Valorization of marine biodiversity to engage local communities in the design of tailored conservation measures

Marine biodiversity represents both a natural heritage and a powerful catalyst for public engagement in conservation. However, bridging the gap between ecological knowledge and local community participation remains one of the main challenges in promoting sustainable management of marine ecosystems. This PhD research aimed to explore and integrate diverse approaches to enhance the role of marine biodiversity in supporting shared management and the design of context-specific conservation strategies, within a Mediterranean context increasingly affected by stressors and change. Adopting a multi-level framework, the study investigated three complementary research lines: Ocean Literacy (OL), Local Ecological Knowledge (LEK), and Marine Biodiversity Monitoring (MBM). Each research line provided specific insights into how marine biodiversity can serve as a starting point to engage communities, inform decision-making, and strengthen participatory governance mechanisms. The OL line demonstrated how education, both formal and informal, represents a key tool to build more conscious relationships between people and the sea. Targeted strategies were developed to increase public awareness and acceptance of conservation measures, including Marine Protected Areas (MPAs), with a particular focus on integrating marine education into school curricula and engaging adults in participatory marine spatial planning. As a direct result of this work, some local schools involved in the project joined the European Blue School Network. The LEK line offered a qualitative and cost-effective approach to reconstruct long-term ecological baselines, by incorporating the knowledge of diverse sea users, such as artisanal fishers and divers. The findings highlighted major shifts in species composition - such as the decline of traditionally commercial taxa and the increase of thermophilic and opportunistic species - emphasizing the value of LEK as an effective complement to conventional scientific monitoring and a useful tool to detect climate-driven changes. This research line also triggered marine conservation initiatives in two different areas of the Mediterranean, both strongly rooted in coastal community engagement. The MBM line produced the first systematic seasonal assessment of Heterobranchia along the Conero Promontory Coast (CPC), contributing a reference dataset for future biodiversity monitoring. The multi-source protocol applied in this study proved effective in identifying spatial, trophic, and seasonal patterns, while also highlighting important methodological considerations for optimizing Citizen Science (CS) contributions. The findings confirmed the ecological sensitivity and bioindicator potential of heterobranchs, particularly in the context of ongoing environmental change. Across all research lines, this work identified knowledge gaps, methodological challenges, and tangible opportunities to improve collaborative monitoring practices. It highlighted the importance of integrating scientific rigor with inclusive participatory approaches to foster a shared sense of responsibility in marine protection. Ultimately, this research contributes to the development of adaptive and locally tailored strategies, supporting more equitable, effective, and ecosystem-based marine management models.