From UPSC perspective, the following things are important :
Prelims level : Gangetic and Indus Dolphin
Mains level : Not Much
Detailed analysis of South Asian river dolphins has revealed that the Indus and Ganges River dolphins are not one, but two separate species.
About Gangetic Dolphin
- The Gangetic river system is home to a vast variety of aquatic life, including the Gangetic dolphin (Platanista gangetica).
- It is one of five species of river dolphin found around the world.
- It is found mainly in the Indian subcontinent, particularly in Ganga-Brahmaputra-Meghna and Karnaphuli-Sangu river systems.
- An adult dolphin could weigh between 70 kg and 90 kg. The breeding season of the Gangetic dolphin extends from January to June.
- They feed on several species of fishes, invertebrates etc.
Indus Dolphin is the divergent specie
- Currently, they are classified as two subspecies under Platanista gangetica. The study estimates that Indus and Ganges river dolphins may have diverged around 550,000 years ago.
- The international team studied body growth, skull morphology, tooth counts, colouration and genetic makeup and published the findings last month in Marine Mammal Science.
- The Indus and Ganges River dolphins are both classified as ‘Endangered’ species by the International Union for Conservation of Nature (IUCN).
- It is the national aquatic animal and had been granted non-human personhood status by the government in 2017.
- It is also protected under Schedule I of the Wildlife Protection Act (1972).
- Vikramshila Gangetic Dolphin Sanctuary (VGDS) in Bihar is India’s only sanctuary for the Gangetic dolphin.
- It has been categorised as endangered on the Red List of Threatened Species by the IUCN
- Physical barriers such as dams and barrages created across the river, the declining river flows reduced the gene flow to a great extent making the species vulnerable.