to produce a comprehensive cost layer, and also allows for the evaluation of tradeoffs. The development of FishCake was based on data from a contentious conservation-planning arena (Abrolhos Bank, Brazil) in which attempts to expand MPA coverage failed due to fishers‟ resistance. The opportunity cost approach that we introduce herein allows for the incorporation of economic interests of different stakeholders and evaluation of tradeoffs among different stakeholder groups. The novel approach can be directly used to support conservation planning, in Abrolhos and elsewhere, and is expected to facilitate community consultation.