Dynamic marine spatial planning for conservation and fisheries benefits

The increasing global demand for marine resources raises concerns about sustainable resource management and biodiversity conservation. Spatial closures, such as marine protected areas, can be valuable tools for maintaining and restoring exploited populations. When these spatial closures adopt a dynamic nature being adapted to the changing environment, they can effectively account for factors such as shifting species distributions, which enhances their potential to achieve ecological and socio-economic objectives. Here, we adapted a decision-support tool (the software Marxan), typically used for selecting static and permanent areas, to produce management recommendations that integrate permanent and temporal closures to fisheries. Our aim was to compare the outputs of a static network of permanent no-take reserves with four other dynamic scenarios, including permanent and temporal closures that account for seasonal variations in the populations of species. All scenarios prioritized sites for the conservation of one of the most valuable European fishing stocks, the Norway lobster (Nephrops norvegicus). Additionally, we considered 12 other commercially exploited species captured by the Norway lobster fishery. The assessed outputs included retained biomass, area extent, closure type (permanent and seasonal) and opportunity costs within each scenario. We observed that all dynamic scenarios required fewer management areas permanently closed than the static scenario. This resulted in a lower opportunity cost for fisheries but also a higher capacity for biodiversity conservation. Therefore, complementing permanent with temporal closures could enhance biodiversity conservation and fisheries management. The novel dynamic planning method presented here could be applicable to other species, ecosystems and socio-economic contexts.