Extent of this site: from the west on the upper reaches of the Wanda River and the mid and upper reaches of the Zhoushui River on the east of Aowanda. The eastern border includes the north side of Chiakan River, the upstream of the Shoufeng River. On the north, the site includes the Cross-mountain Historical Trail’s highest section on the northern slope of the Chilai South Mt. next to the Taroko National Park. To the south, the site includes the ruins of Wusuang Tribe at the upstream branches of the Chuanda River, Hayilalui Stream. The southern border of Nengdan is next to Yushan National Park.
This area penetrates deeply into the core of the Central Mountain Range, and the changes in elevation are extreme, so external communications are difficult, and the biological resources arc correspondingly better preserved in an original condition. These include very diverse ecosystem of natural forests, grasslands, and forested rivers, with these habitats of natural plant communities creating a haven for wildlife, which has experienced extremely little outside disturbance. Among these areas is Chitsai Lake at the elevation of 2900 m on the Danda forest road, which is especially mystical and attractive to people. This IBA site is considered as a sacred ground of the Atayal and the Bunan whose ancestors had been living here long time ago.
IBA A2 criterion species: Nine endemic species are commonly here: including Mikado Pheasant, White-throated Hill Partridge, Swinhoe’s Pheasant, White-eared Sibia, Steere’s Liocichla, Formosan Yuhina, Formosan Blue Magpie, Taiwan Firecrest, Formosan Barwing, Formosan Yellow Tit, Collared Bush Robin, Formosan Whistling Thrush, and Formosan Laughing Thrush.
• Because transportation to this site is very inconvenient, investigations of bird resources are incomplete. Currently Wild Bird Society of Nantou is conducting initial investigations here, and over 90 species have been recorded. In addition to the 13 endemic species, the rare or endangered species include: Besra Sparrow Hawk, Asian Crested Goshawk, Crested Serpent Eagle, Emerald Dove, Collared Owlet, Brown Hawk Owl, Collared Scops Owl, Spotted Scops Owl, White-backed Woodpecker, Grey-faced Woodpecker, Varied Tit, Melodious Laughing Thrush, Rufous Laughing Thrush and Little Forktail.
Non-bird biodiversity: • In the Nengdan area, 36 species of mammals in 8 orders and 17 families have been recorded including 12 protected species: Formosan Reeve’s Muntjac Muntiacus reevesi Micrurus, Formosan Serow Capricornis crispus swinhoei, Formosan Sambar Cervus unicolor swinhoei, Formosan Macaque Macaca cyclopis, Formosan Pangolin Manis pentadactyla, Formosan Gem-faced Civet Paguma larvata raivana, and Crab-eating Mongoose Herpestes urva.
• There are 5 species of protected reptiles and amphibians, as well the fish, Sinogastromyzon Puliensis Liang.
Pressure/threats to key biodiversity
• Protection of the natural forests has not received emphasis, and the banning of illegal cutting has not been actively pursued. In addition, the forestry agency uses inappropriate reforestation techniques, selectively cutting small-diameter trees, and planting uniform and economically important species.
• Road construction is facilitating excessive opening of cultivation and illegal cutting.
• There is illegal cultivation.
• Illegal hunting is extremely serious.
• There are pressures from recreational activities, mountain climbing, and jeep traffic that need to be controlled.
• Local aboriginals are opposed to the creation of a national park or the designation of a reserve.
Conservation responses/actions for key biodiversity
• Because the natural and cultural resources here are abundant, in April 1998, over a thousand people who fervently support ecological protection urged the establishment of the Nengdan National Park to increase conservation.
• In February 2000, the Council of Agriculture, Executive Yuan announced the Nengdan Wildlife Major Habitat, with an area of 109,952 ha. Important conservation targets are the natural forest ecosystems.