It is sometimes mistaken for a seaweed: posidonia (Posidonia oceanica) is in fact a marine flowering plant, endemic to the Mediterranean. Its vast meadows are often described as one of the most precious ecosystems along our coasts, and they are very much present in the Cerbère-Banyuls reserve.
Why the meadow is essential
- It shelters a wealth of biodiversity: a nursery and refuge for many species.
- It produces oxygen and stores carbon.
- It protects the coastline by softening the energy of the waves and holding back sediment.
A fragile ecosystem
The posidonia meadow is sensitive to anchoring, coastal development and any decline in water quality. Its growth is very slow: a few centimetres a year at most, which means a damaged meadow takes a very long time to recover. On the Côte Vermeille, these underwater prairies are home in particular to the fan mussel, a large shellfish now endangered. Preserving the meadow therefore also means preserving those who live in it.
The diver’s part to play
Mastering your buoyancy, never anchoring in the meadow, taking nothing away: these are all simple habits that help preserve the ‘green gold’ of the Mediterranean.
To find out more, the scientific teams at the Banyuls Oceanological Observatory study these habitats: a subject at the heart of the festival’s Protect strand.