Protected area impacts on the cover and growth of Brazilian mangrove forests

Protected areas (PAs) are fundamental to biodiversity conservation, yet their effectiveness largely depends on governance instruments such as management plans and participatory councils. In Brazil, mangroves are recognized as Permanent Preservation Areas, but they remain vulnerable to degradation due to weak enforcement, governance challenges, and policy setbacks. However, the extent to which protected areas and their governance structures contribute to mangrove conservation in Brazil remains unclear. We evaluated whether PAs positively influence mangrove conservation and whether governance tools enhance conservation outcomes. We analyzed 25 strictly protected PAs along the Brazilian coast, assessing mangrove coverage changes over time and investigating the role of management plans and councils. We found that fully protected PAs cover approximately 16.86 km² of mangroves, representing nearly 12 % of all Brazilian mangrove area. Our results indicate that while PAs provide stability by preventing fragmentation and loss, the presence of governance tools did not significantly improve mangrove conservation outcomes. These findings suggest that the mere existence of management instruments is insufficient for effective conservation, emphasizing the need for stronger enforcement, active stakeholder engagement, and targeted conservation measures. Addressing these governance gaps is crucial for securing the future of mangroves, which play a key role in climate change mitigation.