- Report2013MigrantWatch 2007-2012Unpublished report, Citizen Science Programme, National Centre for Biological Sciences.
- Journal Article2013Can wetlands maintained for human use also help conserve biodiversity? Landscape–scale patterns of bird use of wetlands in an agricultural landscape in north IndiaBiological Conservation 168: 49-56. http://dx.doi.org/10.1016/j.biocon.2013.09.016
Wetlands in tropical agricultural landscapes are maintained largely by local institutions explicitly for human use, which is assumed to deter biodiversity. Conservation efforts have been biased towards protecting large wetlands that are assumed to be adequate to conserve the majority of species of focal taxa, usually birds. These assumptions remain untested, and landscape-scale conservation planning for wetlands is largely absent, as is a generalised understanding of wetland use by focal taxa. We designed a landscape-scale survey to understand patterns and processes determining beta diversity of birds using agricultural wetlands in south-western Uttar Pradesh, India where wetlands have experienced prolonged and intensive human use for several centuries. Observed bird species richness (99 species in 28 wetlands) is the highest known for any agricultural landscape in south Asia signifying that even intensive human use of wetlands does not necessarily deter their ability to retain biodiversity. Birds exhibited strong scale
dependent wetland use underscoring the need to conserve wetlands of varying sizes and at varying densities on the landscape. Beta diversity was due largely to species turnover (0.877) with minimal effect due to nestedness (0.055) suggesting that conserving a few large wetlands will not adequately meet goals of conserving the majority of wetland bird species. Prevailing assumptions regarding biodiversity conservation in tropical agricultural wetlands require being revised, and a landscape-scale approach that incorporates ecological realities is needed. Incorporating local institutions alongside formal protectionist methods offer a potential win–win situation to maximise conservation of biodiversity in tropical agricultural wetlands.
- Popular Article2013Living in an extreme worldThe Hindu, Editorial Page, 13 July 2013, page 10.
There is compelling evidence to show that man weather-related disasters are not chance occurrences but are a result of human activities that have altered our atmosphere.
- Popular Article2013An apology to the Iyerpadi gentlemanThe Hindu Magazine, 14 April 2013, page 4.
- Journal Article2013Complex ecological pathways underlie perceptions of conflict between green turtles and fishers in the Lakshadweep Islands.Biological Conservation 167: 25-34
Managing human–wildlife conflict is often complicated by apparent mismatches between community perceptions and measures of directly incurred losses. Fishers in Agatti Island (Lakshadweep, India) associate recent increases in green turtle (Chelonia mydas) populations with declining fish catches, resulting in targeted killing of turtles. We compared fisher perceptions in Agatti with a very similar atoll, Kadmat, with much lower turtle densities. Nearly 90% of Agatti fishers interviewed blamed turtles for declining catch compared with 20% in Kadmat and proposed two mechanisms for this decline: direct interference (e.g., turtles damaged gear) which we define as first order conflict, and indirect mechanisms (second order conflict): turtles overgrazed seagrasses, thereby reducing fish catch. We evaluated the magnitude of gear loss with interviews and tested proposed indirect mechanisms with a turtle density gradient, before–after comparisons (taking advantage of an increase in turtles in Kadmat and concurrent decrease in Agatti) and a natural herbivore exclosure. These complementary approaches supported fisher-pro- posed second-order mechanisms: at high densities, turtles heavily grazed seagrasses, significantly reduced canopy heights, lowered fish recruit abundance, food fish biomass and catch. Estimates of losses incurred in Agatti show that first-order conflict cost fishers USD 0.6 fisher-1 year1, while second-order pathways accounted for USD 887 fisher-1 year-1. Our results show that local perceptions are fueled by often-complex mechanisms that, though not always straightforward to measure, are very important in generating conflict. Reconciling the human–wildlife interface requires an adequate accounting of direct and indirect mechanisms to more completely reflect true losses communities bear for living with wildlife.
- Book Chapter2013Arunachal macaque Macaca munzala (Sinha, Datta, Madhusudan and Mishra 2005)Pages 198-210 in A. J. T. Johnsingh & N. Manjrekar (editors) Mammals of South Asia – Volume 1. Universities Press, Hyderabad, India
- Popular Article2013Fungi forayThe Hindu, Young World, 29th January 2013.
Jeganathan, P. (2013). Fungi foray. The Hindu, Young World, 29th January 2013. http://www.thehindu.com/life-and-style/kids/fungi-foray/article4353151.ece
- Popular Article2013Development minus green shootsThe Hindu, 13 February 2013
By exempting some projects on forest land from gram sabha consent, the government has undermined the rights of local communities and their crucial role in protecting the environment.
Read further here
- Popular Article2012Twinkle, twinkle, little batThe Hindu in School 2 May
- Journal Article2012Distance-related thresholds and influence of the 2004 tsunami on damage and recovery patterns of coral reefs in the Nicobar IslandsCurrent Science 102:1199–1205
The earthquake and tsunami of 2004 resulted in the devastation of marine and coastal ecosystems across the Indian Ocean. However, without adequate baseline information it has been difficult to properly gauge its full impact. The reefs of the Nicobar Islands in the Bay of Bengal lie on a path that ranges from 190 to 500 km from Banda Aceh, the epicentre of the 2004 tsunami. In 2008, we recorded benthic damage as a result of the tsunami to reefs off 14 Nicobar Islands across a gradient of distance from the epicentre. A clear pattern was observed in the demographic structure of the most abundant coral genera, Acropora and Porites across the distance gradient. Significantly, for the largest coral individuals of both genera (> 50 cm diameter), there were distinct threshold effects – their abundance declining dramatically in reefs closer than 350 km from the epicentre. Corals between 20 and 50 cm diameter also increased with distance from the epicentre, but in a more linear fashion. Smaller size classes either showed no apparent trend (Acropora) or decreased linearly (Porites) with distance. These gen- era represent very different life-history strategies: Acropora is fast-growing and highly susceptible to a range of disturbances, while Porites typically grows slowly but is resistant to disturbance. The fact that both genera showed similar thresholds indicates that, close to the epicentre, the impact of the earthquake and tsunami was large enough to override any species- specific resistance. Also, algal cover was also much higher than at locations further north, linked to higher coral mortality at these locations. However, the fact that smaller size class coral individuals were rela- tively abundant and even increased close to the ep centre indicates possible paths of reef recovery after the catastrophe.
- Journal Article2012To eat and not be eaten: modelling resources and safety in multi-species animal groups.PLoS ONE. 7(7): e42071.Download
PDF, 291 KB
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 sheep that isn'tThe Hindu in School, 20 June
- 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)]
- Popular Article2012Crows, but not quite...The Hindu in School, 4 July
- Popular Article2012Gowa of Ladakh!The Hindu in School, 11 July
- Popular Article2012Attack of the killer fungusThe Hindu in School, 1 August
- Popular Article2012Friendly fungiThe Hindu in School, 8 August
- Popular Article2012Winter visitors from far awayThe Hindu in School, 16 October
- Popular Article2012The singing farmers of the forestThe Hindu in School, 21 November
- Popular Article2012The incredible adventures of a seedThe Hindu in School, 28 November