Using simulation modelling to evaluate the relative efficacy of core area and corridor-based conservation designs for biodiversity conservation

Abstract CONTEXT: The efficient and effective design of protected areas is a fundamental challenge in landscape ecology, focusing on how spatial patterns of habitat influence conservation outcomes. This has sparked debate about the relative importance of habitat area versus connectivity in maintaining populations across fragmented landscapes. OBJECTIVES: We evaluate the relative importance of habitat area and connectivity by comparing counterfactual scenarios for landscape configuration on Borneo. We examine how habitat area and connectivity influence Sunda clouded leopard population size and genetic diversity across scenarios and dispersal abilities. METHODS: We compared 28 landscape scenarios on Borneo, incorporating all plausible combinations of core areas and movement corridors. Using spatially explicit genetic simulations, we modelled clouded leopard population size and genetic diversity metrics across five dispersal thresholds to compare how area and connectivity influence conservation outcomes. RESULTS: Our analysis reveals a strong, disproportionate relationship between landscape area and population size and genetic diversity. Even when accounting for landscape area, larger areas consistently provide superior conservation outcomes. Corridors showed minimal impact, becoming effective only at the highest dispersal thresholds. Habitat area emerged as the primary driver of conservation success, challenging assumptions about the importance of connectivity and highlighting the complex interactions between landscape configuration and species mobility. CONCLUSIONS: Our findings challenge paradigms in landscape ecology by demonstrating habitat area is more critical for biodiversity conservation than connectivity, especially where corridor lengths exceed species' dispersal abilities. Conservation strategies should therefore prioritise expanding core habitat areas, with corridor investments strategically targeted to highly mobile species.