Foundation for Ecological Research

Vazhakulam, India

Foundation for Ecological Research

Vazhakulam, India
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Gangadharan A.,University of Alberta | Gangadharan A.,Foundation for Ecological Research | Vaidyanathan S.,Foundation for Ecological Research | St. Clair C.C.,University of Alberta
Journal for Nature Conservation | Year: 2017

Connectivity for large mammals across human-altered landscapes results from movement by individuals that can be described via nested spatial scales as linkages (or zones or areas) with compatible land use types, constrictions that repeatedly funnel movement (as corridors) or impede it (as barriers), and the specific paths (or routes) across completely anthropogenic features (such as highways). Mitigation to facilitate animal movement through such landscapes requires similar attention to spatial scale, particularly when they involve complex topography, diverse types of human land use, and transportation infrastructure. We modeled connectivity for Asian elephant (Elephas maximus) and gaur (Bos gaurus) in the Shencottah Gap, a multiple-use region separating two tiger reserves in the Western Ghats, India. Using 840 km of surveys for animal signs within a region of 621 km2, we modeled landscape linkages via resource selection functions integrated across two spatial resolutions, and then potential dispersal corridors within these linkages using circuit theoretical models. Within these corridors, we further identified potential small-scale movement paths across a busy transportation route via least-cost paths and evaluated their viability. Both elephants and gaur avoided human-dominated habitat, resulting in broken connectivity across the Shencottah Gap. Predicted corridor locations were sensitive to analysis resolution, and corridors derived from scale-integrated habitat models correlated best with habitat quality. Less than 1% of elephant and gaur detections occurred in habitat that was poorer in quality than the lowest-quality component of the movement path across the transportation route, suggesting that connectivity will require habitat improvement. Only 28% of dispersal corridor area and 5% of movement path length overlapped with the upper 50% quantile of the landscape linkage; thus, jointly modeling these three components enabled a more nuanced evaluation of connectivity than any of them in isolation. © 2017 Elsevier GmbH

Ramachandran R.,Tata Institute of Fundamental Research | Ramachandran R.,Nature Conservation Foundation | Kumar A.,Tata Institute of Fundamental Research | Kumar A.,Center for Wildlife Studies | And 3 more authors.
Ambio | Year: 2017

The relative impacts of hunting and habitat on waterbird community were studied in agricultural wetlands of southern India. We surveyed wetlands to document waterbird community, and interviewed hunters to document hunting intensity, targeted species, and the motivations for hunting. Our results show that hunting leads to drastic declines in waterbird diversity and numbers, and skew the community towards smaller species. Hunting intensity, water spread, and vegetation cover were the three most important determinants of waterbird abundance and community structure. Species richness, density of piscivorous species, and medium-sized species (31–65 cm) were most affected by hunting. Out of 53 species recorded, 47 were hunted, with a preference for larger birds. Although illegal, hunting has increased in recent years and is driven by market demand. This challenges the widely held belief that waterbird hunting in India is a low intensity, subsistence activity, and undermines the importance of agricultural wetlands in waterbird conservation. © 2017 Royal Swedish Academy of Sciences

PubMed | National Center for Biological science, Agumbe Rainforest Research Station and Foundation for Ecological Research
Type: | Journal: Ambio | Year: 2017

Although Small Hydropower Projects (SHPs) are encouraged as sources of clean and green energy, there is a paucity of research examining their socio-ecological impacts. We assessed the perceived socio-ecological impacts of 4 SHPs within the Western Ghats in India by conducting semi-structured interviews with local respondents. Primary interview data were sequentially validated with secondary data, and respondent perceptions were subsequently compared against the expected baseline of assured impacts. We evaluated the level of awareness about SHPs, their perceived socio-economic impacts, influence on resource access and impacts on human-elephant interactions. The general level of awareness about SHPs was low, and assurances of local electricity and employment generation remained largely unfulfilled. Additionally most respondents faced numerous unanticipated adverse impacts. We found a strong relationship between SHP construction and increasing levels of human-elephant conflict. Based on the disparity between assured and actual social impacts, we suggest that policies regarding SHPs be suitably revised.

Vaidyanathan S.,Foundation for Ecological Research | Vaidyanathan S.,Wildlife Conservation Society | Krishnaswamy J.,Ashoka Trust for Research in Ecology and the Environment | Samba Kumar N.,Wildlife Conservation Society | And 3 more authors.
Biological Conservation | Year: 2010

Tropical forests are influenced by regional and global bio-climatic processes as well as local anthropogenic disturbances. Most studies have ignored the synergistic influence of bio-physical processes operating at large spatial scales and local human use on forest vegetation and fauna. Assessments of forest condition change using time-series of remotely sensed data need to be supported by measurements under the canopy. The Tadoba-Andhari Tiger Reserve (TATR) in India is a protected area that has a long history of human resource extraction and settlements. Like much of South Asia, it has undergone major shifts in rainfall in the last hundred years. We examine trends in forest greenness over two and half decades and assess spatial patterns in rates of change. We also analyze ground based measurements of human impacts on flora and fauna. Trends in forest canopy greenness show two distinct phases: a period of decline from 1980s to mid-90s, followed by a recovery. These trends are a function of initial greenness and are best explained by prevailing climatic regimes, feed-backs from human use, and park management practices and protection. Negative impacts to flora and fauna on the ground were, however, wide-spread during the recovery period and are influenced by proximity to nearest settlement as well as combined distance from all settlements. Remotely sensed data cannot effectively detect these processes under the canopy. There is an urgent need to incorporate monitoring of long-term bio-climatic processes and their interaction with short and long-term effects of human-use and disturbance arising from processes at local, regional and larger spatial scales around protected areas to effectively manage these reserves. © Elsevier Ltd.

Joshi A.,Tata Institute of Fundamental Research | Vaidyanathan S.,Foundation for Ecological Research | Mondo S.,Tata Institute of Fundamental Research | Edgaonkar A.,IndiaInstitute of Forest Management | Ramakrishnan U.,Tata Institute of Fundamental Research
PLoS ONE | Year: 2013

Today, most wild tigers live in small, isolated Protected Areas within human dominated landscapes in the Indian subcontinent. Future survival of tigers depends on increasing local population size, as well as maintaining connectivity between populations. While significant conservation effort has been invested in increasing tiger population size, few initiatives have focused on landscape-level connectivity and on understanding the effect different landscape elements have on maintaining connectivity. We combined individual-based genetic and landscape ecology approaches to address this issue in six protected areas with varying tiger densities and separation in the Central Indian tiger landscape. We non-invasively sampled 55 tigers from different protected areas within this landscape. Maximum-likelihood and Bayesian genetic assignment tests indicate long-range tiger dispersal (on the order of 650 km) between protected areas. Further geo-spatial analyses revealed that tiger connectivity was affected by landscape elements such as human settlements, road density and host-population tiger density, but not by distance between populations. Our results elucidate the importance of landscape and habitat viability outside and between protected areas and provide a quantitative approach to test functionality of tiger corridors. We suggest future management strategies aim to minimize urban expansion between protected areas to maximize tiger connectivity. Achieving this goal in the context of ongoing urbanization and need to sustain current economic growth exerts enormous pressure on the remaining tiger habitats and emerges as a big challenge to conserve wild tigers in the Indian subcontinent. © 2013 Joshi et al.

Srinivasaiah N.M.,Tata Institute of Fundamental Research | Anand V.D.,A Rocha India | Vaidyanathan S.,Foundation for Ecological Research | Sinha A.,Indian Institute of Science | Sinha A.,Nature Conservation Foundation
PLoS ONE | Year: 2012

Background: A dearth in understanding the behavior of Asian elephants (Elephas maximus) at the scale of populations and individuals has left important management issues, particularly related to human-elephant conflict (HEC), unresolved. Evaluation of differences in behavior and decision-making among individual elephants across groups in response to changing local ecological settings is essential to fill this gap in knowledge and to improve our approaches towards the management and conservation of elephants. Methodology/Principal Findings: We hypothesized certain behavioral decisions that would be made by Asian elephants as reflected in their residence time and movement rates, time-activity budgets, social interactions and group dynamics in response to resource availability and human disturbance in their habitat. This study is based on 200 h of behavioral observations on 60 individually identified elephants and a 184-km2 grid-based survey of their natural and anthropogenic habitats within and outside the Bannerghatta National Park, southern India during the dry season. At a general population level, the behavioral decisions appeared to be guided by the gender, age and group-type of the elephants. At the individual level, the observed variation could be explained only by the idiosyncratic behaviors of individuals and that of their associating conspecific individuals. Recursive partitioning classification trees for residence time of individual elephants indicated that the primary decisions were taken by individuals, independently of their above-mentioned biological and ecological attributes. Conclusions/Significance: Decision-making by Asian elephants thus appears to be determined at two levels, that of the population and, more importantly, the individual. Models based on decision-making by individual elephants have the potential to predict conflict in fragmented landscapes that, in turn, could aid in mitigating HEC. Thus, we must target individuals, in addition to populations, in our efforts to manage and conserve this threatened species, particularly in human-dominated landscapes. © 2012 Srinivasaiah et al.

Nayak R.R.,Wildlife Conservation Society | Nayak R.R.,Center for Wildlife Studies | Vaidyanathan S.,Foundation for Ecological Research | Krishnaswamy J.,Ashoka Trust for Research in Ecology and Environment
Agriculture, Ecosystems and Environment | Year: 2014

Tropical dry forests and savannas are important repositories of plant diversity and ecosystem services in the tropics. These ecosystems are also used extensively for grazing by livestock, and represent a critical element of the rural economy of many tropical countries. Fire is considered as a part of co-evolution in these ecosystems across the globe. However, in recent decades, there has been a shift in historical fire regime. Fire has become more frequent in these landscapes, and could be further enhanced under climate change. This poses threats to existing biodiversity, ecosystem processes, and rural economy. We asked how variability in fire frequency has influenced diversity and heterogeneity in grass species composition, and richness and abundance of grass species preferred by large herbivores (referred to as grazing acceptability) in a South Indian tropical savanna forest. We assumed that an increase in fire frequency acts as the active constraint and limits an ecosystem from attaining the maximum heterogeneity, and the maximum grazing acceptability (maximum richness and abundance of grass species preferred by herbivores) in its native settings. We used MODIS active fire and burned area products to estimate fire frequency across the landscape. A nested sampling approach was used to collect information on vegetation and soil at different fire frequencies. Quantile regression analyses indicated that diversity and heterogeneity in grass species composition as well as grazing acceptability decreased with increasing fire frequencies. We found that livestock grazing intervened with the observed vegetation patterns; grass species diversity and heterogeneity, and grazing acceptability increased with grazing intensity at lower quantiles. Other measured covariates, rainfall, and soil-fertility, alone were not able to explain the observed vegetation patterns in the landscape. The results show a need to control annual fires but allow and manage intermittent fires in this landscape. A complete suppression of fire is not desirable as fire releases nutrients from burning of deeper-rooted vegetation and thus acts as a periodic nutrient pump. It also played an important role in maintaining the grass cover by reducing shrub cover. Hence, it is important to consider the complex interactions between fires-grazers-soil-vegetation to develop effective management practices. We conclude that fire frequency should be managed at low to intermediate levels (one fire in every 5-9 years, resembling the native settings), and grazing regulated, in order to sustain wild and domestic herbivores, biodiversity, and other key ecosystem processes and services over the long-term. © 2014 Elsevier B.V.

Bhalla R.S.,Foundation for Ecological Research | Devi Prasad K.V.,Pondicherry University | Pelkey N.W.,Juniata College
Water Resources Research | Year: 2013

Watershed development (WSD) is an important and expensive rural development initiative in India. Proponents of the approach contend that treating watersheds will increase agricultural and overall biomass productivity, which in turn will reduce rural poverty. We used satellite-measured normalized differenced vegetation index as a proxy for land productivity to test this crucial contention. We compared microwatersheds that had received funding and completed watershed restoration with adjacent untreated microwatersheds in the same region. As the criteria used can influence results, we analyzed microwatersheds grouped by catchment, state, ecological region, and biogeographical zones for analysis. We also analyzed pre treatment and posttreatment changes for the same watersheds in those schemes. Our findings show that WSD has not resulted in a significant increase in productivity in treated microwatersheds at any grouping, when compared to adjacent untreated microwatershed or the same microwatershed prior to treatment. We conclude that the well-intentioned people-centric WSD efforts may be inhibited by failing to adequately address the basic geomorphology and hydraulic condition of the catchment areas at all scales. ©2013. American Geophysical Union. All Rights Reserved.

Bhalla R.S.,Foundation for Ecological Research | Pelkey N.W.,Juniata College | Prasad K.V.D.,Pondicherry University
Water Resources Management | Year: 2010

We analyse the suitability of Government of India's 2003 and 2008 common guidelines for prioritising micro-watersheds for restoration. These guidelines attempt to balance the need for improved hydraulic function with poverty alleviation and agricultural productivity. To do so, they provide a set of sub-criteria for prioritising micro-watersheds for treatment. We ranked the microwatersheds in the Kalivelli basin in South India based on these sub-criteria. We then compared the 2003 with the 2008 guidelines using GIS and spatial statistics. Visual inspection of the resulting digital maps and spatial autocorrelation analysis showed that individual sub-criteria within a guideline were highly positively auto correlated. Spatial cross-correlations using Mantels test between sub-criteria in the same guidelines produced negative results however. Very different watersheds would have been selected for treatment using the 2003 vs. the 2008 guidelines. While this could have been evidence that the 2008 guidelines were an improvement over the 2003 guidelines, comparing the planning outcomes did not support this conclusion. We conclude that criteria used to select micro-watersheds for hydrologic treatment should be re-formulated emphasizing efffcient resource use and improved hydraulic function prior to social and economic concerns. Finally, we argue that a combined GIS and spatial analysis approach is amenable to quickly evaluating watershed selection criteria as well as assessing post implementation outcomes. © 2010 Springer Science+Business Media B.V.

Gangadharan A.,Tamil University | Vaidyanathan S.,Foundation for Ecological Research | St. Clair C.C.,University of Alberta
Animal Conservation | Year: 2016

In biodiversity-rich landscapes that are developing rapidly, it is generally impossible to delineate land use and prioritize conservation actions in relation to the full variability of species and their responses to anthropogenic activity. Consequently, conservation policy often focuses on protecting habitat used by a few flagship, indicator or umbrella species like tigers Panthera tigris and Asian elephants Elephas maximus, which potentially leaves out species that do not share these habitat preferences. We demonstrate an empirical approach that clustered 14 mammals into surrogate groups that reflect their unique conservation needs. We surveyed a 787 km2 multiple-use area in the Shencottah Gap of the Western Ghats, India, using foot surveys and camera-trap surveys. Using ecological niche factor analysis, we generated indices of species prevalence (marginality and tolerance) and habitat preferences (factor correlations to marginality axis). We then clustered species by both of the above index types to reveal four clusters based on prevalence and four clusters based on habitat preference. Most clusters contained at least one threatened species. Low-prevalence lion-tailed macaques Macaca silenus and tigers were strongly associated with closed forests and low human disturbance. But elephants, sloth bears Melursus ursinus and gaur Bos gaurus were more tolerant of anthropogenic impact, and sloth bears and gaur preferred open forests and grasslands. Dhole Cuon alpinus and sambar Rusa unicolor were associated with highly anthropogenic habitat (farmland, cash crop and forestry plantations) with high human use. Thus, reliance on flagship species for conservation planning can both underestimate and overestimate the ability of other species to persist in multiple-use landscapes; protecting flagship species would only protect species with similar habitat preferences. For species that avoid human impacts more than the flagship species, core habitat must be protected from human disturbance. For more tolerant species, conservation in anthropogenic habitat may hinge on policies that bolster coexistence with humans. © 2016 The Zoological Society of London.

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