El Niño enhances coral larval dispersal potential of Dongsha Island—a biodiversity hotspot in the South China Sea

Introduction Larval dispersal and connectivity play a critical role in sustaining the diversity and resilience of coral ecosystems. Dongsha Island, which exhibits extraordinarily high coral biodiversity and lies along a key pathway from the Coral Triangle to the South China Sea (SCS), has unclear coral larval dispersal and demographic linkages with other coral reefs. Methods Using biophysical simulations, this study depicts the spatiotemporal pattern of coral larval dispersal potential of Dongsha Island. Results Following a strong El Niño event, coral larval dispersal potential of Dongsha Island is expected to enhance toward the southwest, driven by intensified westward ocean currents. Discussion This finding highlights the influence of climate change on coral larval dispersal in the SCS from an air-sea dynamic perspective and underscores the pivotal role of Dongsha Island in the West Pacific marine ecosystem. Dongsha Island may act as a key modulatory node for connectivity of coral communities in the Coral Triangle and the SCS, particularly under changing climate conditions, as the frequency of super El Niño events is projected to increase.