Environmental, social, and management aspects in a hotspot: Interaction networks between marine protected areas

Marine protected areas (MPAs) are territorial management instruments aimed at conserving ecosystem services, natural resources, protecting habitats, recovering degraded areas and safeguarding associated cultural values. Integrating MPAs into networks has been increasingly recognized as a more effective and successful approach to achieve their goals. In this study, we use social network analysis to assess the interaction networks of environmental, social and management aspects of the MPAs in the Atlantic Forest Central Corridor (Brazil), one of the world's most threatened biodiversity hotspots. Two hypotheses were tested: (i) geographically close MPAs are more likely to interact in certain aspects, and (ii) networks consist of densely connected subgroups of federal and state MPAs (managed by institutions with a broader geographic focus), which interact more among themselves and occupy central positions in the network, while municipal MPAs (managed by institutions with a local geographic focus) occupy a more peripheral or isolated positions. The results support the first hypothesis, indicating how central MPAs exert influence on geographically close areas, increasing their interaction capacities. The second hypothesis was partially supported, with municipal MPAs isolated in the environmental and management networks, but active in the social network. The environmental network showed the greatest number of interactions and was characterized by the formation of four groupings between MPAs, while the social network presented the greatest number of social actors, reaching the greatest strength of interaction between the MPA-actors and presented six groupings. The management network exhibited the formation of three groupings of MPAs and presented the greatest isolation between actors from different groups. Network analysis highlights the central role that some MPAs play in marine conservation and suggests that interactions between MPA managers form organically, but are influenced by homophily and historical components.