Source: Science Reporter, Vol. 63, No. 03, March 2026 | CSIR-NISCPR
The Ganges River Dolphin (Platanista gangetica) — India’s National Aquatic Animal — is one of only four freshwater dolphin species in the world. Once abundant across the subcontinent’s river networks, it now faces existential threats. A 2025 population census brings both hope and urgency.
Taxonomic and Biological Profile
| Parameter | Detail |
|---|---|
| Scientific name | Platanista gangetica |
| Common names | South Asian River Dolphin; Susu (Ganga); Bhulan (Indus) |
| Family | Platanistidae |
| Subspecies | P. g. gangetica (Ganges-Brahmaputra); P. g. minor (Indus — Pakistan) |
| National status | Schedule I, Wildlife (Protection) Act, 1972 |
| IUCN status | Endangered |
| CITES | Appendix I (no commercial trade permitted) |
| CMS | Appendix II (conservation cooperation needed) |
| National Aquatic Animal | Declared 2009 |
Population Census 2025: Key Numbers
A comprehensive population survey coordinated by the Wildlife Institute of India (WII) and Ministry of Environment, Forest & Climate Change (MoEFCC) assessed the full range:
| River System | Population |
|---|---|
| Mainstream Ganges | 3,275 |
| Ganges tributaries | 2,414 |
| Brahmaputra mainstream | 584 |
| Brahmaputra tributaries | 51 |
| TOTAL (India) | 6,324 |
This represents an improvement from earlier estimates and suggests that conservation measures are beginning to stabilise populations in some stretches.
Unique Biology: Why “One of a Kind”
1. Functional Blindness:
- Ganges Dolphins are effectively blind — their eyes lack a crystalline lens
- They navigate entirely through echolocation (biosonar) — emitting clicks and interpreting returning echoes
- This makes them highly sensitive to underwater noise pollution (boat motors, sonar)
2. Obligate Freshwater Habitat:
- Unlike marine dolphins, Platanista is strictly freshwater — cannot survive in saline or brackish water
- Confined to the Ganges-Brahmaputra-Meghna and Karnaphuli-Sangu river systems
3. Indicator Species:
- Acts as a flagship and umbrella species for Gangetic ecosystem health
- Presence indicates clean water, healthy fish stocks, and good river flow
- Their decline signals broader river ecosystem degradation
Key Threats
| Threat | Mechanism |
|---|---|
| Dam construction | Fragmentates habitat; prevents seasonal migration; alters flow regime |
| Fishing net entanglement | Accidental bycatch — major mortality source |
| River pollution | Industrial effluents, agricultural runoff, sewage reduce fish prey base |
| Sand mining | Destroys riverbed habitat; increases siltation |
| Boat traffic | Propeller injuries; noise disrupts echolocation |
| Climate change | Altered monsoon patterns; reduced river discharge |
Project Dolphin (2020–present)
Announced by PM Narendra Modi on Independence Day 2020 (August 15) — modelled on the success of Project Tiger:
| Component | Details |
|---|---|
| Coverage | Both river dolphins (Gangetic) and marine dolphins (Irrawaddy, Humpback) |
| Nodal ministry | MoEFCC |
| Key partners | WII Dehradun, state forest departments, fishing communities |
| Community role | Dolphin Mitra programme — local fishermen as conservation monitors |
| Population monitoring | Annual surveys; photo-ID cataloguing; first satellite tagging in Assam (WII, 2025) |
| Habitat protection | Dolphin Sanctuaries — Vikramshila in Bihar is India’s only dedicated dolphin sanctuary |
Vikramshila Gangetic Dolphin Sanctuary, Bihar:
- 50 km stretch of Ganges between Sultanganj and Kahalgaon
- Established 1991
- Highest dolphin density in India
UPSC Relevance
GS3 — Environment & Ecology:
- Freshwater biodiversity conservation
- Indicator species and their role in environmental monitoring
- Flagship species vs. umbrella species vs. keystone species distinction
- Project Dolphin as a conservation model (compare with Project Tiger, Project Elephant, Project Snow Leopard)
GS2 — International Relations:
- CITES Appendix I: legal obligations on trade and trafficking
- CMS (Bonn Convention): India’s obligations for migratory species — relevant because Gangetic dolphins undertake seasonal migrations within river systems
- Indus Dolphin (P. g. minor): conservation co-operation opportunity with Pakistan
Key Distinctions:
- Platanista gangetica (Ganges Dolphin, India) ≠ Amazon River Dolphin (Inia geoffrensis) ≠ Irrawaddy Dolphin (Orcaella brevirostris, found in Chilika Lake and Odisha coast)
- Gangetic Dolphin: blind (echolocation only); Irrawaddy Dolphin: has functional eyesight
Facts Corner
- Scientific name: Platanista gangetica | Family: Platanistidae
- IUCN: Endangered | CITES: Appendix I | Schedule I WPA 1972
- India population (2025): 6,324 (WII census)
- Unique trait: functionally blind — navigates by echolocation
- National Aquatic Animal: since 2009
- Project Dolphin: launched August 15, 2020 (Independence Day)
- Vikramshila Sanctuary (Bihar): India’s only dedicated dolphin sanctuary; 50 km Ganges stretch
- First satellite tagging: Assam, 2025 — by WII, MoEFCC
