|Habitat outside Assam’s protected zone shrinks|
Guwahati, June 17: Outside Assam’s vast protected area network, grasslands offer a slim hope of supporting threatened species.
Now, 3.1 per cent of the total landmass of Assam is covered by grasslands but most of it have suffered a rapid decline with the encroachment of civilisation in the form of agriculture, livestock grazing, irrigation and urbanisation.
Till the late 19th century, almost three-fifth of the landmass of the Brahmaputra valley was grasslands.
“Outside the protected area there is no extended and quality grasslands which can support threatened species,” Bibhuti Lahkar, grassland specialist with Aaranyak, a premier society for bio-diversity conservation in the Northeast, said.
The plains in Assam have some of the last remaining alluvial grasslands, which were once widespread in India and lowland Nepal. These grasslands support at least 15 species of globally threatened birds, apart from mammals and reptiles.
Manas tiger reserve serves as one of the remaining protected areas where grassland-dependent endangered species like tiger, pygmy hog, hispid hare, water buffalo, elephant and rhinoceros can be located. Unfortunately, the grasslands in Manas are also shrinking and nearly 11 per cent to 12 per cent of it is gone.
“Livestock grazing should be stopped. Existing grasslands should be protected from further degradation and there should be a grasslands conservation policy for Assam,” Lahkar said.
Despite the fact that grassland habitats are shrinking at an alarming rate in the Indian subcontinent, very little attention has been paid at both national and international levels for the conservation and management of the grasslands ecosystem.
Invasive species in the grassland habitats is a major concern in recent years but very few studies have been initiated on this issue. The invasion of mimosa has emerged as a major threat in Kaziranga National Park. The principal invasive species in the grasslands of Assam are- Mimosa diplotricha (Kaziranga, Orang), Mikania micrantha (Manas, Kaziranga, Orang), Chromolaena odorata (Manas, Orang) and Ipomea carnea (Pobitora).
“Officials must have a thorough knowledge and understanding of the specific habitat requirement of different threatened or specialist species. This will help in understanding how a specific species of birds responds to fire and disturbance factors like grazing, encroachment and even floods,” Lahkar added.