Tracing the Path to Extinction: Long-Term Impacts of Human and Environmental Factors on Tiger Survival in East Asia

Earth has experienced five major global mass biodiversity extinctions, and we are currently facing the sixth, which includes mammals, particularly carnivores, being among the most affected. Studying the remnant populations alone of the currently endangered species often provides limited information. It fails to reveal the scenarios of the early dynamics and key driving facts/factors that led to their population decline. Therefore, a comprehensive understanding of the dynamics of long-term faunal extinction is not just an academic pursuit, but a crucial necessity for developing or amending tangible conservation strategies and management. This study examines the extirpation trajectories of tigers, relying extensively on fossil databases in the Pleistocene and historical geographic changes during the Holocene. We estimated their extinction probability and relationship with anthropogenic and climatic changes using a moving time window modeling framework. It illustrates how the impacts of humans on nature have significantly influenced threatened animals. These human activities will continue to shape the future survival prospects of tigers in China. Our findings indicate that cropland expansion, human population growth, and forest reduction have profoundly driven tiger extinctions, particularly after 1850, when pervasive human activities led to the disappearance of wild South China tigers. We estimate that isolated tiger populations face extinction within roughly 67.8 years, emphasizing the need for habitat connectivity. This study highlights the critical role of reducing human activities in tiger habitats and offers a model for estimating extinction probabilities and thresholds, underscoring the urgency of conservation strategies tailored to anthropogenic and environmental threats.