On the Behaviour, abundance, habitat use and potential threats of the Gangetic Dolphin Platanista gangetica in southern West Bengal, India

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Mahua Roy Chowdhury
Sangita Mitra
Saswati Sen


The Ganga River Dolphin Platanista gangetica Roxburgh, 1801 is a globally endangered cetacean found in the River system of Ganga, Brahmaputra and Meghna in Bangladesh and India.  A survey and research were conducted from 2012–2014 to explore the behaviour, abundance, habitat use and potential threats of the Dolphin in the lower, middle and upper stretches of the river Ganga and its tributaries in southern West Bengal.  The study recorded different types of surfacing patterns with respect to their age class as well as on diurnal activity pattern of the individual. The adults and sub-adults were found to have different types of surfacing during different hours of the day.  The morning and afternoon were observed to be feeding hours of the Dolphin.  Multiple potential threats were encountered during the present study such as destructive fishing gears, dumping of solid and municipal waste, industrial effluents, agricultural run-off, construction of water structures, water extraction and reduction of river depth attributed to siltation.  These factors contributed to the present study of the river dolphins in the Ganga, which are localised at certain pockets in good number. 


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Author Biographies

Mahua Roy Chowdhury, WWF-India, West Bengal State Office, Tata centre, 1st Floor 43 Jawaharlal Nehru Road, Kolkata, West Bengal 700071, India



Sangita Mitra, “Ananda Nilayam”, 2/21 6th Main Road, Kasturibai Nagar, Adyar, Chennai, Tamil Nadu 600020, India Present address: National Biodiversity Authority, TICEL Bio park, 5th floor, CSIR Road, Taramani, Chennai, Tamil Nadu 600113, India

Former coordinator, WWF-INDIA

Saswati Sen, WWF-India, West Bengal State Office, Tata centre, 1st Floor 43 Jawaharlal Nehru Road, Kolkata, West Bengal 700071, India

State Director, WWF-INDIA


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