Platform Transmitter Terminals (PTTs) were fitted onto four Black-necked Cranes ( Grus nigricollis
) at Dashanbao National Nature Reserve in northeast Yunnan Province on 26 February and 1 March, 2005, to study their migratory routes and stopover sites. Of the four birds, two successfully arrived at their breeding ground in late March and early April. Of the two cranes, one completed its autumn migration in November, 2005 and spring migration in March, 2006. During spring migration, the two cranes crossed over the Jinsha River and then the Dadu River, in the upper reaches of the Yangtze River. They finally arrived in the basins of the Baihe and Heihe Rivers, in the Ruoergai Marsh in the upper streams of the Yellow River. From wintering to breeding areas, these two birds traveled 674 km and 713 km respectively, stopped at three to four sites in Sichuan Province and took three to four days to travel this distance in spring 2005. The bird that completed its fall migration in 2005 took eight days. Based on location data from the PTTs, 13 stopover sites of the four Black-necked Cranes were confirmed in Sichuan Province, with an elevation over 1 900 m above sea level. Of the 13 sites, 11 were located on riversides and the other two were by alpine lakes.