Dehing Patkai - the Rainforest of Assam in Peril
By Niranjan Nayak
Four of the total five species of globally threatened Hornbill species found in Dehing Patkai, namely Great Hornbill, Pied Hornbill, Austen's Brown Hornbill and Wreathed Hornbill.
Artwork on Stones by Niranjan Nayak
At the beginning of April 2020 as the countrywide lockdown continues, the National Board for Wildlife of India (NBWL)has approved a coal mining project in the Saleki area of the Dehing Patkai Elephant Reserve in Assam. On 7th April, NBWL’S standing committee had discussed a proposal for use of 98.59 hectares of land from Saleki proposed reserve forest land for a coal mining project by North-Easter Coal Field (NECF), a unit of Coal India Limited. The nature lovers and environmental experts alike have raised serious concerns on this move by the NBWL, fearing extensive damage that this expansion of coal mining would cause to the only rain forest existing in Assam. Let us discuss here why Dihing Patkai is unique and why sacrificing this forest to developmental needs is a wrong idea.
The Amazon of the East
The Dehing Patkai forms the largest stretch of tropical lowland rainforest of India. It falls under Indo-Burma Biodiversity Hotspot. It is also referred as “The Amazon of East” because its cover a large area of thick rainforest existing in Assam. The Dehing Patkai is located within a radius of about 25 km from the the township of Digboi, falling in Tinsukia and Dibrugarh district of Assam. It is bordered by Arunachal Pradesh in the South and covers a total area of about 111.19 sq. km of forest.
Photo: Niranjan Nayak
The name Dehing Patkai is derived from two entities, the river Dehing which runs through the natural region and from the Patkai foothills on the Southern part that connects this region with the Eastern Himalayas. It is a part of the Assam valley tropical wet evergreen forests covering a total 800 sq.km area of three combined rainforests, namely Jeypore, Upper Dehing and Dirok Rainforests. Additionally, a part situated on the South West of the region has been declared as a Wildlife Sanctuary in 2004 under the Indian Wildlife (Protection) Act 1972. The area of Dehing Patkai has several historic attractions, including World War Il cemeteries, the Stilwell’s road and the Digboi refinery.
Climate of the Area
The climate of Dehing Patkai can be termed as "Tropical Monsoon Rainforest climate with heavy monsoon downpour. The forest interiors are humid; the temperature variation might be as 10 degree Celsius in the winter nights. The temperature starts increasing from the May month reaching the peak in June and gradually fall with the downpour. The rainwater flow through the streams and sails throughout the year. There are some wetlands as well as water holes inside the forest that retain water for the whole year. Salt licks(leaks) are one of the important salt source for the wild animal of the forest.
A Rich Ecosystem
The forest of the region has a very distinctive appearance and structure dominated by its vegetation. This forest falls under tropical semi evergreen forest dominated by Dipterocarpus retusus (Holong – the state tree of Assam) which soar to a great height, along with the other canopy constructing trees interlacing with the tough and tensile lianas, the epiphytic orchids and abundant Pteridophytes growing in the living as well as dead wood. The forest floor is a home for charismatic ground orchids.
Dehing Patkai has a luxuriant ecosystem with assemblage of hundreds of species of plants from small herbs to tall trees. The different trees of the rainforest includes many species of orchid, arums, climbers, wild banana , elephant, arums and lianas found in this humid forest habitat. Some of the important tree species found in the forest area are - Hollong, Mekai, Dhuna, Udiyam, Nahar, Samkothal, Nahor, Outenga (elephant apple) different species of Ficus etc. The towering Hollong tree is the state tree of Assam.
Dehing Patkai is one of the most important places in Assam in terms of orchid diversity. There are around 107 species of orchid like Bulbophylum ebulbum, Chrysoglossum erraticum, Chrysoglossum robinsonii, Eria connate, E. pudica, Hetaeria affinis,Thelasis pygmaea, Taeniophyllum crepidiforme etc. Zeuxine clandestine was recorded for the first time in Assam at the Dehing Patkai region. The forest provides a very good environment for the survival of both the plants and animals.
Dehing patkai provides abundant resources and shelter for a variety of wildlife occupying different layers of the forest in a very complex yet delicate ecosystem. Talking about fauna, there are reports of 47 species of mammal, 50 species of snakes, 13 species of lizards, few rare and threatened turtle species, more than 350 species of butterflies etc.
Butterflies on the forest floor or Dihing Patkai. Photo: Niranjan Nayak
A globally threatened King Cobra in Dihing Patkai. Photo: Udayan Borthakur
Dehing Patkai is famous for having 7 species of primates namely rhesus macaque, Assamese macaque, pig-tailed macaque, stump-tailed macaque, slow loris, capped langur, and Western hoolock gibbon. The forest is a heaven for wildcats including tiger, leopard, clouded leopard, leopard cat, golden cat , jungle cat and marbled cat. It is one of the few areas of forest in the world which has seven different species of wildcats and globally threatened mammals like Asian elephant, gaur, Chinese pangolin, Himalayan black bear, Himalayan giant squirrel, Porcupine, Crab-eating mongoose, sambar. sun bear, barking deer, wild buffalo etc.
Female (left) and male (right) of Endangered Western Hoolock Gibbon in Dihing Patkai.
Photos: Udayan Borthakur
A Paradise for Birdwatchers
Dehing Patkai is an abode of avian diversity with more than 400 species reported so far. Studies say that a majority of about 63.7% of these bird species are residents, that means they stay in the forest throughout the year. Rest of about 23.1% bird species are winter visitors and some 2.5% are summer visitors to the forest, while about 10.7% are altitudinal migrants, coming mainly from the higher reaches of Western Central and Eastern Himalayas. Some of the important bird species found in the area includes Slender-billed vulture, White-winged Duck (State bird of Assam), Greater Adjutant Stork, Lesser Adjutant Stork, Greater Spotted Eagle, Khaleej Pheasant, Gray Peacock-Pheasant, Rufus-necked Hornbill, Pale-capped Pigeon, Brown Hornbill etc.
From left to right, Oriental Scops Owl, Golden-fronted Leafbird and Wedge-tailed Green Pigeon are amongst 400 species of birds reported from Dihing Patkai.
Photos: Udayan Borthakur
A Hub of Ethnic and Cultural Diversity
The Dehing Patkai Forest region has a rich cultural heritage. There are more than a dozen different ethnic groups living in the area including the indigenous Assamese communities, particularly Tai Phake, Khamyang, Khampti, Singpho, Nocte, Ahom, Kaibarta, Moran and Motok, Burmese, Tea-tribes (Aadivasi peoples) and Nepali people.
The Imminent Danger and Appeal for Conservation
The flora and fauna of this rainforest is far from being safe. Poaching is already danger lurking amidst the thickness of the forest. Poachers kill animals for money as well as enjoyment and even the impregnable forest of Dihing Patkai is not free from entry of such ill-minded people.
Red giant flying squirrel in Dihing Patkai. Photos: Udayan Borthakur
While I am of the opinion that people need to be made aware on the importance of these species in this rich ecosystem and how their survival can ensure longevity of the mankind. However, now Dehing Patkai faces a far greater danger than few incidences of opportunistic hunting and tree felling. We are concerned as this is happening under the patronage of the very statutory organization constituted under the India Wildlife (Protection) Act 1972.
Coal mining in Dihing Patkai Rainforests must be stopped to ensure the survival of our state bird White-wing Duck, state flower Foxtail Orchid, state tree Hollong, national animal Royal Bengal tiger and many rarer and endanger species which calls Assam a home.
Artwork by Biswajit De
About the Author:
Niranjan Nayak is a graduate student of Zoology at Digboi College of Assam and belong to Rupai siding in Tinsukia district of Assam. He volunteers for NSS India and conservation organization Aaranyak.