The Ministry of Environment, Forest and Climate Change has started the second nationwide survey of riverine and estuarine dolphins under Project Dolphin, which for the first time will also estimate the Irrawaddy dolphin population in Odisha’s Chilika Lake and the Sundarbans. This biodiversity initiative is frequently discussed in GS-III environment classes at leading IAS coaching in Hyderabad institutes.
About the Species
- Scientific Name: Orcaella brevirostris
- A euryhaline dolphin – can survive in freshwater, brackish water, and seawater.
- Found in discontinuous populations near coasts, estuaries, and rivers of South and Southeast Asia.
Habitat and Distribution
- Present in three major rivers:
- Irrawaddy River (Myanmar)
- Mahakam River (Indonesia)
- Mekong River (Cambodia)
- In India: Mainly in Chilika Lake, Odisha, Also reported in the Sundarbans delta
- Prefer muddy, brackish waters at river mouths and deltas; rarely move far into the open sea.
Key Features
- Rounded head and face, no beak – resembles a baby beluga.
- Moveable lips and neck creases allow expressive facial movements.
- Grey body with lighter underside.
- Small dorsal fin; large flippers with curved edges; broad tail.
- Teeth are short, peg-like, and pointed (~1 cm long).
Conservation Status
- Listed as Endangered on the IUCN Red List.
- Major threats include habitat loss, pollution, accidental entanglement in fishing nets, and reduced prey availability.
Conservation status and threat analysis are key enrichment points for GS-III answers prepared through IAS coaching.
This topic is available in detail on our main website.
