Tens of thousands of migratory birds seen flying over wetlands of Yalu River

Tens of thousands of migratory birds have been seen flying over the wetlands of the Yalu River in Dandong City of northeast China's Liaoning Province recently. As one of the three most ideal bird-watching sites in the world, the wetlands in the Yalu River Estuary Nature Reserve attracts hundreds of thousands of migratory birds in March and April every year. Therefore, many photographers are drawn to the nature reserve.