The river routes through the Sundarbans must be closed permanently to avert further accidents that might threaten the biodiversity and ecosystem of the world's largest mangrove forest, a number of experts have said.

They noted that the authorities failed to tackle the recent disaster in the Sundarbans after a tanker sank in the Shela river on December 9 and spilled thousands of litres of oil into rivers and canals of the forest.

The experts were speaking at a roundtable -- Sundarbans in great danger: the measures need to be taken immediately -- organised by Bangla Daily Prothom Alo at its office in the capital's Karwan Bazar yesterday.

The speakers urged the government to take both short and long-term preparations to stop recurrence of such incidents.

Criticising Shipping Minister Shajahan Khan for his remark that the forest wouldn't be affected by the spilled oil, they said there were reports of deaths of animals in the forest.

The oil spill would have adverse effects on the biodiversity of the forest in the long run, said the experts.

Eminent environmentalist Prof Ainun Nishat said the spilled oil could have been easily collected from the rivers and canals, using “booms”, made of plastic pipes and nets, with the help of local fishermen.

But that didn't happen due to ignorance of the government organisations concerned, and oil spread over a vast area increasing the damage to the forest.

The government should have engaged members of the army and the navy to deal with the situation, he said.

Dr Atiq Rahman, executive director of Bangladesh Centre for Advanced Studies, said the authorities could have contained the oil spill to a certain area, and then remove the oil from water. 

Prof Abul Bashar of Dhaka University said the oil spill has harmed the forest's genetic resources that are unique in the world.