Sundarban National Park: UNESCO World Heritage Site – Complete Conservation Outlook (2017 Assessment)

Introduction

The Sundarban National Park, inscribed as a UNESCO World Heritage Site in 1987, represents one of the most extraordinary natural wonders on Earth. Located in the Ganges delta, this vast wilderness spans across India and Bangladesh, containing the world's largest area of mangrove forests. The IUCN Conservation Outlook Assessment 2017 provides a comprehensive evaluation of this remarkable site, examining its values, threats, and management effectiveness.

This article presents a detailed analysis of the Sundarban National Park based on the official IUCN assessment, offering insights into its current state, challenges, and future prospects for conservation.

SITE INFORMATION AT A GLANCE

OVERALL CONSERVATION OUTLOOK: GOOD WITH SOME CONCERNS

The IUCN assessment classifies the Sundarban National Park's conservation outlook as "Good with some concerns" as of November 2017. This rating reflects a balanced picture of effective management alongside significant ongoing threats.

Key Assessment Summary

Assessment Highlights

"The values of the Sundarbans National Park remain in good condition overall, and the management of the site is largely effective. However, the site is threatened by multiple on-going threats from both within and external to the site."

The assessment notes that while biodiversity values (rare and threatened mammals, birds, and reptiles) are largely stable, degradation of floral diversity and ongoing ecological processes has been, and continues to be, a major issue.

WORLD HERITAGE VALUES: WHAT MAKES SUNDARBAN SPECIAL?

The Sundarban National Park was inscribed on the UNESCO World Heritage List for meeting two critical criteria: (ix) and (x).

Criterion (ix): The Largest Mangrove Forest in the World

The wider Sundarbans, which includes the Sundarban National Park, represents the largest area of mangrove forest in the world and is the only mangrove habitat inhabited by the tiger.

Key Ecological Processes:

Criterion (x): Rare and Threatened Species

The Sundarbans provides the only remaining habitat in the lower Bengal Basin for many faunal species. The site supports an extraordinary array of globally threatened species across multiple taxonomic groups.

Mammals: 31 Documented Species

Tiger Population Estimate (2014): 62-96 individuals (Jhala et al., 2015)

Birds: Over 300 Species Recorded

The Sundarbans supports a varied and colourful birdlife with exceptional diversity for a mangrove ecosystem.

Globally Threatened Bird Species:

Reptiles: 59 Documented Species

The site has a diverse herpetofauna with an exceptional number of threatened reptiles.

Flora: Rich Mangrove Diversity

The mangrove ecosystem of the Sundarbans is considered unique because of its immensely rich mangrove flora.

THREATS ASSESSMENT: HIGH THREAT

The IUCN assessment categorizes the overall threats to Sundarban National Park as "High Threat", reflecting the multiple pressures facing this fragile ecosystem.

Current Threats Summary

Detailed Threat Analysis

1. Hydrological Alterations (Very High Threat)

The eastward migration of the Ganges, combined with upstream water diversion (up to 40% of dry season flow diverted by Farraka Barrage since 1974), has resulted in:

• Reduced freshwater flushing of the Sundarbans

• Increased saline intrusion, particularly in dry season

• Soil acidification from reclamation

• Increased siltation, requiring dredging for navigation

• Long-term ecological change throughout the ecosystem

2. Climate Change and Sea Level Rise (Very High Threat)

The Sundarbans forest sits at low elevation (maximum ~7m above sea level), making it extremely vulnerable to sea level rise.

Alarming Statistics:

IPCC Projection (2013): A 45cm rise in sea level is likely by the end of the 21st century.

Ecological Consequences:

• Submersion of large portions of the forest

• Increased salinity driving ecological succession to more salt-tolerant species

• Loss of Sundri trees to Gewa (Excoecaria agallocha)

• Reduced mangrove biodiversity

• Loss of habitat for threatened species

• Increased incidence of top-dying disease in Sundri trees

"There has already been an increase in the proportion of salt tolerant species Avicennia marina and A. alba during the last three decades from less than 1% to >8% in the Sundarbans National Park." (Sanyal, 2012)

3. Extreme Weather Events (High Threat)

Cyclones and tidal waves cause significant damage to the forest and wildlife:

• 2007 Cyclone Sidr: 6.5m storm surge along 100km coast, 3,500+ lives lost, 40% of World Heritage site seriously damaged

• Recovery Time: 10-15 years for ecosystem regeneration (if poaching and intrusions do not jeopardize recovery)

4. Top-dying Disease in Sundri Trees (High Threat)

The disease affecting dominant Sundri trees (Heritiera fomes - Endangered) is causing significant die-back:

• Incidence increases with increasing salinity

• Infected trees are replaced by common Gewa (Excoecaria agallocha)

• Forest structure becoming simpler

• Mean forest height decreasing

• Habitat quality for arboreal mammals and birds reduced

• Approximately 70% of Sundri stems estimated to be moderately or severely affected

• Extent of pure Sundri stands decreased by 21% since 1926

5. Poaching and Illegal Wildlife Trade (Data Deficient)

Tiger poaching remains a significant concern:

• At least 17 seizures of tiger skins and body parts in areas around Sundarbans (2000-2010)

• High value of tiger products on illegal markets provides strong incentive

• True level of illegal hunting unknown and unquantified

6. Aquaculture Encroachment (High Threat)

Illegal shrimp/prawn farms continue to encroach into the Tiger Reserve:

• Clearing of forest areas for pond creation

• Sources of solid and waste pollution

• Illegal trapping and hunting of forest vertebrates

• Dragnets deplete tiger prawn populations and juveniles of many species

• Erosion of banks and mudflats

• Prevention of mangrove seedling establishment

7. Fishing and Bycatch (High Threat)

Shrimp and prawn fry harvesting is extremely destructive:

• Gillnets cause entanglement of threatened aquatic mammals (Ganges River dolphin, Irrawaddy dolphin) and turtles

• Depletion of fisheries resources

• Knock-on effects throughout food chain

PROTECTION AND MANAGEMENT: MOSTLY EFFECTIVE

The IUCN assessment rates the overall protection and management of Sundarban National Park as "Mostly Effective", highlighting numerous best practices while identifying areas needing improvement.

Management Effectiveness Ratings

Key Management Strengths

1. Community Participation (Highly Effective)

The West Bengal Ministry of Environment and Forests and Project Tiger work directly with local communities through:

Community Benefits:

• Assistance in irrigation and water infrastructure

• Jetty construction

• Advice on fishing and aquaculture

• Medical clinics

• Training and employment as tourist guides

• Alternative livelihood generation

"Participatory governance and alternative livelihood generation activities have been very successful in reducing antagonism between local communities and the management agencies and maintaining the Outstanding Universal Value of the site."

2. Human-Wildlife Conflict Mitigation (Best Practice)

Innovative approaches to reduce tiger-human conflict include:

• Nylon net fencing along forest boundaries

• Encouraging villagers to drive tigers back into forests rather than killing them

• Relocation of problem tigers

• Introduction of electrified human models

• Face masks for backs of villagers' heads (to prevent tiger attacks from behind)

3. Staff Training and Development (Mostly Effective)

Based on a Training Need Assessment, 13 areas for necessary staff training were identified:

4. Education and Outreach (Mostly Effective)

Project Tiger and the Forest Department have developed an important Outreach programme targeting:

• School and college students

• Government departments

• Corporate offices

• Police and military personnel

Facilities: Mangrove Interpretation Centre at Sajnekhali Tourist Lodge

5. Tourism Management (Mostly Effective)

Tourism Infrastructure:

• Watchtowers at Sajnakhali Wildlife Sanctuary, Sudhanyakhali, Haldi, and Netidhopani

• Sundarban Tiger Camp at Dayapur, Gosaba

• Overnight facilities on sightseeing boats

Areas Needing Improvement

1. Monitoring (Some Concern)

Gaps Identified:

• Insufficient monitoring of most mammal populations

• Limited monitoring of aquatic mammals

• Need for consistent tiger monitoring methodologies

• Lack of coordination with Bangladesh for metapopulation assessment

• Need for thorough monitoring of hydrological changes

Positive Note: Recent tiger population estimates (2014) using camera trap-based capture-recapture methods estimated 62-96 individuals.

2. Research (Some Concern)

Gaps Identified:

• Information not compiled and made available to decision-makers

• Little work on ecological resilience, particularly regarding climate change

• Need for assessment of appropriate indicators for monitoring trends in resilience

3. Boundaries and Transboundary Cooperation (Some Concern)

Issues:

• Significant human pressure within buffer zone

• Increasing population pressure may infringe upon World Heritage site

• Lack of formal transboundary management with Bangladesh Sundarbans

Recommendation: Establishment of a transboundary site, managed jointly with the Sundarbans, Bangladesh World Heritage site, as previously discussed (UNESCO, 2001).

4. Sustainable Finance (Mostly Effective but Inadequate)

Issue: Funding not considered adequate to build capacity (financial and human) for effective management and protection of Outstanding Universal Value.

STATE AND TREND OF VALUES

Summary Assessment

Detailed Analysis by Value

The Largest Mangrove Forest in the World (High Concern, Deteriorating)

Despite remaining the largest continuous mangrove forest globally, the Sundarbans is now almost half the size of the area that existed in the late 1800s.

Key Degradation Factors:

• Eastward migration of Ganges River

• Upstream freshwater diversion (Farraka Barrage)

• Increased saline intrusion

• Soil acidification

• Coastal erosion and retreat (210.25 km² lost between 1969-2009)

• Reduced plant biomass production

• Altered siltation and sedimentation patterns

• Replacement of Sundri by Gewa due to top-dying disease

Rare and Threatened Mammals (Low Concern, Data Deficient)

Positive Indicators:

• Tiger population relatively stable (62-96 individuals)

• Ganges River dolphin and Irrawaddy dolphin populations appear stable

• Stronghold populations for several globally threatened species

Concerns:

• Eight globally threatened species locally extirpated over last century:

  • Javan rhinoceros (Rhinoceros sondaicus) - CR

  • Indian rhinoceros (Rhinoceros unicornis) - VU

  • Water buffalo (Bubalus bubalis) - EN

  • Swamp deer (Rucervus duvaucelii) - VU

  • Barking deer (Muntiacus muntjak) - EN

  • Gaur (Bos gaurus) - VU

  • Hog deer (Axis porcinus) - EN

  • Sambar (Rusa unicolor) - VU

• Ongoing threats from poaching, habitat loss, pollution, altered hydrology, and fishing entanglement

Rare and Threatened Reptiles (Low Concern, Data Deficient)

Promising Signs:

• Good management and breeding programmes

• Estuarine crocodile captive breeding at Bhagabatpur Crocodile Breeding Centre

• Olive ridley turtle rearing at Sajnakhali

• Northern river terrapin breeding program (Turtle Survival Alliance & West Bengal Forest Department) - successful hatching of several juveniles

Concerns:

• Estuarine crocodile population only ~100 individuals

• Species considered functionally extinct in Sundarbans (but recovery possible through breeding program)

Rare and Threatened Flora (Low Concern, Deteriorating)

Sundri Decline:

BENEFITS PROVIDED BY THE SITE

1. Carbon Sequestration (Global Significance)

Mangrove forests store enormous amounts of carbon, rivalling tropical rainforests. As the world's largest remaining mangrove forest, the Sundarbans provides huge carbon storage, with major climate change mitigation value globally.

2. Coastal Protection

The Sundarbans provides critical protection for inland areas and human populations from:

• Cyclones and storm damage

• Tidal surges

• Tsunamis

• Flooding

3. Soil Stabilisation

Mangrove trees trap sediment and organic matter, stabilizing sediments and reducing inputs into the Bay of Bengal.

4. Fisheries Conservation

The Sundarbans provides important spawning and nursery grounds for several fish species, including economically important species.

5. Pollination Services

Large numbers of honey-bees produce great quantities of honey and wax, providing livelihoods for local people and potentially pollinating local crops.

6. Outdoor Recreation and Tourism

With ~40,000 annual visitors (2002), tourism provides economic benefits and supports local communities through guide training and employment.

7. Research and Education

The site serves as a living laboratory for research on mangroves, climate change, biodiversity, and human-wildlife relationships.

CONSERVATION PROJECTS (ACTIVE AS OF 2017)

KEY RECOMMENDATIONS FROM IUCN ASSESSMENT

For Threat Mitigation

1. Climate Change Adaptation: Develop and refine effective management action based on studies of site resilience under predicted ecological changes

2. Freshwater Management: Create freshwater stores upstream to regulate dry season inundation

3. Habitat Protection: Better protection of non-affected mangroves

4. Restoration Activities: Implement restoration where feasible

For Management Improvement

1. Transboundary Cooperation: Increase coordination with Bangladesh Sundarbans World Heritage site, including frequent meetings between management authorities

2. Monitoring Enhancement: Improve monitoring of populations, including aquatic animals

3. Resilience Research: Conduct research into biodiversity and ecosystem resilience facing current and future threats

4. External Threat Management: Greater focus on preserving values from threats outside the site

5. Funding Increase: Address inadequate funding and capacity to tackle wider threats

For Value Preservation

1. Ecosystem-level Assessments: Conduct comprehensive assessments of threat impacts to fully determine resilience of site values

2. Sustainable Management Action: Increase adequate and sustainable management action as number and intensity of threats likely to increase