- Journal Article2019Large frugivores matter: insights from network and seed dispersal effectiveness approachesJournal of Animal Ecology ( https://doi.org/10.1111/1365-2656.13005)Download
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We evaluated the role of large avian frugivores in a plant‐disperser community by a) determining whether the plant‐disperser community was modular, with a distinct community of large frugivores (thereby highlighting their importance), b) determining relative qualitative and quantitative roles played by large‐bodied frugivores vis‐à‐vis other frugivores and c) determining impacts of large‐bodied frugivore loss on the plant‐disperser community. The study was carried at a tropical forest site in north‐east India which is part of the Eastern Himalaya Biodiversity Hotspot. We collected tree watch data (2055 h) from 46 tree species, which represented 85% of tree species that are predominantly bird‐dispersed in the area. We found that the plant‐disperser community was modular, with a distinct module of large‐seeded tree species and large frugivores. Intermediate‐sized frugivores such as barbets and bulbuls were the most connected, while large‐sized frugivores, such as hornbills and imperial‐pigeons were moderately well‐connected. Qualitative and quantitative roles played by different dispersers varied across the gradient of frugivore body size. Hornbills, the largest avian frugivores, consumed a significantly greater number of fruits and swallowed larger proportions of fruits compared to other avian groups. In comparison to similar‐sized frugivores, imperial‐pigeons fed on larger‐sized fruits, highlighting their importance for dispersal of large‐seeded plants. Under simulated extinction scenarios, larger extinction cascades weren't necessarily caused by larger frugivores, however, extinctions of certain large‐bodied frugivores (hornbills, imperial‐pigeons) caused extinction cascades. Integrating information from networks and seed dispersal effectiveness approaches enabled a better understanding of large frugivore role in a plant‐disperser community. While large‐bodied frugivores may not be playing a central role in plant‐disperser communities, they are crucial as seed dispersal service providers for large‐seeded plants. In conjunction with the reported local extinctions of large frugivores like hornbills from the south Asian region, this study's findings highlight the irreplaceable quantitative and qualitative impacts that tropical plant communities are likely to experience in the future.
- Popular Article2018Spiders: The weavers and stalkers amongst usiWonder Issue 4, Jan 2018
A piece on spiders for iWonder, an Indian magazine for science middle school teachers. Fun and fascinating facts about spiders to talk and discuss about in the classroom. Lots of activities that teachers can do with students in and outside the class room.
- Book2018Off to see spiders!StoryWeaver by Pratham Books
Kaveri and Shivi go looking for spiders, along with their friend Shama. A story for young children commissioned and published by Pratham Books', StoryWeaver platform.
Guest editor: Bijal Vachharajani, Art: Pia Meenakshi
- Journal Article2018The role of artificial habitats and rainfall patterns in the unseasonal nesting of Sarus Cranes (Antigone antigone) in south AsiaWaterbirds 41(1): 80-86.
Sarus Cranes (Antigone antigone) in south Asia breed during the rainy season (monsoon), with few nests initiated outside of the monsoon. Several hypothesis have been put forth to explain the unseasonal nesting outside the monsoon, but a careful evaluation of the hypotheses has been absent. Using a multi-year (2004-2017), multi-scale (four Indian states) data set, this study explored the factors potentially responsible for unseasonal nesting by Sarus Cranes. Nests outside the monsoon were very rare (0.3% of all nests) and were initiated when Sarus Crane pairs were in areas with artificial water sources (irrigation canals or reservoirs) or faced abnormal monsoonal conditions. Unseasonal nests were initiated only when breeding pairs had been unsuccessful in raising chicks in the previous primary nesting season. Altered cropping patterns associated with increased artificial irrigation and changing rainfall patterns appear responsible for unseasonal nesting in Sarus Cranes. Nesting of this species outside the monsoon may increase in response to the increasing changes in cropping patterns and changing rainfall conditions.
- Journal Article2018Temporal variations in patterns of Escherichia coli strain diversity and antimicrobial resistance in the migrant Egyptian VultureInfection Ecology and Epidemeology 8:1, 1450590.
Aims: Multiple antimicrobial resistance in Escherichia coli of wild vertebrates is a global concern with scarce assessments on the subject from developing countries that have high human-wild species interactions. We studied the ecology of E. coli in a wintering population of Egyptian Vultures in India to understand temporal changes in both E. coli strains and patterns of antimicrobial resistance.
Methods and Results: We ribotyped E. coli strains and assessed antimicrobial resistance from wintering vultures at a highly synanthropic carcass dump in north-west India. Both E. coli prevalence (90.32%) and resistance to multiple antimicrobials (71.43%) were very high. Clear temporal patterns were apparent. Diversity of strains changed and homogenized at the end of the Vultures’ wintering period, while the resistance pattern showed significantly difference inter-annually, as well as between arrival and departing individuals within a wintering cycle.
Significance of study: The carcass dump environment altered both E. coli strains and multiple antimicrobial resistance in migratory Egyptian Vultures within a season. Long-distance migratory species could therefore disseminate resistant E. coli strains across broad geographical scales rendering regional mitigation strategies to control multiple antimicrobial resistance in bacteria ineffective.
- Popular Article2018Meet the world’s smallest wild catThe Hindu, In school, March 18 2018
A peek into the life of the rusty-spotted cat, an elusive feline found in the forests of India.
- Popular Article2018Flexible Fish
- Popular Article2018Q&A: Spider Insider with Vena Kapoor
- Popular Article2018Ornithology and Graphic Design: What's the Connection?
- Report2018Understanding distribution, population density and conservation status of the endemic and threatened Ladakh urial Ovis orientalis vignei
- Book Chapter2018Living with Snow Leopards: a pluralistic approach to conservationIn Conservation from the Margins. (Eds) Umesh Srinivasan & Nandini Velho. Orient Blackswan
- Poster2018Birds Around Us
- Report2018Population assessment of the Nilgiri tahr (Nilgiritragus hylocrius) using the Double-observer Survey method in the Anamalai Tiger ReserveTechnical Report, Nature Conservation Foundation, Mysore, India
- Journal Article2018Hornbill Watch: A citizen science initiative for Indian hornbillsIndian Birds, 14:65-70Download
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Hornbills are conspicuous and well-known birds with nine species occurring in India. While several hornbill species have been studied extensively in some parts of India, there is a knowledge gap about their distribution, population size, and adaptations to rapidly changing habitats. Most research and conservation efforts are often focused on single or few species within protected areas. Hornbill Watch (henceforth, HW) is an online platform created specifically to record public sightings of hornbills from anywhere in India. The idea is to encourage birders, nature enthusiasts, and photographers to share information on hornbill presence, behaviour, and conservation-related issues. The main objective is to generate baseline information using sight records and enable long-term monitoring of these species by encouraging citizen participation. HW was launched in June 2014, and up to February 2017 had received 938 records from 430 contributors across India, from 26 States and three Union Territories. States from where most sightings were reported were Karnataka, Maharashtra, Tamil Nadu, Assam, and Arunachal Pradesh. Species were reported from both inside (41%), and outside Protected Areas (59%; henceforth, PA). Hornbills were reported from 70 PAs. Fifty-one records of nesting were reported for all species from inside and outside PAs, while 27 records of communal roosting were reported for some species. The data obtained thus far has yielded some useful information and insights,and has the potential for enhancing our understanding of current hornbill distribution patterns, and for identifying important sites for conservation/protection.
- Journal Article2018Breeding biology of Great Hornbill Buceros bicornis in tropical rainforest and human-modified plantation landscape in Western Ghats, IndiaOrnithological Science, 17:205-216Download
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Loss of mature tropical forests to agricultural expansion often creates landscapes with forest fragments embedded within a matrix of human-modified habitats and land uses. Such habitat fragmentation may be detrimental to species with specialized habitat and foraging requirements and their ability to persist in such landscapes may depend on their adaptability to habitat modification. Great Hornbills Buceros bicornis, among the largest birds in Asian tropical rainforests, depend on large trees for nesting and a diverse array of patchily distributed fruiting trees. In the human-modified landscape of the Anamalai Hills, India, we compared the breeding biology and nesting behaviour of Great Hornbills in contiguous rainforest (N=3 nests) and in modified habitat consisting of coffee plantations and rainforest fragments (N=5 nests). The nesting cycle of seven of the eight nests monitored varied between 114 and 130 days. Nest provisioning behaviour was similar in contiguous forest and modified habitat in terms of visitation and food delivery rates, but visitation tended to be higher and food delivery rate lower during the nestling phase than during incubation. As expected, tree density and native food plant diversity were lower in modified habitat than in continuous forest. The diversity of food provisioned was lower in modified habitat with a 57.5% dietary overlap with contiguous forest. Hornbills in the modified habitat of coffee plantations used non-native tree species for nesting and foraging, indicating their adaptability to modified landscapes.
- Report2018Understanding impacts of hornbill loss on plants.Final report submitted to Arunachal Pradesh Forest Department, Itanagar, Arunachal Pradesh towards completion of the research project titled “Understanding Impacts of Hornbill Loss on Plants”.Download
PDF, 21.2 MB
While large avian frugivores are known to be key dispersers for large-seeded plants, their role in the wider plant-disperser networks is still poorly known. In this study, we evaluate the role of large avian frugivores in plant-disperser communities using network and seed dispersal effectiveness approaches in a tropical forest site in north-east India. We systematically-collected tree watch data from 46 plant species, representing 85 percent of typically bird-dispersed plant species, spanning over 2055 h. We found that the plant-disperser community was modular with a distinct community of large-sized seed plants and frugivores. While intermediate-sized birds such as barbets and bulbuls were the most connected, large-sized dispersers such as hornbills and Imperial-pigeons were moderately well-connected. Imperial-pigeons consistently fed on large-sized fruits, highlighting their importance for dispersal of large-seeded plants. In addition to frugivore-fruit size matching, frugivore dietary choices might play an important role in governing the organization of modules. There was a gradient in qualitative and quantitative roles played by different dispersers, with hornbills removing significantly larger number of fruits and consistently swallowing larger proportions of fruits as compared to other avian groups. Under simulated extinction scenarios, observed networks were far less resilient to disperser loss along a gradient of body size from large to small as compared to extinctions that were random or based on rarity. Given the paucity of information on plant-disperser networks from the South Asian region and reported local extinctions of large frugivores like hornbills, this study is important in highlighting that loss of large avian frugivores might have irreplaceable quantitative and qualitative damages to plant communities.
- Journal Article2018eBird in Asia: standardised tools for birdwatchersBirdingASIA, 29:105-108
- Journal Article2018Seasonal variation in wildlife roadkills in plantations and tropical rainforest in the Anamalai Hills, Western Ghats, IndiaCurrent Science. 114(3): 619-626.