NANCHANG -- A number of white cranes have been spotted at Poyang Lake in eastern China's Jiangxi province, marking the start of the migratory birds' wintering in China's largest freshwater lake this year.

At 10:45 am on Monday, one white crane was observed at the lake. Another 17 were spotted at 2:30 pm, according to staff with the Jiangxi Poyang Lake National Nature Reserve Administration.

Apart from white cranes, white-naped cranes, grey cranes, oriental white storks, and other species of migratory birds have also arrived at the lake.

White cranes are also known as "living fossil" birds, with only about 4,000 in the world. Every year at the end of autumn and the beginning of winter, they fly to the lake for the winter, mainly foraging in shallow water. From late February to early March the following year, large flocks begin to fly northward.

Poyang Lake is an important wintering area for waterbirds in Asia. Each year, hundreds of thousands of birds from Russia, Mongolia, Japan, and the Democratic People's Republic of Korea, as well as China's northwest and northeast quarters, winter at the lake.