Gangetic Dolphin Population Estimate

The first-ever estimate of Gangetic dolphins, the only riverine dolphins in India, has identified a total of 6,327 individuals in the river Ganga and its tributaries.

Key Findings

• Out of the total, 6,324 are Ganges river dolphins and 3 are Indus river dolphins.
• The distribution includes: 
  • 3,275 dolphins in the main stem of the Ganga.
  • 2,414 in Ganga tributaries.
  • 584 in the Brahmaputra mainstream.
  • 412 in Brahmaputra tributaries.
  • 101 in the river Beas.
• The survey spanned a cumulative distance of 8,507 km.
• The maximum number of dolphins were reported in Uttar Pradesh, followed by Bihar, West Bengal, and Assam.

Survey Methodology

• Unlike land animals, counting dolphins poses unique challenges as they are underwater and surface sporadically.
• The survey used acoustic hydrophones and two sets of observers to estimate dolphin presence and avoid double counting.
• Challenges include dolphins getting entangled in fishermen's nets and the impact of pollution on their habitat.

Future Directions

• The survey is expected to be repeated in four years.
• Conservation efforts are emphasized, including the involvement of local populations and encouraging school children to visit dolphin habitats.