Spring has returned to Wild Duck Lake in northwest Beijing's suburban Yanqing district. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]

A photo taken on April 4, 2020 shows wild ducks in Wild Duck Lake in northwest Beijing's Yanqing district. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]

Visitors cycle along the banks of Wild Duck Lake in northwest Beijing's Yanqing district on April 4, 2020. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]

Visitors arrive at Wild Duck Lake in northwest Beijing's Yanqing district on April 4, 2020. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]

Large swathes of reeds surrounding Wild Duck Lake in northwest Beijing's Yanqing district provide an ideal habitat for migratory birds. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]

Large swathes of reeds surrounding Wild Duck Lake in northwest Beijing's Yanqing district provide an ideal habitat for migratory birds. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]

A traditional pavilion on the banks of Wild Duck Lake in northwest Beijing's Yanqing district on April 4, 2020. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]

Wide-open grass fields with Haituo Mountain in the background at Wild Duck Lake in northwest Beijing's Yanqing district on April 4, 2020. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]

A wild duck swims in Wild Duck Lake in northwest Beijing's Yanqing district on April 4, 2020. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]

Large swathes of reeds surrounding Wild Duck Lake in northwest Beijing's Yanqing district provide an ideal habitat for migratory birds. The lake is the only wetland reserve for birds in Northern China and an ideal place to visit in early spring when large numbers of water birds flock to the area. [Photo by Wan Lina/China.org.cn]