Sundarbans National Park

Five Milestones

• 1973: the area is declared the core of Sundarban Tiger Reserve, under Project Tiger.
• 1977: the area is declared a wildlife sanctuary.
• 4 May 1984: the core 1,330.10 sq km is declared Sundarbans National Park.
• 1987: UNESCO inscribes Sundarbans National Park as a World Heritage Site.
• 30 January 2019: the Sundarban Wetland is designated a Ramsar Site.

The World’s Largest Mangrove Forest

Sundarbans National Park sits in South 24 Parganas district, West Bengal, in the Ganges-Brahmaputra delta. It’s the world’s largest mangrove forest, shared between India and Bangladesh. It became the core area of Sundarban Tiger Reserve in 1973, under Project Tiger. Then a wildlife sanctuary in 1977. Then a National Park on 4 May 1984.

• Two different sizes: the core National Park area covers 1,330.10 sq km. The wider Sundarban Tiger Reserve covers 4,200 sq km.
• A shifting delta: sediment carried by the Ganges and Brahmaputra keeps reshaping the delta’s islands and channels, even today.
• A recurring tension: South 24 Parganas is one of India’s most densely populated districts. That adds pressure at the reserve’s edges. Balancing local livelihoods against strict wildlife protection remains a genuinely difficult challenge.

A Growing Tiger Count

UNESCO declared it a World Heritage Site in 1987, under Criteria (ix) and (x). It became a Ramsar Wetland, named “Sundarban Wetland,” on 30 January 2019. The Indian Sundarbans held 101 Royal Bengal tigers, per the 2022 tiger census. That’s up from 88 in 2018. These tigers form a genetically distinct population, adapted specifically to the mangrove-swamp environment. They also tend to be smaller than tigers elsewhere in India.

• Their prey: chital and wild boar make up much of the tigers’ natural prey base within the mangrove forest.
• A shared faith: Bonbibi worship crosses religious lines, followed by both Hindu and Muslim communities living around the Sundarbans.

Early Protection and a Biosphere Reserve

The first forest management division over the Sundarbans was set up in 1869. British colonial administrators were mainly interested in timber extraction. In 1875, a large portion of the mangroves was declared reserved forest, under the Forest Act, 1865. The Government of India declared Sundarban Biosphere Reserve in 1989. UNESCO added it to its World Network of Biosphere Reserves on 10 November 2001. This biosphere reserve covers a much larger area than the national park core. It includes inhabited islands, where fishing, honey collection, and small-scale farming remain the main livelihoods.

A Web of Channels, and a Cyclone Shield

The Sundarbans’ mangrove islands are crossed everywhere by tidal river channels and creeks. Besides tigers, the forest hosts saltwater crocodiles, Gangetic dolphins, and diverse bird and invertebrate species. It also acts as a natural buffer against cyclones, for the densely populated coast behind it. Major cyclones striking the Bay of Bengal have repeatedly weakened after passing through this mangrove belt.

• A shared heritage: Bangladesh’s own Sundarbans forest was separately declared a UNESCO World Heritage Site in 1997.
• Its namesake tree: the Sundari tree, which gives the Sundarbans its name, is one of the region’s most common mangrove species.
• Breathing roots: mangroves here have adapted special root systems, called pneumatophores, that rise above the mud to breathe in oxygen-poor, saline soil.

Swimming Tigers and a Five-Fold Shield

Sundarbans tigers are unusually strong swimmers. They move between mangrove islands through tidal creeks, an adaptation rare among big cats. The Sundarbans connects to India’s wider tiger-conservation network, alongside Kaziranga, Gir, and Corbett. But its brackish mangrove-swamp habitat is unlike any of the other three. Rising sea levels and stronger cyclones are expected to reshape the Sundarbans over coming decades. That adds real urgency to its ongoing conservation.

Mangrove Restoration, and a Decade of Growth

On 29 July 2026, West Bengal’s forest department began restoring 1,600 hectares of illegally encroached Sundarbans mangrove forest. The department demolished unauthorised fisheries built during the previous state government. It is investigating a nexus with local politicians and officials. Separately, on 11 August 2025, the Union government told Parliament that West Bengal’s mangrove cover grew by 22.16 sq km over the last decade. It rose from 2,097 sq km in 2013 to 2,119.16 sq km in 2023. The government credited the MISHTI programme and CAMPA-MGNREGS convergence, alongside anti-poaching and satellite-telemetry monitoring under Project Tiger.