The marshes of the Hongyuan-Ruoergai Plateau in northern Sichuan were visited between 27 May and 10 June 1991 to determine the status there of Black-necked Cranes Grus nigricollis, to investigate reports of threats to their habitat from peat-mining, and to consider options for a protected area for the cranes. Almost 80,000 ha of wetlands in Ruoergai County were surveyed, as well as some of the contiguous wetlands in northern Hongyuan County; 240 Black-necked Cranes and 24 active nests were located. Between 600 and 900 cranes were estimated to be present on the plateau, making this the most important breeding and summering area for the species hitherto known. Neither peatmining nor hunting was judged to pose a threat to the cranes. The principal threat is drainage of habitat for pastureland: overgrazing by domestic livestock is a serious problem on the grasslands, and some drainage of bogs has already occurred in an attempt to increase the area of grazing land. The establishment of a large “crane conservation area” has been proposed, in which there would be no restrictions on the traditional activities of the local tribespeople, but where large-scale drainage, peat-mining and other development activities likely to have a negative impact on the wetlands would be prohibited.