The Nilgiri Biosphere Reserve (NBR), the first of the fourteen biosphere reserves of India, was established in September 1986. It embraces the sanctuary complex of Wayanad, Nagarhole, Bandipur and Mudumalai, the entire forested hill slopes of Nilambur, the Upper Nilgiri plateau, Silent Valley and the Siruvani hills. The total area of the biosphere reserve is around 5,520 sq. km.
The Nilgiri Biosphere Reserve possesses different habitat types, unspoilt areas of natural vegetation types with several dry scrubs, dry and moist deciduous, semi-evergreen and wet evergreen forests, evergreen sholas, grasslands and swamps. It includes the largest known population of two endangered animal species, namely the Nilgiri Tahr and the Lion-tailed macaque. The largest south Indian population of elephant, tiger, gaur, sambar and chital as well as a good number of endemic and endangered plants are also found in this reserve. The habitats of a number of tribal groups remarkable for their traditional modes of harmonious use of the environment are also found here.
The topography of the NBR is extremely varied, ranging from an altitude of 250 m to 2,650 m. About 80 per cent of the flowering plants reported from the Western Ghats occur in the Nilgiri Biosphere Reserve.
Nanda Devi Biosphere Reserve
The Nanda Devi Biosphere Reserve situated in Uttarakhand includes parts of Chamoli, Almora, Pithoragarh and Bageshwar districts.
The major forest types of the reserve are temperate. A few important species are silver weed and orchids like latifolie and rhododendron. The biosphere reserve has a rich fauna, for example the snow leopard, black bear, brown bear, musk deer, snow-cock, golden eagle and black eagle.
Major threats to the ecosystem are the collection of endangered plants for medicinal use, forest fires and poaching.
Sunderbans Biosphere Reserve
It is located in the swampy delta of the river Ganga in West Bengal. It extends over a vast area of 9,630 sq. km. and consists of mangrove forests, swamps and forested islands. Sunderbans is the home of nearly 200 Royal Bengal tigers.
The tangled mass of roots of mangrove trees provide safe homes for a large number of species, from fish to shrimp. More than 170 birds species are known to inhabit these mangrove forests.
Adapting itself to the saline and fresh water environment, the tigers at the park are good swimmers, and they hunt scarce prays such as chital deer, barking deer, wild pig and even macaques. In the Sunderbans, the mangrove forests are characterised by Heritiera fomes, a species valued for its timber.
Gulf of Mannar Biosphere Reserve
The Gulf of Mannar Biosphere Reserve covers an area of 105,000 hectares on the southeast coast of India. It is one of the world’s richest regions from a marine biodiversity perspective. The biosphere reserve comprises 21 islands with estuaries, beaches, forests of the nearshore environment, sea grasses, coral reefs, salt marshes and mangroves. Among the Gulf’s 3,600 plant and animal species are the globally endangered e.g. sea cow (Dugong dugon). Besides six mangrove species, endemic to Peninsular India are also endangere.