Milu deer, a species native to China, was declared extinct in the wild in China during the early 20th century. In 1985, China began reintroducing the species through cooperation with the United Kingdom. By 1986, another batch was released into what is now the Dafeng Milu National Nature Reserve in Jiangsu Province. Since then, the milu population in China has surged from several dozen individuals to around 15,000, including more than 6,000 now living in the wild – the largest wild milu population in the world.

After 40 years of breeding, habitat restoration and careful conservation, China has re-established its wild populations of milu deer, making the species one of the world's most remarkable wildlife recovery stories.