Who will mourn the Sundarbans?

The 7.7 million inhabitants of the largest mangrove forest in the world face a bleak future as coastal erosion and high tides consume their islands.

The Sundarbans, the world’s largest contiguous mangrove region, has its own unique physiographical, ecological, economical, and sociocultural individuality. It is home to nearly eight million people. | Photo Credit: Shailendra Yashwant

The “beautiful jungle” that straddles India and Bangladesh to form the world’s largest mangrove forest known as Sundarbans is facing a coastal erosion emergency that threatens the survival of its 7.7 million inhabitants, 2.7 million in Bangladesh and five million in India. And climate change is only hastening the inevitable.

The Sundarbans is known for its exceptional diversity of flora, which includes 528 species of vascular plants, and is recognised as a Ramsar and World Heritage Site. | Photo Credit: Shailendra Yashwant

“Bonbibi [the guardian spirit] will protect us from the tigers and crocodiles, but who will protect us from cyclones and the rising sea?” asks Debabrata Babu, a 58-year-old resident of Gosaba Island in the Sundarbans of West Bengal. Babu has survived six cyclones, four of his houses were gobbled up by the rising sea, and the land that remains is highly saline and uncultivable.

The embankments are frequently breached, and when they break, they are difficult to repair until after the waters recede. As a result, the residents are often marooned, cut off from essential infrastructure. | Photo Credit: Shailendra Yashwant

Since 1783, when Tilman Henckell, the magistrate of Jessore (now in Bangladesh), ordered the clearing of the Sundarban forests for timber, the early migrants and settlers here have had to face the ravages of cyclones, shifting rivers, high tides, floods, erosion, and the ever-looming threat of attack by the Bengal tiger.

“Some families continue to live in vulnerable locations due to high land prices and a lack of job opportunities elsewhere,” says Debabrata Basu. | Photo Credit: Shailendra Yashwant

Climate change has exacerbated all the natural phenomena to the extent that in the Sundarbans life is increasingly under threat. A 2009 study estimated the costs of the environmental damage and health issues at Rs.1,290 crore annually¹ ($250 million). In fact, in the last two decades, more climate refugees have fled here than from any other ecosystem in the region. An estimated 62 per cent of the workforce has lost their original livelihoods, and 1.5 million people have been forced to move.

In the world’s largest mangrove forest, tigers and snakes may pose the most immediate danger. But it’s the inevitability of a changing climate that threatens the very state of the Sundarbans and its inhabitants, both human and wildlife. The Sundarbans bear little responsibility for global emissions but are forced to suffer the consequences. | Photo Credit: Shailendra Yashwant

The name Sundarban, which means beautiful jungle in Bengali, perhaps comes from the Sundari trees (Heritiera fomes) that once thrived in this UNESCO World Heritage Site, but are now listed as endangered by the International Union for Conservation of Nature. Mangroves act as vital “carbon sinks”,² efficiently removing CO₂ through natural carbon capture. One study³ estimates that the Sundarbans have soaked up 45 million tonnes of carbon dioxide.

Tourist boats in the Sunderbans. The growing tourism business benefits the local economy, but at the cost of damage to the Sundarbans due to habitat destruction and unplanned development for hotel construction, pollution by garbage disposal, poor sanitation, and noise caused by mechanized boats. | Photo Credit: Shailendra Yashwant

Through centuries, tides have formed the Sundarbans; the islands vanish and reappear in a natural rhythm. But over the last couple of decades, the variations have become more extreme, and the pace of erosion outpaces the global average.⁴ The Sundarbans, which extends over an area of 10,000 square kilometres, is slowly shrinking⁵ and has lost “almost 16 sq km of vegetation per year since 1991” because of human encroachment and climate change.

Satellite imagery shows that the sea level has risen in the Sundarbans by an average of 3 cm a year over the past 20 years. Also, a reduction in sediment flow has resulted in loss of land mass. Some of the islands will disappear completely within the next 50–100 years at the current rate. | Photo Credit: Shailendra Yashwant

As the sea level rises and the tides swell, houses are raised high above the ground and embankments are strengthened every year. But the breaches continue unabated, as cyclone after cyclone batters the region. Four cyclones in the last five years—Fani (2019), Bulbul (2019), Amphan (2020), and Yash (2021)—have destroyed embankments even as they were being repaired.

An estimated 1.5 million people will have to be permanently relocated because the rise in sea level will make it impossible for them to live there or earn a living. | Photo Credit: Shailendra Yashwant

“The challenge for the government is not only to save lives but ensure livelihoods and preserve this ecosystem,” Javed Ahmed Khan, West Bengal’s Minister in-charge of Disaster Management and Civil Defence, told this writer when he visited the region in March this year.

Although the Sundarbans are a crucial natural blockade against natural disasters and enriched with biodiversity, there is a deterioration in the health of mangrove forests due to increased salinity, temperature rise and rainfall reduction. The coverage of mangrove forests between 1975 and 2020 found that mangrove forests have been decreasing in density by an estimated annual rate of 1.3 per cent. | Photo Credit: Shailendra Yashwant

The State government is now looking for climate finance to repair and restore the loss and damage. There are plans to commission a comprehensive audit of embankments to find the best-suited methods to strengthen them against the onslaught of the sea.

Shailendra Yashwant is an independent environmental writer and photographer. He is Senior Adviser, Communications and Advocacy, at Climate Action Network South Asia based in India.

Endnotes

1. https://openknowledge.worldbank.org/entities/publication/fefa942e-d4b2-5712-8476-437175a5d55a
2. https://unece.org/forests/carbon-sinks-and-sequestration
3. https://link.springer.com/article/10.1007/s11769-019-1042-2
4. https://www.saconenvis.nic.in/publication/Sea%20Level%20and%20associated%20changes%20in%20the%20Sundarbans.pdf
5. https://earth.org/the-worlds-largest-mangrove-forest-is-shrinking/