- Popular Article2014கோடியக்கரை: விருந்தாளிப் பறவைகளின் உல்லாச விடுதி. (On Point Calimere Wildlife Sanctuary)தி இந்து நாளிதழ். The Hindu Tamil News Daily. 22th July 2014.
Jeganathan, P. (2014). கோடியக்கரை: விருந்தாளிப் பறவைகளின் உல்லாச விடுதி - தி இந்து நாளிதழ் உயிர்மூச்சு இணைப்பில், ‘இயற்கையின்வாசலில்’தொடர் எண் – 3. 22th July 2014. Kodiyakkarai: Virunthalip paravaigalin ullasa viduthi – Iyarkayin Vaasalil ArticleSeries No.3 (On Point Calimere Wildlife Sanctuary). The Hindu Tamil News Daily. 22th July 2014.
- Popular Article2014நண்டு வரைந்த அழகுக் கோலங்கள். (On Soldier Crab and its sunburst)தி இந்து நாளிதழ். The Hindu Tamil News Daily. 14th October 2014.
Jeganathan, P. (2014). நண்டு வரைந்த அழகுக் கோலங்கள் - தி இந்து நாளிதழ் உயிர்மூச்சு இணைப்பில், ‘இயற்கையின் வாசலில்’ தொடர் எண் – 15. 14th October 2014. Nandu Varaintha Azagu Kolangal– Iyarkayin Vaasalil ArticleSeries No.15 (On Soldier Crab and its sunburst). The Hindu Tamil News Daily. 14th October 2014.
- Popular Article2014ஆமைகளைக் காப்பாற்றிய குட்டி நட்சத்திரங்கள். (On saving the star tortoises by kids)தி இந்து நாளிதழ். The Hindu Tamil News Daily.
Jeganathan, P. (2014). ஆமைகளைக் காப்பாற்றிய குட்டி நட்சத்திரங்கள் - தி இந்து நாளிதழ் உயிர்மூச்சு இணைப்பில், ‘இயற்கையின் வாசலில்’ தொடர் எண் – 17. 28th October 2014. Amaigalai Kappatriya Kutti Natchathirangal– Iyarkayin Vaasalil ArticleSeries No.17 (On saving the star tortoises by kids). The Hindu Tamil News Daily. 28th October 2014.
- Popular Article2014அற்புதங்களுக்குப் பின் ஒளிந்திருக்கும் ‘செட்டப்'. (On irresponsible and unethical nature photography)தி இந்து நாளிதழ். The Hindu Tamil News Daily. 11th November 2014.
Jeganathan, P. (2014).அற்புதங்களுக்குப் பின் ஒளிந்திருக்கும் ‘செட்டப்' - தி இந்து நாளிதழ் உயிர்மூச்சு இணைப்பில், ‘இயற்கையின் வாசலில்’ தொடர் எண் – 19. 11th November 2014. Arputhangaluku pin olinthirukum setup– Iyarkayin Vaasalil ArticleSeries No.19 (On irresponsible and unethical nature photography). The Hindu Tamil News Daily. 11th November 2014.
- Popular Article2014நீங்களும் விஞ்ஞானிதான்! (On Citizen Science)தி இந்து நாளிதழ். The Hindu Tamil News Daily. 18th November 2014.
Jeganathan, P. (2014).நீங்களும் விஞ்ஞானிதான்! - தி இந்து நாளிதழ் உயிர்மூச்சு இணைப்பில், ‘இயற்கையின் வாசலில்’ தொடர் எண் – 20. 18th November 2014. Neengalum vingnanithan– Iyarkayin Vaasalil ArticleSeries No.20 (On Citizen Science). The Hindu Tamil News Daily. 18th November 2014.
- Popular Article2014கள்ளச் சந்தைக்குப் பலியாகும் சேட்டைக்காரர்கள். (On Otters of India and their threats)தி இந்து நாளிதழ். The Hindu Tamil News Daily. 4th November 2014.
Jeganathan, P. (2014).கள்ளச் சந்தைக்குப் பலியாகும் சேட்டைக்காரர்கள் - தி இந்து நாளிதழ் உயிர்மூச்சு இணைப்பில், ‘இயற்கையின் வாசலில்’தொடர் எண் – 18. 4th November 2014. Kalla Santhaiku Paliyagum Settaikarargal– Iyarkayin Vaasalil ArticleSeries No.18 (On Otters of India and their threats). The Hindu Tamil News Daily. 4th November 2014.
- Popular Article2014மக்கள் விஞ்ஞானிகளே, வாருங்கள்! (On various citizen science project initiatives in India)25th November 2014.
Jeganathan, P. (2014). மக்கள் விஞ்ஞானிகளே, வாருங்கள்! - தி இந்து நாளிதழ் உயிர்மூச்சு இணைப்பில், ‘இயற்கையின் வாசலில்’ தொடர் எண் – 21. 25th November 2014. Makkal Vingnanigale Varungal!– Iyarkayin Vaasalil ArticleSeries No.21 (On various citizen science project initiatives in India). The Hindu Tamil News Daily. 25th November 2014.
- Popular Article2014தமிழகத்தின் சூழல் தொகுப்புகளும் வாழிடங்களும். (Ecosystems and Habitats of Tamil Nadu)மலையாள மனோரமா இயர்புக் தமிழ் – 2015. Manorama Year Book Tamil - 2015. December 2014. Pp. 178-195.
Jeganathan, P. (2014). தமிழகத்தின் சூழல் தொகுப்புகளும் வாழிடங்களும் - மலையாள மனோரமா இயர்புக் தமிழ் – 2015. December 2014. பக்கங்கள்-178-195.Thamilagathil Soozal Thoguppugalum, Vazidangalum (Ecosystems and Habitats of Tamil Nadu). Manorama Year Book Tamil - 2015. Malayala Manorama Press, Kottayam – 686 001. December 2014. Pp. 178-195.
- Report2014Ecology and conservation status of leopards in Bhadravathi Territorial DivisionOctober 2014Download
PDF, 15.6 MB
Despite the leopard (Panthera pardus) being a highly conflict-prone species with a wide distribution range, there are few population estimates of this species in Karnataka, especially outside protected areas. Effective conservation of this large carnivore and mitigation measures towards leopard conflict requires reliable estimates of population density in various habitats and landscapes with different management priorities. We conducted a population estimation exercise for the leopard using photographic capture-recapture analysis, using spatially explicit capture–recapture (SECR) models, in the multiple-use forests in Bhadravathi Division in central-interior Karnataka. Density estimates for leopards in this 370 km2 area, which includes 14 state, minor forests and sandal reserves, all continuous to each other, was found to be 11.1/100 km2 (95% CI 9.7-12.2/100 km2) with an estimated population size of 44 individuals (95% CI 39-49). We also recorded 14 species of large and small leopard prey from this area including gaur, sambar, chital, barking deer, four-horned antelope, wild pig and mouse deer. Using publicly available forest cover analyses tools, we estimate that the area has lost forest cover of ~14% since their notification between 1905 and 1941. We propose that the forest areas surveyed be declared as a wildlife sanctuary under the Wildlife Protection Act 1972 to uphold to their rich wildlife values.
- Popular Article2014உண்டி கொடுத்தோம், உயிர் கொடுத்தோமா? (On ill effects of feeding monkeys).தி இந்து நாளிதழ். The Hindu Tamil News Daily. 16th September 2014.
Jeganathan, P. (2014).உண்டி கொடுத்தோம், உயிர் கொடுத்தோமா? - தி இந்து நாளிதழ் உயிர்மூச்சு இணைப்பில், ‘இயற்கையின் வாசலில்’ தொடர்எண் – 11. 16th September 2014. Undi Koduthom Uyir Koduthoma?– Iyarkayin Vaasalil ArticleSeries No.11 (On ill effects of feeding monkeys). The Hindu Tamil News Daily. 16th September 2014.
- Popular Article2014ஓர் இன்பச் சுற்றுலாவும், அதற்குப் பிறகும். (On impact of mass tourism in hill stations and irresponsible tourists)தி இந்து நாளிதழ். The Hindu Tamil News Daily. 23rd September 2014.
Jeganathan, P. (2014). ஓர் இன்பச் சுற்றுலாவும், அதற்குப் பிறகும் - தி இந்து நாளிதழ் உயிர்மூச்சு இணைப்பில், ‘இயற்கையின் வாசலில்’ தொடர்எண் – 12. 23rd September 2014. Or Inba Sutrulavum Atharku Piragum– Iyarkayin Vaasalil ArticleSeries No.12 (On impact of mass tourism in hill stations and irresponsible tourists). The Hindu Tamil News Daily. 23rd September 2014.
- Journal Article2014The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impactsEcology and Evolution, Volume 4, Issue 24 Pages: 4701–4735
Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world.
- Popular Article2013Waiting for the orioleThe Hindu in School, 24 April
- Popular Article2013Ptero’s story as told by a Jack treeThe Hindu in School, 20 March
- Journal Article2013Greener pastures? High-density feeding aggregations of green turtles precipitate species shifts in seagrass meadowsJournal of Ecology. 101: 1158-1168
1. Historical declines of marine megaherbivores have led to a view of seagrass communities structured largely by abiotic disturbance and plant competition. There is, however, growing recognition of the significance of top-down control through herbivory, on seagrass ecosystem processes, raising the question of how meadows functioned under historically high populations of megaherbivores. 2. We assess the impacts of such intense herbivory on seagrass meadow composition in the Lakshadweep islands (India), where high-density feeding aggregations of green turtles have persisted for over a decade. We use a series of complementary approaches: (i) natural herbivory exclosures (ii) published data on seagrass composition before and after turtles established (at one atoll: Agatti) and (iii) present species composition along a turtle herbivory gradient over multiple atolls.
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- Journal Article2013Antelope mating strategies facilitate invasion of grasslands by a woody weed.Oikos. 122(10): 1441-1452.Download
PDF, 357 KB
Intra and interspecific variation in frugivore behaviour can have important consequences for seed dispersal outcomes. However, most information comes from among-species comparisons, and within-species variation is relatively poorly understood. We examined how large intraspecific differences in the behaviour of a native disperser, blackbuck antelope Antilope cervicapra, influence dispersal of a woody invasive, Prosopis juliflora, in a grassland ecosystem. Blackbuck disperse P. juliflora seeds through their dung. In lekking blackbuck populations, males defend clustered or dispersed mating territories. Territorial male movement is restricted, and within their territories males defecate on dung-piles. In contrast, mixed-sex herds range over large areas and do not create dung-piles. We expected territorial males to shape seed dispersal patterns, and seed deposition and seedling recruitment to be spatially localized. Territorial males had a disproportionately large influence on seed dispersal. Adult males removed twice as much fruit as females, and seed arrival was disproportionately high on territories. Also, because lek-territories are clustered, seed arrival was spatially highly concentrated. Seedling recruitment was also substantially higher on territories compared with random sites, indicating that the local concentration of seeds created by territorial males continued into high local recruitment of seedlings. Territorial male behaviour may, thus, result in a distinct spatial pattern of invasion of grasslands by the woody P. juliflora. An ex situ experiment showed no beneficial effect of dung and a negative effect of light on seed germination. We conclude that large intraspecific behavioural differences within frugivore populations can result in significant variation in their effectiveness as seed dispersers. Mating strategies in a disperser could shape seed dispersal, seedling recruitment and potentially plant distribution patterns. These mating strategies may aid in the spread of invasives, such as P. juliflora, which could, in turn, negatively influence the behaviour and ecology of native dispersers.
- Journal Article2013Green turtle herbivory dominates the fate of seagrass primary production in the Lakshadweep islands (Indian Ocean)Marine Ecology Progress Series. 485:235-243
Historical global declines of megaherbivores from marine ecosystems have hitherto contributed to an understanding of seagrass meadow production dominated by detrital path- ways — a paradigm increasingly being questioned by recent re-evaluations of the importance of herbivory. Recoveries in green turtle populations at some locations provide an ideal opportunity to examine effects of high megaherbivore densities on the fate of seagrass production. We conducted direct field measurements of aboveground herbivory and shoot elongation rates in 9 seagrass meadows across 3 atolls in the Lakshadweep Archipelago (India) representing a gradient of green turtle densities. Across all meadows, green turtles consumed an average of 60% of the total leaf growth. As expected, herbivory rates were positively related to turtle density and ranged from being almost absent in meadows with few turtles, to potentially overgrazed meadows (ca. 170% of leaf growth) where turtles were abundant. Turtle herbivory also substantially reduced shoot elongation rates. Simulated grazing through clipping experiments confirmed this trend: growth rates rapidly declined to almost half in clipped plots relative to control plots. At green turtle den- sities similar to historical estimates, herbivory not only dominated the fate of seagrass primary pro- duction but also drastically reduced production rates in grazed meadows. Intensive turtle grazing and associated movement could also modify rates of detrital cycling, leaf export and local carbon burial, with important consequences for the entire seascape.
- Dataset2013Data from: Influence of gaze and directness of approach on the escape responses of the Indian rock lizard, Psammophilus dorsalis (Gray, 1831).Dryad Digital Repository. doi:10.5061/dryad.1h551
Contains both raw data and analysis scripts. Permanent link to the dataset and scripts on Dryad:
- Book Chapter2013Anthropogenic Influences on Macaque Populations and Their Genetic ConsequencesPages 209 to 224 in S. Radhakrisna and A. Sinha (editors) The Macaque Connection: Cooperation and Conflict between Humans and Macaques, Springer, New Delhi.Download
PDF, 338 KB
Human–macaque interactions constitute a complex phenomenon influencing perhaps the biology of the macaque more profoundly than ours. At the population level, humans tend to influence the distribution, demography, immunology and even behaviour of the macaque species they interact with though none of these interactions are ever simple. These works at different levels, interacting, in turn, with other environmental factors and most of these impacts are likely to have genetic consequences over the long term. In this chapter, we reviewed available literature on anthropogenic impacts on macaque populations. We should, however, stress that our current state of knowledge, unfortunately, suffers from a serious lack of insight into such genetic impacts. There is, therefore, a dire need for long-term genetic monitoring programmes to understand the effect of anthropogenic factors on the dispersal and demography of different macaque species.
- Book2013The Macaque Connection: Cooperation and Conflict between Humans and MacaquesSeries: Developments in Primatology: Progress and Prospects, Vol. 43, Springer, New Delhi
Most successful among the non-human primates in terms of geographical distribution and adaptability to ecological habitats, macaques have existed for many thousands of years in close contact with modern humans, the only primate more successful than them. Centuries-old literary works attest to the fact that macaques have always been an intrinsic part of human lives and imaginations. In their interactions with humans, macaques play multiple roles that often transcend the boundaries of categorization. They are often, simultaneously, wildlife and domestic pets, sentient beings and experimental subjects, crop-raiding pests and religious symbols. In many parts of the tropics, macaques are an economic resource for human communities, as they provide meat and money through tourism and the animal trade. Equally, they cause much damage and bring about great economic losses due to their crop- and house-raiding tendencies. A more recent cause for alarm has been the possibility of transmission of diseases to humans due to contact with macaques. Across Asia, macaques, perhaps more than any other animal species, exemplify the multiple facets of synurbization and the conservation problems of commensal species. Humans and macaques associate in rather remarkable ways, and this volume explores the tone and nature of those human-macaque connections by focusing on various forms of interactions between macaques and humans, change in human attitudes vis-à-vis macaques over the ages, cultural views on macaques, human-macaque conflict and its conservation implications. Its holistic perspective of the myriad aspects that illustrate the singular relationship between men and macaques makes it essential reading not only for primatologists and anthropologists but also for anyone interested in the intricacies of human-animal relations.