(Photo: CGTN)

As temperatures rise in the northern parts of China, black-necked cranes are starting to make their way back after having spent the winter in the warm south. 

Every year, thousands of black-necked cranes migrate to Caohai National Nature Reserve in southwest China's Guizhou Province to spend the long cold winter. As soon as the weather starts to warm up, they fly back to their nesting grounds in the north. 

"If they plan to migrate the next day, they will fly and hover in the sky to observe the weather. If the weather conditions are fine and the southerly wind blows, they will ride the wind all the way to the north," said Zhao Qingjun, a ranger at the Caohai National Nature Reserve.

According to statistics, about 1,650 black-necked cranes spent the past winter in Caohai, of which more than 600 had already returned to the north.

Meanwhile, in Aba Tibetan and Qiang Autonomous Prefecture, southwest China's Sichuan Province, five black-necked cranes were spotted arriving at the Hongyuan Prairie on Monday. 

With an altitude of 3,535 meters above sea level, the Hongyuan Prairie is a place where black-necked cranes must pass during their migration. The five cranes are the first ones in this season to arrive in the prairie.