Namita and her mother Sabita in the tiny Lohachara island of the Sunderbans saw the shore pushing in closer almost everyday, but had no idea about the devouring power of the sea. One night, the tide almost touched their hut, forcing the panic-stricken family to pack their belongings and leave next morning for Sagar, the largest island in the Sunderbans.

It was time for rejoicing for the family, as they met nearly 700 of their former island mates over there who shifted much earlier for the same reasons.

It was in the late 1999 that Sabita moved to Sagar; Suparibhanga, another island in the vicinity which is also known as Bedford, met the fate of Lohachara in less than a year. Suparibhanga has no official record of human habitation though.

The seas have been rising across the Sunderbans, the 100-island conglomerate in the Gangetic estuarine delta in the Bay of Bengal. The 26 December 2005 tsunami wreaked havoc in the Andamans & Nicobar archipelago, with many islands going under the sea while some had been partially submerged. But the tale of vanishing islands has largely been ignored.

Glaring climate changes in this fragile estuarine ecosystem, home to the famous Royal Bengal Tiger and innumerable species of flora and fauna, poses a grave threat as the rising sea levels threaten to wash out almost 15 per cent of the existing 9,000-plus sq.km area of the islands, says Dr Sugata Hazra, an eminent environmentalist and director of the School of Oceanographic Studies, Jadavpur University.

The latest United Nation's report on climate change released on Friday by the International Panel on Climate Changes (IPCC) describes an accelerating transition to a warmer world – an increase of 3°C is expected this century – marked by more extreme temperatures including heat waves, new wind patterns, worsening drought in some regions, melting glaciers and Arctic ice, and rising global average sea levels.

The vanishing islands in the Sunderbans over the last decade only reconfirms this. The IPCC report quoting its chief Dr R K Pachauri mentions that the impact “will be more visible in the Sunderbans in the coming years and in the glaciers. Climate change is impacting everyone, but will effect the poor population more."

Sagar island where lakh of people congregate on the Makarsankranti day for a holy dip, faces the worst threat. Mujibullah, 37, who hails from the island and sustains his family on seasonal catch of Hilsa, is worried as it is clear to him that the west end of the island -- Boatkhali and Laudhas - is fast getting eroded. Close by is Ghoramara which is also found to be sinking.

Two missing
Researchers led by Dr Hazra who undertook a physical mapping of each of the islands last year, found 100 islands instead of 102 mentioned in the official record. There has been no trace of other two. "The satellite images have revealed the absence of two islands. The find has spurred us into further investigation, confirming our worst apprehension. We have noticed that rainfall has shifted to the post-monsoon period, firmly indicating a climate change. Two more islands in the south are also being submerged, affecting the tiger habitation," points out Dr Hazra.

According to a rough estimate, at least one lakh people will have to be evacuated from the 12 threatened inner estuary islands of the Sunderbans in the next ten years if the present rate of submergence persists. And Dr Hazra believes it will.

His contention has been supported by the fact that Trinket island in the Andaman & Nicobar archipelago which had been submerged and bifurcated following raging waves of Tsunami, has not re-surfaced so far.
India's natural disaster management programme revolves around instant calamities like earthquake, flash flood, drought and more recently tsunami. "What about the slow onset of disasters like vanishing islands displacing hundreds of habitats?" asks Dr Hazra.

Will the government sit up and take notice before hungry sea swallows the Sunderbans?

Vanishing species
Is the phenomenon posing a threat to the famous animal life in the Sunderbans, the likes of  Royal Bengal Tiger, one horned Rhino, Cheetal deer and Water Buffalo ? "Yes, it is, given the existing trend," feels the expert and other scientists.

In fact, the researchers have found that climate change has already taken a heavy toll in the animal life. The water buffalo, Javan Rhino and Swamp deer have all become extinct in the Sunderbans in the last century. The Barking deer has  vanished from all islands except Halliday where some dozens are still left.

Even as indications confirm that tigers have finally adapted themselves to drinking salt water, they prefer brackish water conditions (mix of river and sea waters) which is presently available only in the northern tip of the Sunderbans and the tigers are gradually shifting base there, says Pranabesh Sanyal, a well-known tiger expert and former director of the Sunderban Development Board.

"With Bhangaduani island (having the highest concentration of tigers) facing the intense heat of erosion, the tiger habitat itself is fast shrinking which explains frequent incursions by the animal into the human living zone," he explains.

Next, in the line of fire are some rare and exotic plant species, particularly the mangroves. The Sunderbans are home to the largest mangrove biodiversity in the entire world. With vanishing islands, they too would obviously suffer an identical fate.



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