Boris Weitzmann
Marine biologist and coordinator
of marine activities at Alive Foundation
It is the only known population on the Catalan coast of this threatened species.
Divers from the Alive Foundation together with researcher Dr. Enric Ballesteros from the CSIC located, in July 2021, what is so far the only population of Sargassum trichocarpum in Catalonia .
Sargassum is a highly endangered species, an indicator of good environmental quality, as it is very sensitive to human impacts. The only known population in Catalonia is found in Cala Montgó, within the protected marine area of the Montgrí, Medes Islands and Baix Ter Natural Park, at a depth of 20 meters and attached to a rock in the middle of a fine sandy bottom. When seen under the sea, it is observed that its gas-filled vesicles (aerocysts) give it buoyancy, so that the cauloid (the “trunk” of the algae) is perfectly perpendicular to the bottom. In this way, the entire algae can better receive light to carry out photosynthesis.
In order to check the health status of the population and assess the actions to be taken to ensure its conservation, this April we were accompanied by two members of the CSIC, doctors Simone Mariani and Francesco Martini, specialists in vulnerable and endangered algae species on the Mediterranean coast.
We also verified the presence of another endangered species present in Cala Montgó. It is Cystoseira foeniculacea , an epilithic species that can live both at very shallow depths and at some depth. Both species are protected by different national and international laws and agreements.
As a result of the survey, it has been verified that the sargassum population is in a very good state of conservation.
