Birds fly over the Yellow River estuary wetland natural reserve in Dongying, East China's Shandong Province, Oct. 19, 2013. (Xinhua/Dong Naide)
Swans swim at the Yellow River estuary wetland natural reserve in Dongying, East China's Shandong Province, Oct. 19, 2013. (Xinhua/Dong Naide)
Birds fly over the Yellow River estuary wetland natural reserve in Dongying, East China's Shandong Province, Oct. 19, 2013. (Xinhua/Dong Naide)
Tourists visit the Yellow River estuary wetland natural reserve in Dongying, East China's Shandong Province, Oct. 19, 2013. (Xinhua/Dong Naide)