It has a Latin name,
rugulopteryx okamurae
, but this invasive algae which takes its ease in the harbor of Marseille, from the creeks to the Côte Bleue, does indeed come from Japan.
Very brown, stringy and disturbing the water, it undoubtedly appeared in the Mediterranean via embryos of oysters or sea urchins imported from the land of the rising sun.
Since June, numerous collection operations on the coast have been organized.
To "respond to legitimate concerns", the algae, which produces hydrogen sulphide by decomposing, was analyzed by marine firefighters who concluded that it was "harmless" for humans.
The town hall also seized the laboratories of the University of Aix-Marseille to understand the reasons for its rapid reproduction, which can endanger biodiversity.
"We are all concerned"
"We can count on laboratories and qualified researchers who are working to better understand this alga", hopes Aurélie Biancarelli-Lopes, assistant in charge of research. "To act on its proliferation, it is first of all necessary to better understand this species, to study its evolution, and to assess its impact on the local flora and fauna".
Faced with this invasion, the city of Marseille has just requested the help of the Metropolis to increase collections on the beaches. "The scale of the phenomenon goes beyond the borders of our territory", explains Christine Juste, deputy in charge of the environment. “If the city of Marseille is already mobilizing strongly, all communities must work together to give themselves the means to act in the face of this proliferation. When our marine biodiversity is threatened, we are all concerned. "