Reconstruction of Population-Level Migration Trajectories of Black-Faced Spoonbill () Based on Citizen Science Data.

Migration is a critical ecological process for birds. Understanding avian migratory routes is essential for identifying important stopover sites and key foraging areas to ensure high-quality stopovers for birds. The Black-faced Spoonbill (), a national Grade I protected wild animal in China, is classified as endangered on the IUCN Red List of Threatened Species. Studying the migratory routes of the Black-faced Spoonbill and identifying critical stopover sites across different life histories is vital for its conservation. However, research on the migratory routes of this species has been very limited. This study, utilizing citizen science data and the Level-order-Minimum-cost-Traversal (LoMcT) algorithm, reconstructs the migratory trajectories of the Black-faced Spoonbill from 2018 to 2022. The results show that Wenzhou, Xiamen, Shantou, Shanwei, Hsinchu, Chiayi, and Tainan are significant stopovers for this species. The Black-faced Spoonbill is actively migratory during the migration season across the southeastern coastal region of China. The simulation results of this study reveal the migratory routes and activity patterns of the Black-faced Spoonbill, providing critical support for its conservation.