IN NEWS: Vikramshila Gangetic Dolphin Sanctuary and Riverine Conservation in Bihar

ANALYSIS

Introduction

The Vikramshila Gangetic Dolphin Sanctuary (VGDS), located along the Ganga River in Bihar, has emerged as a critical refuge for the endangered Ganges river dolphin. Spread across a 60 km stretch from Sultanganj to Kahalgaon, the sanctuary represents one of the last viable habitats for these “blind swimmers” and reflects the ecological richness as well as vulnerability of India’s riverine ecosystems.

Ecological Significance and Biodiversity Profile

The sanctuary is not merely a dolphin habitat but a multi-species riverine ecosystem. It supports a wide range of fauna, indicating high ecological productivity and habitat suitability.

• It is recognised as an Important Bird Area (IBA) by the Bombay Natural History Society
• Hosts diverse species such as:
  • Indian skimmer
  • Pallas’s fish eagle
  • Greater and lesser spotted eagles
  • Gharials and freshwater turtles
• The stretch between Sultanganj and Bhagalpur (~36 km) acts as a breeding ground for birds, especially during monsoon due to formation of sandbars

This highlights the interconnectedness of aquatic and avian biodiversity.

Population Indicators and Habitat Health

Field observations suggest that more than 250 dolphins along with calves are sighted near Bhagalpur (Jahnvi Ghat region). This is a significant ecological indicator:

• Suggests relatively clean water conditions
• Indicates successful breeding population
• Reflects effectiveness of local conservation efforts

Thus, dolphin presence acts as a bio-indicator of river health.

Dynamic River System and Habitat Characteristics

The VGDS is characterised by a dynamic fluvial system:

• During monsoon, the Ganga’s meandering channels and floodplains shift
• Creation of seasonal sandbars, which act as:
  • Nesting grounds for birds
  • Microhabitats for aquatic organisms

This dynamic nature enhances biodiversity but also makes conservation planning complex.

Threats and Conservation Challenges

Despite its ecological richness, the sanctuary faces multiple anthropogenic pressures:

• Pollution:
  • Agricultural runoff (fertilisers, pesticides)
  • Industrial and domestic effluents
• Hydrological disruptions:
  • Dams, bridges, irrigation projects affecting flow and migration
• Fishing-related threats:
  • Entanglement in gill nets
  • Accidental killings and poaching

These threats disturb the delicate ecological balance and directly impact dolphin survival.

Role of Community and Governance

The conservation success in VGDS is partly attributed to:

• Local community awareness and participation
• Efforts by:
  • Government authorities
  • Environmental experts and institutions
• Increasing emphasis on citizen responsibility in conservation

This reflects a bottom-up conservation model, essential for long-term sustainability.

Way Forward

To ensure sustainable conservation of the sanctuary, a multi-pronged strategy is required:

• Strengthening pollution control mechanisms
• Promoting sustainable fishing practices
• Enhancing scientific monitoring and census techniques
• Integrating VGDS into national river conservation programmes
• Encouraging eco-tourism with ecological safeguards
• Focus on habitat restoration and maintaining ecological flow (e-flow)

Conclusion

The Vikramshila Gangetic Dolphin Sanctuary stands as a symbol of both hope and challenge in India’s environmental governance. While it demonstrates that biodiversity can thrive with proper protection and community engagement, persistent anthropogenic pressures necessitate continuous scientific intervention and policy support to secure the future of the Gangetic dolphin.

STATIC PART

1. Bombay Natural History Society (BNHS)

Basic Profile

• Established: 15 September 1883
• Headquarters: Hornbill House, Mumbai
• Type: Non-governmental organisation (NGO)
• Nature: One of the oldest and largest biodiversity research organisations in India

Functions and Role

• Works for conservation of biodiversitythrough:
  • Scientific research
  • Education and awareness
  • Policy advocacy
• Publishes:
  • Journal of the Bombay Natural History Society
• Conducts:
  • Wildlife surveys and bird counts
  • Asian Waterbird Census (India participation)
• Recognised as:
  • Scientific and Industrial Research Organisation (SIRO) by Govt. of India
• Partner of:
  • BirdLife International (India)

Key Contributions

• Identification of Important Bird Areas (IBA)
• Contribution to species discovery and taxonomy
• Support in wildlife crime investigation (species identification)
• Major role in shaping India’s conservation science tradition

2. Meandering Rivers of Bihar and India

Concept: Meandering Rivers

• A meandering river is one that flows in curved, sinuous loopsdue to:
  • Low gradient (gentle slope)
  • High sediment load
  • Lateral erosion and deposition

Key Features

• Formation of:
  • Meanders (loops)
  • Oxbow lakes
  • Floodplains
  • Point bars and cut banks
• Dynamic nature:
  • River constantly changes course over time

Meandering Rivers in Bihar

Bihar’s rivers are classic examples due to alluvial plains of the Ganga basin:

• Ganga River
• Kosi River (called “Sorrow of Bihar” due to shifting course)
• Gandak River
• Bagmati River

Characteristics in Bihar context:

• Frequent course shifting and flooding
• Creation of fertile alluvial soil
• Formation of sandbars (diara land)
• Important for wetlands and biodiversity (including dolphins)

Meandering Rivers in India (General)

• Prominent in:
  • Indo-Gangetic plains
  • Brahmaputra valley
• Examples:
  • Brahmaputra River (highly dynamic)
  • Yamuna River
• Importance:
  • Supports agriculture
  • Creates rich ecosystems
  • However, leads to:
    • Flood hazards
    • Riverbank erosion

Major Meandering Rivers of North Bihar (Origin → Confluence)

North Bihar rivers are highly meandering due to low gradient, heavy Himalayan silt load, and wide alluvial floodplains, leading to frequent flooding and course shifting.

Major Rivers Table

Supplement: Oxbow Lakes in Bihar

Concept Table: Meandering vs Oxbow Lake

3. Vikramshila Gangetic Dolphin Sanctuary (VGDS)

Basic Profile

• Established: 1991
• Location: Bihar
• River Stretch: Along Ganga River
• Extent: ~60 km (Sultanganj to Kahalgaon)

Ecological Significance

• India’s only dedicated dolphin sanctuary
• Protects:
  • Gangetic river dolphin (National Aquatic Animal)
• Recognised as:
  • Important Bird Area (IBA) (by BNHS)

Biodiversity Profile

• Aquatic fauna:
  • Gangetic dolphins
  • Gharials
  • Freshwater turtles
• Avifauna:
  • Indian skimmer
  • Pallas’s fish eagle
  • Migratory birds
• Rich riverine ecosystem with sandbars and wetlands

Key Features

• Located in dynamic meandering stretch of Ganga
• Seasonal:
  • Floodplains and sandbars formation
• Acts as:
  • Breeding ground for birds
  • Critical habitat for dolphins

Conservation Importance

• Acts as a last stronghold for endangered dolphins in eastern India
• Indicator of:
  • River health and water quality
• Supports:
  • Community-based conservation models

Threats

• Pollution:
  • Agricultural runoff
  • Industrial waste
• Hydrological changes:
  • Dams, irrigation projects
• Fishing-related mortality:
  • Net entanglement
• Habitat disturbance due to:
  • Human activities

Updated - 15 June 2025 | 05:14 AM IST | News Source: TOI