PhD Theses (WII)
Permanent URI for this collectionhttp://192.168.202.180:4000/handle/123456789/104
Browse
3 results
Search Results
Item An ecological study on nesting patterns and Behavioural dynamics of vultures in Kangra valley, Himachal pradesh(Wildlife Institute of India, Dehradun, 2025) Bhattacharya, MalyasriVultures are nature’s most efficient scavengers, playing a critical role in maintaining ecological balance. Their populations in India have suffered a drastic decline from 97-99% between 1993 and 2002, leading to the establishment of captive breeding programs aimed at species recovery. Threats of decline have now stabilized, but little is known about the ecology and survival of the vultures in the wild, necessitating this study for the conservation of vultures in their natural habitat. Kangra Valley, situated in the westernmost region of Himachal Pradesh state in India, is one of India's important vulture sites, supporting most of the nine vulture species recorded in the country. Among these, the White-rumped Vulture (Gyps bengalensis), Egyptian Vulture (Neophron percnopterus), Bearded Vulture (Gypaetus barbatus), Himalayan Griffon (Gyps himalayensis), and Eurasian Griffon (Gyps fulvus) are the most observed, while the Cinereous Vulture (Aegypius monachus), Red-headed Vulture (Sarcogyps calvus), Slender-billed Vulture (Gyps tenuirostris), and Indian Vulture (Gyps indicus) are recorded occasionally. Kangra is also one of the most densely populated districts of Himachal Pradesh, with an extensive road network, contributing to anthropogenic pressures on vulture populations. While the region has a long history of vulture census efforts, aspects of their breeding ecology remain poorly understood. Why do they select a particular tree for nesting? What are the variables that affect nest site selection? What is the nest success rate? Where do they move, and what is their home range? What are the threats? This study, conducted between 2019 to 2024, focuses on the breeding ecology of White-rumped Vultures in Kangra, examining their nesting preferences, reproductive success, threats to nesting colonies and spatial movements. Additionally, the research explores the climatic niche availability for all nine vulture species found in the region, assessing current and future climatic scenarios to predict potential habitat suitability. The Chir Pine forests of Kangra serve as the breeding habitat for White-rumped Vultures in the region. The breeding season of the White-rumped Vulture (Gyps bengalensis) in the area extends from November to April, encompassing mating, incubation, hatching, and fledgling development, lasting approximately 25-28 weeks (October—April). Over three consecutive breeding seasons (2021-2024), the study recorded 17 active nesting colonies with a total of 617 active nests, primarily in Chir Pine (Pinus roxburghii) trees. Nest site selection was influenced by tree characteristics, with vultures preferring trees with a larger girth at breast height (GBH) (average GBH of 254.8 cm + 49.3 SD), lower canopy cover (5-10%), greater shrub density (77-100%), and proximity to other nesting trees and water sources. Conversely, areas with high fire activity, dense canopy cover, and limited nearby trees were found to be less suitable. In addition to breeding ecology, the study identified 36 carcass dumping sites in the region. These sites, managed by local communities, serve as designated areas for livestock carcass disposal, primarily for cattle and buffalo. The carcasses are transported from households to the dumping sites by local cobblers, locally known as "Harijans." The decline of open carcass disposal areas has posed further challenges for vulture populations. To understand movement patterns, five wild White-rumped Vultures were satellite-tagged in Kangra, Himachal Pradesh, in 2021. The tagged individuals exhibited extensive movements, ranging across Jammu & Kashmir, the Pakistan border near Punjab, and Uttarakhand. Three of these vultures have consistently nested in Dolba and Lapiana within Kangra between 2021 and 2024. The study recorded an average home range of 1367.6 km? for non-breeding individuals and 1719.8 km? for breeding individuals across seasons. The future distribution for the nine vulture species shows a significant decline in the modeled climatic niche for seven vultures by 2041-2060 and 2061-2080. The study identified electrocution, forest fires and poisoning as major threats, with notable vulture fatalities recorded. Major forest fire-prone areas include Gopalpur, Pathiar Range, Lunj, and Baranj Sirmani. This study offered insights into India's largest documented aggregation of 617 White-rumped Vulture nests. The study recommends targeted conservation interventions to ensure the long-term survival of White-rumped Vultures. These include the protection of nesting sites, preservation of old-growth forests, and support for cobbler communities engaged in carcass disposal. Additionally, designated vulture feeding stations within forested areas should be established. Given these findings, the study proposes designating the region as a Vulture Safe Zone, suitable areas for releasing captive-bred vultures with continuous monitoring. Himachal Pradesh Forest Department (HPFD) and the Ministry of Environment and Climate Change (MoEFCC) have to come up with guidelines to declare a vulture safe zone as well as a strategic conservation plan to safeguard this critically endangered species.Item Patterns of structural and functional attributes of alpine meadows of temporal scale in Tungnath, Western Himalaya(Wildlife Institute of India, Dehradun, 2023) Kumar, RahulThe present study was carried out to understand the temporal changes in structural (richness, diversity, of alpine communities, above and belowground biomass, net biomass accumulation/productivity, and carbon density) and functional attributes (Phenology of species recorded) of different alpine plant communities of alpine meadows. This research work has not only generated information on baseline ecological characteristics of species and communities but also provides valuable management implications. The study is summarized in the following paragraphs. The major objectives of the study are: 1. To study temporal changes in composition, structure, and functional attributes across various herbaceous communities, 2. To study the phenological patterns of dominant plant species across various communities in relation to abiotic parameters (rainfall/snowfall and temperature), 3. To assess the patterns of biomass production, carbon storage and sequestration in various communities and temporal dynamics of soil nutrients The study was carried out in Tungnath region of Western Himalaya which lies on outer fringe of Kedarnath Wildlife Sanctuary in the upper catchment of the river Mandakini, a major tributary of the Alaknanda, which finally join the river Ganga at Devprayag. Climate change particularly endangers organisms with fragmented habitat distribution, especially those with narrow ecological ranges, which may lead to extinction. Cold-adapted species are especially vulnerable in high alpine meadows due to rapid warming, potentially exceeding their adaptive capacity. The alpine zone covers 9 % of the total area in Greater Himalaya. In Uttarakhand, there are 5 protected areas encompassing alpine region namely Nandadevi National Park (NP), Valley of Flowers NP, Govind Pashu Vihar NP, and Wildlife Sanctuary (WS), Kedarnath WS and Askot WS of which except Nandadevi NP and Valley of Flowers NP, others are heavily exploited leading to habitat degradation. Exploitative practices such as unsustainable pastoralism, excessive extraction of medicinal plants, pilgrimage pressure, and poorly planned developmental projects are major challenges faced by alpine ecosystems in the Greater Himalaya. Therefore, it is crucial to understand species and community ecology to identify stress mechanisms and develop effective conservation strategies in Greater Himalaya. Numerous studies have shown correlations between temperature, precipitation, productivity, plant interactions, spatial patterns, and species richness in alpine ecosystems outside of the Himalayas. However, knowledge about the Himalayan alpine regions is limited due to their micro-topographic variations, altitudinal gradient, temperature range, and precipitation patterns, which make it challenging to isolate specific variables responsible for environmental-species relationships. These issues can lead to smaller population sizes, habitat degradation, and local extinctions, putting immense stress on alpine meadows. To address these challenges and conserve alpine meadows, it is essential to study sustainable land use practices adopted by local communities and develop conservation plans tailored to specific sites and species.Item The Spatial Ecology and Conservation of Seagrasses of the Gulf of Kachchh, Gujarat(Wildlife Institute of India, Dehradun, 2024) Pathan, Sameeha Vahedkhan; Sivakumar, K.Seagrass ecosystems provide ecosystem services that rank among the highest in economic valuation worldwide. They also provide a range of economic, social, and environmental goods and services, which greatly increase coastal communities' resilience to the impacts of climate change. As unique marine habitats, seagrass ecosystems provide shelter and food for marine species during different life stages and contribute to sediment accretion and primary production. The high diversity of marine plant and animal life supports tourism activities and provides the raw materials for medicinal, agricultural, and structural applications. Furthermore, the physical structure of seagrass ecosystems attenuates wave height and speed, protecting coastlines from erosion and storm surges. Threats to seagrass ecosystems in the coastal areas of the Gulf of Kachchh include pollution, rising sea levels, eutrophication, reduction of light intensity and die-back. These all negatively impact seagrass ecosystems, such as increasing growth of epiphytes, sediment anoxia, or increased prevalence of diseases. Further, the effects of climate change on seagrass ecosystems will be additional stressors. The underlying factors affecting seagrass ecosystems are direct human pressures such as pollution, disturbances, and eutrophication. The combined stressors – human pressures and climate change impacts – are likely to exceed the thresholds for seagrasses, leading to, among other things, i) redistribution (reduction and coastal migration) of existing habitats and ii) widespread seagrass ecosystem die-off. In this context, this study was conducted between January 2018- March 2022 and aimed to understand the phenology, biomass and spatial distribution patterns of seagrasses of the GoK, using which I attempted to understand the foraging behaviour, habitat use and movement ecology of dugongs in the Gulf of Kachchh. The major objectives of the study include a) Mapping the distributional characteristics and patterns of seagrass meadows in the southwestern GoK, b) understanding the seasonal variations in the abundance of seagrasses on topographically distinct meadows, c) investigating fine-scale and topographical determinants of dugong habitat preferences and d) to assess the role of semi-diurnal tides' influence on dugong foraging habitats.