Dihang-Dibang Biosphere Reserve



One of the famous Biosphere Reserves in India, the Dihang-Dibang Biosphere Reserve is located in the districts of West Siang, Upper Siang and Upper Dibang valley of Arunachal Pradesh. The reserve is counted among the few nature preserves around the world that are untouched from the modern civilisation. None of the parts of this Biosphere Reserve is reachable by road and the only way to reach there, is to walk. The reserve is comprised of a huge area of 5112 sq. km. The core zone of the reserve has area coverage of 4095 sq. km. and the buffer zone is spread over 1017 sq. km.

The Dihang-Dibang Biosphere Reserve is actually a steep terrain, combined with difficult weather as well as the lack of communication. Only about 10,000 people live in this huge area, and they are primarily from the Tribal communities like Adi, Buddhist and Mishmi. There are also ten sub-Tribes reside within the reserve, including the Pasis, Padams, Karkos, Pangis, Simongs, Ashings, Tangams, Komkars, Millangs, Dalbings, Membas, Khambas, and Idu Mishmis. On the whole, the Biosphere Reserve is almost totally forested with villages and cultivations located on the lower slopes and terraces edging the major rivers systems. In some parts of the reserve, the forest appears as a continuous swath from the sub-tropics to the cold of the tree line. Apart from that, a large area of the Reserve also lies at elevations above the tree line and this area features a very special array of plants and animals. The Reserve exhibits a wonderful extent of sub-tropical forest.

Orchid The Dihang-Dibang Biosphere Reserve has quite rich natural vegetation. The vegetation in this reserve varies according to habitat. Altitude is one of the major factors in determining plant growth, as the altitude of the Reserve varies from approximately 500 to 6000 meters (with associated temperatures and rainfall variability). Apart from altitude, there are also some other factors in determining the plant growth, including the varying soils and differing exposures. Some of the major microhabitats in this Reserve include the snow peaks (with algae in the snow and lichens on exposed rocks), glacial lakes, forest ponds, stream edge habitat, etc. The Reserve represents more than 8 forest or vegetation types like the Sub-Tropical Broad Leafed, Sub-Tropical Pine, Temperate Broad Leafed, Temperate Conifer, Sub-Alpine Woody Shrub, Alpine Meadow, Bamboo Brakes, and Grass Lands.

The Dihang-Dibang Biosphere Reserve constitutes a part of one of the "Biodiversity Hot Spots" in the world. The reserve is home to approximately more than 1500 species of flowering plants. The area is also possible to be the centre of origin for some common crop plants like Banana. Apart from that, several NTFP and economic plant groups can also be found here that include the medicinal, aromatic, timber, fodder and fuel plants. The most common ornamental plants found in this reserve include the Orchids, Rhododendrons and Primulas. The reserve is home to the rare Orchid, Vanda stangeana, along with over 50 species of Rhododendrons. The area also provides shelter for saprophytes like Monotropa uniflora, Epipogium spp., and Gastrodia sp; and the Parasitic plants like Balanophora sp., Boescheckia sp., Galeola sp., etc. Apart from these, some plants belonging to the "primitive" families are also seen here. These plants include Mangletia gaveana, Magnolia campbellii, Schizandra neglecta, Holbelia latifolia, and various species of Ranunculus, etc. Some of the very rare and endangered plant species found in the Dihang-Dibang Biosphere Reserve include the Cyathea sp., Angiopteris sp., Livingstonia sp., Coptees teeta and Amenototaxus sp., etc.

Marbled Cat Apart from the rich variety of natural vegetation, the Dihang-Dibang Biosphere Reserve also provides natural habitat to numerous fauna species. Some of these fauna species are endemic to the eastern Himalayas and many of these and others are considered as endangered. About 45 species of insects including Moths and Butterflies are found in the reserve and the collection of amphibians in the reserve is also great. However, the reserve is not that much rich in providing habitat to the reptiles. A wonderful cross-section of Asian Snakes can be found in the reserve. Though most of these snakes are the non-poisonous members of the Colubridae family, some poisonous snakes are found here, as well. These species include the Green Pit Vipers, Cobras (Naja and Ophiophagus) and Kraits. The Indian Rock python is also found here.

The Dihang-Dibang Biosphere Reserve is home to a rich variety of mammal species. Several members of the Cat family like Tiger, Spotted or Common Leopard, Clouded Leopard, Snow Leopard, Golden Cat, Jungle Cat, Marbled Cat, Leopard Cat, etc. can be found in different elevations in this reserve. The other important mammal species found in the Biosphere Reserve include Blue Sheep, Red Panda, Takin, Musk Deer, Bison, Serow, Himalayan Black Bear, Sloth Bear, Indian Wild Dog, Red Fox, Deer, Assamese Macaque, Otter (both common & clawless), Squirrel, Civet, Wild Boar, etc.

Apart from the rich variety of natural vegetation and mammal species, the Dihang-Dibang Biosphere Reserve also provides natural habitat to numerous bird species. Till 1997, about 195 species of bird had been recorded in the reserve. The very much threatened species like Sclater`s Monal and Blyth`s Tragopan are among the most interesting of these species. Apart from these, some of the other important bird species found in the Biosphere Reserve include the Temminck`s Tragopan, Pale-Capped Pigeon, Purple Cochoa, Nepal Cutia, Pale Blue Flycatcher, Wedged Billed Wren-Babbler, Water Pipit, Japanese Bush Warbler, Isabeline Wheatear, Black Faced, Chestnut-Eared, Pine Buntings, etc. There is also a possibility to find the Rufous-Tailed Babbler in the Dihang-Dibang Biosphere Reserve.

The reserve also shares the record for low population densities with places like the Changtang Reserve in Tibet and the Gobi reserves in Mongolia. The reserve has a population density of only 2 people per sq. km. On the whole, the Dihang-Dibang Biosphere Reserve is indeed one of the most unique and valuable biosphere reserves in India.

  Pale-Capped Pigeon, Purple Cochoa, Nepal Cutia, Pale Blue Flycatcher, Wedged Billed Wren-Babbler, Water Pipit, Japanese Bush Warbler, Isabeline Wheatear, Black Faced, Chestnut-Eared, Pine Buntings, etc. There is also a possibility to find the Rufous-Tailed Babbler in the Dihang-Dibang Biosphere Reserve.

The reserve also shares the record for low population densities with places like the Changtang Reserve in Tibet and the Gobi reserves in Mongolia. The reserve has a population density of only 2 people per sq. km. On the whole, the Dihang-Dibang Biosphere Reserve is indeed one of the most unique and valuable biosphere reserves in India.

Flora: The vegetation varies according to habitat. Various factors like climatic, edaphic and biotic factors attributes the condition of forming such habitat. The BR has an altitudinal  range from 500 to 6000 mtr and a major factor in determining the plant community. The type of vegetation can such be grouped as    1. Sub-tropical broad leafed forests.     2. Sub-tropical pine forest.     3. Temperate broad leafed forests.    4. Temperate conifer.     5. Sub-alpine woody shrub.     6. Alpine meadow (Mountain tundra)    7. Bamboo brakes.     8. Grass lands.

The Biosphere Reserve forms a part of one of the world’s “Bio-Diversity Hot spots”. Tremendous speciation occurs here with over 1500 species of flowering plants expected. Possibly this site may be the center of origin for some crop plants such as the banana. Many NTFP and economic plants groups occur here. Medicinal, aromatic, timber, fodder and fuel plants could be mentioned. There is a rich representation of orchids, Rhododendrons and Primulas. The rare orchid, Vanda strangeana, lives here as do over 50 species of rhododendrons. For the some plant genera and families, this area may be a part of where they initially diversified (i.e. the cradle of speciation). The Rhododendrons genus may be thought of in this context. The BR provides the rich for all organisms like saprophytes, as Monotropa uniflora, Epipogium spp and Gastrodia spp and parasites such as Boescheckia spp, Galeola spp. Some plants listed in “primitive” families are seen here including Mangletia gaveana, Magnolia campbettii, Schizandra neglecta, Holbelia lotifolia, and various species of Ranunculus. Only a few of the many rare and endangered species here include cyathea spp, Angiopteris spp, living stonia spp, Coptus teeta and Amenototaxus spp. Local medical healers have a remarkable storehouse of knowledge relating to their environment and thus the BR has an important socio-economic signature due to its ethno-biological richness.

Fauna: This BR is very rich and diverse in the population of animal. Some of the species here are endemic to the eastern Himalayas, many of these as well as others are listed at endangered. Some of the spcies as recorded are insects of 45 species including moths and butterflies wre documented Hill trout has been observed among the fishes. There is an impressive array of forest frogs. It is noticed that a wonderful chorus of frogs at some part of the BR forests breaks out just after the dark, often with four or more species calling at the same time. Snakes are present there, mostly non-poisonous except the poisonous green pit vipers (Trimeresurus), cobras (Naja and Ophiophagus) and kraits (Bungarus). The Indians rock python is also known. About 195 species of birds had been recorded. Of these, the scatter’s Monal and Blyth’s Tragopan are among the most interesting. These beautiful pheasants live in a limited range of the eastern Himalayas and are very much threatened. Temminck’s trogopan is also found in this region but no data on this bird is available from the Indian sub-continent. The pale-capped pigeon a globally threatened spp is recorded in this area. Other species, considered rare in parts of the Himalayas, have been found to be comparatively common here. These include the Purple cochoa, Nepal cutia, and Pale Blue Flycatcher. The wedged billed wren babbler family (Timaliidac), has been seen here. Some more interesting observation has been make and these include the water pipit, Japanese Bush warbler, Isabeline wheatear, Black faced, chest nut earned and pine buntings. In addition there is a possible sighting of the Rufous tailed babbler, crysomma poecilvtis, a species new to the Indian sub continent.

The distribution of large animals like tiger is as 1. Tiger is found at lower elevation       2. Spotted or common leopard in with in the range from the tropics to the tree line    3. Clouded Leopard in wet forests at moderate elevations to the snowline and    4. Snow Leopard above the tree line on slopes where blue shup live.    Small cats also occur here. The entire north boundary of the BRs the home of elusive and shy Red Panda. One of the most unusual ungulates of the eastern Himalayas and Western Chinese mountains is the Takin. This animal occurs here in small herds that range from 2500 to 4000 mtrs. The endangered Musk Deer also lives at these elevations but is confined to forest. Other includes Bison, Serow, Himalayan Black Bear, Sloth bear, Indian Wild dog, Red fox, Deer, Assamese Macaque, Squirrel, Civet and Wild Board.  With such diverse biological potential, spread over more that 5,000 Sq.km of different bio-zones, the proposed BR is truly a biologist’s dreamland. The tribal population inhabiting this area are in harmony with their environment and have for generations been utilizing their rich bio-diversity for their sustenance.

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