Oil spill: Sunderbans face a new threat; Bangladesh still grappling with the disaster

"The short term effect of oil spill will be the immediate degradation of the sensitive biodiversity," said 46-year-old Anurag Danda, head of the Climate Adaptation Programme and Sundarbans Landscape department of WWF, India. Ecologists and environmentalists are a worried lot over the December 9 oil spill in the Sunderbans delta, in Bangladesh.

Hindered by dense fog in the wee hours, a cargo vessel rammed into the tanker Southern Star 7, carrying some 92,000 gallons of bunker oil, in the Sela river, at the entrance to the Bangladesh Sundarbans, southeast of the river port of Mongla. The collision occurred inside the Chandpai dolphin sanctuary, spilling of more than 3,50,000 litres of furnace oil into the waters.

Seven crew members jumped ship and swam to the shore but it took almost five days to fish out the body of Captain Mokhlesur Rahman.

"Although the Indian part of the delta will not be affected, we have received information that the oil spill has already spread across 150 sqkms," Anurag said, adding that there are several reasons for it. Since it is an estuary, there is constant water movement in the form of tides, whereas that is not so in open marine regions which can be more effectively contained. Moreover, there is a lack of expertise in dealing with oil spills in delta rivers, with technology being available mostly for open marines. Care has to be taken so that chemicals which are normally used for such a clean-up does not affect the marine life.

The immediate effects can be disastrous, with oil cover on the banks spelling a death sentence for burrowing creatures like crabs. The oil on the water will cut off oxygen, thereby affecting the fish population. "However, it is hoped that the dolphins, which are a very intelligent mammals, will keep away from the affected regions," said Anurag. As recently as in 2011, New York-based Wildlife Conservation Society had discovered a population of 6,000 Irrawaddy dolphins in the Bangladesh Sundarbans.

"An oil spill doesn't limit its ill-effects to marine life. In a chain reaction, it can also harm birds that feed on fishes, as well as flora and fauna surrounding the water," said Dr Anita Mukherjee, professor of botany with the Calcutta University. "The components of oil by themselves is harmful for life, and can take years to counter their ill-effects," she added.

Sunderbans spread
The world's largest delta of Sundarbans is spread across India and Bangladesh, it has been formed by three rivers -- Ganga, Brahmaputra and Meghna. Declared as a UNESCO World Heritage site, it is an archipelago of more than a hundred islands. It is famous for its mangrove forests and home to several endangered species like the Royal Bengal Tiger, Ganges and Irawadi dolphins. The Sundarbans covers approximately 10,000 square kilometres of which 60 percent is in Bangladesh with the remainder in India.