Extreme climate events such as heatwaves pose conservation and socio-economic challenges. The Mediterranean Sea, considered as a hotspot of biodiversity and climate change, is a striking example of these challenges. Since two decades, mass mortality events induced by marine heatwaves dramatically impact coastal habitats, driving populations of 50 taxa close to extirpation. Following the 2022 marine heatwave, a historical mortality event was observed in the Parc National des Calanques (PNC, France). In particular, populations of the habitat-forming red gorgonian, Paramuricea clavata, showed high mortality, with dramatic consequences for the functioning and aesthetic of the ecosystem.

Standing on an international consortium including the PNC, the BUFFER project aims to boost two Nature-Based Solutions (NBS) to protect P. clavata, using an innovative approach focused on genetic diversity. Genetic diversity is poorly considered in conservation in spite of its role to support population resilience and evolutionary potential (Aichi Biodiversity strategic plan). Combining field work until the mesophotic zone with cutting-edge population genomics, we will 1) develop climate-resilient transplantation protocols based on a sourcing tool to identify thermoresistant colonies (NBS1: efficient restoration); 2) provide scientifically-driven recommendations for management prioritization (NBS2: effective conservation). In parallel, we will develop a proactive dissemination and communication strategy towards biodiversity managers (reports and science-policy meeting) and general audience (video and conferences).

Improving the conservation status of P. clavata, we will strengthen the climate resilience of associated communities in the PNC, with positive impact for local ecosystems and stakeholders. The BUFFER project will sustain the general public awareness while paving the way for the development of an integrative biodiversity management in Mediterranean marine protected areas.