Theses and Dissertations
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Item Assessing Ghost crab distribution, abundance and habitat use along the Coromandel Coast, Tamil Nadu(Wildlife Institute of India, Dehradun, 2025) Keerthi V; Gopi, G.V.Sandy beach ecosystems around the world are facing numerous threats and tremendous pressure due to ever increasing human population. One such threat, relevant to the Indian coastline, is the large scale plantations of shelterbelts of the exotic pine, Casuarina equisetifolia, which alters beach geomorphology. The effects of such plantations on permanent shore-dwelling organisms are poorly studied. Hence Ocypode crabs, the most conspicuous macro-invertebrate on sandy beaches, has been used as a model taxon to study the effects of different kinds of inland vegetation (Casuarina plantations, Mangrove plantations, native dune vegetation) on beach geomorphology and consequently, shore dwelling ghost crabs. The present study aims to - (1) Assess the density, distribution and demography of ghost crabs across treatments (2) Understand variations in habitat use and burrow architecture across treatments (3) Understand the effects of inland vegetation on beach geomorphology 2. A total of 24 transects, temporally replicated thrice each month between January 2025 - April 2025, were walked to estimate densities of ghost crabs using burrow counts as a proxy. 87 burrows across the treatments were cast using a mixture of Plaster of Paris and water and traits such as depth, diameter, shape and branching patterns were studied. Coast characteristics like slope, compactness, beach width, moisture and temperature were recorded at each study site. 3. Mean burrow densities and across shore distribution of Ocypode ceratophthalmus differed across the treatment types, with lowest densities in beaches adjacent to Casuarina plantations. This however wasn't statistically significant. The burrow structures also differed in complexity across treatments with the major drivers for this 7 difference being the size of the crab and the type of inland vegetation. Environmental variables were not found to have significant effects on burrow architecture. 4. The results indicate that the type of inland vegetation affects the population of ghost crabs through changes in beach geomorphology. Ghost crabs were also found to modify the structure of their burrows with changes in the habitat quality and environmental conditions, which gives insights into their adaptive capacities. The study, thus raises questions on the effects of certain management interventions, like the planting of shelterbelts on habitat quality and on the ecology of the species dwelling in the said habitats.Item Estimating Abundance, Habitat Use, and Acoustic Characteristics of Irrawaddy Dolphins (Orcaella brevirostris) in Chilika Lagoon(Wildlife Institute of India, Dehradun, 2025) Sakshi; Kolipakam, Vishnupriya; Gopi, G.V.This study provides a comprehensive assessment of the Endangered Irrawaddy dolphin (Orcaella brevirostris) in Chilika Lagoon, India, through an integrated approach combining visual and acoustic surveys, environmental modelling, and prey availability analysis. Visual line-transect surveys and passive acoustic monitoring (using FPODs) were used to estimate dolphin abundance and explore patterns of habitat use. Dive-time observations revealed that calves and non-calves differ in their diving behavior, with non-calves exhibiting longer and more variable dive durations. Mark-recapture analysis produced corrected abundance estimates ranging from 24 to 32 individuals, with variation influenced by observer mismatches and brief surfacing events. To assess prey availability, catch per unit effort (CPUE) surveys were conducted at 22 sites in collaboration with local fishers. The highest CPUE values were recorded in the high salinity area (Outer channel) and low salinity area (Northern sector), indicating these areas may offer better foraging opportunities. Prey community sampling across 11 sites revealed spatial differences in species richness and evenness, with some locations dominated by a few taxa and others exhibiting high diversity. Richness estimators suggested that the true species count exceeds what was observed, indicating under-sampling in certain areas. Environmental modelling using a negative binomial generalized linear model showed that salinity had a significant negative effect on dolphin acoustic detections, while dissolved oxygen and depth were positively associated but not statistically significant. The frequency ranged from 20 kHz to 200kHz with a median frequency of 98kHz. The interclick interval ranged from 850 millisecond to 1010865 milliseconds with a median of 23605 millisecond. The histogram for ICI displayed a positively skewed distribution, consistent with irregular click trains interspersed with longer pauses. The findings highlight the importance of salinity and prey availability in shaping dolphin distribution in Chilika Lagoon. The results support targeted conservation actions such as regulating freshwater inflow, protecting productive foraging zones, and expanding acoustic monitoring efforts to improve long-term management of this vulnerable population.Item Ecology of Golden jackal (Canis aureus) in Sariska Tiger Reserve, Rajasthan(Wildlife Institute of India, Dehradun, 2015) Chourasia, PoojaThis study aimed to examine the abundance and occupancy of jackal with the application of photographic captures using camera traps and diet composition through scat analysis, investigate species-habitat relationships from habitat features (non-spatial) and remotely sensed features (spatial) to understand how these variables govern occurrence pattern and predict the distribution of jackal in Sariska Tiger Reserve, Rajasthan. In India, jackal populations achieve high densities in pastoral areas such as Kutch, Maharashtra, Rajasthan, and Haryana. This study will vitally improve our state of knowledge to protect jackal and assist the development of theory on their social structure, behavior and habitat preferences in forested ecosystem. The study will help in suggesting localized monitoring mechanisms wherever necessary as this is important in minimizing surprise cases of extinction. The objectives of this study are as follows:-1. To determine the abundance of golden jackal. 2. To estimate the food availability, food habits and dietary niche overlap between golden jackal and other meso-carnivores.3. To evaluate the den site selection by golden jackal and, 4. To evaluate the habitat use by golden jackal. The study was conducted from 2010-2013 in Sariska Tiger Reserve (79° 17’ to 76°34’N and Latitude: 27° 5’ to 27° 33’ E), Rajasthan. Selected 160 km2 of intensive study area which was divided into four blocks. A total of 160 locations were selected for the placement of camera traps where, each block having 21 camera trap stations. Peafowl was observed to be the most abundant prey species throughout the study period. Amongst the wild prey species, nilgai was observed to be the most abundant wild ungulate prey species followed by, chital, wild pig and sambar in the study area..The Species distribution data was collected from camera trapping, direct sighting records, scat locations and track locations and was pooled for the entire study period 2010-2013, collectively making 413 observed point locations in the intensive study area.Item Abundance, distribution & pattern of human impact on river Dolphin (Platanista gangetica gangetica).(Wildlife Institute of India, Dehradun, 2018) Deori, Sunny; Qureshi, QamarThis study took place in a tributary of river Brahmaputra named Kulsi which originates from the Meghalaya enters Assam at Umkiam where it is known as Kulsi and finally discharges at Brahmaputra at Nagarbera, Assam. It is a highly populated riverscape. According to 2011 census data, the riverscape has 55972.88 hectares of cultivable land which is solely dependent for irrigation on natural sources (Rainfall and Rivers). Also, the river is divided into 7 River fishery under Revenue department of Assam. About 2500 commercial fishermen are registered under the fisheries of Kulsi River and 1,29,095 cultivators. Apart from this fine quality sand is a boon to the people of Kulsi floodplain. More than 5000 families were dependent on this business. The recent increase in construction business in Guwahati metropolitan and the nearby blooming towns is raising the earning bar of the people of Kulsi River. My study aimed at the following objectives: 1. Estimating the abundance & patterns of dolphin distribution across Kulsi River. 2. Estimating the effects of different human activities which can possibly affect the habitat and distribution pattern of dolphins in Kulsi River (special preferences to existing commercial fisheries, sand mining, & irrigation). 3. Socio- economic status of fishermen community, sand mining community and farmers and their attitudes towards dolphin and wider ecosystem conservation. 4. Examine suitable measures to minimize/prevent the harmfulness of these fishing gears and practices in the commercial fisheries of Kulsi.Item Patterns of Mammalian assemblages in forested riverscape in Koyna Wildlife Sanctuary, the Northern Western Ghats, India.(Wildlife Institute of India, Dehradun, 2021) Jelil, Shah Nawaz; Ramesh; Hayward, Matt W.This study deals with understanding mammal abundance and habitat status in an altered watershed, a dammed river that now forms a part of the Koyna Wildlife Sanctuary, in the northern Western Ghats, Maharashtra, India. Study aimed to understand habitat status and mammal abundance along the stream network within upstream Koyna Reservoir, 55 years after its construction. By doing this, I aimed to understand and draw conclusions on generally how reservoirs are functioning as protected areas. This study is particularly relevant and important for the threatened and unique landscapes of the Western Ghats. A systematic conservation prioritization analysis was conducted to assess which areas within Koyna should be prioritized for effective allocation of management resources. Overall, using robust modelling approaches, the thesis reports about the present status of riparian forests and mammals using these riparian areas in Koyna Wildlife Sanctuary.Item Seasonal Pattern in Habitat Selection by Birds of Jhimil Jheel Conservation Reserve Uttarakhand(Wildlife Institute of India, Dehradun, 2022) Das, Ankita; Ramesh, K.The present study was initiated to assess seasonal pattern in habitat selection by birds in Jhilmil Jheel Conservation Reserve (JJCR) which is a small-sized Protected Area (PA). This work also focuses on both ‘process’ and ‘pattern’ of bird community structure. The work also focusses on how small-sized PAs are equally important in conserving wildlife species such as birds. Understanding the relationship of birds with habitat provides insights into habitat use, which contributes in the conservation of species. Habitat selection of birds is one of the foremost steps to understand the complexity of their community. Some factors influencing habitat selection are habitat heterogeneity, structure and composition of vegetation, seasonality and co-occurrence. Habitat heterogeneity helps in maintaining high bird diversity. Abundance and distribution of species in a community also depends on the physiognomic, floristic composition of the forest vegetation and seasonality. For the present research work, the study area was stratified into six habitats: plantation, mixed deciduous forest (mixed forest), riverine habitat, scrub forest, grasslands and agriculture fields-human settlement.Item Evaluating methods to monitor tiger abundance and its prey in Indian Sunderbans(wildlife Institute of India, Dehradun, 2019) Roy, Manjari; Sankar, K.; Qureshi, QamarThis study conducted to test and evaluate different methods for estimating tiger and its prey population in Sundarban that can be adopted as part of a monitoring programme. For this study techniques were applied for the standard spatially explicit capture-recapture, tailored according to the local conditions to estimate tiger density in Sundarban for three years. Tiger densities were estimated at 4.08 (SE 1.51) in 2010, 5.81 (SE 1.24) in 2012 and 3.15 (SE 0.88) tigers/100 km2 in 2014. The tiger abundance for my camera trapped study area generated through conventional mark-recapture was 11 (SE 2), 24 (SE 3) and 16 (SE 3) tigers for 2010, 2012, 2014 respectively. Ungulates occupy a primary position in the diet of tigers and a monitoring protocol for tiger should inherently include a component of prey base estimation. Boat transect based distance sampling to generate density estimates for four years.Item Determinants of occurrence of snow leopard and its prey species in the Indian Greater and Trans Himalaya.(Wildlife Institute of India, Dehradun, 2017) Ghoshal, Abhishek; Pandav, Bivash; Bhatanagar, Yash veerUnderstanding patterns of species occurrences and how their distribution and abundance are affected by abiotic and biotic factors have been a major theme of ecological research. The range and changes in the distribution of a species are important parameters to assess conservation status. Robust assessment of factors affecting species distribution and abundance contribute to the identification of conservation issues, appropriate scale(s) for species conservation and key stakeholders. This study is attempted to understand how distribution and abundance of a large-ranging and difficult-to-sample carnivore and its primary wild-prey species are affected by topographic, vegetation and land-use variables, at wide and fine spatial scales. Study is focused on the snow leopard (Panthera uncia), the elusive, rare and endangered apex predator of the Central and South Asian mountain systems, and its main prey, blue sheep or bharal (Pseudois nayaur) and Asiatic ibex (Capra sibirica) for the work. I have utilized tools from quantitative ecology and social sciences through the thesis.Item Spatial pattern in the occupancy and abundance of red junglefowl (Gallus gallus) in western Shivalik landscape, India.(Wildlife Institute of India, Dehradun, 2015) Fernandes, Merwyn; Sathyakumar, S.; McGowan, PhillipThis study was to identify landscape-level patterns of distribution, abundance and habitat occupancy of G. gallus across different spatial and temporal scales in a forest landscape, to help guide strategies for Galliformes conservation management. The present study was undertaken in an area (29˚54’ to 30˚24N and 77˚32’ to 79˚12’ E) that is situated within the Shiwalik Hills of Northwestern India, in the districts of Dehradun and Haridwar in Uttarakhand State. G. gallus is listed as a ‘Least Concern’ species, making an assessment of their status requires reliable information on population size and distributions. The structural component of understorey was one of the most important factor that determined occupancy and detection probabilities for the species. The structural components are known to provide cover to G.gallus, and other gallinaceous species that nest on the forest floor. The main threat to G. gallus is hybridisation and hence there is an urgent need to assess ranging patterns, survivorship and other basic demographic parameters, population status, genetic variability and purity of G.gallus in areas adjoining PAs where most of these forests have multiple uses and domestic/feral fowls are in close proximity in order to keep the common species common.Item Ecology of sympatric small carnivores in Mudumalai Tiger Reserve, Tamil Nadu(Wildlife Institute of India, Dehradun, 2013) Kale, Riddhika; Sarkar, K.; Qureshi, QamarThis study aimed to examine the abundance and occupancy of small carnivores with the application of photographic captures using camera traps and diet composition of small carnivores through faecal analysis, investigate seasonal species-habitat relationships from microhabitat (non-spatial) and remotely sensed features (spatial) to understand how these variables govern their occurrence pattern and predict the distribution of small carnivores in Mudumalai Tiger Reserve, Western Ghats. The study was conducted from 2009-2011 in Mudumalai Tiger Reserve (11°32' 11°43'N; 76°22'-76°45'E), Western Ghats. This study will critically improve our state of knowledge to protect lesser carnivores and aid the development of theory on their social structure, behavior and habitat preferences.Study species include jungle cat (Felis chaus), leopard cat (Prionailurus bengalensis), rusty spotted cat (Prionailurus rubiginosus), common palm civet (Paradoxurus hermaphroditus), small Indian civet (Viverricula indica), brown palm civet (Paradoxurus jerdoni), grey mongoose (Herpestes erdwardsii), ruddy mongoose (Herpestes smithii) and stripe-necked mongoose (Herpestes vitticollis). The objectives of this study area as follows:- 1. To determine the abundance and occupancy of small carnivores in Mudumalai Tiger Reserve. 2. To study the dietary pattern of small carnivores. 3. To determine spatial and non-spatial variables governing the occupancy of small carnivores and 4. To predict the distribution pattern of small carnivores through habitat suitability modeling in Mudumalai Tiger Reserve.