Gangetic Dolphin Survey: 6,327 Counted Across River Systems
Why in the news
The first standardised assessment of Gangetic dolphins put the count at 6,327. The report was released by the Prime Minister at a National Board for Wildlife meeting in Gujarat.
Key facts
- Total: 6,327 Gangetic dolphins across the Ganga and Brahmaputra systems, over 8,507 km of river.
- Because earlier counts used varied methods, the figure is a baseline and cannot yet show population trends.
- Uttar Pradesh holds the most dolphins, followed by Bihar, West Bengal and Assam.
| River stretch | Dolphins |
|---|---|
| Ganga main stem | 3,275 |
| Ganga tributaries | 2,414 |
| Brahmaputra main stem | 584 |
| Brahmaputra tributaries | 412 |
| Beas River | 101 |
| Indus river dolphins | 3 |
Why counting is hard
- Dolphins stay underwater for long periods and surface only briefly to breathe.
- They have no striking marks to tell individuals apart, unlike stripes on tigers.
New method
- Acoustic hydrophones (underwater microphones) record echolocation clicks; observers triangulate positions so the same animal is not counted twice.
Threats
- Getting entangled in fishing nets is a leading cause of death.
- Studies continue on how pollution and habitat degradation affect survival.
Way forward
- The next survey comes after four years, using the same improved methods.
- The Prime Minister stressed community participation; compulsory school outreach will raise awareness of dolphin habitats.
Exam angle
- The dolphin is treated as an indicator of river ecosystem health.
- Survey tool: acoustic hydrophones.
- State with highest numbers: Uttar Pradesh.