- 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’.
- Journal Article2015Changes in the institution of family among the ChangpasLadakh Studies 32 • January 2015 • 4 - 17Download
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This paper focuses on the Changpas of Kargyam, with a specific focus on rules, norms, and patterns that govern the construction of social relationships in the family system and the factors that have influenced it. It provides an overview and description of these changes based on fieldwork carried out in 2010-12. Some of the important factors are the increased presence of Indian security forces after the 1962 Indo-China war, tourism, a new motor road, educational facilities and various government welfare schemes. Each of these factors has had an impact on the social structure of Changpa communities
- Journal Article2014Long-lived benthic predators require structurally stable reefs in the face of repeated climate-change disturbancesCoral Reefs. 33: 289-302
Benthic recovery from climate-related disturbances does not always warrant a commensurate functional recovery for reef-associated fish communities. Here, we examine the distribution of benthic groupers (family Serranidae) in coral reef communities from the Lakshadweep archipelago (Arabian Sea) in response to structural complexity and long-term habitat stability. These coral reefs that have been subject to two major El Nin ̃o Southern Oscillation-related coral bleaching events in the last decades (1998 and 2010). First, we employ a long-term (12-yr) benthic- monitoring dataset to track habitat structural stability at twelve reef sites in the archipelago. Structural stability of reefs was strongly driven by exposure to monsoon storms and depth, which made deeper and more sheltered reefs on the eastern aspect more stable than the more exposed (western) and shallower reefs. We surveyed groupers (species richness, abundance, biomass) in 60 sites across the entire archipelago, representing both exposures and depths. Sites were selected along a gradient of structural complexity from very low to high. Grouper biomass appeared to vary with habitat stability with significant differences between depth and exposure; sheltered deep reefs had a higher grouper biomass than either sheltered shallow or exposed (deep and shallow) reefs. Species richness and abundance showed similar (though not significant) trends. More interestingly, average grouper biomass increased exponentially with structural complexity, but only at the sheltered deep (high stability) sites, despite the availability of recovered structure at exposed deep and shallow sites (lower-stability sites). This trend was especially pronounced for long-lived groupers (life span [10 yrs). These results suggest that long-lived groupers may prefer temporally stable reefs, independent of the local availability of habitat structure. In reefs subject to repeated disturbances, the presence of structurally stable reefs may be critical as refuges for functionally important, long-lived species like groupers.
- Journal Article2014Roads emerging as a critical threat to leopards in India?Cat News 60 Spring 2014 (30)
Leopards (Panthera pardus) face severe threat from poaching, loss of habitat and killing in retaliation to conflict. However, in India a new threat appears to be emerging in the form of vehicle accident mortalities. In the past 60 months 23 leopards have been recorded as killed due to road accidents in the southern Indian state of Karnataka alone. When roads overlap with important wildlife habitats, considerable scrutiny and critical conservation planning is urgently required
- Journal Article2014Bats in Indian coffee plantations: doing more good than harm?Current Science 107: 1958-1960.Download
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Many bat species occur in Indian coffee plantations and despite sporadic reports of damage to commercial coffee crops, the literature shows little evidence for these claims. Measures that have been proposed to ‘control’ fruit bats are likely to be ineffective and even counter-productive. Instead, insect-eating bats should be encouraged by planters as they help control herbivorous and disease-carrying insects, while fruit bats pollinate flowers and disperse seeds of many useful plants and shade tree species. More research is needed to quantify any crop damage caused by bats and to look for sustainable solutions where necessary.
PDF also available here: http://www.currentscience.ac.in/Volumes/107/12/1958.pdf
- Journal Article2014The response of birds and mixed-species bird flocks to human-modified landscapes in Sri Lanka and southern IndiaForest Ecology and Management 329: 384–392Download
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While there is no substitute for undisturbed forest, secondary forests and agroforests are increasingly common in tropical areas and may be critical to conservation plans. We compared the diversity and abundance of birds and the characteristics of mixed-species bird flocks in forests inside protected reserves to ‘‘buffer’’ areas, consisting of degraded forests and non-native timber plantations at reserve boundaries, and to agricultural areas. We monitored a network of 57 transects placed over an altitudinal gradient (90–2180 masl) in Sri Lanka and southern India, collecting 398 complete flock observations and 35,686 observations of birds inside and outside of flocks over two years. Flocks were rarely found in agri- cultural areas. However, the density of flocks in buffer areas was similar to that in forests, although buffer flocks were smaller in average flock size and differed significantly in composition, as measured by the proportion of species that were classified, from the literature, as forest interior or open-landscape species. While flock composition was distinct between agricultural, buffer and forest areas, the differences in the composition of flocks was not as great as the differences between the overall communities in these different habitats. Considering buffer transects alone, pine plantations retained fewer forest interior species in flocks than did forests, and small areas of agriculture and abandoned agriculture attracted open-landscape species. Though clearly not equivalent to protected forests, degraded forests and agroforests in buffer areas still hold some conservation value, with forest species found particularly in mixed-species flocks in these human-modified habitats.
- Journal Article2014Acoustic identification of bats in the southern Western Ghats, IndiaActa Chiropterologica 16: 213–222Download
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Bats play crucial roles in ecosystems, are increasingly used as bio-indicators and are an important component of tropical diversity. Ecological studies and conservation-oriented monitoring of bats in the tropics benefit from published libraries of echolocation calls, which are not readily available for many tropical ecosystems. Here, we present the echolocation calls of 15 species from the Valparai plateau in the Anamalai Hills, southern Western Ghats of India: three rhinolophids (Rhinolophus beddomei, R. rouxii (indorouxii), R. lepidus), one hipposiderid (Hipposideros pomona), nine vespertilionids (Barbastella leucomelas darjelingensis, Hesperoptenus tickelli, Miniopterus fuliginosus, M. pusillus, Myotis horsfieldii, M. montivagus, Pipistrellus ceylonicus, Scotophilus heathii, S. kuhlii), one pteropodid (Rousettus leschenaultii) and one megadermatid (Megaderma spasma). Discriminant function analyses using leave-one-out cross validation classified bats producing calls with a strong constant frequency (CF) component with 100% success and bats producing frequency modulated (FM) calls with 90% success. For five species, we report their echolocation calls for the first time, and we present call frequencies for some species that differ from those published from other parts of the species’ ranges. This exemplifies the need for more local call libraries from tropical regions to be collected and published in order to record endemic species and accurately identify species whose calls vary biogeographically.
PDF also available here: http://dx.doi.org/10.3161/150811014X683408
- Journal Article2014Photographic records of the Ratel Mellivora capensis from the southern Indian state of KarnatakaSmall Carnivore Conservation, 50, 42-44.
Understanding about the occurrence and distribution of the Ratel Mellivora capensis from the Indian subcontinent is hindered by the animal’s elusive nature. The first photographic evidence of Ratel for the southern Indian state of Karnataka comprises 41 camera-trap records from Cauvery Wildlife Sanctuary. During January–March 2014, Ratels were detected in the sanctuary’s different forest types broadly in proportion to camera-trapping effort therein. A wider occupancy survey, using a range of methods including camera-trapping, would help obtain a better understanding of the distribution of this cryptic species in Karnataka and neighbouring regions.
- Journal Article2014A case of colour aberration in Stripe-necked Mongoose Herpestes vitticollis in the Western Ghats, IndiaSmall Carnivore Conservation 50: 76-77.
- Journal Article2014An elephantine challenge: human–elephant conflict distribution in the largest Asian elephant population, southern IndiaBiodiversity Conservation DOI 10.1007/s10531-014-0621-xDownload
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Wildlife conservation is a complex issue especially when it involves large carnivores or mega-herbivores that are conflict-prone. Karnataka state in southern India is known to harbor high density of wild elephants. This conservation success story also has opportunity costs for communities living in close proximity to elephants. Despite the fact that human–elephant conflict is a serious conservation and social issue, there is little quantitative understanding of conflict especially over large areas. Here we conduct the first analysis of human–elephant conflict distribution, severity and explanatory factors over the entire state of Karnataka. We use data from the state forest department records on villages that experience conflict, compensation payments made by the government, elephant den- sities, forest cover and perimeter, and presence of physical barriers to mitigate elephant conflict. In total, 60,939 incidences of crop loss were reported and US$ 2.99 m paid in compensation during April 2008–March 2011. A total of 91 people were killed by ele- phants and 101 elephants died in retaliatory killings during the study period. A total of 9.4 % of the state’s geographic area covering 25 of the 42 forest administrative divisions were affected. There was no significant difference in conflict incidences or compensation given between protected areas and non-protected areas. There was no correlation between conflict incidences/unit area and elephant density, forest cover, forest perimeter of pro- tected areas and presence of physical barriers. The results depict the importance of efficient management of physical barriers, conserving key habitat linkages, and acts as baseline data for future work.
- Journal Article2014Vigorous Dynamics Underlie a Stable Population of the Endangered Snow Leopard Panthera uncia in Tost Mountains, South Gobi, MongoliaPLoS One. DOI: 10.1371/journal.pone.0101319
- Journal Article2014The cashmere connection, biodiversity, and climate: response to Von Wehrden, et al
- Journal Article2014Tiger poaching and trafficking in India: estimating rates of occurrence and detection over four decadesBiological Conservation, doi: 10.1016/j.biocon.2014.08.016
Poaching, prey depletion and habitat destruction have decimated the world’s wild tiger population to fewer than 3200–4000. Despite focused efforts, poaching continues to be the key threat to tiger populations in India, home to more than half of the world’s tigers. A rise in the number of incidences of tiger poaching and trafficking may not essentially represent an increase in the actual occurrence of tiger poaching and trafficking, but can instead be an indication of better enforcement. With ad hoc detection rates, it becomes difficult to estimate the true quantum of poaching and the efficiency of enforcement. We empirically estimate the probability of occurrence of tiger crime and that of detecting it during periods of 3–7 years in the past 40 years in the 605 districts of India. We test the hypotheses that tiger crime is influenced by the presence of tiger trade hubs, proximity to a number of tiger habitats, and that tiger poachers prefer to use rail routes over road highways. The annual probability of detecting tiger crime was estimated to be highest (0.46, 95% CI = 0.38–0.54) in the period between 1993 and 1995. Our results identify 73 districts as current tiger crime hotspots with high (>0.5) probability of occurrence of tiger crime. We propose that the probability of occurrence of tiger crime can be a more reliable estimator of changing poaching pressures and that probability of detecting tiger crime provides a robust estimate of the efficiency in tackling tiger poaching and trafficking.
- Journal Article2014Vigorous dynamics underlie a stable population of the endangered snow leopard Panthera uncia in Tost Mountains, South Gobi, MongoliaPLoS ONE 9(7): e101319. DOI:10.1371/journal.pone.0101319
- Journal Article2014Occurrence of Small-toothed Palm Civet Arctogalidia trivirgata in Dampa Tiger Reserve, Mizoram, North-east IndiaSmall Carnivore Conservation 50: 47-49.Download
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Single Small-toothed Palm Civets Arctogalidia trivirgata were seen and photographed on two consecutive nights in March 2014 in Dampa Tiger Reserve, Mizoram, India. They visited a fruiting tree used also by Masked Palm Civet Paguma larvata and Common Palm Civet Paradoxurus hermaphroditus. The present note describes the observation, adding to the few recent records of A. trivirgata from North-east India. The sighting was close to the location of a 1995 sighting of Stripe-backed Weasel Mustela strigidorsa, another species rarely recorded in the region. We suggest further targeted spotlighting and camera-trap surveys for better documentation of the occurrence and distribution of small carnivores in Dampa.
- Journal Article2014Genetic diversity and population structure of Lantana camara in India indicates multiple introductions and gene flow.Plant Biology. 16(3): 651-658.Download
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Lantana camara is a highly invasive plant, which has spread over 60 countries and island groups of Asia, Africa and Australia. In India, it was introduced in the early nineteenth century, since when it has expanded and gradually established itself in almost every available ecosystem. We investigated the genetic diversity and population structure of this plant in India in order to understand its introduction, subsequent range expansion and gene flow. A total of 179 individuals were sequenced at three chloroplast loci and 218 individuals were genotyped for six nuclear microsatellites. Both chloroplasts (nine haplotypes) and microsatellites (83 alleles) showed high genetic diversity. Besides, each type of marker confirmed the presence of private polymorphism. We uncovered low to medium population structure in both markers, and found a faint signal of isolation by distance with microsatellites. Bayesian clustering analyses revealed multiple divergent genetic clusters. Taken together, these findings (i.e. high genetic diversity with private alleles and multiple genetic clusters) suggest that Lantana was introduced multiple times and gradually underwent spatial expansion with recurrent gene flow.
- Journal Article2014Multi-scale factors influencing human attitudes towards snow leopards and wolves.Conservation Biology DOI: 10.1111/cobi.12320
- Journal Article2014Tracing the geographic origin of traded leopardbody parts in the Indian subcontinent withDNA-based assignment testsConservation Biology, 2014, DOI: 10.1111/cobi.12393Download
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Illicit trade in wildlife products is rapidly decimating many species across the globe. Such trade is often underestimated for wide-ranging species until it is too late for the survival of their remaining populations. Policing this trade could be vastly improved if one could reliably determine geographic origins of illegal wildlife products and identify areas where greater enforcement is needed. Using DNA-based assignment tests (i.e., samples are assigned to geographic locations), we addressed these factors for leopards (Panthera pardus) on the Indian subcontinent. We created geography-specific allele frequencies from a genetic reference database of 173 leopards across India to infer geographic origins of DNA samples from 40 seized leopard skins. Sensitivity analyses of samples of known geographic origins and assignments of seized skins demonstrated robust assignments for Indian leopards. We found that confiscated pelts seized in small numbers were not necessarily from local leopards. The geographic footprint of large seizures appeared to be bigger than the cumulative footprint of several smaller seizures, indicating widespread leopard poaching across the subcontinent. Our seized samples had male-biased sex ratios, especially the large seizures. From multiple seized sample assignments, we identified central India as a poaching hotspot for leopards. The techniques we applied can be used to identify origins of seized illegal wildlife products and trade routes at the subcontinent scale and beyond.
- 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.
- Journal Article2014Assessing leopard occurrence in the plantation landscape of Valparai, Anamalai HillsCurrent Science 107: 1381-1385.Download
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Available from this link: http://www.currentscience.ac.in/Volumes/107/09/1381.pdf