Ganges River Dolphin

Ganges River Dolphin

#GS-03 Environment and Ecology

For Prelims:

About Ganges River Dolphin:

  • The Ganges River dolphin (Platanista gangetica) was officially discovered in 1801.
  • It is also known by the name susu (popular name) or “Sisu” (Assamese language) and shushuk (Bengali).
  • Ganges river dolphins once lived in the Ganga-Brahmaputra-Meghna and Karnaphuli-Sangu river systems of Nepal, India, and Bangladesh.
  • But the species is extinct from most of its early distribution ranges.
  • The Ganges River dolphin can only live in freshwater and is essentially blind.
  • They hunt by emitting ultrasonic sounds, which bounces off of fish and other prey, giving them an ability similar to sonar or Bats.
  • They are frequently found alone or in small groups, and generally a mother and calf travel together.
  • Calves are chocolate brown at birth and then have grey-brown smooth, hairless skin as adults.
  • Females are larger than males and give birth once every two to three years to only one calf.
  • The Ganges river dolphin is important because it is a reliable indicator of the health of the entire river ecosystem.
  • The government of India declared it the National Aquatic Animal in 2009 and it is the official animal of the Indian city of Guwahati.

Other Facts about Ganges River Dolphin:

  • IUCN Status: Endangered.
  • CITES Appendix I.
  • Wildlife (Protection) Act 1972: Schedule 1
  • The Vikramshila Gangetic Dolphin Sanctuary in Bihar is the only sanctuary for the conservation of Gangetic dolphins in India.

For Mains:

The major threats to Ganges River Dolphins:

  • The Ganges river dolphin is still hunted for meat and oil, which are both used medicinally.
  • Industrial, agricultural, and human pollution is another serious cause of habitat degradation.
  • Each year, 9,000 tons of pesticides and 6 million tons of fertilizers are used in the vicinity of the river.
  • High levels of pollution can directly kill prey species and dolphins, and completely destroy their habitat.
  • As the top predator, river dolphins have been known to have high levels of persistent toxic chemicals in their bodies, which is likely to adversely affect their health.