"It's a farce that's been going on for too long": the algae industry between ambitions and illusions

Article reserved for subscribers

The government launched work in early 2025 aimed at developing an algae sector based on cultivation rather than fishing. But the societal and environmental issues are likely to be delicate.

"The market is evolving. No seaweed farmer will launch on a large scale if they are not certain that a manufacturer will buy their production." (Tristan Vergnault/Libération)

Ten o'clock in the morning, low tide in one hour and nine minutes. More egrets than clouds in the sky of the Île de Ré on this Tuesday in June. Louis Chatin parks the truck at the water's edge. He stays in his shorts and sneakers, while seasonal workers Hikaru and Maëlys put on waterproof pants to wade out to this tiny, bright green islet: a colony of mussels covered in ulva lactuca . The sea lettuce will end up as tartare on a piece of bread, as dehydrated twigs in the middle of a salad, but you still have to work hard to harvest it, using your back and a knife. There's work to be done: 50 centimeters of tide later, at the appointed time, the water has receded, and seaweed has sprung up everywhere.

Lettuce grows alongside wakame, kombu, ogonori… Louis Chatin hopes to harvest 15 tonnes of it