- Book Chapter2015SciuridsIn: Mammals of South Asia: Volume 2, (eds A. J. T. Johnsingh & N. Manjrekar), pp. 513-573. Universities Press, Hyderabad.
- Journal Article2015Seed dispersal by avian frugivores: non-random heterogeneity at fine scales.Biotropica 47(1): 77-84.Download
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Seed dispersal studies have primarily examined dispersal as a function of distance from the parent tree and/or heterogeneity in dispersal due to animal use of nesting, roosting and sleeping sites. However, non-random heterogeneity in seed dispersal is also likely to result from the post-foraging behavior and movement of frugivores which prefer certain trees. To characterize variation in seed rain at fine scales, we studied the dispersal curve of Prunus ceylanica, a primarily bird-dispersed species. We compared seed rain at conspecifics, heterospecific fruiting trees with similar frugivore assemblages, emergent trees, and the landscape surrounding these trees. Seed rain of P. ceylanica was found to peak globally under the canopy of conspecifics but to peak locally under the canopy and immediate neighborhood of heterospecific fruiting trees. Our results demonstrate that seed rain is highly clumped even at fine spatial scales. A large proportion of seeds are dispersed in specific, localized regions. This variation can have important implications for plant population dynamics and might significantly alter the impact of post-dispersal processes. Seed dispersal models may need to incorporate this heterogeneity to explain manifestations of spatially explicit dynamics like mixed species ‘orchards’.
- Popular Article2015Message in a pollenThe Hindu in School, 1 April
- Popular Article2015Nono: king of the mountainsThe Hindu in School, 18 March
- Popular Article2015Hornbill hills: the hunterThe Hindu in School, 25 Feb
- Popular Article2015Hornbill hills: the protectorThe Hindu in School, 4 March
- Popular Article2015Balcony birdingThe Hindu in School, 4 Feb
- Popular Article2015Smelly StorkThe Hindu in School, 15 April
- Popular Article2015A crown in the flowerThe Hindu in School, 28 April
- Journal Article2015Reduced hornbill abundance associated with low seed arrival and altered recruitment in a hunted and logged tropical forestPLOSOne; DOI: 10.1371/journal.pone.0120062
Logging and hunting are two key direct threats to the survival of wildlife in the tropics, and also disrupt important ecosystem processes. We investigated the impacts of these two factors on the different stages of the seed dispersal cycle, including abundance of plants and their dispersers and dispersal of seeds and recruitment, in a tropical forest in north-east India. We focused on hornbills, which are important seed dispersers in these forests, and their food tree species. We compared abundances of hornbill food tree species in a site with high logging and hunting pressures (heavily disturbed) with a site that had no logging and relatively low levels of hunting (less disturbed) to understand logging impacts on hornbill food tree abundance. We compared hornbill abundances across these two sites. We, then, compared the scatter-dispersed seed arrival of five large-seeded tree species and the recruitment of four of those species. Abundances of hornbill food trees that are preferentially targeted by logging were two times higher in the less disturbed site as compared to the heavily disturbed site while that of hornbills was 22 times higher. The arrival of scatter-dispersed seeds was seven times higher in the less disturbed site. Abundances of recruits of two tree species were significantly higher in the less disturbed site. For another species, abundances of younger recruits were significantly lower while that of older recruits were higher in the heavily disturbed site. Our findings suggest that logging reduces food plant abundance for an important frugivore-seed disperser group, while hunting diminishes disperser abundances, with an associated reduction in seed arrival and altered recruitment of animal-dispersed tree species in the disturbed site. Based on our results, we present a conceptual model depicting the relationships and pathways between vertebrate-dispersed trees, their dispersers, and the impacts of hunting and logging on these pathways.
- Journal Article2015Diet and foraging behaviour of Purple Cochoa Cochoa purpurea in Namdapha National Park, IndiaForktail, 30, 145-147
- Journal Article2015Status of the mountain ungulate prey of the Endangered snow leopard Panthera uncia in the Tost Local Protected Area, South Gobi, MongoliaOryx, doi:10.1017/S0030605314001203
- Popular Article2015Life of fryThe Hindu in School, 3 June
- Popular Article2015Survival tips to a young fish from an old fishThe Hindu in School, 10 June
- Popular Article2015How I wish I was a fish!The Hindu in School, 1 July
- Book Chapter2015Finding the middle road: Grounded approaches to mitigate highway impacts in tiger reservesHandbook of Road Ecology, Editors : Rodney van der Ree, Daniel J. Smith and Clara Grilo. Publishers : John Wiley & Sons, Ltd.
- Report2015Hornbill Watch Report June 2014 to May 2015May 2015, www.hornbills.inDownload
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An update that summarises the information obtained on Indian hornbills contributed by people on the Hornbill Watch website for one year (June 2014 to May 2015).
- Journal Article2015Perceptions of priority issues in the conservation of biodiversity and ecosystems in IndiaBiological Conservation, 187: 201-211Download
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We report on the results of a country-wide survey of people’s perceptions of issues relating to the con- servation of biodiversity and ecosystems in India. Our survey, mainly conducted online, yielded 572 respondents, mostly among educated, urban and sub-urban citizens interested in ecological and environ- mental issues. 3160 ‘‘raw’’ questions generated by the survey were iteratively processed by a group of ecologists, environmental and conservation scientists to produce the primary result of this study: a sum- marized list of 152 priority questions for the conservation of India’s biodiversity and ecosystems, which range across 17 broad thematic classes. Of these, three thematic classes—‘‘Policy and Governance’’, ‘‘Biodiversity and Endangered Species’’ and ‘‘Protection and Conservation’’—accounted for the largest number of questions. A comparative analysis of the results of this study with those from similar studies in other regions brought out interesting regional differences in the thematic classes of questions that were emphasized and suggest that local context plays a large role in determining emergent themes. We believe that the ready list of priority issues generated by this study can be a useful guiding framework for conservation practitioners, researchers, citizens, policy makers and funders to focus their resources and efforts in India’s conservation research, action and funding landscape.
- Popular Article2015Eyes in the forestThe Hindu in School, 22 July
- Journal Article2015Invasive alien species in relation to edges and forest structure in tropical rainforest fragments of the Western GhatsTropical Ecology 56: 233-244Download
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The impact of invasive alien species on native ecosystems is a major conservation issue in the tropics. This study in the rainforest fragments of Anamalai hills, in the Western Ghats biodiversity hotspot, assessed the effects of distance from edges and forest structure on the occurrence and abundance of three invasive alien species (Chromolaena odorata, Lantana camara, and Maesopsis eminii). Replicate line transects were laid from the edges into the interiors of four fragments varying in disturbance level and area (32 ha – 200 ha). Densities of alien species in the protected site were lower than in the three disturbed fragments. Maesopsis eminii occurred at highest density (382 trees/ha) in the highly disturbed site where it also showed prolific regeneration (1510 saplings/ha). The invasive alien species showed no clear edge-to-interior pattern, instead their abundance appeared to be localized and related in a site-specific manner to disturbances such as presence of Eucalyptus plantation, canopy openings, and trails.