Alumnus, Western Ghats
Ph D, National Institute of Advanced Studies and Manipal University
M Sc, Zoology, Department of Zoology, Gauhati University
B Sc, Zoology, B. Borooah College, Gauhati University, Guwahati
I study community and behavioural ecology and the conservation biology of the primates in the fragmented landscape of Upper Brahmaputra Valley of northeastern India. I am also interested in political , human and landscape ecology as well as ecological history. Currently, I am part of a collaborative project entitled ‘Landscape level conservation planning for elephants in Karnataka’. I am collating data on the distribution of elephants, their habitats, and on anthropogenic factors affecting elephant distribution from across the state, and to assist with the delineation of elephant habitats, respectively, into conservation, co-existence and removal zones, based on objective ecological and social criteria.
- Journal Article2015White-winged Duck Asarcornis scutulata in Hollongapar Gibbon Sanctuary, AssamIndian BIRDS 10:121-123
- Journal Article2015Distribution, relative abundance, and conservation status of Asian elephants in Karnataka, southern IndiaBiological Conservation 187:34-40Download
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Karnataka state in southern India supports a globally significant—and the country’s largest—population of the Asian elephant Elephas maximus. A reliable map of Asian elephant distribution and measures of spatial variation in their abundance, both vital needs for conservation and management action, are unavailable not only in Karnataka, but across its global range. Here, we use various data gathered between 2000 and 2015 to map the distribution of elephants in Karnataka at the scale of the smallest forest management unit, the ‘beat’, while also presenting data on elephant dung density for a subset of ‘elephant beats.’ Elephants occurred in 972 out of 2855 forest beats of Karnataka. Sixty percent of these 972 beats—and 55% of the forest habitat—lay outside notified protected areas (PAs), and included lands designated for agricultural production and human dwelling. While median elephant dung density inside protected areas was nearly thrice as much as outside, elephants routinely occurred in or used habitats outside PAs where human density, land fraction under cultivation, and the interface between human-dominated areas and forests were greater. Based on our data, it is clear that India’s framework for elephant conservation— which legally protects the species wherever it occurs, but protects only some of its habitats—while being appropriate in furthering their conservation within PAs, seriously falters in situations where elephants reside in and/or seasonally use areas outside PAs. Attempts to further elephant conservation in production and dwelling areas have extracted high costs in human, elephant, material and monetary terms in Karnataka. In such settings, conservation planning exercises are necessary to determine where the needs of elephants—or humans—must take priority over the other, and to achieve that in a manner that is based not only on reliable scientific data but also on a process of public reasoning.
- Popular Article2014At a crossroadsThe Hindu in School, 10 September
- Journal Article2014Local and Landscape Correlates of Primate Distribution and Extinction in Upper Brahmaputra ValleyConservation Biology 28(1): 95-106Download
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Habitat fragmentation affects species distribution and abundance, and drives extinctions. Es- calated tropical deforestation and fragmentation have confined many species populations to habitat rem- nants. How worthwhile is it to invest scarce resources in conserving habitat remnants within densely settled production landscapes? Are these fragments fated to lose species anyway? If not, do other ecologi- cal, anthropogenic, and species-related factors mitigate the effect of fragmentation and offer conservation opportunities? We evaluated, using generalized linear models in an information-theoretic framework, the effect of local- and landscape-scale factors on the richness, abundance, distribution, and local extinction of 6 primate species in 42 lowland tropical rainforest fragments of the Upper Brahmaputra Valley, northeastern India. On average, the forest fragments lost at least one species in the last 30 years but retained half their original species complement. Species richness declined as proportion of habitat lost increased but was not significantly affected by fragment size and isolation. The occurrence of western hoolock gibbon (Hoolock hoolock) and capped langur (Trachypithecus pileatus) in fragments was inversely related to their isolation and loss of habitat, respectively. Fragment area determined stump-tailed (Macaca arctoides) and northern pig-tailed macaque occurrence (Macaca leonina). Assamese macaque (Macaca assamensis) distribution was affected negatively by illegal tree felling, and rhesus macaque (Macaca mulatta) abundance increased as habitat heterogeneity increased. Primate extinction in a fragment was primarily governed by the extent of divergence in its food tree species richness from that in contiguous forests. We suggest the conservation value of these fragments is high because collectively they retained the entire original species pool and individually retained half of it, even a century after fragmentation. Given the extensive habitat and species loss, however, these fragments urgently require protection and active ecological restoration to sustain this rich primate assemblage.
- Popular Article2013Three different voicesThe Hindu in School, 17 July
- Journal Article2012Trends in extinction and persistence of diurnal primates in Upper Brahmaputra ValleyOryx 46(2): 308-311Download
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The historical deforestation of the Upper Brahmaputra Valley in the Indian state of Assam has resulted in the transformation of its once-contiguous lowland rainforests into many isolated forest fragments that are still rich in species, including primates. We report the recent history and current status of six diurnal primates in one large (2,098 ha) and three small (, 500 ha) fragments of the Upper Brahmaputra Valley. We censused primates in the small fragments during 2002, 2005, 2009, in the large fragment in 2008, and used other published census data to derive population trends. We also used key informant surveys to obtain historical occurrence data for these populations. Our analyses reveal the recent extinction of some populations and the simultaneous long-term persist- ence of others in these fragments over 16 years. Most populations appeared to have declined in the small fragments but primate abundance has increased signific- antly in the largest fragment over the last decade. Addressing the biomass needs of the local human populations, which appears to drive habitat degradation, and better protection of these forests, will be crucial in ensuring the future survival of this diverse and unique primate assemblage in the last rainforest fragments of the human-dominated Upper Brahmaputra Valley.
- Popular Article2012The singing farmers of the forestThe Hindu in School, 21 November
- Journal Article2012Socio-economic drivers of Forest Cover Change in Assam: A Historical PerspectiveEconomic and Political Weekly 47(5): 64-72Download
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This article analyses the historical context of forest cover change in the upper Brahmaputra Valley of Assam during the precolonial, colonial and the postcolonial periods, locating these changes within the political economy and demographic milieu of each regime.In the current context of rising populations linked to immigration from neighbouring regions, dwindling share of agriculture in the state’s gross domestic product, and recent incentives to small tea growers in risk-prone agricultural landscapes, serious challenges remain to securing forests in this region. Empowering local communities and institutions, understanding tea plantation dynamics and managing the causes and consequences of recent demographic change are crucial to the conservation of forests there.
- Thesis2012Primate on the edge: Ecology and Conservation of Primate Assemblages in the Fragmented Lowland Rainforests of the Upper Brahmaputra Valley, Northeastern IndiaPhD Thesis submitted to Manipal University, Manipal, Karnataka
- Popular Article2011A remnant taleSanctuary Asia 31 (5):42-47Download
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Natural history of the stump-tailed macaque, one of India’s least- known primates that is holding on for dear life in Assam’s tiny but rich Hollongapar Gibbon Wildlife Sanctuary.