Building evolutionary resilience: a framework for managing safe haven populations

Safe havens are widely used to mitigate the impacts of invasive predators on threatened species, yet their isolation often disrupts evolutionary processes and can leave them vulnerable to environmental change and stochastic events. We present a framework for integrating evolutionary principles into safe haven management, termed 500-in-5, which establishes a metapopulation of >500 breeding individuals distributed across five geographically separated safe havens spanning environmental gradients. Using genetic and demographic simulations for two threatened Australian mammals, we demonstrate how this approach can enhance adaptive potential and persistence. Spatially explicit population models predict that many existing safe havens are at risk of collapse within decades. However, genetic simulations show that selection on standing genetic variation can drive fitness gains within tens of generations, improving population resilience to novel conditions. Integrating these processes reveals that safe haven networks can promote adaptation and resilience, substantially improving long-term persistence and providing robust sources for reintroductions.