The elusive freshwater dolphin of the sacred Ganga

world/Asia/Asia_july_10/ganga_dolphin_release

Gangetic dolphin being released back into the river. Photo credit Dr Sandeep Behera/WWF.

Written by Shubhobroto Ghosh

Think of the word dolphin and the immediate image that is conjured is one of Bottlenosed Dolphins in the ocean which has made them the visual representative of all dolphins. However it comes as a surprise to some people to learn that there are several species of dolphin, like the Gangetic River Dolphin, that are also found in freshwater systems, rivers and lakes. These animals are not as eye catching and attractive as their sea dwelling partners but nonetheless they are endangered and of great ecological importance.

Six species of Freshwater dolphin
The Gangetic River Dolphin is one among six species of freshwater river dolphins that exist in the world today, found in rivers of Asia and South America. The Gangetic River Dolphin (Platanista gangetica gangetica) and Indus River Dolphin (Platanista gangetica minor) are the two sub species of freshwater dolphins found in India, Nepal, Bangladesh and Pakistan.

Echolocation
Gangetic River Dolphins have the long, pointed noses characteristic of all river dolphins. The teeth are visible in both the upper and lower jaws even when the mouth is closed. The snout thickens towards its end. The species does not have a crystalline eye lens, rendering it effectively blind, although it may still be able to detect the intensity and direction of light. Navigation and hunting are carried out using echolocation. They are unique among cetaceans in that they swim on their side.

Just 2000 alive
In India, one can see these beautiful cetaceans along river reaches in Assam, Bihar, Jharkhand, Madhya Pradesh, Rajasthan, Uttar Pradesh and Bengal. Research studies under the Ganga Action plan in the 1980s estimated that around 6000 dolphins were present in its distribution range across the Ganga-Brahmaputra-Meghna and Karnaphuli river systems. Sadly today the population level is estimated to be around 2000.

Indicator species
Just like the tiger in a forest ecosystem, the Gangetic River Dolphin is an indicator species for the river ecosystem. It is at the apex of the food chain and is an endemic and rare charismatic animal found only in the Indian sub-continent. The animal has been known historically for ages and has a range of local names. The creature has been mentioned in the Babarnama; The Gangetic River Dolphin is also said to be the first animal that followed Bhagirath who was bringing the Ganga (Ganges).

The Gangetic River Dolphin is listed on Appendix I of CITES (Convention on International Trade in Endangered Species) and is classified as ‘Endangered’ by the IUCN (International Union for Conservation of Nature). Over the years, WWF, in collaboration with other groups and the government has undertaken several initiatives to save this animal that has now been designated as the National Aquatic Animal of India.

WWF India initiated a conservation programme for the Gangetic River Dolphin in 1997. This began with a series of surveys and field visits to specific stretches and to surrounding villages in the habitat of this animal.

Upper Ganga
WWF has concentrated its work on this species in the upper Ganga River, in the stretch between Bijnor and Narora in Uttar Pradesh in India in coordination with the Uttar Pradesh Forest Department. The total length of this stretch is 165 km. The work included involvement with local communities, using the cultural and religious importance of the Gangetic River Dolphin as an icon of saving our rivers. Although covering just a small section of the river, the project illustrated the potential for applying similar approaches at a much wider scale to promote a locally based stewardship ethos.

The project involves mapping of the existing land use of the region with a focus on the river basin. The project highlights the threats to indicator aquatic species with a special emphasis on Gangetic Dolphins and other higher vertebrates such as Gharials and turtles. WWF also developed digitized maps to identify and prioritise areas that require immediate protection and intervention in terms of river threats.

Cow of the Ganges
“The Gangetic River Dolphin is an aquatic mammal present in our river ecosystem and is an icon of the Ganges. Also known as the cow of the Ganges, the creature has religious significance. The animal is an indicator of good water quality,” says Dr Sandeep Behera, Associate Director, River Basins and Biodiversity programme, WWF India.

WWF has conducted research on habitat utilization of Gangetic River Dolphins. Monthly maps of these sightings are prepared. When dolphins are sighted, their numbers are determined using several criteria including the number of dolphins surfacing simultaneously and the size of the dolphin. During these studies, selected water quality parameters are also collected to note the habitat utilization of the species. WWF India has also collaborated with IIT Delhi and University of Tokyo for acoustic research to understand the underwater behaviour of this species.

 

Changes in fishing practices have deprived the dolphins of some of their diet. Photo credit Dr Sandeep Behera/WWF.

Changes in fishing practices have deprived the dolphins of some of their diet. Photo credit Dr Sandeep Behera/WWF.

Diet of small fish
WWF research shows dolphins prefer to stay in deeper stretches of rivers where they get good cover. Gangetic River Dolphins feed on small fishes. Unfortunately, some fishing practices are affecting the food of the dolphins adversely.

 

WWF has been at the forefront of community based approaches to save these aquatic animals by motivating local people through education and awareness programmes for rural communities. Public meetings are arranged, initially through building relationships with village elders. During such meetings, local people are provided with comprehensive information about the river and the value of aquatic ecosystems in general. Young volunteers are trained and given responsibilities to organize street plays, storytelling, slide shows and film shows in the local language.

Smaller species often ignored
“Local communities are catered to in this conservation programme since they are dependent on aquatic resources. Saving the river is dependent on saving this animal and vice versa. However, conservation efforts have been so concentrated on large charismatic megafauna like Tiger, Rhino, and Elephants that animals like Dolphins, Gharials and Turtles get scant attention, “states Dr Parikshit Gautam, Director of Wetlands, WWF India.

Considerable emphasis has been paid all along on the religious symbolism of the Ganga and the river dolphin. Local bodies to save the Ganga have been created and restrictions imposed on the use of plastics along the river at Narora. Tree plantation along the river bank has also been undertaken along with low cost sewage treatment structures and distribution of awareness material on dolphins and turtles.

WWF research indicates that although dolphin populations may be increasing in some areas, monitoring needs to be continued throughout the dolphin’s range. Human activities like agriculture and sand mining have to be controlled in the dolphin’s habitat to save the species from extinction. Reduction of pollution and availability of continuous flow in rivers are the quintessential requirements of good dolphin habitat. WWF partners the government in suggesting and promoting better schemes for riverine conservation and preservation of the Gangetic River Dolphin. Conservation of dolphins also leads to conservation of sympatric species such as gharial, turtles, otters and mugger crocodiles.

The Gangetic River Dolphin has been declared as India’s National Aquatic animal in 2009. Much needs to be done to ensure this icon of the Indian riverine ecosystem survives in the 21st century and greater public awareness generated about the intrinsic value of aquatic life to ensure that this beautiful animal is not solely dependent for survival on the charity of a few organizations and human beings.
Shubhobroto Ghosh is Programme Officer of TRAFFIC India.

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