M Sc Dissertation(WII)

Permanent URI for this collectionhttp://192.168.202.180:4000/handle/123456789/3

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Author: search.filters.author.Johnson, J.A.Subject: search.filters.subject.Distribution

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    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, Ruchika
    Smooth-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
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    See Through Sound : Understanding the Pattern of Habitat use by Ganetic River Dolphin in the Kaziranga Part of Brahmaputra River
    (Wildlife Institute of India, Dehradun, 2019) Abhishek, B.; Qureshi, Qamar; Johnson, J.A.
    Studying the habitat and its associated features is important because of its driving factors that limits the abundance and distribution of a species. This study mainly focuses upon the abundance, distribution, activity and habitat use pattern of Gangetic river dolphins in part of the Brahmaputra River that flows through Kaziranga National Park. The abundance of Gangetic river dolphin and its relatedness to the different habitat features of the river and fish species were studied. The 92 km length of river in the study area was divided in to 43 segments, which were further broadly classified in to different river morphology.