Theses and Dissertations
Permanent URI for this communityhttp://192.168.202.180:4000/handle/123456789/1
Browse
11 results
Search Results
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 Habitat Utilisation of Asian Water Monitor (Varanus salvator) in and Around Bhitarkanika National Park, Odisha(Wildlife Institute of India, Dehradun, 2025) Rayen, W. Michael Isaac V.; Pandav, Bivash; Das, AbhijitThe water monitor lizard Varanus salvator is the largest of all lizards in India, and its distribution is restricted to certain pockets of the northeast, eastern coast and Andaman and Nicobar Islands. Despite being the largest lizard, only limited studies have been done on this species, especially on the movement pattern and home range. This study focuses on the space use pattern of Varanus salvator in the mangrove habitats of Bhitarkanika National Park, Odisha. In total, five individuals were radio-tagged with VHF transmitters in the form of a backpack. All the tagged individuals were located twice in a day, and the location(coordinates), activity and other habitat variables were recorded. The data collected were analysed for their movement pattern, activity range and overlap between individuals and the human-dominated landscape was estimated using KDE. Along with the space use environmental variables (Ambient temperature, Relative humidity, vegetation species, canopy openness, etc) were analysed individually with behaviour to the relation between them using Fisher’s test. The results from this study add more information about its activity range, movement pattern and behavioural aspects in the mangrove landscape of India, which can be useful in the rescue, rehabilitation and management of the species.Item Habitat Characterization and Spatial Distribution of Quercus lanata Sm. in the Kumaon Himalaya(Wildlife Institute of India, Dehradun, 2025) Kaushik, Shikhar; Kumar, Amit; Rawat, G.S.Oaks are climax species which evolved around 56 million years ago. India is home to around 35 species of oaks out of which only 5 species are native to Uttarakhand. In Western Himalaya 3 species make extensive continuous forests which includes Banj oak forest, Moru oak forest and Kharsu oak forest. They show gregarious nature and provide countless ecological and economic benefits to the country. The other two species, Quercus glauca and Quercus lanata are patchy is distribution. For Quercus lanata the Kumaon Himalaya is the western most limit and therefore that species is patchy and shows disjunct population. This study aimed to understand the population, regeneration, habitat characterisation and distribution of Quercus lanata in Kumaon. Descriptive analysis was used to understand the population structure and associate species and maxent modelling was used to develop habitat suitability model. The overall population of Quercus lanata (Rianj) in Kumaon shows a stable and gradually growing trend. Quercus lanata shows a diverse preference to habitat which ranges from northerns moist slopes to drier southern slopes. The significant values from analysed data suggest that its preference at southern slope is comparatively higher. It occurs with Quercus leucotrichophora as well as with Pinus roxburghii. The major co-occurring species with Quercus lanata are Rhododendron arboreum and Myrica esculenta. The developed habitat suitability and generalised linear models helped to understand that elevation and aspect play a significant role in distribution of Quercus lanata. The demand of Quercus lanata for fodder and fuelwood in village area is quite high and therefore requires sustainable practices. As of now Quercus lanata is classified under either Banj oak forest or Moru oak forest which reduces the level of conservation and management this species require.Item Movement and space use pattern of Tigers in the Eastern Vidarbha landscape, Maharashtra, India(Wildlife Institute of India, Dehradun, 2024) Hussain, Zehidul; Habib, BilalMovement is a crucial ecological process that influences the survival, population dynamics, and evolution of animals. Animal movement patterns are diverse and are influenced by life stages, sex, age, and habitat requirements. The relationship between animal movement and conservation is complex, particularly due to human-induced environmental changes This study emphasises that various factors influence animal movement, including individual characteristics and external factors such as resource availability, distribution, competition, and predation. Animals adjust their space use based on seasonal changes in resource availability. Additionally, movement patterns and space use can be influenced by habitat disruption, forcing individuals to displace and establish new home ranges. Landscape features play a significant role in animal home ranges, with resource distribution determining the extent of the required area. Fragmentation of habitats and human activities can affect landscape connectivity, leading to isolation, reduced gene flow, and potential genetic bottlenecks or local extinctions. Thus, maintaining habitat connectivity is crucial for long-term survival of highly mobile species. The study highlights the need for comprehensive datasets and technological advancements, such as GPS tracking, to study animal movement and behaviour. It also emphasises the importance of studying dispersal patterns, as dispersed individuals often encounter humandominated landscapes and face increased vulnerability to anthropogenic effects. This study focused on quantifying movement patterns and space use across three life stages: predispersal, dispersal, and post-dispersal phases. The results revealed differences in space use within and outside protected areas, with individuals outside protected areas requiring larger territories. The study also identified seasonal variations in space use and movement patterns, with dispersed tigers exhibiting the highest space use. Land-use composition, landscape configuration, and anthropogenic disturbances influence the use of tiger space. These findings provide insights into the factors influencing tiger movement and space use in a human-dominated landscape. They highlighted the importance of maintaining habitat connectivity, reducing anthropogenic disturbances, and restoring suitable habitats outside protected areas to facilitate dispersal and ensure the long-term survival of tigers.Item DIVERSITY AND DISTRIBUTION OF BIRDS IN BHARATHAPUZHA RIVER BASIN, KERALA(SACON, 2024) P N , Anoop Raj; Kumara, H NBharathapuzha also known as the Nila River is the second-longest river in Kerala. It is considered as one of the most important rivers in Kerala for its ecological, cultural, and historical importance. Thus, it is known as the cradle of civilisation in Kerala. This river originates from the northern and southern rims of the Palakkad Gap. It flows towards the west through the Coimbatore district in Tamil Nadu and the Palakkad, Thrissur, and Malappuram, districts of Kerala before draining into the Arabian Sea. The river's total length is 209 km with a drainage area of 6186 km2. Chitturpuzha, Kalpathipuzha Gayathripuzha, and Thoothapuzha are major tributaries of this river. Birds are considered as indicators of habitat quality. They play an important role as predators, prey, pollinators and scavengers in nature. Understanding the natural bird assemblage, its patterns, and its process will help prioritize the potential conservation areas. Many researchers have attempted to study bird communities in the different habitats in the Western Ghats. Their observations on birds provided useful information to understand the distribution trend of birds. Most of such studies focused on the forest ecosystems in the protected area network. Understanding the distribution pattern of birds and their drivers in highly disturbed ecosystems outside the protected area network is less attempted. From the origin to the mouth, the river passes through various ecosystems and topographic conditions. Bharathapuzha originates and runs through forest ecosystems in the Western Ghats hill ranges initially, then travels through various human habitations, and agrarian lands and finally reaches the Arabian Sea. So, it supports bird communities of different forest ecosystems, agrarian lands, water bodies, and human habitations including the urban areas. Most of these ecosystems are located outside the protected area network and are vulnerable to anthropogenic pressures. Deforestation in the hill region, construction of check dams, indiscriminate sand mining, the spread of weeds and invasive plants inside the river channel, expansion of monoculture plantations, encroachment and water pollution are the major threats to the river ecosystem. This study attempted to understand the patterns of avifaunal assemblage in the Bharathapuzha river basin which is highly disturbed due to anthropogenic pressures that destroyed the riverine habitats, water quality, and natural water flow.Item Foraging ecology of Great-Slaty Woodpecker in and around Pawalgarh Conservation reserve in Western Himalaya(Wildlife Institute of India, Dehradun, 2024) Kaur, Sarabjeet; Gopi, G.V.; Uniyal, V.P.The Great Slaty Woodpecker (Mulleripicus pulverulentus, Temminck 1826) is an old-world woodpecker that prefers mature and old-growth dipterocarp forests (including Shorea robusta, Sal) across its known distribution range. The study reveals population demography, the social system and foraging behavior from logged forest and infer the distribution and home range of the Great Slaty Woodpecker, a cooperative breeding bird species, in and around the Pawalgarh Conservation Reserve in the western Himalaya of Uttarakhand state. This study presents the first census conducted for the Great Slaty Woodpecker, providing an ecological baseline for the species population estimation from its known distribution range. I inferred the home range size of each group based on 161 independent sightings of 11 family groups. These sightings represent behaviors such as foraging, nesting, roosting, vocalizations, and territory defenseItem Land, lion and locals: Understanding the distribution of lions and large carnivore human interactions in the Greater Gir Landscape of Saurashtra(Wildlife Institute of India, Dehradun, 2025) Gogoi, Keshab; Jhala, Y.V.Apart from the Gir Protected Areas, Asiatic lions inhabit various coastal forest patches in Mangrol, Veraval, Kodinar, Mahua, and Rajula-Jafrabad areas. They also reside in Girnar Wildlife Sanctuary (WLS) and within human-dominated landscapes across Amreli, Junagadh, and Bhavnagar districts (Mitiyala WLS), as well as along the Shetrunji river, Hipavadli, Palitana, and Shihor. However, the presence of extensive townships, linear infrastructure, and urban development has led to the fragmentation of lion populations. This fragmentation restricts the efficient exchange of individuals across the matrix of multi-use human-dominated landscapes. Historical corridors that once connected hills, forests, and lion habitats, including protected and un-classed forests, have largely succumbed to agriculture and human settlements. To address this pressing issue, it is crucial to identify and conserve existing habitat corridors that connect these lion patches. Failure to do so could exacerbate repropuctive isolation, leading to genetic bottlenecks and reduced genetic diversity within lion populations. To tackle this challenge effectively, I utilized Circuitscape theory to model connectivity among habitat patches in the Saurashtra landscape at a scale of 1km². Additionally, I employed least-cost pathway tools to determine the shortest pathways with the least total costs. My analysis revealed varying levels of permeability among different lion habitats. For instance, the permeability between the coastal forests of Veraval-Sutrapada and Rajula with Gir PA was found to be high. Similarly, coastal patches around Mahua taluka exhibited high permeability with forest patches around Palitana. However, the permeability between Girnar and Gir Forest was moderate, indicating the need for interventions to maintain suitable lion movement. In the eastern part of the Gir protected area, there is notable connectivity between Mitiyala Wildlife Sanctuary and Gir, as well as other habitat patches along the Shetrunjay river. By prioritizing the identification and conservation of these critical habitat corridors, we can enhance connectivity among lion populations, mitigate the risk of genetic isolation, and safeguard the long-term survival of Asiatic lions in the Saurashtra landscapeItem Landscape-level assessment of select group of pollinators and factors influencing their diversity and distribution in Kullu Valley, Himachal Pradesh.(Wildlife Institute of India, Dehradun, 2024) Khan, Sushmita; Uniyal, V.P.; Ramesh, K.Change detection analysis using satellite data in a remote sensing platform is a crucial tool for understanding shifts in land use and land cover (LULC) over time, allowing for the identification of environmental and human-induced changes across various spatial and temporal scales. This method aids in assessing the impact of factors like urban expansion, agricultural practices, deforestation, and climate change on biodiversity and ecosystems. Climate change, particularly in vulnerable regions like the Himalayas, poses significant threats to ecosystem services and biodiversity. This study explores the impact of LULC and climate change on pollinator diversity and distributional patterns in the Kullu and Tirthan valleys of Himachal Pradesh. By compiling a comprehensive list of entomofauna pollinators across various orchards in different landscape configurations, the research aims to emphasize the need of conserving pollinator species in this ecologically sensitive region. Additionally, the study predicts potential shifts in pollinator distribution under future climate scenarios, providing valuable insights for conservation strategies. Through systematic analysis, the research contributes to a deeper understanding of pollinator communities and their interactions within the mountain horticultural belt of the Indian Himalayan Region. Ultimately, the findings aim to inform targeted conservation efforts to preserve the rich biodiversity of pollinators in this area. The research focuses on two major valleys within the Kullu district, each presenting contrasting landscapes and ecological contexts. The Kullu valley, a 76 kms long stretch situated along the Beas river, is characterized by diverse land use patterns and heightened anthropogenic activity, particularly in horticulture and tourism. In contrast, the Tirthan valley, nestled along the Tirthan river for a 45 kms long stretch, is designated as a conservation area with minimal disturbance and dense forest cover. The study meticulously investigated pollinator diversity dynamics in the Kullu and Tirthan valleys. The study conducted in the Kullu Valley aimed to analyze land use changes over time using Landsat satellite imagery from 2000 and 2022. High-quality images with minimal cloud cover were obtained for both years, ensuring accurate analysis With the aforesaid aim in focus, I have tried to address the following three objectives in my thesis: Objective 1: To assess the change in landscape composition of the study area over time.• Objective 2: To assess the effect of change in landscape configuration and horticultural practices on pollinator communities (diversity and abundance) and their services. • Objective 3: To model the distribution of major pollinators of economic importance belonging to different groups (Hymenoptera, Lepidoptera, Coleoptera, Diptera) in the study area.Item Golden Langur Distribution, Habitat Selection and Corridor – Connectivity: Assessing Patterns and Addressing Threats(Wildlife Institute of India, Dehradun, 2024) Basumatary, Rishi; Nath, Anukul; Gopi, G.V.; Chetry, DilipThe Golden Langur (Trachypithecus geei), is an endangered colobine primate, confined to fragmented forest patches in western Assam, India, and south-central Bhutan. The golden langur has experienced severe habitat loss and fragmentation due to ethnolinguistic and religious conflicts between the late 1980s and late 1990s, followed by developmental activities in western Assam. The primary threat faced by the golden langur in India are the rapid reduction of its natural environment and the fragmentation of its habitat. Factors such as a limited population size, the breakdown of meta-population dynamics, and unique traits of a species often make a population in a fragment more likely to experience local extinction. Due to the significant decline in the range of Golden langur in both Bhutan and India, as well as the ongoing destruction of their habitat in India, it is imperative to safeguard even the smallest local populations. The populations residing in these fragmented Reserved Forests and Proposed Reserved Forests are effectively confined, separated from the primary breeding population, and susceptible to demographic and genetic influences. The objective of this study is to understand the current distribution, suitable habitat, and connectivity of corridors for the severely fragmented southern population of golden langur in India. Additionally, the study aims to examine the specific habitat preferences and demographic patterns of langur groups, as well as evaluate the threats that this fragmented population faces. The study was carried out in nine fragmented forest patches that includes Wildlife Sanctuary (WLS), Community managed RF (CMRF) Reserved Forest (RFs), and Private Rubber Plantations and Adjoining Forests (PRP_AF). In the present study, a total of 123 trails, ranging from 0.4 km to 1.6 km, were walked, covering a total distance of 118.72 kilometers. During these surveys, a total 51 troops (including 8 multi-male multi-female troops and 5 all-male groups), consisting of 499 individuals were encountered. The mean group size and age-sex ratio between different protected regimes that include wildlife sanctuary (WLS), community managed RF (CMRF), reserved forest (RF) and private rubber plantation and adjoining forests (PRP_AF) were compared. The overall mean group size of the langur was 9.78 (± 0.69 SE). Of the total 499 individuals, 13.22 % comprised of adult males, 41.88 % adult females, 16.83 % sub-adults, 10.02 % was juveniles and 18.03 % was infant. The average age-sex ratio of adult males to adult females was 0.287 (± 0.04 SE), juveniles to adult females was 0.224 (± 0.02 SE) and infants to adult females was 0.407 (± 0.04 SE). The infant to female ratio was found higher in wildlife sanctuary as compared to other reserved forests in the study area. The current study revealed that approximately 883 km² of the area is highly suitable for the endangered golden langur. Percent forest cover was found to be the most important variable in determining the probability of occurrence of golden langur in India. The corridor connectivity analysis showed high conductance for corridors namely Bamungaon and Khoragaon RF. Similarly, the connectivity is permeable between Kakoijana and Bamungaon. Other corridors identified in the study are Bhumeshwar Hill, Nakati RF and Kakoijana RF. On the other hand, there is high conductance among corridors of Chakrashila WLS and Nadangiri RF. Additionally, fine scale habitat selection study showed that tree species diversity, canopy cover and food plant density are the key in determining the occurrence of golden langur. In the last six years, a total of 56 mortality and injury incidents were reported from the study area which include 45 deaths and 11 injuries. Electrocution accounted for 29 cases, especially near forest edges, while 21 road accidents occurred mainly on national and state highways, as these roads are broader and have higher traffic volumes compared to village and town roads. Most accidents happened in the corridors between Chakrashila WLS-Nadangiri RF and Kakoijona RF-Bamungaon RF. Specific measures need to be taken to minimize electrocutions and road accidents of golden langur in the region. Mitigation measures like insulating electric lines and road safety protocols such artificial canopy bridges (ACB) and metal animal overpasses (MAOP) are essential for safe and easy movement along these corridors for the golden langur's survival in fragmented habitatsItem RISK ASSESSMENT OF POTENTIALLY TOXIC ELEMENTS IN THE HABITAT, AND DIET OF SMOOTH-COATED OTTER (Lutrogale perspicillata) IN TUNGABHADRA OTTER CONSERVATION RESERVE (TOCR), KARNATAKA(Wildlife Institute of India, Dehradun, 2024) Ahmed K., Niyaz; Johnson, J.A.; Hussain, S.A.; Sah, RuchikaSmooth-coated otter (Lutrogale perspicillata), is a vital indicator species for freshwater ecosystems, playing a crucial role in maintaining ecological balance. Despite their essential place in the food web, they are always neglected compared to other terrestrial carnivores. This study explores the distribution, diet, and, ecotoxicological exposures to smooth-coated otters in Tungabhadra Otter Conservation Reserve, Karnataka. The study area, encompassing a 36km stretch of the Tungabhadra River (TOCR), is a unique habitat facing significant anthropogenic pressures, including mining activities and pollution, which threaten the local biodiversity and otter populations. The distribution of smooth-coated otters in TOCR was assessed through intensive sign surveys, revealing a clumped distribution pattern. Otter signs, including spraints, pugmarks, and grooming sites were dominant signs found in the landscape. Dietary analysis was examined by analysing the spraints (scat), using two methods frequency of occurrence method, and the score bulk estimate method revealing a predominantly piscivorous diet. The diet consisted of about 14 species out of which 69.53% is constituted of non–native fish species (Oreochromis mossambicus, Labeo rohita, Cyprinus carpio, and Cirrhinus cirrhosus). Ecotoxicological assessments were performed on water, sediment, fish, and spraint samples to evaluate the presence of potentially toxic elements (PTEs). While PTE concentrations in water and sediment were generally below harmful thresholds, their presence poses a long-term risk through bioaccumulation. Risk assessment indicated significant potential health risks from metals like mercury and arsenic, which could impact otter heal