- Journal Article2012To eat and not be eaten: modelling resources and safety in multi-species animal groups.PLoS ONE. 7(7): e42071.Download
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Using mixed-species bird flocks as an example, we model the payoffs for two types of species from participating in multi-species animal groups. Salliers feed on mobile prey, are good sentinels and do not affect prey capture rates of gleaners; gleaners feed on prey on substrates and can enhance the prey capture rate of salliers by flushing prey, but are poor sentinels. These functional types are known from various animal taxa that form multi-species associations. We model costs and benefits of joining groups for a wide range of group compositions under varying abundances of two types of prey–prey on substrates and mobile prey. Our model predicts that gleaners and salliers show a conflict of interest in multi-species groups, because gleaners benefit from increasing numbers of salliers in the group, whereas salliers benefit from increasing gleaner numbers. The model also predicts that the limits to size and variability in composition of multi-species groups are driven by the relative abundance of different types of prey, independent of predation pressure. Our model emphasises resources as a primary driver of temporal and spatial group dynamics, rather than reproductive activity or predation per se, which have hitherto been thought to explain patterns of multi-species group formation and cohesion. The qualitative predictions of the model are supported by empirical patterns from both terrestrial and marine multi-species groups, suggesting that similar mechanisms might underlie group dynamics in a range of taxa. The model also makes novel predictions about group dynamics that can be tested using variation across space and time.
- Popular Article2012The incredible adventures of a seedThe Hindu in School, 28 November
- Popular Article2012தட்டான் பார்க்கலாம் வாங்க (Lets watch Odonates)துளிர். ஜனவரி 2012. பக்கம் 16-18 / Thulir. Science monthly magazine for Kids. January Pp 7-10
தட்டான்பார்க்கலாம்வாங்க.துளிர். ஜனவரி 2012. பக்கம் 16-18. [Jeganathan, P. (2012).Thattan Pakkalam Vanga.Thulir. Science monthly magazine for Kids. January Pp 7-10(Lets watch Odonates)]
- Journal Article2012Patterns of species participation across multiple mixed-species flock types in a tropical forest in northeastern India.Journal of Natural History. 46(43-44):2749–2762.Download
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We studied mixed-species bird flocks in northeastern India to (a) develop a framework for quantifying species participation in mixed-species flocks, (b) characterize the ecology and behaviour of participant species, and (c) explore mechanisms influencing the coexistence of different mixed-species flock types. To characterize participation in mixed-species flocks, we implement a new method incorporating species abundances, minimizing potential biases in measuring participation arising from differences in the availability of flocking species. There are at least three distinct flock types in the lowland forests of northeastern India; these flock types differ in the body mass and vertical stratum use of participant species. The “core” of mixed-species flocks was composed of a species group that differed much more in their foraging method in comparison with “attendant” species. The exchange of benefits and minimization of interspecific competition might lead to, and maintain, heterogeneity in foraging methods among core species of mixed-species flocks.
- Popular Article2012காடென்ன செய்தது நமக்கு? (On what can we do for Wildlife conservation?)புதிய தலைமுறை. 1 நவம்பர் 2012. Puthiya Thalaimurai. 1st November 2012.
- Popular Article2012பூஞ்சைக்கு வந்த மவுசே! (On Fungi)புதிய தலைமுறை. 25அக்டோபர் 2012. Puthiya Thalaimurai. 25th October 2012.
- Popular Article2012களைகள் ஓய்வதில்லை. (On Invasive Alien Plants)புதிய தலைமுறை. 27 செப்டம்பர் 2012. Puthiya Thalaimurai. 27th September 2012.
- Popular Article2012நம் முகத்தில் முழித்த நரி (On Golden Jackal conservation)புதிய தலைமுறை. 20செப்டம்பர் 2012. Puthiya Thalaimurai. 20th September 2012.
- Popular Article2012The talking treeThe Hindu in School, 5 December
- Popular Article2012மரமும் மரியேனும். (On old trees and Marianne North)புதிய தலைமுறை. 18அக்டோபர் 2012. Puthiya Thalaimurai. 18th October 2012.
- Popular Article2012காட்டுக்குள்ளே ஷூட்டிங். (On impact of cinema shooting in wild habitats)புதிய தலைமுறை. 11அக்டோபர் 2012. Puthiya Thalaimurai. 11th October 2012.
- Popular Article2012என் பக்கத்து வீட்டு பழுப்புக் கீச்சான் (My friendly neighborhood Brown Shrike)தினமணி நாளிதழ் – கொண்டாட்டம் இணைப்பில். 26 பிப்ரவரி 2012. Dinamani- Tamil Newspaper. Date: 26thFebruary.
என்பக்கத்துவீட்டுபழுப்புக்கீச்சான்.தினமணிநாளிதழ் – கொண்டாட்டம்இணைப்பில். 26 பிப்ரவரி 2012. [Jeganathan, P. (2012)En pakkathu veetu pazuppu keechan.Dinamani- Tamil Newspaper. Date: 26thFebruary. (My friendly neighborhood Brown Shrike)]
- Journal Article2012Impact of vehicular traffic on large mammal use of highway-edges in southern IndiaCurrent Science 102(7): 1047-1051Download
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India’s phenomenal economic growth over the last decade has been accompanied by a much-needed expansion and improvement in transport and other infrastructure networks. While there are legally mandated assessments of the potential ecological impacts of such infrastructure projects prior to implementation, rarely are there post-implementation assessments of their real ecological impacts. In this communication, we present results of a preliminary study examining the impact of vehicular traffic on the usage of road edges by large mammals along a highway passing through Nagarahole Tiger Reserve, southern India. We estimated large mammal encounter rates at remotely triggered camera traps on two consecutive sections of the same highway – one closed to vehicular traffic and the other open to vehicles only during daytime. We observed lower encounter rates of chital, gaur and elephants at camera traps in the highway segment with higher vehicular traffic density, suggesting that these species avoided busy highways. Based on our findings, we emphasize the importance of continued ecological impact assessments of development projects to identify and mitigate unforeseen impacts. Further, an approach to development planning that integrates conservation concerns, especially where development projects coincide with ecologically critical areas, is urgently needed in India.
- Popular Article2012The mysterious cat of the high mountainsThe Hindu in School, 18 July
- Popular Article2012Islands in peril: Conservation caveats.The Hindu Magazine, Sunday 26 February 2012, page 4.
- Popular Article2012அதிரப்பள்ளியும்அமிதாபச்சனும். (On Athirapalli Waterfalls,Dr. Amitha bachan’swork on Great Hornbills)புதிய தலைமுறை. 13 செப்டம்பர் 2012. Puthiya Thalaimurai. 13th September 2012.
அதிரப்பள்ளியும்அமிதாபச்சனும். காக்கைக்குருவிஎங்கள்ஜாதிதொடர்-10. புதியதலைமுறை. 13 செப்டம்பர் 2012.[Jeganathan, P. (2012).Athirapalliyum Amitha bachanum. Kakkai Kuruvi Engal Jathi-Series, ArticleNo.10Puthiya Thalaimurai. 13th September 2012. (On Athirapalli Waterfalls,Dr. Amitha bachan’swork on Great Hornbills)]
- Popular Article2012இடைவெளியும் இடையூறும் (Canopy gaps and obstacles: Canopy gaps above the forest roads and their impact on arboreal mammals of Western Ghats)Dinamani Tamil Newspaper. 29 January 2012.
இடைவெளியும் இடையூறும். தினமணி நாளிதழ் – கொண்டாட்டம் இணைப்பில். 29 ஜனவரி 2012. 3ம் பக்கம். [Jeganathan, P. (2012). Idaiveliyum Idayoorum. Dinamani- Tamil Newspaper. Date: 29th January (Canopy gaps and obstacles: Canopy gaps above the forest roads and their impact on arboreal mammals of Western Ghats) ]
Link for this article here.
- Popular Article2012காக்கா…காக்க...(On Crows)புதிய தலைமுறை. 12ஜூலை 2012 Puthiya Thalaimurai. 12th July 2012
- Popular Article2012காப்பிநல்லதா?டீநல்லதா? (On best practices in sustainable agriculture of Coffee and Tea)புதிய தலைமுறை. 6 செப்டம்பர் 2012. Puthiya Thalaimurai. 6th September 2012.
காப்பிநல்லதா? டீநல்லதா?. காக்கைக்குருவிஎங்கள்ஜாதிதொடர்-9. புதியதலைமுறை. 6 செப்டம்பர் 2012.[Jeganathan, P. (2012).Kappi nallatha? Tea nallatha?. Kakkai Kuruvi Engal Jathi-Series, Article No.9. Puthiya Thalaimurai. 6th September 2012. (On best practices in sustainable agriculture of Coffee and Tea)]
- Popular Article2012சின்னஞ்சிறுகுருவே…(On Ants)புதிய தலைமுறை. 26ஜூலை 2012. Puthiya Thalaimurai. 26th July 2012.