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New Delhi, India

Sasaki-Yamamoto Y.,Kyoto University | Akamatsu T.,Japan National Research Institute of Fisheries Engineering | Akamatsu T.,Japan Science and Technology Agency | Ura T.,Tokyo University of Science | And 5 more authors.
Marine Mammal Science | Year: 2013

We monitored the underwater movements of Ganges River dolphins using stationed stereo acoustic data loggers. We estimated these movements using changes in the relative angle of the sound source direction (trajectory). Of the total acoustic recordings (66 h), 26.2% contained trajectories of dolphins, and 78.6% of these trajectories involved single animals, suggesting that dolphins tended to swim alone and were localized near the monitoring station. The observed trajectories were categorized as follows: staying type characterized by small changes in the sound source direction, moving type A (moving in the same direction), and moving type B (moving up and down the stream during recording). The average interpulse intervals of sounds in moving types A and B were significantly shorter than that of the staying type, suggesting that dolphins produce the former types of trajectories to echolocate across shorter distances during movement. The frequency of occurrence of moving type A increased during the night, whereas that of type B increased in the late afternoon and that of the staying type increased during the daytime. These results indicate that dolphins moving at night tended to use short-range echolocation, whereas during the day, they remained in relatively small areas and used long-range sonar. © 2012 by the Society for Marine Mammalogy. Source

Midha N.,WWF India | Mathur P.K.,Wildlife Institute of India
Environmental Management | Year: 2014

The Sharda River creates and maintains the ecologically diverse remnant patches of rare Terai ecosystem in northern India. This study used repeat satellite imagery and geographic information system analysis to assess the planform dynamics along a 60 km length of the Sharda River between 1977 and 2001 to understand the altered dynamics and its plausible causes in this data-poor region. Analyses revealed that the Sharda River has undergone significant change corresponding to enhanced instability in terms of increased number of neck cut-offs and consistent occurrence of avulsions in subsequent shorter assessment periods. An increased channel area (8 %), decreased sinuosity (15 %), increased braiding intensity, and abrupt migrations were also documented. The river has migrated toward the east with its west bankline being more unstable. The maximum shifts were 2.85 km in 13 years (1977-1990), 2.33 km in next 9 years (1990-1999), and a substantial shift of 2.39 km in just 2 years (1999-2001). The altered dynamics is making the future of critical wildlife habitats in Kishanpur Wildlife Sanctuary and North Kheri Forest Division precarious and causing significant economic damage. Extensive deforestation and expansion of agriculture since the 1950s in the catchment area are presumed to have severely impacted the equilibrium of the river, which urgently needs a management plan including wildlife habitat conservation, control, and risk reduction. The present study provides a strong foundation for understanding channel changes in the Sharda River and the finding can serve as a valuable information base for effective management planning and ecological restoration. © 2013 Springer Science+Business Media New York. Source

Chakraborty S.,Jawaharlal Nehru Centre for Advanced Scientific Research | Chakraborty S.,Indian Institute of Science | Boominathan D.,WWF India | Desai A.A.,WWF India and WWF International | Vidya T.N.C.,Jawaharlal Nehru Centre for Advanced Scientific Research
Conservation Genetics | Year: 2014

With growing human and, possibly, elephant populations and a drastic increase in anthropogenic activities, human-elephant conflict in Asia has been on the rise. The Alur area in Karnataka state, southern India, is one such case in point, which has witnessed increasing levels of human-elephant conflict over the last two decades. The tiny, moderately protected habitat available for elephants in this human-dominated landscape does not appear to be able to support elephants over the long term. Options to deal with the escalating conflict include translocation of elephants, bringing elephants into captivity, and culling. We carried out a molecular genetic study of elephants in the Alur area to estimate the minimum number of elephants using the area, the sex ratio, genetic relatedness between individuals, and genetic structure with regard to the larger population in the landscape, so that informed management decisions could be made. Fresh dung samples were collected from the field and genotyped using 12 microsatellite loci. We found 29 unique individuals in the population, comprising 17 females and 12 males of different age classes. Relatedness between females suggested independent colonisations by discrete, small groups rather than by one cohesive clan of related females. This obviates the need for a single solution for dealing with all the females in the area in order to maintain social integrity, and has implications in terms how these elephants can be dealt with. We demonstrate how social organization inferred through molecular data from non-invasive sampling can inform management decisions. © 2014 Springer Science+Business Media Dordrecht. Source

Choudhary S.,Tilka Manjhi Bhagalpur University | Dey S.,Tilka Manjhi Bhagalpur University | Sagar V.,WWF India | Nair T.,Wildlife Conservation Society | And 2 more authors.
Aquatic Conservation: Marine and Freshwater Ecosystems | Year: 2012

River flow regulation and fragmentation is a global threat to freshwater biodiversity, ecosystem processes, and associated human activities. Large dams in the Ganges river basin of the Indian subcontinent have severely altered natural flow regimes, particularly in the low-flow dry season. Altered flows could have negative impacts on endangered species such as the Ganges river dolphin Platanista gangetica. Habitat use by river dolphins was investigated in relation to river channel depth and morphology, over 332km of the flow-regulated Gandak River in India. Dolphin distribution patterns were compared across multiple spatial scales in the Gandak, Kosi, Chambal, Sone Rivers and the upper and lower sections of the Ganges main stem. Dolphin presence was recorded in 40% of segments in the Gandak river, with a best count of 257 (range 250-267) and average individual encounter rates at 0.75 dolphins km -1 (SD 0.89). Bayesian zero-inflated spatial models showed that river dolphin abundance was positively influenced by river depth, presence of meanders and corresponded closely with gillnet fishing. Minimum mid-channel depth requirements were estimated at 5.2m for dolphin adults and between 2.2 and 2.4m for mother-calf pairs. Adult dolphins showed highly similar habitat preferences across regulated or unregulated rivers, for depths >5m, and meandering channels. Dry-season habitat availability was reduced as the degree of flow regulation increased across rivers, mainly owing to loss of lateral and longitudinal channel connectivity. Overall encounter rates were reduced from >3km -1 in less regulated stretches, to <0.3km -1 in regulated rivers. Clustering of dolphins in deep pools increased along the gradient of river flow reduction, with dolphins almost absent from intervening segments because of low flow rates. These results indicate the importance of maintaining adequate dry-season flows to ensure river habitat availability and connectivity for dolphins. © 2012 John Wiley & Sons, Ltd. Source

Shahnawaz Khan M.,WWF India
IUCN/SCC Otter Specialist Group Bulletin | Year: 2015

Decline in the populations of the Smooth-coated Otter throughout its range of distribution and a perception that it is a 'keystone species' for riverine ecosystem stirred the idea of the presented paper. The species inhabits major freshwater wetlands throughout the south and south-east Asia and often comes into the direct conflict with humans for food and habitat. Further the species is also suffering with neglecting attitude and mismanagement due to lack of baseline information. Thus WWF India initiated the conservation work towards the documentation of the distribution of the species in Punjab in 2010. State wide population assessment surveys and secondary information obtained shows the occurrence of smooth-coated otters along some stretches of Rivers Beas, Sutlej and Ravi and Harike wetland in Punjab. Source

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