Technical Reports

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Study on ecology and migratory patterns of golden mahseer (Tor putitora) in river Ganga using radio telemetry techniques
(Wildlife Institute of India, Dehradun, 2021) Johnson, J.A.; Dhawan, B.; Sivakumar, K.
Golden Mahseer, Tor putitora is popularly known as ‘Himalayan mahseer’ and it is one of the largest freshwater fishes of India It occurs along the mid-hills stretch of Himalayan region including Shivaliks and part of Terai landscape. Over the years, the golden mahseer populations and their habitats have depleted due to various anthropogenic activities, hence, it is listed as an Endangered species in the IUCN Red List. Due to rapid hydro-power developments in the river valleys, habitats of golden mahseer have been fragmented, which in turn affects the ecology and spawning biology of golden mahseer. In order to, understand ecology, habitat use and movement pattern of golden mahseer, this project was proposed in 2017. The study was carried out in the two river systems of Western Himalaya: Kosi river in Ramnagar and Kolhu river in Kotdawar. To study the movement and migratory patterns of golden mahseer, 11 individuals were tagged with radio telemetry tags in the month of June (before onset of monsoon) to understand the migratory behaviour of tagged individuals. Manual tracking and monitoring were performed for all the tagged individuals to get location points and to generate movement data during the period from June-October, 2019. Correspondingly, information related to the fish habitat-type, depth, velocity, temperature and weather was collected. Simultaneously, habitat inventory was performed in three zones in both the rivers; upper, middle and down streams. At each zone 200-meter stream reach was selected for assessment of habitat availability, habitat use by different life history stages of golden mahseer (fingerlings, juveniles and adults). This study was performed for three seasons: Post-winter (March-April), Pre-monsoon (May-early June) and Post-Monsoon (October-November) during 2018-2019. Adults of the golden mahseer were mostly found in deep waters (> 2 m) with cool temperature (18-23o C) and low water velocity (0-0.4m/s). Adults prefer pool habitats with sand and gravel/cobbles as the dominant substratum. Similarly, availability of juveniles and fingerlings were recorded along the river basins and mapped to see the available nursery grounds of the golden mahseer. Habitat preference and microhabitat use were analysed for the available nursery grounds. The results for both the rivers exhibited backwater pools, secondary channels and run habitats as highly used habitats of fingerlings. And, run habitats were mostly as used habitats by juveniles in these rivers. Fingerlings were mostly seen at depth ranges (0.1-0.6m) with velocity (0-1.2m/s) where dominant substratum was gravel and sand. Similarly, depth range between (0.3- >1.8m), moderate velocity (0.3- >1.2m/s) and habitats with cobbles, bed rock and gravel as substrate were used by the juveniles. Based on the habitat availability and use by golden mahseer, Habitat Suitability Curves (HSC’s) for the youngs were formulated. The study revealed that variation in the habitat use by the fish, significantly varied during the monsoons. In the present study, we also recorded other fish species co-existing with golden mahseer in Kosi and Kolhu. Various threats which harm the golden mahseer population and their habitats in Kosi and Kolhu river were recorded and possible conservation measures are discussed
Spatial mapping of important marine habitats of Malvan Coast for re-organization of boundary of the Malvan Marine Sanctuary
(Wildlife Institute of India, Dehradun, 2023) Shinde, N.; Bayana, S.; Sarkar, D.; Pande, A.; Sivakumar, K.; Talukdar, Gautam
Malvan Marine Sanctuary is a Marine Protected Area located in the Sindhudurg district of Maharashtra state. Known for its rich biodiversity, it is grappling with increasing anthropogenic pressure necessitating a comprehensive study to assess its habitats and threats. Management Effectiveness Evaluation (MEE) of 2017-2018 team had suggested for boundary reorganization to exclude areas of human intervention and to include important habitats and areas with high biodiversity for the better management of biodiversity off the coast of Malvan. The project has undertaken because high tourism zone are areas with high anthropogenic pressure within the core zone of the sanctuary. Coral reefs and its associated fish fauna were surveyed at nine sampling sites. The total hard coral cover was observed to be 28% while the seagrass cover was observed to be 3% in 21 sampling sites. 19 genera of corals were identified. Favites sp.was observed to be the most abundant (19.18%). Within the sanctuary, Seagrass patches were identified at five sampling sites namely King’s Garden 1, King’s Garden 2, King’s Garden 3, Dharan and Donor site. 122 species of fish belonging to 38 families were observed during underwater surveys. Fish-market surveys were conducted to study the species composition and size-class of fish species caught around the sanctuary. A total of 44 different fish species were observed during market surveys. Beach litter surveys were conducted to assess the anthropogenic stress along the Malvan coastline. Debris in the form of polythene was the major contributing litter type at all three sections of the beach. The rocky outcrops along the coast were observed to be roosting sites for avifaunal species namely, White-bellied Sea Eagles, Pigeons, Swiftlets, etc. Spatial prioritization of the marine habitats revealed potential PA’s include Kawda, 7 rocks, Lighthouse area, covering an area of 29.07 sq.km; conservation priority areas comprising Chiwla, and Sargassm covering a total area of 19.21 sq. km and King’s garden (3.534 sq km) as sensitive area. Strategies to conserve these areas for long term conservation. should be planned. Spatial mapping of important marine habitats of Malvan coast for re-organization of boundary of the Malvan Marine Sanctuary

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