Also known as the SuSu for the sound made when they breathe at the water’s surface, the remaining population of Ganges River dolphin (Platanista gangetica gangetica) is estimated to be less than 2000 animals. It is one of two subspecies of South Asian River dolphin, the other being the Indus River dolphin or Bhulan (Platanista gangetica minor) with a similar, limited population size.
The Freshwater Dolphins
The South Asian River dolphins, as they are collectively known, may be among the most primitive mammals left in the world and they are highly endangered. With the extinction of the baiji (Lipotes vexilifier), they are one of two surviving freshwater dolphin species, the other being the Amazon River dolphin (Inia geoffrensis), which is listed as vulnerable to extinction as well.
Threats to the Ganges River Dolphin
Habitat loss and degradation top the list of concerns for the future of the SuSu. Dams, canals and barrages which divert water for irrigation are all altering the Ganges River, resulting in fragmentation of dolphin populations and alterations in fish and invertebrate species which are food sources for the SuSu.
Silt from deforestation along with industrial and agricultural contaminants pour into the river. Water diverted for industry, agriculture and flood control lowers river levels, reducing the Ganges’ ability to dilute these contaminants.
The Ganges River dolphin is still hunted as a food source by tribes of the upper Brahmaputra. In other areas, fishermen, who see the dolphins as competition for limited food resources, have a second reason to kill them. Their oil is an excellent fish attractant.
Even without deliberate killing by fishermen, the Ganges River dolphin is harmed by fishing activities. A blind species, which hunts by sound in the murky waters of the River, they are commonly entangled in gillnets.
Protection for Ganges River Dolphins Falls Short
Legal protection for the SuSu has been in place for some time. Enforcement, however, has been limited. Alternatives for dolphin oil as a fish attractant are being developed and several sections of the Ganges have been declared river dolphin sanctuaries. A few animals have been translocated after being found in irrigation canals or isolated rivers.
Efforts to clean up the Ganges and Brahmaputra have been limited but there are some changes underway. A scientifically trained Hindu priest is heading up a pilot program for sewage treatment in Varnasi. If Veer Bhadra Mishra’s program works it is likely to be used in other cities along the Ganges, where the government’s own Ganga Action Plan for building wastewater treatment plants has failed. It is a small step but it is important as an indication of the growing awareness of environmental concerns in India.
The connection between the health of the rivers of India and the survival of the Ganges River dolphin is clear. Hunting, fishing and entanglement issues can be eased by offering alternatives such as the fish oil attractant, developing ecotourism-based income for the fishermen and educating local people on the value of this freshwater dolphin. Wise management of water and control of industrial and agricultural discharge are more complex issues but they must be addressed if the Ganges River dolphin and its habitat are to survive.
Dawn M. Smith - A vet nurse, Dawn has worked in wildlife rehabilitation and conservation around the world in addition to her veterinary hospital ...
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