Jan 11, 2021
Less famous than their marine cousins, river dolphins, are rapidly disappearing, along with their natural habitats. There are 5 species of river dolphins, plus two that frequent coastal waters and river estuaries. They live in large rivers such as the Ganges, the Hindu, the Yangtze, the Mekong and the Amazon River.
The Amazon River dolphin or Inia, also known as the pink dolphin or boto, lives in much of the Amazon and Orinoco River, in Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru and Venezuela. It is the most abundant freshwater cetacean, estimated to be tens of thousands.
The Yangtze River Dolphin or Baiji or Lipote was formally declared extinct in 2006 after scientists failed to find any individual of this species, which inhabits the great Chinese rivers.
The Ganges or Susu river dolphin can only live in fresh water and is essentially blind. They once lived throughout the Ganges-Brahmaputra-Meghna and Karnaphuli-Sangu river systems in Nepal, India and Bangladesh, from the foothills of the Himalayas to the Bay of Bengal. Today its population is fragmented by the numerous dams. The total population estimate is 1,200-1,800 individuals.
The Indus or Bhulan dolphin survives today with about 1,100 individuals in just 1,375 km of the Indus River, divided into populations isolated by six dams.
The pontoporia lives in the coastal waters of the Atlantic of southeastern South America; it lives mainly in shallow coastal waters, it is the only freshwater “dolphin” to live in the sea.
There are also two other species which, although living in the sea and not being part of the “river dolphins” from a systematic point of view, frequent whole waters.
The orcella, also known as the “Irrawaddy” dolphin, lives both in the sea and in fresh water, in a few locations in South and Southeast Asia. There are three populations: one of about 70-100 individuals living in a 190 km stretch of the Mekong River (Laos, Cambodia), one of 33-50 individuals in a 420 km stretch of the Mahakam River (Indonesia) and one of 59 individuals in a 370 km stretch of the Ayeyarwady River (Myanmar). Furthermore, a very small number survive in Songkhla Lake (Thailand) and Chilka Lake (India).
The sotalia lives in both fresh and salt water, on the east coast of Central and South America, from the Brazilian coast to the Caribbean. It is also called “Tucuxi“.
River dolphins are endangered animals and are among the priority species for WWF.
Since 2005, WWF has been working in Asia and South America with the River Dolphin Initiative. The authorities and ministries, local non-governmental organizations, fishermen, industry, communities and local schools collaborate in the protection activities of the WWF. Through the national offices and program offices of the WWF International, efforts are being made to increase public awareness in support of conservation projects on the Ganges River and in other basins of the world where these species live.
In India, WWF has developed a conservation plan for the Ganges River dolphin since 1997 with the aim of limiting habitat loss and degradation, illegal fishing and bycatch. To mitigate the threats, WWF encourages local communities along a 164 km stretch of the upper Ganges to use natural fertilizers, not to throw drains into the river, and to improve sewage systems. WWF is also working to rebuild the forest cover on the banks. In Nepal, WWF has started a project on the Karnali River population and its tributaries. The project analyzes threats to the Ganges dolphin and its habitat and provides solutions for local governments. At the same time, awareness-raising activities are being developed towards local populations. WWF is also conducting a series of large-scale initiatives and projects to ensure that the benefits produced by dams for human populations do not have negative impacts on the environment. The implementation of integrated water basin management plans are aimed at maintaining and restoring the naturalness of river ecosystems and promoting the sustainable use of water resources.
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