Nature at Work: Understanding Posidonia on Our Beach

Dear Guests,

We would like to inform you that the leaves that are found on our beach are from the Posidonia Oceanica plant. Posidonia oceanica is not an alga, it is in fact a marine plant (phanerogam).

It is a species of sea-grass that is endemic to the Mediterranean Sea. This marine plant forms large underwater meadows that are considered to be of high importance to the environmental conservation of the region. They occupy an area about 3% of the basin (corresponding to a surface area of about 38,000 km2). Its role is incredibly important for the local ecosystems since many other species find their nutrients and housing in Posidonia meadows.

The Posidonia only grows in clean unpolluted water and is considered by scientists an infallible testimony to a healthy marine environment. The sea grass is called the lung of the Mediterranean as it absorbs up to 16 litres of carbon dioxide per square metre/day. We are lucky here in the Greek islands to have a large existence of this important plant. Let's hope it will remain so, for a very long time.

The plant is already considered a threatened species requiring protection in order to preserve biodiversity. Thus, Posidonia is declared protected species by the European Community as a member of the "habitats" of E.U.

Balls of fibrous material from the foliage of the plant, known as egagropili, are washed up to the beach. As they dissolve they become significant part of the nutritional chain for the marine species. Thus, these uprooted leaves are protected from the Hellenic Ministry of Environment, Physical Planning & Public Works, as well. Their collection and removal from the beach with technical means is not allowed.