The Sanggan River National Wetland Park in Shanyin County, Shanxi Province, has welcomed thousands of swans. Some soar through the sky, others frolic on the water, while many rest along the riverbank. Meanwhile, Dongyulin Reservoir along the Sanggan River has seen dozens of white and black storks. Local officials say during this year's migration season, the reservoir has seen more than 50,000 migratory birds, including over 20 nationally protected species.