Batteries, nets and ropes that have been left in the ocean from fishing are lethal for decades to the sea life around them.
More than 150,000 seals, whales, dolphins and porpoises are estimated to be killed annually by lost fishing equipment, along with thousands of seabirds, turtles and sharks.
But now divers in Thailand are trying to turn the problem of these so called ghost-nets into a solution, as our South East Asia correspondent Siobhan Robbins reports.
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