GUWAHATI: Sustained efforts for the last 13 long years since 2006 to facilitate formation of a natural canopy bridge over the railway track that bisects the country’s first hoolock gibbon protection area has finally fructified.
The much-awaited canopy bridge has come into being above the railway track inside H. Gibbon Wildlife Sanctuary in Jorhat district of Assam in the South bank of Brahmaputra River, thanks to the efforts of Jorhat Forest Division of Assam Forest Department, Primate Research & Conservation Division (PRCD) of Aaranyak, a biodiversity conservation and research organisation. The efforts for conservation of hoolock gibbon has been funded by US Fish Wildlife Service (Great Ape Conservation Fund). The N F Railway authority has extended cooperation to the project.
Hoolock gibbon has been categorized as endangered in the IUCN-red list. The Indian Wildlife (Protection) Act, 1972 put them in the list of Schedule-I species.
According to Dr Dilip Chetry, head of PRCD in Aaranyak, the railway track which was commissioned through the Gibbon habitat in 1887 divided the sanctuary into two compartments thereby posing as a barrier and threats for the wildlife, particularly for the arboreal species like hoolock gibbon.
Due to this railway track the populations of hoolock gibbon in the compartment–I lost their communication with their counterparts in compartment-II. Aaranyak came forward to bridge this canopy gap as part of its hoolock gibbon conservation programme.
A series of plantation drives was carried around the sanctuary keeping in mind the long term conservation of hoolock gibbon and other wildlife of the sanctuary. Plantation drive was carried out along the one km railway track with the help of local community. 3000 saplings of 71 species including food and lodging plants of the Gibbon, were planted in 2006 on either side of the railway track. Many of these trees were felled by the railway authority over the years. At last, a canopy bridge has formed at one point this year.
“And as we have expected gibbon, capped langur, squirrels are using this bridge regularly. The barrier created by the railway line is no more with the development of this new path of connection. This canopy bridge has rejuvenated the process of reunion of Gibbon in particular and other wildlife of compartments I and II,” Dr Chetry said.
- Gibbon Wildlife Sanctuary is the first protected area in the country where gibbon is the target species for conservation. It is situated on an area of 2098 hectare. It is an isolated forest which sustains a substantial population of hoolock gibbon.
The sanctuary is listed among the highest primate diverse areas in the country with six other species of non-human primate viz. Capped langur, Stump-tailed macaque, Pigtail macaque, Assamese macaque, Rhesus macaque and Slow loris. It is also a home to another 41 species of mammals of which 12 are schedule –I in Indian Wildlife (Protection) Act, 1972. The sanctuary is surrounded by human habitation all around.
Fragmentation of habitat has been rampant because of the bisecting railway line and anthropogenic pressures in the form of grazing, collection of fuel wood and non timber forest product (NTFP).
Out of the 20 species of gibbons, only two species namely- western hoolock gibbon (Hoolock hoolock) and eastern hoolock gibbon (Hoolock leuconydes) are found in India restricted to the tropical and sub-tropical forests of the seven states of northeast region and that to in the southern bank of the Dibang-Brahmaputra river system.
While western hoolock gibbon is found in all the seven states viz. Assam, Arunachal Pradesh, Tripura, Manipur, Meghalaya, Nagaland and Mizoram, the distribution of eastern hoolock gibbon is limited to the state of Arunachal Pradesh and Sadiya region of Assam only.