IN NEWS: First Estimate of Gangetic Dolphins in India

ANALYSIS

Introduction

A first-of-its-kind national estimate of the Ganges river dolphin population has been released by the Ministry of Environment, Forest and Climate Change on the occasion of World Wildlife Day.

The report estimates a total of 6,327 dolphins, including 6,324 Ganges river dolphins and 3 Indus river dolphins, marking a significant step in establishing a baseline dataset for conservation.

The survey, conducted under Project Dolphin launched in 2020, gives the first-ever glimpse into the species’ status in India.

India is home to two species of freshwater dolphins — Ganges (Platanista gangetica) and Indus (Platanista minor), which serve as bio-indicators of healthy river ecosystems.

Both dolphins are classified as Endangered and listed as Schedule I species under the provisions of the Wild Life (Protection) Act, 1972.

Key Findings of the Survey

• Total population: 6,327 dolphins
• Species breakup:
  • 6,324 Ganges river dolphins
  • 3 Indus river dolphins
• River-wise distribution:
  • Ganga main stem: 3,275
  • Ganga tributaries: 2,414
  • Brahmaputra main stream: 584
  • Brahmaputra tributaries: 51
  • Beas river: 3
• Survey covered a cumulative 8,507 km river stretch

• Conducted across:
  • 28 rivers
  • 8 states
  • 8,507 km river stretch
• Species distribution:
  • Majority are Ganges river dolphins
  • Only 3 Indus dolphins recorded (in Beas river)
• Ecological observation:
  • Dolphins prefer confluences, meanders, and mid-channel islands
• Historical trend:
  • Population declined from 4,000–5,000 (late 20th century) to ~1,800, now showing recovery

Geographical Distribution

• Highest population in:
  1. Uttar Pradesh – 2,397
  2. Bihar – 2,220
  3. West Bengal – 815
• Other states:
  • Assam – 635
  • Jharkhand – 162
  • Rajasthan & Madhya Pradesh – 95
  • Punjab – 3 (lowest; Indus dolphins in Beas)

Inference: Distribution concentrated in Ganga-Brahmaputra basin, highlighting its ecological importance.

• Highest population recorded in:
  1. Uttar Pradesh
  2. Bihar
  3. West Bengal
  4. Assam

This reflects the ecological importance of the Ganga-Brahmaputra river system as a habitat for freshwater biodiversity.

Survey Methodology

• Survey initiated in 2021
• Conducted using:
  • Boat-based surveys at constant speed
  • Acoustic hydrophones (underwater microphones)
• Dolphins detected through:
  • Echolocation signals
  • Triangulation technique using multiple observers
• Special precautions taken to avoid double counting
• Dolphins are functionally blind and rely on sound for navigation

Significance of the Study

• First standardised national-level population estimate
• Provides a scientific baseline for future monitoring
• Helps identify critical habitats and conservation zones
• Strengthens India’s commitment to aquatic biodiversity conservation
• Enhances policy support under river conservation initiatives

Limitations of the Estimate

• Earlier studies used non-uniform methodologies
• Current estimate cannot indicate population trends
• Lack of historical comparability limits long-term analysis
• High dependence on technical expertise and training

Conservation Context

• The Ganges river dolphin is:
  • India’s National Aquatic Animal
  • An indicator of river ecosystem health
• Major threats:
  • Entanglement in fishing nets
  • River pollution
  • Habitat fragmentation (dams, barrages)
• Ongoing studies are assessing impact of pollution on habitat

Way Forward

• Conduct periodic surveys (next expected in ~4 years)
• Strengthen capacity building and technical training
• Reduce fishing-related mortality
• Enhance pollution control measures
• Promote community participation and awareness, especially among students
• Integrate conservation with flagship programmes like river rejuvenation missions

Conclusion

The first-ever estimate of Gangetic dolphins marks a crucial milestone in India’s conservation framework. While it does not yet provide insights into population trends, it lays the groundwork for evidence-based policy formulation and long-term ecological monitoring.

STATIC PART

Ministry of Environment, Forest and Climate Change (MoEFCC)

• Established: 1985
• Headquarters: New Delhi
• Present Minister: Bhupender Yadav
• Functions:
  • Formulation of environmental policies and laws
  • Implementation of wildlife conservation programmes
  • Coordination of climate change actions
  • Protection of forests and biodiversity

Updated - 03 March 2025 | 11:02 pm IST | News Source: The Hindu