Technical Reports/Books/Manuals
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Item Ecology of two endemic turtles in the Western Ghats(Wildlife Institute of India, Dehradun, 2010) Vasudevan, K.; Pandav, B.; Deepak, V.This project was initiated on the 16th January 2006 with an aim to generate natural history information on two out of the three endemic species of terrestrial turtles. India has 28 species of freshwater turtles and tortoises, of them three species are endemic. The endemic species: Caneturtle, Vijayachelys silvatica; Travancore tortoise Indotestudo travancorica; Leith’s softshell Nilssonia leithii, are restricted to the southern peninsula and the Western Ghats. In this study the focal species were the Cane turtle and the Travancore tortoise which had their distribution in the Western Ghats. The objectives of the project were (i) to estimate the population density of Travancore tortoise and cane turtle in a fragmented landscape; (ii) to quantify the diet of these two species and describe the feeding ecology with respect to their role in seed dispersal; (iii) to identify threats to the turtle population based on their habitat use ranging pattern and food habits and recommend measures for their conservation; (iv) to carry out a survey of these two species along the Western Ghats to ascertain the exact distribution in the context of Protected area network in the region. The study employed methods to study the population, diet and ranging patterns of the Cane turtle and the Travancore tortoise in Anamalai and Parambikulam Tiger Reserves. In the case of Travancore tortoise, the animals were searched on forest trails scattered in the reserves and repeated over three years to determine the proportion of area occupied accounting for imperfect detections. These surveys revealed that about 82% of the area surveyed is occupied by the tortoise, suggesting that the reserves hold sizeable population of the tortoise. The occupancy of the Travancore tortoise was negatively influenced by anthropogenic disturbance levels and positively influenced by the availability of water bodies and grass marsh in different sites. Only 35% of the sites occupied by the species resulted in detections, suggesting that it was cryptic. The important constituents of its diet were grass, other plant matter, invertebrates and other animal matter. The vayal (grass openings within woodland) habitat might be crucial for foraging by Travancore tortoise. The five individuals that were radio-tagged used an area from 5 to 35 ha covering evergreen, bamboo and open scurb-grass marshes. The animals spent about 98% of their time under leaf litter, logs, rocks crevices, tree holes, termite or pangolin burrows, bamboo tickets and under grass. In the case of cane turtle, various search methods employed did not yield detections and therefore, an intensive area was combed intensively. This resulted in detections of the elusive cane turtle. During the study spanning over four years, 42 ha of the evergreen forests in the reserve resulted in sightings of 27 different individuals of the cane turtle. This suggests that the species occurs in high density in the evergreen forests. Six cane turtles were fixed with radio-transmitters and monitored for two years. They used an area from 3.5 to 14.2 ha restricted to the evergreen forests alone. They also had extensive overlap in their home-ranges, suggesting no territoriality in the species. The movement of the animals were influenced by temperature and rainfall in the intensive study area. Diet of the species consisted of forest floor invertebrates, seeds and other plant material. The field observations on feeding on a large land snail and aggressive encounters between males of the cane turtle were the highlights of the study on the species. A survey of the three endemic species of turtles was taken up in the fifth year of the project. The survey involved visiting 12 sites in the states of Karnataka and Tamil Nadu. The potential sites where the species might be found were visited and the locals were interviewed in order to document the occurrence of the species. This resulted in one new locality record for cane turtle and two new records for Travancore tortoise. The Leith’s softshell was reported from five different locations in Karnataka and Tamil Nadu based on the interviews with locals. The sites occupied by the species were located within and outside protected areas. So far the study has resulted in three peer reviewed publications and two presentations in international conference. Based on the findings of the study it could be inferred that the Travancore tortoise is sensitive to human disturbance. This might be the consequence of exploitation of the animal by the locals in the reserves where the study was conducted. It is not uncommon to find locals using domesticogs during their forays into the forest. We speculate that there is some level of subsistence exploitation of the species in the region. The behaviour and ranging pattern of the species make them cryptic for detection by humans, but vulnerable to detection by domestic dogs. The study revealed that there is poor awareness among wildlife protection staff in the reserves on the species in general. Increasing the awareness of the staff could result in curbing subsistence exploitation of the species in the reserves. The vayals in the reserve are crucial habitats for the species; therefore, their protection and monitoring should be of importance for the persistence of the tortoise population. In the case the cane turtle, contrary to our initial expectations they survive in high densities (60 individuals in 1 sq. km) in the middle and low elevation evergreen forests (between 10 – 1000 m above mean sea level). The Karian Shola National Park is having a large population of this species which is of importance of the management of the protected area. The species is extremely stenotypic, showing strong preference to a narrow range of microclimatic variation prevailing in evergreen forests that are below 1000 m elevation in the Western Ghats. This indicates that the low elevation evergreen forest areas are crucial habitats for the species. Our intensive study on the species spanning over four years did not yield much information on the reproductive ecology of the species, because of their secretive lives. We recommend studies on the reproductive biology of the species, which might be important in the context of conservation breeding of the species. In the case of Leith’s softshell, we suggest extensive surveys to document the distribution, the status of population and, the genetic and morphological variation in the populations in peninsular India.Item Status survey and conservation of the Himalayan salamander Tylototriton verrucosus in the Eastern Himalayas(Wildlife Institute of India, Dehradun, 2014) Vasudevan, K.; Kumar, R.S.; Sengupta, S.The Himalayan crocodile salamander Tylototriton verrucosus was first described in 1871 from the Nantin, Momien and Hotha valleys, in western Yunnan, China. Subsequently, there have been sporadic reports of the species from Nepal, Bhutan, India, Burma, China, Thailand and Vietnam. At present, the species is known to have a vast geographic distribution and thereby assigned as ‘Least Concern’ by the IUCN. This species shows considerable morphological overlap with 13 other known con-generics from the region, and is now considered to be a species complex. To predict the distribution of the species in India field surveys were conducted during the breeding period between May and August 2012 in parts of northern West Bengal State and northeast India. Along with the data from field surveys, historical data was compiled from published literature, Natural History Museum collections and from GBIF portal. Using ecological niche mapping tool – MAXENT 3.3.3k predictive modeling of the species distribution was done. For the analysis, 61 locations collected from field surveys in northern West Bengal and Manipur State, and 50 locations from archives were used. Fifty percent of the locations were used as training sites for the analysis. Using prior knowledge of the species a candidate set of 19 environmental layers (~1 km2 resolution) from WORLDCLIM 1.4 was used for the analysis. The variables were: precipitation, minimum and maximum temperature for six months, when the species is active during the year, and altitude. The predicted geographic distribution shows the salamander populations to occur in small, discrete sites in mountain ranges of South East Asia. It is hypothesized that historical factors to may have led to the observed pattern in its geographic distribution.Item Conservation strategy and action plan for the marine turtles and their habitats in Puducherry(Wildlife Institute of India, Dehradun, 2017) Sivakumar, K.; Senthil Kumar, S.; Kumar, R.S.; Ramesh, C.; Adhavan, D.; Hatkar, P.; Bagaria, Priyamvada; Kakadia, D.; Jyothi, P.Puducherry, is a small but beautiful Union Territory of India, located along the southern east coast of India with coastline of 45 km. This coastline is being used for nesting of sea turtles, especially Olive Ridley and Green Sea turtles. Their sporadic nesting is at peak during November to February along Puducherry and Karaikal coasts. High sporadic nesting of sea turtles were observed on the beaches along Nallavadu/Moorthikuppam villages (Puducherry) and beaches around Arasalar River (Karaikal), therefore, these two beaches have been identified as ‘Important Sea turtle Habitats of Puducherry’ and recommended to be declared as the ‘Community or Conservation Reserves’ as per the Wildlife (Protection) Act, 1972. Further, it is recommended to manage these two beaches with active participation of local communities by promoting the turtle conservation as well as eco-tourism. Land use/land cover patterns along the coastal areas of Puducherry and Karailkal was significantly changed between 2004 and 2015. Larger portion of agricultural lands adjoining to nesting beach were converted for aquaculture and built up areas, that deterred sea turtles use of beaches for nesting. It was also found that arable lands along turtle nesting beaches were shrunk due to demand from other developing sectors such as aquaculture, tourism and real estate. Therefore, it is proposed to declare remaining critical sea turtle nesting beaches of Puducherry such as Nallavadu, Pannithittu, Narambi and Moorthikuppam villages (Puducherry) and beaches around Arasalar River (Karaikal) as ‘Eco-sensitive Zones’ under relevant sections of the Environment (Protection) Act, 1986. A significant proportion of world's Olive Ridley population migrates every winter from the Southern Indian ocean (near Sri Lanka) to Odisha, where they do mass nesting. Puducherry coastline is being used as a migratory route by these sea turtles. Off coast of Puducherry especially 60 - 400 km stretch from the shore were largely used by the migratory sea turtles during the month of October to April in every year. Further, few hundreds of sea turtles that are seems to be resident to Puducherry off coast, breed and nest along its coasts. Some of these breeding sea turtles have been incidentally killed by fishing nets especially between December and January. Turtles eggs are also predated by dogs and other animals on the shore. Therefore, it is proposed to strengthen the ongoing ex-situ turtle conservation programme of State Forest Department by facilitating the safe hatchings of turtle eggs through the artificial hatcheries. In this context, it is recommended to create two permanent hatcheries in these proposed two conservation reserves and involve local communities in the turtle monitoring and conservation programme. Moreover, Turtle Excluder Device (TED) should be made mandatory for all trawlers fishing along the Puducherry coasts. Beach erosion due to natural phenomena as well as urbanization, have reduced the nesting habitats and resulted in a drastic reduction in sea turtle nesting along Puducherry coast. Moreover, beach armouring with exotic plantations, artificial illumination and tourism are few other threats to the nesting beaches and hatchlings. Hence, it is recommended to continuously monitor the nesting beaches and avoid exotic plantation within 500 m from the high tide line and also manage vegetations on the beaches. Further, it is recommended to constitute an Authority with multi-stakeholders to protect the beaches and its biodiversity of Puducherry. It is also suggested to create a ‘Puducherry Sea Turtle and Coastal Research and Monitoring Cell’ at the Forest Department for the long term conservation of coastal biodiversity and livelihoods of people of Puducherry.Item Assessment of amphibians and reptilian diversity along Ganga river : progress report(Wildlife Institute of India, Dehradun, 2021) Das, Abhijit; Hussain, S.A.; Johnson, J.A.; Boruah, BitupanIn the present study an attempt has been made to survey the herpetofaunal diversity along Ganga River. The objectives of the study are to determine the species richness and diversity of herpetofauna along Ganga and Alaknanda river ii. To map the distribution of herpetofaunal species along Ganga and Alaknanda river iii. To study the reproductive biology of threatened amphibian species of the Ganga River BasinItem Tracking the nearshore and migratory movement of Olive Ridley sea turtles occurring in the coastal waters of Maharashtra(Wildlife Institute of India, Dehradun, 2024) Mudliar, Mohit M.; Kumar, R. SureshThis tracking study has been successful in creating awareness about olive ridley sea turtles through extensive media coverage on tagging and movement updates. Even with a small number of tagged turtles, it also provided crucial information on the movement and diving ecology of this lesser-studied population. Most importantly, the patterns of movement from this study suggests that turtles nesting on the Maharashtra coast comprise two foraging populations. Firstly, those that are resident to the Arabian Sea and the others from the Sri Lankan waters or from the Bay of Bengal. Further tracking efforts are recommended where the turtles are tagged early in the nesting season to understand their inter-rookery movements and find nesting frequencies per season. More tracking efforts from Maharashtra and elsewhere along the West coast of India are suggested to be taken up. This will help understand how the turtles from different nesting areas move and forage. Moreover, this will help identify the overlap between fishing zones and critical breeding and foraging areas along the West Coast to better manage and conserve the species through appropriate interventions.