Yi Han

Evaluating the effectiveness of freshwater protected areas (FPAs) is crucial for improving their performance, yet evidence remains limited. Using remote sensing and field surveys from 2001 to 2017, we examined FPA coverage, their efficacy in preventing species decline and habitat deterioration, and strategies to enhance FPA effectiveness for the critically endangered Yangtze finless porpoise ( Neophocaena asiaeorientalis asiaeorientalis ). FPAs failed to cover nearly half of high‐abundance regions and two thirds of medium‐abundance areas. Despite initially better conditions, FPAs experienced similar or greater species declines and habitat deterioration. Porpoise distribution closely correlated to habitat conditions, with abundance declining most in severely degraded floodplains while remaining stable or increasing in less disturbed areas. To improve FPA performance, we recommend expanding protection to medium‐ and high‐abundance areas to better cover key porpoise habitats and enhancing existing FPAs through stricter law enforcement, proactive management, and targeted restoration. These strategies are reinforced by China's new legal and policy framework for Yangtze River protection, providing a foundation for long‐term conservation.

Sand mining, which has tripled in the last two decades, is an emerging concern for global biodiversity. However, the paucity of sand mining data worldwide prevents understanding the extent of sand mining impacts and how it affects wildlife populations and ecosystems, which is critical for timely mitigation and conservation actions. Integrating remote sensing and field surveys over 14 years, we investigated mining impacts on the critically endangered Yangtze finless porpoise ( Neophocaena asiaeorientalis asiaeorientalis ) in Dongting Lake, China. We found that sand mining presented a consistent, widespread disturbance in Dongting Lake. Porpoises strongly avoided mining sites, especially those of higher mining intensity. The extensive sand mining significantly contracted the porpoise's range and restricted their habitat use in the lake. Water traffic for sand transportation further blocked the species's river–lake movements, affecting the population connectivity. In addition, mining-induced loss of near-shore habitats, a critical foraging and nursery ground for the porpoise, occurred in nearly 70% of the water channels of our study region. Our findings provide the first empirical evidence of the impacts of unregulated sand extractions on species distribution. Our spatio-temporally explicit approach and findings support regulation and conservation, yielding broader implications for sustainable sand mining worldwide.