More than 1,400 black-necked cranes — about one-sixth of the species' global population — came to the Dashanbao National Nature Reserve to spend the winter this year, according to sources at the reserve in Zhaotong, Yunnan province.

The reserve is a major wintering habitat for the birds, which are under first-class state protection. It counted only about 300 black-necked cranes when it was established in 1990.

The cranes have begun to fly north and are expected to complete their migration soon. They will fly as far as 800 kilometers, eventually reaching the Zoige Prairie in Sichuan province, where they will breed.