Theses and Dissertations
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Item Tadpoles with a Trick : Overwintering Ecology of Tadpoles in a Himalayan Stream, Uttarakhand India(Wildlife Institute of India, Dehradun, 2021) Jithin, V.; Das, Abhijit; Johnson, J.A.Overwintering is a unique phenomenon of delaying metamorphosis in amphibian larvae at low temperature conditions prevailing at high elevation and latitude. This study is first of its kind in India to look at selected ecological aspects of overwintering tadpoles of Nanorana spp. in a Himalayan streamItem Assessing the Impact of Traditional Practice of Frog Consumption Amphibian Population from Mizoram India Culture -Nat(Wildlife Institute of India, Dehradun, 2021) Malsawmdawngliana; Das, Abhijit; Kawlni, Lallianpuii; Lalronunga, SamuelCultural practices have shaped the natural resources around the area in all parts of the world. The traditional practices involving wildlife and their meat as food resources is widely practised by many tribes of the world. Such practice also involves amphibian exploitation as food, one of the critical reasons for the decline in the global amphibian population. Such practice is widespread in the Northeast part of India, including Mizoram. However, the population-level impact of such traditional practice is poorly known. The study was carried out in the buffer and core zone of Dampa Tiger Reserve (DTR) to assess the abundance and species richness. We surveyed four villages around DTR to see how the pattern of frog consumption by the local communities. The study tried to understand how the species diversity and abundance is affected by the off-take of frogs for food in the study area. Time constrained nocturnal Visual Encounter Survey method was used to see the species composition and abundances in the study area. Random sampling using questionnaires and interactions were used to see the frogs’ consumption pattern, medicinal use and preferred species for food of the local communities in the study area.Item Distribution Pattern of Amphibians in Megamalai Landscape, Western Ghats, Tamil Nadu(SACON, 2011) Srinivas, G.; Bhupathy, S.Amphibians. in particular anurans, contribute a significant proportion or the vertebrate biomass in all the terrestrial and freshwater ecosystems. They function as important predator and prey species. However, studies focusing on ecology of these taxa in Indian subcontinent arc scanty. The present study had the following objectives: (1) understand the population of amphibians in the Megamalai landsc;lpe. (2) study the distribution pattern of amphibians with respect to elevation categories and vegetation types and (3) suggest conservation measures. The present study was carried out in Megamalai Hills of Theni Forest Division. From December 2006 November 2008. In the present study. three belt transects Mavadi,. Suruli and Vellimalai were laid from hilltop to the bottom stratified at 200m intervalItem POPULATION AND RESOURCE UTILISATION BY REPTILES IN UPPER NILGIRIS, NILGIRI BIOSPHERE RESERVE, WESTERN GHATS, INDIA(SACON, 2005) ARMSTRONG, A. MATHEWS NIXON; Bhupathy, SHerpetofauna (reptiles and amphibians) are important components of both terrestrial and wetland ecosystems as they play a major role in energy flow and nutrient cycling. Both of them are also excellent indicators of environmental degradation. Being poikilotherms, reptiles tend to partition time and space more often than homeotherms as their physiology and behaviour are closely linked to environmental conditions. However, quantitative data on the population and resource use by reptiles are scanty in India. Resource use can be studied with respect to the three most often recognized niche axes: spatial (habitat use), temporal (activity period) and trophic (food). Herpetofauna of India, one of the most diverse taxa, is poorly known regarding their ecology and population characteristics. Major objectives of this study was to (1) assess the population status of reptiles and factors determining their distribution in various habitats of Upper Nilgiri plateau (2) determine the habitat use and food habits of reptiles, and (3) to understand the resource use at spatio-temporal and trophic levels by reptiles in Upper Nilgiris.Item Toads on Roads : Effect of Linear Barrier on the Movement Ecology of Common Asian Toad (Duttaphrynus melanostictus)(Wildlife Institute of India, Dehradun, 2015) Sharma, Preeti; Das, Abhijit; Rajvanshi, AshaAmphibians in India are threatened by population decline and extinction. Conservation efforts are hindered by scanty knowledge on their movement pattern, habitat use and dispersal. Thus, I conducted first ever radio telemetry study on an Indian Amphibian species in Krishnan kovil, a village in Virudunagar district in Tamil Nadu state of India. The study was conducted over a stretch of 1.5 km on both sides of Kollam-Thirumangalam highway (NH 208). The objective was to know if there is any effect of road on the movement and population abundance of Duttaphrynus melanostictus, commonly known as common Asian toad. Reason for selecting a widespread perianthropic species is that such species can better indicate how gene flow is structured in an urban landscape. Total 9 adult individuals (5 ~ and 4 c)I) were tracked ranging between 12 to 41 days from February 1 - April 9, 2015. Findings of the study revealed that NH 208 has a significant effect (estimate 0.007589; standard error 0.003108) on linear displacement of toads that increases away from the road. However in case of village roads the linear displacements were higher near to the roads (estimate -0.01569; standard error 0.002977). This indicates that NH may be affecting the movement of amphibians as a potential physical barrier. However, village roads still seem to be permeable by the toads as they are using it for movement. Orientation data shows no significant orientation (Chi square value 1.19, P value 0.55) of movement of the toads. However, field observations show that movement of toads with NH was always along or away but never across it. Home range estimates show that animal # 6 (NHR6M) used largest home range of 4262.92 sq. meters and showed maximum linear displacement in one night up to 333m. Another aspect of the study was to determine effect of NH on population abundance of common Asian toad. I conducted mark recapture studies in one hectare plot at three sites. The abundance estimates are 228.97 (S.E. 14.09) individuals per hector for site 1, 125.59 (S.E. 9.68) individuals per hector for site 2, 365.94 (S.E. 46.85) individuals per hector for site 3. Abundance estimates at the 3 sites show an increasing trend with the increasing perpendicular distance from the NH. This indicates that the road may have an effect on the population of Duttaphrunus melanostictus. The study is limited to only one non breeding season (3 months), thus, is biased towards movement in less activity period. The study provides hitherto unknown information on toad movement with respect to linear barrier. Such studies are useful in developing realistic, predictive models useful for mitigation and restoration of dispersal corridors in a rapidly changing urban landscape. Results of this first ever amphibian radio telemetry study from India add to a new dimension in Indian amphibian research- beyond taxonomy.Item Impacts of Habitat Conversion on the Leaf Litter Anuran Community of Varagaliar, Western Ghats(Wildlife Institute of India, Dehradun, 1995) Saravanakumar, S.U.; Chellam, RaviItem Effect of Habitat Alteration On Herpetofaunal Assemblages on Evergreen Forest in Mizoram, North-East India(Wildlife Institute of India, Dehradun, 1999) Choudhury, B.C.; Panwar, Samraat; Rawat, G.S.The response of frogs and Lizards to habitat alteration was studied in South Mizoram. Chronoseres were selected such that two successional gradient were represented- jhum fallows regenerating to mature forest. and jhum allows converted to teak plantations. Herpetofauna were sampled by three techniques- strip transects, pitfall trapping. and systematic searching. Species richness of herpetofauna increased along the jhum-mature forest gradient. However. teak plantation had a depauperate herpetofauna. similar in composition to the 1- year jhul1l fallows. All frogs and lizards were c1assilied into 6 guilds on the basis of their activity period (diurnal or nocturnal) along with whether they were terrestrial , arboreoterrestrial or arboreal. Analysis of the strip-transect data showed that there were distinct differences in the distribution and abundance patterns of diurnal and nocturnal species. To examine patterns, multidimensional scaling (MDS) was used for indirect gradient analysis in two ways- firstly to summarize differences between sites and secondly, to explore possible associations between herpetofaunal guilds and habitat parameters across categories. The MDS differentiated two different groups of habitat variables. One group makes up the gross structural components of the habitats. while the other represents microhabitat parameters. All guilds were more strongly associated with trends in microhabitat distribution. than macrohabitat-parameters. while species richness showed diffuse associations with habitat parameters. The assemblages in the I to 10 yr. jhum fallows and teak plantations were dominated by a set of terrestrial and arboreo-terrestrial lizard species. Most of those species are distributed widely. either in the Indian subcontinent. or further east and south. into South-east Asia. On the other hand. a number of frogs and some lizards were restricted to mature forest. Most of these species are restricted either to North-east India. or to the study area itself. and some are apparently hitherto undescribed species. The fact that so many narrowly distributed species were found in mature forest has obvious conservation implications. Overall. the results suggest that in a mosaic of habitats resulting from jhum-cultivation. even remnants of primary forest may be of immense importance for persistence and recolonization by mature forest herpetofauna. Teak plantations offer a very marginal habitat for a large set of herpetofauna. even after a long period of growth.