The increasing global temperature may spell doom for the Sunderban tigers as a WWF study has cautioned that rise of 28 centimetre in sea levels will engulf 96 per cent of their habitat.

The findings, though specific for Bangladesh, may be a cause of concern for India as well because the Sunderbans are spread across India and Bangladesh having same ecosystem and tiger population.

The increase of 28 cms from the sea levels of the year 2000 will cause 96 per cent decline in tiger habitat of Sunderbans in Bangladesh while the number of breeding tigers would be reduced to less than 20, Colby Loucks of WWF-United States said in a paper. "We find that the Sunderbans, and its biodiversity, may be vulnerable to much lower increases in sea level than previously thought," he said.

The researcher say the situation may come in about next 50-90 years if Intergovernmental Panel on Climate Change (IPCC) estimation of sea level rise is taken into consideration.

"The Sunderbans are spread across India and Bangladesh with about 5,000 sq kms in Bangladesh and 4,000 sq kms in India. Although the political boundaries define the region, the entire area has similar ecosystem. Any environmental change taking place will have effect on both sides," Joint Director Sunderbans Biosphere Reserve Raju Das told reporters.

However, some leading tiger experts are not convinced by the study as tides in the area drown considerable part of the reserve in both sides on regular basis. There are estimated 350 Royal Bengal Tigers in the Bangladesh Sunderbans, according to UNESCO. As per estimates of Project Tiger in India, there were 245 striped cats in 2001 census on its Indian side.

On the Indian side, the situation may not be as bad as in Bangladesh as mangrove covers are still safe on Indian coastline in comparison to the other side, experts say. "They (Bangladesh) have larger coastline besides they have lost a major chunk of mangrove cover which acts as wall against inundation of salty sea water," Former Director of Project Tiger and leading tiger expert P K Sen said.

He agreed that because of common eco-system, the impact may cascade on Indian side as well but added that islands in the reserve keep changing as new ones come and older get drowned in the delta but it does not have much impact on the tiger population.

When asked about the findings of the WWF study group, he refused to comment on the authenticity of its findings. "While tigers are a highly adaptable species... the Sunderbans ecosystem has become an isolated refuge, boxed in by humans and the sea. Although there is considerable uncertainty regarding the degree of future habitat loss due to sea level rise, it is still imperative to act now to mitigate the potential habitat loss," the researchers say.