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

Main Article Content

Mahua Roy Chowdhury
http://orcid.org/0000-0002-2869-6877
Sangita Mitra
http://orcid.org/0000-0003-2486-3196
Saswati Sen
http://orcid.org/0000-0002-4372-2690

Abstract

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. 

 

Article Details

How to Cite
[1]
Chowdhury, M.R., Mitra, S. and Sen, S. 2016. On the Behaviour, abundance, habitat use and potential threats of the Gangetic Dolphin Platanista gangetica in southern West Bengal, India. Journal of Threatened Taxa. 8, 9 (Aug. 2016), 9131–9137. DOI:https://doi.org/10.11609/jott.1752.8.9.9131-9137.
Section
Communications
Author Biographies

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

PROJECT ASSCOCIATE, CONSERVATION SECTION

 

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

References

Anderson, J. (1879). Anatomical and Zoological researches comprising an account of zoological results of the two expeditions to western Yunnan in 1868 and 1875; and a monograph of the two cetacean genera, Platanista and Orcella, B. Quatrich, London.

Bashir, T. (2010). Ganges River Dolphin (Platanista gangetica) seeks help. Current Science 98 (3): 287–288; http://dx.doi.org/10.11609/jott.o2333.1087-91

Biswas, S.P. & S. Baruah (2000). Ecology of river dolphin (Platanista gangetica) in the Upper Brahmaputra. Hydrobiologia 430: 97–111; http://dx.doi.org/10.1023/A: 1004077215276

Braulik, G.T. (2006). Status assessment of the Indus River dolphin, Platanista gangetica minor, March–April 2001. Biological Conservation 129: 579–590; http://dx.doi.org/10.1016/j.biocon.2005.11.026

Chatterjee, M., D. Shankar, G.K. Sen, P. Sanyal, D. Sundar, G.S. Michael, A. Chatterjee, P. Amol, D. Mukherjee, K. Suprit, A. Mukherjee, V. Vijith, S. Chatterjee, A. Basu, M. Das, S. Chakraborti, A. Kalla, S.K. Mishra, S. Mukhopadhyay, G. Mandal & K. Sarkar (2013). Tidal variation in the Sundarbans estuarine system, India. Journal of Earth System Science 122(4): 899–933.

Choudhary, S., S. Dey, S. Dey, V. Sagar, T. Naird & N. Kelkar (2012). River dolphin distribution in regulated river systems: implications for dry-season flow regimes in the Gangetic basin. Aquatic Conservation: Marine and Freshwater Ecosystems 22: 11–25; http://dx.doi.org/10.1002/aqc.1240

Choudhury, A.U. (2013). The Mammals of North East India. Gibbon Books (Guwahati) and the Rhino Foundation for Nature in North East India (Guwahati), 221–222.

Choudhury, A. & S. Mitra (2014). Assessing sustainable livelihood strategies for fisheries communities during Hilsa fishing ban period in West Bengal, India. IUCN, 52pp.

Chugh, R.S. (1961). Tides in Hooghly River. Hydrological Science Journal 6(2): 10–26.

De, D.K. (2014). The Shad Hilsha, Tenualosa ilisha (Hamilton) - Its biology and fisheries. CIFRI, 166: 6–7.

IUCN (2010). IUCN Red List of Threatened Species. Version 2010.4. . Downloaded on 12 November 2010.

Jones, S. (1982). The present status of the Gangetic Susu, Platanista gangetica (Roxburgh) with comments on the Indus Susu P. minor (Owen). FAO Fisheries Series 5: 97–115.

Kasuya, T. & A.K.M.A. Haque (1972). Some information on the distribution and seasonal movement of the Ganges dolphin. The Scientific Report of the Whales Research Institute (Tokyo) 24: 109–115.

Kelkar, N., J. Krishnaswamy, S. Choudhary & D. Samaria (2010). Coexistence of fisheries with river dolphin conservation. Conservation Biology 24: 1130–1140; http://dx.doi.org/10.1111/j.1523-1739.2010.01467.x

Kreb, D. & Budiono (2005). Conservation management of small core areas: key to survival of a critical endangered population of Irrawaddy river dolphins Orcaella brevirostris in Indonesia. Oryx 39(2): 1–11.

Mohan, R.S.L., S.C. Dey, S.P. Bairagi & S. Roy (1997). On a survey of Ganges River dolphin Platanista gangetica of Brahmaputra River, Assam. Journal of the Bombay Natural History Society 94: 483–495.

Reeves R.R. & S. Leatherwood (1994). Dams and river dolphins: can they coexist? Ambio 23: 172–175.

Reeves, R.R. & J.R.L. Brownell (1989). Susu Platanista gangetica (Roxburgh, 1801) and Platanista minor (Owen, 1853), pp. 69–99. In: Ridgway, S.H. & R. Harrison (eds.). Handbook of Marine Mammals. Academic Press, London.

Rudra, K. (2008). The encroaching Ganga and social conflicts, The case of West Bengal. Publisher? Total number of pages?

Shrestha, T.K. (1993). Ecology, status appraisal, conservation and management of Gangetic Dolphin Platanista gangetica in the Koshi River of Nepal. Journal of Freshwater Biology 5(1): 93–105.

Sinha, R.K. (1997). Status and conservation of Ganges River dolphin in Bhagirathi-Hooghly River systems in India. International Journal of Ecology and Environmental Sciences 23: 343–355.

Sinha, R.K. (2002). An alternative to dolphin oil as a fish attractant in the Ganges River system: conservation of the Gangetic River Dolphin. Biological Conservation 107: 253–257.

Sinha, R.K., S.K. Sinha, G. Sharma & D.K. Kedia (2010b). Surfacing and diving behaviour of free-ranging Ganges River Dolphin, Platanista gangetica gangetica. Current Science 98(2): 230–236.

Smith, B.D., M.A.A. Diyan, R.M. Mansur, E.F. Mansur & B. Ahmed (2010). Identification and channel characteristics of cetacean hotspots in waterways of the eastern Sundarbans mangrove forest, Bangladesh. Oryx 44: 241–247.

Smith, B.D. & G.T. Braulik (2012). Platanista gangetica. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. www.iucnredlist.org. Downloaded on 02 April 2014.

Smith, B.D., A.K.M. Haque, M.S. Hussain & A. Khan (1998). River dolphins in Bangladesh: conservation and the effects of water development. Environmental Management 22: 323–335.

Smith, B.D., G. Braulik, S. Strindberg, R. Mansur, M. Diyan & B. Ahmed (2009). Habitat selection of freshwater-dependent cetaceans and the potential effects of declining freshwater flows and sea-level rise in waterways of the Sundarbans mangrove forest, Bangladesh. Aquatic Conservation: Marine and Freshwater Ecosystems 19: 209–225; http://dx.doi.org/10.1002/aqc.987

Smith, B.D., R.K. Sinha & K. Zhou (2000). Register of water development projects affecting Asian river cetaceans, pp. 22–39. In: Reeves, R.R., B.D. Smith & T. Kasuya (eds.). Biology and Conservation of Freshwater Cetaceans in Asia. Occasional Papers of the IUCN Species Survival Commission. IUCN, Gland, Switzerland.

Wakid, A. (2005). Conservation of Gangetic Dolphin in Brahmaputra River System, India. Final Technical Report submitted to the BP Conservation Programme and Rufford Small Grant, 80pp.

Wakid, A. (2006). Status and distribution of a newly documented residential Gangetic Dolphin (Platanista gangetica Roxburgh 1801) population in eastern Assam. Journal of the Bombay Natural History Society 102: 158–161.

Wakid, K. & G. Braulik (2009). Protection of endangered Gangetic Dolphin in Brahmaputra River, Assam, India. Final report to IUCN-Sir Peter Scott Fund, 44pp.