The Migration Route And The Stopover Sites Of The Eastern Population Of The Black-necked Crane (Grus Nigricollis)

In this thesis, we study the migration of the eastern Population of the Black-necked Craneon its migration routes, stopover sites, and the weather affecting their migration.In 2006, we harnessed 4 satellite transmitters on 4 Black-necked Cranes respectively totrack the migration route and stopover sites of the eastern group of Black-necked Cranewintering at Dashanbao National Nature Reserve of Yunnan Province and Caohai NationalNature Reserve of Guizhou Province. Three of the four tracked Black-necked Cranes havefinished twice spring migration and once fall migration, the other only finished one springmigration and one fall migration.In spring, after departing from the two nature reserve for wintering, Dashanbao of Yunnanprovince or Caohai of Guizhou province, the eastern population of the Black-necked Crane flyacross Jinsha River, and get across or stop at Sichuan Liangshan Mountains in northwestdirection, then, they fly to the location which is the boundary of Liangshan Mountains, Qionglai Mountains and Big Snow Mountains. Finally, along Dadu River northward, they getto Ruoergai Swamp, the breeding ground of the Black-necked Crane.In fall, the migration route is generally the same with the route in spring. TheBlack-necked Cranes spend 6.7 days averagely in their spring migration and 5.5 days in theirfall migration. The migration distance averagely is about 725.4km in their spring migration and903.6km in their fall migration. We think that the Black-necked Cranes adopt "TimeMinimization Strategy" in their migration either in spring or in the fall.Temperature is one of the most important factors of weather when Black-necked Cranestart migration. Black-necked Cranes usually start migration when temperature reaches over8.1℃in spring, and temperature below -10℃in the fall. Beside the temperature, the speedand direction of wind also affect greatly the migration of Black-necked Crane. Black-neckedCranes prefer to propitious winds or gentle breeze when they migrate, and would rathersunshine than rain during migration.We have found 65 times' stopover of tracked 8 Black-necked Crane between RuoergaiSwamp and Yungui Plateau during migration, which rest at 33 sites in the routes after two-year satellite tracking research.. We discovered that most of the stopover sites locate on top ofmountains, the characteristics of these stopover sites are flat grasslands with streams or pondsaside and few human disturbance. These stopover sites distribute within the range of 66villages and towns of 23 counties in Sichuan Province, and about 60 percent of the sites are outof protection areas. Comments and suggestions are expressed based on the results of ourresearch for the protection of important stopover sites of Black-necked Crane.