Caohai Plateau Wetland, located in Bijie, southwest China’s Guizhou province, is a national nature reserve. As the winter comes, the first batch of migratory birds - the black-necked cranes - have arrived there to pass the winter. As a large number of migratory birds choose Caohai wetland as winter habitat, the place is regarded as one of the best bird watching places in the world. (Photo/people.cn)