572 research outputs found
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Factors Influencing Distribution and Composition of Frog Assemblages in Eastern Himalaya; Implications for Conservation
No full textAmphibians are the first vertebrates to undergo profound evolutionary changes when they emerged unto land from the Devonian seas towards the end of the Paleozoic era, around 300- 350 mya, as a polyphyletic group (Jarvik 1960). There are three extant orders of amphibia, Anura (frogs and toads), Urodela (Salamanders and Newts), and Apoda (worm like burrowers) (Romer 1956; Jarvik 1960). During the process of transition from water to land, amphibians have acquired spectacular and sometimes bizarre physiological, morphological, behavioral and ecological attributes that shape their life histories. Carolus Linneaus in his seminal work Systema Naturae (1758) described amphibians as “foul and loathsome animals…… so their Creator has not exerted His power to make many of them.” In fact, Linnaeus did not distinguish between amphibians and reptiles. Being the main ingredient in the witches’ brew also added to the infamy of toads, frogs, and salamanders
The Case of Exploding Lantana and the Lessons it Can Teach Us
No full textInvasive alien species are a growing conservation problem,worldwide. There are over 200 invasive plants in India, ofwhich Lantana camara is one of the best known. This articlelooks at a brief history of Lantana’s arrival and spread acrossthe Indian subcontinent and the lessons that conservation biologistscan learn from it
The Ecological and Social Dimensions of Human-Dog-Wildlife Conflict in the Indian Trans-Himalaya
No full textHuman induced changes in food webs have altered ecosystems worldwide. Food availability from anthropogenic activities such as agriculture, livestock rearing, food production dumps, marine and terrestrial discards have been known to subsidize a range of species. In terrestrial systems, predators play a key role in shaping trophic relationships and hence it is important to understand the impact of anthropogenic subsidies on trophic connections. Amongst the terrestrial predators, domestic carnivores (dogs and cats) due to their commensal affiliations have been the prime beneficiaries of human subsidies. At a global scale, domestic dogs are the most common carnivore with a population close to a billion. Irrespective of ownership, dogs engage in free-ranging behavior which facilitates interaction with wildlife at multiple scales. Human-dog interactions also range between affiliative to agonistic. India has the fourth largest population of domestic dogs in the world (c. 60 million) and this comes at a great cost for
both wildlife and human well-being. My research aims to understand domestic dog interactions with people and wildlife and some of the repercussions of these interfaces in a resource poor environment in the Indian Trans-Himalaya
Ecosystem Services and Goods Provisioned by Fragmented Forest Landscape in a Matrix of Orange Orchards in Sikkim Himalayas, India
No full textProtected area (PA) networks help in maintaining biodiversity in large compact forest areas. However, stringent rules that exist around PAs restrict access to local communities who may be dependent on forest-based ecosystem services. Contrary to this, the increasing demands on biomass from settlements, agricultural intensification, infrastructural developments and other
human activities have resulted in the fragmentation of the forests lying outside PA networks, subsequently leading to biodiversity erosion. These changes have also put severe pressure on these forests and dramatically altered their composition, structure and ecological characteristics. These smaller and increasingly isolated fragments of natural habitats are embedded in a growing
sea of agricultural lands, pastures and urbanized areas. While these forest fragments may not support large charismatic animals, they serve as a stepping stone for species in transit moving between two PAs. Several studies in the tropics have shown that these forest fragments support a large diversity and number of insects, birds and small mammals. They have been found effective in sustaining ecosystem services such as pollination, dispersal, clean air, drinking water,
microclimate regulation, in addition to providing tangible goods such as fuelwood, fodder, edible plants, etc. that meet their daily requirements. As these ecosystem services help in maintaining human wellbeing, addressing conservation issues on domains outside formal PAs has the potential to ensure biodiversity protection as well as human wellbeing, which cannot be achieved
by setting aside forests as PAs alone. This study integrates ecology both at the local and landscape levels through ground assessments, remote sensing and social surveys, to investigate the role of forest fragments in providing ecosystem services to local communities in Sikkim Himalayas
A Comparative Study of Enumeration Techniques for Free-Roaming Dogs in Rural Baramati, District Pune, India
Full text linkThe presence of unvaccinated free-roaming dogs (FRD) amidst human settlements is a major contributor to the high incidence of rabies in countries such as India, where the disease is endemic. Estimating FRD population size is crucial to the planning and evaluation of interventions, such as mass immunisation against rabies. Enumeration techniques for FRD are resource intensive and can vary from simple direct counts to statistically complex capture-recapture techniques primarily developed for ecological studies. In this study we compared eight capture-recapture enumeration methods (Lincoln–Petersen’s index, Chapman’s correction estimate, Beck’s method, Schumacher-Eschmeyer method, Regression method, Mark-resight logit normal method, Huggin’s closed capture models and Application SuperDuplicates on-line tool) using direct count data collected from Shirsuphal village of Baramati town in Western India, to recommend a method which yields a reasonably accurate count to use for effective vaccination coverage against rabies with minimal resource inputs. A total of 263 unique dogs were sighted at least once over 6 observation occasions with no new dogs sighted on the 7th occasion. Besides this direct count, the methods that do not account for individual heterogeneity yielded population estimates in the range of 248–270, which likely underestimate the real FRD population size. Higher estimates were obtained using the Huggin’s Mh-Jackknife (437 ± 33), Huggin’s Mth-Chao (391 ± 26), Huggin’s Mh-Chao (385 ± 30), models and Application “SuperDuplicates” tool (392 ± 20) and were considered more robust. When the sampling effort was reduced to only two surveys, the Application SuperDuplicates online tool gave the closest estimate of 349 ± 36, which is 74% of the estimated highest population of free-roaming dogs in Shirsuphal village. This method may thus be considered the most reliable method for estimating the FRD population with minimal inputs (two surveys conducted on consecutive days)
Niche models inform the effects of climate change on the endangered Nilgiri Tahr (Nilgiritragus hylocrius) populations in the southern Western Ghats,India
No full textLarge mammals are declining globally due to habitat loss and fragmentation. Climate change is one of the factors
known to alter the range of several mammalian species. An early understanding of the effect of climate change
on species distributions can provide critical information for conservation planning. Nilgiritragus hylocrius (Nilgiri Tahr) is an endangered ungulate that is restricted to the montane grasslands of the Western Ghats, India.
Currently, the Nilgiri Tahr is restricted to a fraction of its former range and is also prone to risks due to several ongoing anthropogenic pressures. However, the impact of global climate change on this emblematic species has seldom been estimated. The goal of our study was to use ecological niche models to quantify the effect of climate change on the habitats of Nilgiri Tahr. Using the maximum entropy (MaxEnt) algorithm, we modelled the potential distribution of Nilgiri Tahr in its native range. The models were developed under the current climatic conditions and then projected onto two future climate change scenarios (RCP4.5 and RCP8.5) and for three different time frames in the future (years 2030, 2050 and 2080). We identified that most of the climatically suitable habitats of Nilgiri Tahr would become unsuitable when global warming intensifies. Our models predicted a complete loss of suitable habitats in many existing protected areas in the Western Ghats. We use insights provided by our modeling results to propose conservation management plans to increase the likelihood of persistence of Nilgiri Tahr in the Western Ghats
Conservation through conversation:a collaborative corridor restoration initiative in the Biligiri Rangaswamy Temple Tiger Reserve, Karnataka, India
No full textWildlife corridors are critical in maintaining ecological
processes and wildlife management, but they are fragmented and degraded due to various land-use practices. It is crucial to restore wildlife corridors through participation of communities/institutions of the landscape. Ironically, however, most of the proposed conservation plans are devoid of them in conservation and policy-making. Therefore, valuing the onus of people and their inputs to restore and manage wildlife corridors would be a practical strategy. We
are addressing this ‘restoration initiative’ in the
Biligiri Rangaswamy Temple Tiger Reserve, Karnataka,
India by integrating knowledge from social and
ecological sciences. The preliminary result indicates
that, people and institutions from the landscape are
willing to support the restoration efforts. This initiative
would emerge as one of the successful, actionoriented
and policy-driven projects in this landscap
Evaluating realized seed dispersal across fragmented tropical landscapes: a two-fold approach using parentage analysis and the neighbourhood model
No full textDespite the importance of seed dispersal for survival of plant species in fragmented landscapes, data on seed dispersal at landscape scales remain sparse. Effective seed dispersal among fragments determines recolonization and plant species persistence in such landscapes.
We present the first large-scale (216-km 2) direct estimates of realized seed dispersal of a high-value timber tree (Dysoxylum malabaricum) across an agro-forest landscape in the Western Ghats, India.
Based upon an exhaustive inventory of adult trees and a sample of 488 seedlings all genotyped at 10 microsatellite loci, we estimated realized seed dispersal using parentage analysis and the neighbourhood model.
Our estimates found that most realized seed dispersal was within 200 m, which is insufficient to effectively bridge the distances between forest patches.
We conclude that using mobility of putative animal dispersers can be misleading when estimating tropical tree species vulnerability to habitat fragmentation. This raises serious concerns about the potential of many tropical trees to recolonize isolated forest patches where high-value tree species have already been removed
Spatial and temporal distribution pattern of camptothecin in seeds and fruits of Pyrenacantha volubilis Hook.(Icacinaceae) during different fruit developmental stages
Full text linkCamptothecin (CPT), a quinoline indole alkaloid, is one of the important inhibitors of eukaryotic DNA topoisomerase I. The highest concentration of this alkaloid has been reported from the fruits of Pyrenacantha volubilis Hook. Here we report the spatial and temporal distribution pattern of CPT in seeds and fruits of P. volubilis. Temporally, CPT content
was highest in mature but unripe fruits compared to ripened fruits. Spatially, cotyledonary tissues of the seed had the highest amount of CPT followed by seed coat and fruit coat. This pattern is best explained by selection to deter fruit predators during fruit development, but attracting the fruit dispersers when fruits are mature and ripe
Sustainable Development Goal 6: watering down justice concerns
No full textThe Sustainable Development Goals (SDGs) give much greater attention to environmental concerns than the Millennium Development Goals. SDG6, the water sector goal, is also more broadly framed, as it recognizes conservation needs in addition to drinking water and sanitation. However, normatively speaking, SDG6 is still framed in adequacy and sustainability terms, downplaying the goal of justice. This is a serious lacuna. Intragenerational justice is fundamental to many environmental problems, and especially to water, because water is a common‐pool, multiple‐use and unidirectionally flowing resource. Most debates in the water sector—upstream–downstream sharing, intersectoral allocations and specifically allocation to in‐stream conservation, water pollution, and even groundwater depletion—are about the ‘biophysical (in)justice’ caused by these characteristics of the resource. The debates then focus on how the outcomes may be made more equitable (within sectors) or fair (across sectors). Large interventions, such as big dams, create multiple benefits and costs across multiple users and sectors, focusing attention on procedural justice. Social inequities may add another layer, as they often correlate with biophysical injustice. While SDG6 recognizes conservation and public health needs, it fails to recognize the fundamental tension between these needs and other uses of water, and therefore the issues of equity, fairness, and/or procedural justice in allocating between them. Policy makers may be more comfortable with framing environmental problems as sustainability problems. However, researchers have contributed to this narrowing by framing environmental problems along disciplinarily fragmented lines. The idea of biophysical justice offers an interdisciplinary bridge that may help broaden the discourse