Located in the easternmost coast of Shanghai's Chongming Island, the largest alluvial estuary island in the world, the Dongtan Wetland is a paradise for migratory birds. It is situated in the middle of one of the world's eight major migration routes for migratory birds and serves as a key stopover and habitat for them. Each year, nearly one million migratory birds arrive there for temporary stays or wintering.
So far, 300 bird species have been recorded at the wetland, including 20 that are on the red list of endangered species. To protect this valuable natural resource, a nature reserve was set up at the wetland in 1999 and in 2005 the Shanghai Chongming Dongtan National Nature Reserve was officially established.