If you think fishing nets are made of natural rope, think again — they're made of plastic. Every year, some 80,000 km² of nets are lost and abandoned at sea. As they drift aimlessly, these so-called "ghost nets" litter the ocean floor and trap nearly everything in their path. We take a closer look in this Edition of Down to Earth.

Robot to the rescue

The problem of "ghost nets" is widespread in the south of France, where scientists and divers often come to the rescue in order to remove fishing gear that's been abandoned. French association 'Les Ressources Sous-marines' is one of them. The small company has built a robot that can scour the sea floor in search of nets and retrieve them.

The team receives a call warning them of a possible sighting off the island of Porquerolles. The robot is equipped with a camera and can reach a depth of 300 metres.

Once the net has been found, the rover will collect it and bring it to the surface. Divers can also be deployed to assist in the process.

"As people who love the sea, we're obviously not big fans of ghost nets. We'd love to get rid of them," says Olivier Trubert, the association's vice president.

"It breaks our hearts but it's also heartbreaking for fishermen who lose their nets and their livelihoods."

The vicious cycle of abandoned gear

The scientific community takes the danger posed by ghost nets very seriously. Sandrine Ruitton from the Mediterranean Institute of Oceanography explains how fishing nets wreak havoc underwater.

"Fishing nets lost at sea cannot be recycled," says Meunet. "We can’t transform them."

Read more on FRANCE 24 English

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