More than 400 red-crowned cranes and other migratory birds have recently flocked to the Yellow Sea wetland in Yancheng Wetland Rare Birds National Nature Reserve in east China's Jiangsu Province for wintering. 

The wetland has also welcomed the arrival of oriental storks, black-faced spoonbills, and grey cranes. 

The first group of red-crowned cranes arrived on December 28th. The population of grey cranes is about 10,000, and the population of birds in the anatidae family and cormorants is around 20,000.  

The birds that stay at the wetland could reach a total of three million in the winter. 

As an important habitat for migratory birds, the Yellow Sea wetland in Yancheng was added to the World Heritage List of the United Nations Educational, Scientific, and Cultural Organization last July. 

The migratory birds will stay here for nearly half a year. The reserve will take steps to ensure the birds are well protected during their stay. 

"We have strength up the patrol, especially the night patrol. Secondly, we are working with the public security department to enhance law enforcement on wild animal poaching. Thirdly, we have enough feed for birds for wintering, to avoid any bird food shortages caused by abrupt weather changes," said Chen Guoyuan, head of the Dongsha Station of the Yancheng Wetland Rare Birds National Nature Reserve. 

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