Theses and Dissertations
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Item Spatial abundance of ungulates and role of predation on chital (Axis axis) demography and behaviour in Corbett Tiger Reserve, Uttarakhand, India.(Wildlife Institute of India, Dehradun, 2022) Banerjee, Sudip; Jhala, Y.V.; Qureshi, QamarTo address the first objective which was to estimate the abundance of ungulates in different habitats of CTR, I have used line transect-based distance sampling approach to estimate the density of four major ungulate species (chital, sambar deer, barking deer, and wild pig) of CTR in ~520 sq. km of the Corbett National Park (CNP) region. Density was estimated using 156 spatial transects replicated 1 to 4 times over four sampling years. Both year-wise and pooled (weighted average of four years) density estimates were highest for chital followed by sambar. Barking deer had the lowest density. Chital density has remained stable over the years. Post-stratifying the densities of the four ungulates by three major habitat types of CNP (grassland, saldominated, and mixed deciduous) exhibited the highest density of chital in the grassland and lowest in the sal-dominated forest. Sambar density on the other hand was highest in the mixed deciduous and lowest in the grassland. Barking deer also exhibited a similar trend of habitat-wise density. A significant part of my thesis was focused on the objective of evaluating the precision and cost-effectiveness of three different density estimation techniques. The diverse ungulate assemblage and complex terrain of CNP provided an excellent environment to conduct this experiment.Item Conservation and management of snow leopard and co-predators with special reference to large carnivore-human conflicts in select areas of western Himalaya.(Wildlife Institute of India, Dehradun, 2016) Maheshwari, Aishwarya; Sathyakumar, S.The study aims to investigate occurrence, distribution of snow leopard, co-predators and their prey in Kargil, and some gaps areas in Greater Himalayan region of Himachal Pradesh and in Greater Himalayan and Trans Himalayan regions in Uttarakhand. Objectives are as follows: Considering gaps in the knowledge on snow leopard in the Western Himalaya, this study focused on the following objectives 1. Determine conservation status and distribution of snow leopard and copredators in Kargil, Uttarakhand and Himachal Pradesh 2. To assess occurrence and estimate density of prey species in Kargil 3. To asses food habits of snow leopard in Kargil, Uttarakhand and Himachal Pradesh 4. To assess snow leopard-human conflicts in Kargil, Uttarakhand and Himachal Pradesh 5. To Predict habitat suitability of snow leopards in the western Himalaya.Item Occupancy and abundance of tigers and their prey in Terai Arc Landscape, Nepal.(Wildlife Institute of India, Dehradun, 2012) Karki, Jhamak Badur; Jhala, Y.V.; Pandav, BivashThe occupancy, distribution and tiger density are important information for management and conservation policy formulation. Realizing this need, this study was undertaken. The major wild prey species of tiger are spotted deer (Axis axis), wild pig (Sus scrofa), sambar (Rucervus unicolor), swamp deer (Rucervus duvaucelli duvaucelli), barking deer (Muntiacus muntjak), hog deer (Heylaphus porcinus) and gaur (Bos gaurus) in Nepal. To evaluate the occupancy of tiger in Nepal's Terai Arc landscape (TAL), sign survey was conducted in 96 grids (area 225 Km2 ) in 14 districts, including PAs. To assess correlation of the tiger occupancy with the availability of wild prey, and the human disturbance with the habitat use by the tiger, the sign of human disturbances (fire, timber cut, fuel wood collection, sign of poaching) and prey presence were recorded during the winter season. To estimate the density of tigers wild prey in PAs of Nepal's TAL, distance sampling was conducted along the predefined line transects during the summer seasonItem The ecology and conservation of ungulates in Great Himalayan National Park, Western Himalaya.(Wildlife Institute of India, Dehradun, 1999) Vinod, T.R.; Rawat, G.S.Ungulates form a major component of the mammalian fauna in the Himalaya. In total, 19 ungulate species belonging to four families viz., Moschidae, Cervidae, Bovidae and Equidae, inhabit the Himalaya, out of which eight species are reported from the state of Himachal Pradesh (HP). Apart from some surveys and short term ecological studies on a few ungulate species of Western Himalaya, there has been no detailed study on ungulates of HP except for Himalayan ibex (Capra ibex sibirica). The available literature highlights the difficulties of studying rare and/ or elusive ungulates in Himalayan condition. Long term study on the ecology of theses' species are needed for the conservation and monitoring. Present study on the ecology and conservation of ungulates namely goral (Nemorhaedus qoral), Himalayan musk deer (Moschus chrvsogaster), Himalayan tahr (Hemitragus jemlahicus), in Great Himalayan National Park, Kullu district, HP, was conducted from January 1996 to November 1998. An intensive study area of ca. 90 km2 was selected in the South-western region of. the Park, which represents various ecological zones of the Park. The objectives of the study were (i) to estimate the abundance and density of goral, Himalayan musk deer & Himalayan tahr in relation to human use, (ii) to determine the group size. composition & sex ratio of these animals. (iii) to study the habitat use pattern and (iv) to identify and discuss conservation issues. mitigation measures and to develop a long term' monitoring programme. In this study an attemp has been made to estimate the abundance and density of major ungulates viz, goral, Himalayan musk deer and Himalayan tahrItem Habitat Ecology of major ungulates in Kedarnath musk deer sanctuary, Western Himalaya.(Wildlife Institute of India, Dehradun, 1994) Sathyakumar, S.; Johnsingh, A.J.T.Present study on the habitat ecology of major ungulates in Kedarnath Wildlife Sanctuary "(WS) was conducted from March 1989 to November 1991. The objectives of this study were to de,!elop suitable techniques for estimating ungulate abundance and density; to study their habitat utilization pattems; and to assess the status of ungulates and their habitats in different parts of the Kedarnath WS.Item Spatial Dynamics and Drivers of Nearshore Aggregations in Olive ridley Sea Turtles along the Gahirmatha Coast by(Wildlife Institute of India, Dehradun, 2024) Sarkar, Arnab Dey; Prabakaran, Nehru; Kumar, R.S.; Pandav, BivashOlive ridley sea turtles (Lepidochelys olivacea) exhibit a well-documented phenomenon known as nearshore aggregation during their breeding season. These aggregations, comprising large numbers of turtles in shallow coastal waters, are a common feature observed along most of the mass nesting beaches. The ecological benefits of such aggregations are multifaceted, potentially including enhanced predator avoidance and increased opportunities for mate encounter. The importance of studying these nearshore aggregations stems from their vulnerability during this period. Olive ridley turtles within these aggregations are susceptible to various threats, including bycatch mortality from fishing gear. Understanding the spatial and temporal dynamics of these aggregations is crucial for developing effective conservation strategies. The Gahirmatha nesting site presents a unique case due to the influence of the Brahmani-Baitarani River system. The substantial freshwater inflow and sediment discharge from this river system have resulted in a vast area of shallow seabed compared to other nesting grounds. This distinct ecological setting necessitates a dedicated investigation into the dynamics and influencing factors of nearshore aggregations specific to Gahirmatha. The study examined the distribution and density of olive ridley sea turtles near Gahirmatha, India, a critical nesting site, with a particular focus on how environmental factors influence the location of these nearshore aggregations. Surveys were conducted throughout the breeding season, recording turtle sightings and environmental data. The findings reveal that olive ridley turtles are not distributed randomly in the nearshore waters. Instead, they form concentrated aggregations in shallow depths (less than 5 km offshore and 5-15 meters deep) before nesting. The location and density of these aggregations were not static but shifted throughout the breeding season. During the pre-nesting season, turtles were more dispersed across a wider area. As the season progressed and nesting approached, the aggregation grew denser and shifted closer to the nesting beach. The study also identified distance from the coastline and the nesting beach as the key factors influencing the distribution of these nearshore aggregations. Additionally, the unique shallow seabed near Gahirmatha, created by the discharge from the Brahmani-Baitarani River, might influence the preferred depth range of turtles compared to other nesting sites. Understanding these dynamic aggregation patterns is crucial for effective conservation efforts. Protecting these areas is essential for the well-being of this globally significant olive ridley population. However, it's important to acknowledge that the exact locations of these aggregations can vary between years. This year's lower nesting numbers suggest fewer turtles arrived in the nearshore waters, potentially impacting the size and distribution of the observed aggregations. This study emphasizes the need for long-term studies to gain a more comprehensive understanding of these variations and the factors influencing them. The study suggests a targeted approach of focusing on areas with high turtle usage. By implementing stricter patrolling measures within these zones, the forest department can significantly reduce threats like bycatch mortality from fishing activities. This targeted approach would be more effective in safeguarding the turtles compared to focusing on reducing illegal fishing in the entire sanctuary, considering the limited resources available.Item Density Distribution and Factors Influencing Sea Stars in Selected Islands of Lakshadweep India(Wildlife Institute of India, Dehradun, 2013) Jayaram, Sharmila; Hussain, S.A.; Gopi, G.V.; Apte, DeepakCoral reefs are the most fragile, complex and diverse ecosystem on earth. But recently, they arc under severe threat due to both natural (climate change, storms and disease outbreaks) and anthropogenic factors (overexploitation, coastal developmental activities and pollution). As evident from earlier studies, a major factor causing degradation of coral reefs is due to an asteroid species belonging to phylum Echinodermata which is considered second to storm damage. Thus to analyze the condition in Lakshadweep Islands I assessed the density of asteroids in four Islands of Lakshadweep. It was found that the five species detected belonging to three families (Oreasteridae, Linckiidae and Acanthasteridae) were having varied density across the four islands. Overall density estimates of the asteroids ranged from 0.05(S.E = 0.02) to 0.80(S.E = 0.09) per 250 square meter. The asteroid density was highest in the uninhabited Island named Bangaram. Correspondence Analysis (CCA) showed that major gradients in environmental variables influenced asteroid species distribution. Sample scores on ordination ' axis 1 were strongly correlated with water pH, water depth and dead coral. Out of the three strongly correlated environmental variables pH was found to be the most ecologically important variable that affects the asteroid distribution. Corallivorous asteroid population outbreaks are becoming a boon to the coral reef ecosystem all over the world and contribution of water pH variation of this outbreaks are being studied well. Thus management strategies in Lakshadweep Islands that 'accounts the variation of water pH are required to conserve the coral reef ecosystem.Item Age Estimation of a Breeding Population of Olive Ridley Sea Turtle (Lepidochelys olivacea) Along the Odisha Coast, Eastern India: Using skeletochronology(Wildlife Institute of India, Dehradun, 2013) Baburam, Anupya D.; Pandav, Bivash; Kumar, R.S.A migratory population of olive ridley sea turtle (Lepidochelys olivacea) forms huge reproductive congregations in the coastal waters of Odisha every winter. This breeding population of olive ridley has been subjected to heavy fisheries related mortality for the past two and half decades. Although a number of studies have been carried out on olive ridleys congregating and nesting along the Odisha coast, the impact of such large scale mortality on the demography of this breeding population has been least understood. The effect of this continued mortality on the age class of olive ridleys nesting along Odisha coast is not known. In order to understand the age class of this breeding population I carried out this study from December 2012 till May 2013. I used skeletochronological analysis to estimate the age class of this breeding olive ridley sea turtle population. Although this technique has been applied for marine turtles mostly in North Pacific, Atlantic and Gulf of Mexico coast of United States of America, no studies of this kind have been carried out on sea turtles of Eastern Pacific as well as Indian Ocean region. This study provides the information needed to bridge this gap and establish baseline for future skeletochronological studies on the breeding population of olive ridley. Humeral samples from 85 dead turtles (29 males and 56 females) washed ashore the Odisha coast was collected for skeletochronological studies. Cross sections were taken from the mid-diaphysis, just distal to the deltopectoral crest and beneath the insertion scar on the humerus were taken using first a Dremel 4000 round saw, then a freezing stage microtome. These sections were processed according to standardized histological techniques; growth rings on the stained humeral cross sections were counted to estimate age of dead turtles. Two age estimation protocols were used; the correction factor protocol and the ranking protocol; which yielded age estimates of 19.9 - 51.8 and 24 – 49 years respectively; for a size class of 56 - 74 cm (SCL). No correlation between size class and age was obtained from this analysis. This relationship was not established because the samples collected were from an adult breeding population, whereas, in the previous studies, sample collection represented individuals that greatly varied in size (hatchlings to adult). This study suggests that adult breeding population size class has no correlation with age; however, age can be correlated with size class of a younger population. This breeding population is sustaining a wide age group even though mortality rates are high in this areaItem Abundance, Habitat Relationships and Behavior of the Semi-Fossorial Indian Desert Jird, Meriones hurriancae, in Kachchh, Gujarat(Wildlife Institute of India, Dehradun, 2011) Ramesh, Divya; Jhala, Y.V.; Qureshi, QamarPopulation sizes, habitat relationships and behaviour are among basic ecological aspects pivotal to demystifying a species and its place in the ecosystem. Numerous in species and number, desert rodents offer immense scope for such investigations. The Indian desert jird, Meriones hurrianae, though common, is remarkably little known. This study, conducted in Kachchh, Gujarat, estimates population sizes, examines factors in the habitat likely to influence their occurrence, and elucidates the activity pattern and time budget across 2 land use types, agricultural and natural areas, during winter (December February) and summer (March-May). Animals were caught in 9 colonies using Sherman traps and population estimated under closed population Capture-Mark-Recapture framework in Program MARK, using individual covariates (age class, gender, body weight, site). Colony parameters (length, width, number of holes) were regressed against known Mark-Recapture (MR) population estimates to develop predictive models for estimating population size from indices. Population sizes varied from 2 to 10 individuals. Number of holes in a colony provided robust estimates of the number of individuals in that colony (N=16, R2=0.96, t=18.19, pItem Evaluating Tiger (Panthera tigris) Population Estimation Approches in a High Density Area in Kanha Tiger Reserve(Wildlife Institute of India, Dehradun, 2005) Sharma, Rishi Kumar; Jhala, Y.V.Reliable estimates of status and population trends are critical for the conservation of large terrestrial carnivores as they play an important role in evaluating effectiveness of conservation efforts and also provide benchmark data for future management decisions. Camera trapping technique have been widely used for population estimation of cryptic carnivores including tigers, but the issues regarding sampling design and effort required to effectively sample an area have been paid less attention. An attempt was made to deal with these issues in the present study. The use of intensive search effort for tiger density estimation was also evaluated. Over a 30- day survey period, 33 camera trap sites were sampled in Kanha meadows of the Kanha Tiger Reserve. A total sampling effort of 330 trap nights yielded 39 photocaptures of 12 individual tigers over 10 sampling occasions that effectively covered a 111-km2 area. The model M(o) fitted the capture history data well. The estimated capture probability/sample, p-hat = 0.22, resulted in an estimated population size and standard error (N(SE TV)) of 13 (1.19), and a density (D(SE Z))) of 11.71 (1.74)7100 km2. Camera spacing was found to considerably influence the population estimation. An increase in camera spacing from 1.5 to 2.5 km resulted in a loss of 35% (n=7) of photo captures which consequently decreased the precision of the estimates, though accuracy was not affected. A reduction in the trapping effort in terms of reduced trap nights resulted in lower level of precision though the accuracy of estimates was not affected. Increase in the camera spacing from 1 to 2 km with a decrease in the number of sampling occasions (six) resulted in the loss of 42% of photo captures (n=12) and loss of 25% of individual tigers (Mz+/=9) thus underestimating the true tiger population by 16% ((N(SE N)) being 10(1.84) The data also suggests that the photo-captures are not likely to generate abundance index for species other than tigers, since the cameras are placed to maximize tiger captures in space and time. My results suggest that a thorough reconnaissance survey is of utmost importance for camera trapping studies as it can help to maximize the capture probability of tigers and circumvent the sampling problems. The different statistical estimator’s viz. capture-recapture, jackknife and bootstrap did not show significant differences in the population estimation. Bootstrap estimator performed better than jackknife in terms of greater precision. The differences between the density estimates generated by “camera trapping” (D=l 1.71/100 km2, S.E.=1.74) and “intensive search effort” (0=12.74/100 km2, S.E.=2.27) for tigers were not significantly different. Our results suggest that “intensive search effort” for tigers if used within capture-recapture framework can be used to arrive at reliable population estimation