Abstract:

The white-naped crane (Grus vipio) is listed as a vulnerable species by the IUCN. The western population of white-naped cranes continues to decline. In 2017 and 2018, we fitted 50 individuals from the western population with GPS-GSM satellite transmitters in eastern Mongolia. From July 2017 to May 2019, we obtained 48 migration routes in spring and autumn, respectively. We found that during migrations, 91.67% (spring) and 72.91% (autumn) of tracked individuals chose the Luan River upper reaches (Guyuan-Zhenglanqi-Duolun) as their stopover site, where they stayed for 36.16 ± 15.00 days (75%) in the spring, and 20.26 ± 11.08 days (67%) in the autumn. Habitat selection model showed that water (specifically distance to lake) was the main environmental variable which affects the migration route choice for white-naped cranes. The cranes preferred the stopover site that was close to lake (< 210 km) and had gentle slopes (< 1°) at an altitude between 1,200-1,500 m. The Luan River upper reaches was close to river (< 70 km) and the altitude at 1,200-1,500 m is consistent with preffered migration routes. Additionally, there are large areas of grassland and farmland for foraging and roosting. We found that there were protected areas in the Luan River upper reaches, while no more than 1.63% of the migration stopover points were within these protected areas. From our results, we argue that Luan River upper reaches was the most important stopover site for the western population of white-naped crane. Unfortunately, the cranes in this area are not well protected based on their stopover points. Therefore, we highly recommend that the Luan River upper reaches should be included as part of a conservation management system. This will be beneficial for this threatened species.

Key words: white-naped crane, migratory stopover site, the Luan River upper reaches, satellite tracking, conservation gap