Platform Transmitter Terminals (PTTs) were fitted onto four Black-necked Cranes (Grus nigricollis) at Dashanbao National Nature Reserve in Northeast Yunnan in the spring of 2005. Two of the four birds completed the whole migration, while the other two lost their signals on the half way. Of the two birds that completed their migration, they started to migrate on 4th and 6th of April respectively and arrived at the breeding ground Ruoergai Marsh within 3-4 days, traveling 700-740 km, and stopping at 4 counties in Sichuan Province.