Wetland protection gaps in China: Insights from small and/or isolated wetlands (SIWs)

The establishment of protected areas remains a cornerstone strategy for conserving wetland ecosystems. However, many SIWs in China remain excluded from national conservation frameworks, despite their ecological importance. To address this gap, we developed a rapid assessment model integrating four key indicators — wetland area, waterfowl species richness, waterfowl abundance, and dominant wetland plant richness—to identify and evaluate unprotected SIWs at a national scale. The assessment was supplemented by expert-sourced online questionnaires to enhance data coverage, particularly for regions lacking systematic monitoring. A total of 1,473 unprotected SIWs were identified, encompassing approximately 3.39 million hectares. These wetlands represent critical conservation gaps in the current protected area network. Incorporating them into the national wetland protection system would raise China’s protection level from 50.22% to 58.01%, surpassing the governmental target of 55% by 2035. Many of these SIWs are located along major migratory bird routes and in biodiversity-rich zones, underscoring their strategic ecological value. This study provides the first systematic evaluation of SIWs at the national level in China and proposes a scalable, data-driven framework for prioritizing wetland protection. The results offer actionable guidance for enhancing wetland conservation and contribute to the broader goals of the Global Biodiversity Framework and the Ramsar Convention.