Fragmentation of Key Biodiversity Areas highlights attention to human disturbance patterns

Faced with a global biodiversity crisis, we need to concentrate our collective efforts on safeguarding Key Biodiversity Areas (KBAs), which serve as essential habitats for the world's threatened species. Clarifying the disturbance and protection requirements of KBAs is vital to the global persistence of biodiversity, which is not yet clear. Here, we evaluated the extent and severity of human disturbance in KBAs. Specifically, we analyzed the spatial patterns of disturbance and their potential effects on habitats. Roughly a quarter of terrestrial KBAs are challenged by crop production and urban construction activities, especially in Europe. The mean Human Footprint Index (HFI) for KBAs worldwide is 12.3, indicating a high level of human disturbance. On average, 62 % of each KBA is identified as Human Threatened Areas, signifying intense human impacts on these areas. 57 % of KBAs are subdivided by human disturbance, which can lead to substantial habitat fragmentation and loss of connectivity compared to other forms of disturbance. The halving of mean patch size and the tripling of the perimeter-area ratio for active habitats in KBAs provide evidence of the difficulties faced in conserving these areas. More importantly, increased coverage of Protected Areas fails to reduce HFI in KBAs, indicating some deficiencies in current protection systems. Therefore, we emphasize the importance of focusing on disturbance patterns for more impactful interventions, which potentially offer new pathways to mitigate adverse habitat impacts in post -2020 biodiversity conservation efforts.