Scientific Name: Platanista gangetica
Also known as South Asian River Dolphin , Indian River Dolphin , Blind River Dolphin in English ; Susu , Sus , Souns , Soon , Soons , Sunsar in Hindi ; Hihoo, Sihoo in Assamese ; Shushuk in Sanskrit ; Bhageerath in the Terai region of Bihar .
P. gangetica is historically distributed in major river systems (Ganges-Brahmaputra-Meghna and Karnaphuli-Sangu) of India, Nepal and Bangladesh. But currently, the species is restricted to stretches in India’s Ganga-Brahmaputra-Barak river system, Nepal’s Karnali, Sapta Koshi and Narayani river systems, and Bangladesh’s Meghna, Karnaphuli and Sangu river systems.
Geographical Distribution

The distribution range of the Ganges River dolphins in India covers seven states, namely, Assam, Uttar Pradesh, Madhya Pradesh, Rajasthan, Bihar, Jharkhand, and West Bengal.
Characteristics
- The Gangetic dolphins can only live in freshwater.
- They are essentially blind, their eyes are rudimentary, and the function of the eyes is taken over by Sonar mechanisms.
- Ultrasonic auditory sense organs enable them to produce and receive sound.
- Highly developed acoustic sense aids in food capture, navigation and reproduction
- Females are larger than males in size, beak is longer in females than in males.
- It prefers deep waters, in and around the confluence of rivers.
- Unlike other marine dolphins, Ganges River dolphins do not stay underwater for a long time due to low concentration of myoglobin, usually stay underwater for 30-60 seconds and come to the surface for breathing.
- They are not gregarious, usually solitary.
- Unique sleeping behaviour termed as ‘polyphasic micro sleep’ (not more than eight seconds) roughly translates into 7-8 hours in a day .
- The breeding season of the Gangetic Dolphin extends from January to June, and only a single calf is born after a gestation period of about 9 months to 11 months.
- They are catholic feeders and feed on several species of fish, invertebrates, and possibly turtles and birds.
- The dolphin has the peculiarity of swimming on one side so that its flipper trails the muddy bottom. This behaviour is understood to help it find food.
- The species has been declared the ‘National Aquatic Animal’ by the Government of India, and is part of our national heritage.

The important steps taken by the Government for the conservation of the Gangetic river dolphin include:
- The Gangetic river dolphin is listed in Schedule I of the Wildlife (Protection) Act, 1972, according to the highest degree of protection.
- The Gangetic river dolphin has been designated as the National aquatic Animal of India.
- The Ministry has included the Gangetic river dolphin as one of the 22 critically endangered species for providing financial assistance to States under the Centrally sponsored scheme ‘Development of Wildlife habitats’.
- Important habitats of Gangetic river dolphin along the Ganges River have been notified as Protected Areas, such as Vikramshila Dolphin Sanctuary, Bihar.
- A comprehensive action plan (2022-2047) has been developed to ensure well well-being of the river dolphin and aquatic habitats.
This species has been included in Schedule I of the Indian Wildlife (Protection) Act 1972 (which means that hunting, trade or harming this animal attracts harsh punishments) , in Appendix I of the Convention on International Trade in Endangered Species (CITES), in Appendix II of the Convention on Migratory Species (CMS) and categorised as Endangered on the International Union for the Conservation of Nature (IUCN) Red List.