More than 53,000 migratory birds, including precious black-necked cranes, have arrived at a national nature reserve in Southwest China's Guizhou province to start this year's wintering, local authorities said Tuesday.

Caohai National Nature Reserve, located in Weining county at an altitude of 2,100 meters, accommodates over 100,000 migratory birds every winter.

As of Monday, 1,325 black-necked cranes, 567 gray cranes, 1,570 bar-headed geese, 17,900 Eurasian coots and 32,260 other birds have been spotted in the reserve, according to the management committee of the nature reserve.

It is expected that the number of migratory birds spending winter in the nature reserve will reach its peak in January.

Black-necked cranes are under the highest level of national protection in China. Staff with the management committee of the reserve have strengthened patrols to ensure their safety. Patrollers will watch over the birds in different habitats at the reserve, said Liu Guanghui, a patroller.

The management committee has also strengthened construction of the foraging sites of the migratory birds to ensure the birds have enough food, said Li Zhenji, deputy director of the environmental monitoring branch under the committee.

In order to protect the biodiversity of Caohai, Weining county will strengthen the comprehensive management of the reserve and constantly improve the level of protection and management.

"This year, rowing is banned in Caohai, giving the birds a wider space to live in," Li said.