Kelp, a Forest Under the Sea

Director: Félix Urvois and Matthieu Le Mau

Producer: Nathaneal Friloux

Country: France


At the foot of the Breton coast stretches a fascinating and secret underwater world. Kelps, brown algae that can reach several meters, form one of the largest submerged forests in Europe. This ecosystem, which is found in most of the world's temperate waters, is home to a very rich biodiversity, influences the climate and allows an entire maritime economy to exist. Like the largest primary forests, the kelps form an essential living heritage that defines the identity of coastal territories.

But the functioning of these environments remains surprisingly unknown. Yet there is urgency, with global warming a large part of the French underwater forests could have disappeared within 30 years. Thanks to a historic collaboration between Breton and Chilean scientists, solutions are fortunately beginning to emerge. Algae cultivation provides promising answers, but the challenge remains daunting. It is a question of not repeating at sea the mistakes made in the past on our agricultural lands. Can we imagine tomorrow an aquaculture serving the coastal economy and the environment?


Kelp is a type of seaweed that grows in deep sea forests. These algae play as important a role as trees in capturing carbon dioxide and, icing on the cake, they are also a source of food. From France to Chile, this film explores the history, economic and scientific potential of kelp to build a new type of sustainable agriculture, maintain biodiversity or fight against global warming.