Greek protected areas fail to fully capture shifting endemism hotspots under future climate and land-use change: The case of Peloponnese

In the Anthropocene, conservation planning must adapt to rapid environmental changes driving the global biodiversity crisis. The impacts of climate and land-use change are particularly severe in biodiversity hotspots like the Mediterranean Basin, where unique taxa and ecosystems are increasingly at risk. To address these challenges, we conducted a forward-looking conservation gap analysis in Peloponnese, Greece, a regional endemism centre and key component of the Mediterranean biodiversity hotspot, providing a case study to support the development of cost-effective conservation strategies. We applied a taxonomically and phylogenetically informed approach to identify endemism hotspots across different time-periods. Persistent hotspots were mapped under future climate and land-use scenarios, and their overlap with protected and roadless areas was assessed. Our analysis revealed that endemism hotspots will likely shift geographically and diminish in extent over the coming decades. While key mountainous regions are expected to retain their hotspot status, our results point to a widespread decline in endemism and overall biodiversity loss. Concerningly, the most critical persistent hotspots overlap with extinction risk hotspots. Moreover, up to 46 % of the persistent endemism hotspots are not covered by designated protected areas, and <8 % of those lie within roadless areas. Our results highlight the need for a coordinated multi-dimensional strategy that should include the expansion of the current network of protected areas, the establishment of plant micro-reserves, and the translocation and reinforcement of populations of endemics. The identified conservation gaps represent regions of enduring resilience to environmental change, making them critical targets for long-term conservation planning. • Climate and land-use change threaten the survival of Peloponnese's unique endemic flora. • Plant endemism hotspots in Peloponnese are projected to shift and decline. • Current conservation schemes are insufficient to accommodate future endemism shifts. • We propose forward-looking strategies that account for multiple future scenarios.