Impacts of climate changes on the potential habitat suitability of Grus japonensis on migration routes

In the context of global warming and human disturbances, many habitats of endangered waterfowl on migration routes have been threatened. Due to the limits in monitoring methods and technologies, the potential habitat quality of Grus japonensis on its migration routes is understudied. The impact of climate changes on the habitat suitability of these species requires further investigation. In this study, an ensemble species distribution model was constructed based on 174 occurrence samples and 10 habitat features to assess the habitat suitability of Grus japonensis on migration routes in eastern Asia. We also predicted the changes in the suitable habitat areas of Grus japonensis in 2060 and 2100 under two future climate scenarios (SSP2-4.5 and SSP5-8.5). The results showed that the ensemble species distribution model achieved a higher accuracy in mapping potentially suitable habitats of Grus japonensis compared with the single species distribution models. The area under curve (AUC) value, true skill statistics (TSS) value, and Kappa coefficient were determined as 0.98, 0.94, and 0.96, respectively. At present, the total area of suitable habitats of Grus japonensis on the migration route of eastern Asia is approximately 3.95 x 105 km2. Under the intermediate greenhouse gas (GHG) emission scenario (SSP2-4.5), the area of suitable habitats on the migration route is predicted to decrease to 3.67 x 105 km2 by 2100, with a reduction rate range from 7.34 % to 13.92 %. Under the very high GHG emission scenario (SSP5-8.5), the area of suitable habitats on the migration route is predicted to decrease to 3.65 x 105 km2 by 2100, with a reduction rate range from 11.13 % to 14.43 %. This study is important for simulating the habitat suitability of endangered waterfowl on migration routes. It also provides key decision support for the conservation and restoration of the potential habitats for endangered waterfowl.