Beijing Municipality has 20 nature reserves that have a total area of .  The mountains to the west and north of the city are home to a number of protected wildlife species including leopard, leopard cat, wolf, red fox, wild boar, masked palm civet, raccoon dog, hog badger, Siberian weasel, Amur hedgehog, roe deer, and mandarin rat snake.  The Beijing Aquatic Wildlife Rescue and Conservation Center protects the Chinese giant salamander, Amur stickleback and mandarin duck on the Huaijiu and Huaisha Rivers in Huairou District. The Beijing Milu Park south of the city is home to one of the largest herds of Père David's deer, now extinct in the wild. The Beijing barbastelle, a species of vesper bat discovered in caves of Fangshan District in 2001 and identified as a distinct species in 2007, is endemic to Beijing.  The mountains of Fangshan are also habitat for the more common Beijing mouse-eared bat, large myotis, greater horseshoe bat and Rickett's big-footed bat.