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 combinations of core areas and movement corridors. We modelled population size and genetic diversity across five dispersal thresholds, using spatially explicit genetic simulations, to assess how area and connectivity influence conservation outcomes. Results Our analysis reveals a strong, disproportionate relationship between habitat area and population size and genetic diversity. Even when controlling for overall extent, landscapes that protect 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 reinforce the fundamental importance of habitat area for biodiversity conservation, while suggesting that conservation initiatives based on connectivity may have limitations, particularly when corridors are relatively long and narrow, or exceed species’ dispersal abilities. While connectivity remains a valuable conservation tool in fragmented landscapes, our results indicate that expanding core habitat areas should be the primary focus, with corridor investments strategically targeted to specific cases.