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| Last Updated:: 04/07/2019

Gangetic dolphins found in Bihar’s Mahananda river






A population of endangered Gangetic river dolphins has been found for the first time in the Mahananda river, a tributary of the Ganga, in Bihar’s Kishanganj district. A team of scientists from Vikramshila Biodiversity Research and Education Centre (VBREC) of Tilka Manjhi Bhagalpur University, spotted the 14 Gangetic river dolphins during a survey.





“Never before had any survey been conducted to search for dolphins in the Mahananda in Bihar. It is a positive development that dolphins were found in the first survey itself,” Sunil Choudhary, director of VBREC told Down To Earth.




There was secondary information that dolphins had been spotted in the Mahananda in neighbouring Araria district during monsoon floods, said Choudhary. Environmental activist Sudan Sahay had reported this long ago. The survey team spotted seven adult dolphins and seven calves. No juvenile was spotted.




Demand for water from the river has been increasing with the rise in temperature. “We need more water. As a result, water level is declining in the river, putting more pressure on the dolphins to manage their life cycle,” said Sinha.



Experts agree the Gangetic dolphins' habitats face serious threats from climate change. They point that increasing pollution due to largescale discharge of industrial and municipal waste, siltation, and mechanised boats pose the biggest threat to these freshwater dolphins.




The Gangetic river dolphin is India's national aquatic animal but frequently falls prey to poachers. Their carcasses are found regularly on river banks. Gangetic river dolphins fall under Schedule I of the Indian Wild Life (Protection) Act and have been declared an endangered species by the International Union for Conservation of Nature (IUCN).




The Gangetic river dolphin is one of the four freshwater dolphin species in the world. The other three are found in the Yangtze river in China, the Indus river in Pakistan and the Amazon river in South America. The Gangetic river species — found in India, Bangladesh and Nepal — is blind and finds its way and prey in the river waters through echoes. These dolphins live by echolocation and sound is everything to them. They navigate, feed, escape danger, find mates, breed, and nurse babies by echolocation.