Study on habitat suitability change and habitat network of rare wintering cranes in important international wetlands

•The role of ecological corridors in the protection of rare waterbirds.•Ecological network analysis based on graph theory.•Gravity model screening important connection corridors.•Use MCR theory to find the best migration sites for rare waterbirds.•Important habitat area of rare headed crane mainly in beach. Chongming Dongtan wetland is a typical estuarine wetland, located in Chongming District, Shanghai, China, with high ecological significance. The protection of wintering crane's habitat has attracted the wide attention of the international community. Because of the importance of the region in the protection of international biodiversity and the protection of crane habitats, it is of great reference value to study the habitat suitability changes of rare wintering cranes with spatial and temporal distribution characteristics and the distribution of habitat corridors with spatial characteristics, to improve the habitat quality of crane habitats in globally important wetlands. Based on the remote sensing image data of Chongming Dongtan and the field survey data of rare wintering cranes, this study obtained the land use change of Chongming Dongtan from 1986 to 2021 by ENVI and ArcGIS10.8 software, evaluated the habitat suitability of wintering cranes in 36 years by GIS technology, and constructed the habitat corridor of wintering cranes by using the minimum cumulative resistance model(MCR). The results showed that from 1986 to 2021, the number of four typical wintering cranes in Chongming Dongtan showed a general downward trend. In the past 36 years, the habitat suitability of wintering cranes in the internationally important wetland of Chongming Dongtan has gradually changed from a suitable area to an unsuitable area. The suitable areas are mainly distributed in the eastern and northern parts of the study area, and the unsuitable areas are mainly distributed in the western construction land area. The habitat quality of cranes is deteriorating. The overall resistance distribution of Chongming Dongtan in 2021 shows a trend of low resistance value in the east and high resistance value in the west, and the degree of obstruction is strong in the south and weak in the north. There are 208 potential habitat corridors for wintering cranes in Chongming Dongtan, with a total length of 377.12 km. Get 127 Habitat nodes. The density of habitat corridors in the eastern part of the study area is significantly higher than that in the western region, and the ecological space