Ostreopsis Ovata

Ostreopsis ovata are microscopic algae that thrive in warm, still, shallow waters on rocky coastlines.

What is Ostreposis ovata?

A recent proliferation that scientists attribute in part to climate change currently going on.

Originating in tropical areas, they are believed to have reached temperate regions of the planet partly due to climate change, which made the Mediterranean suitable to their development. The microalgae were first observed in France in 1972, and are now regularly found in the summertime along the Mediterranean coastlines of France, Italy and Spain.

Why should we be concerned about Ostreopsis Ovata?

When conditions are favourable to their development, Ostreopsis ovata proliferate and release a toxin that can harm marine biodiversity and coastal users. Ostreopsis ovata can therefore infect swimmers, watersports enthusiasts and all other users of the sea and coast.

Surfrider's involvment

Study, understand, inform and mobilise for a bette coastal water quality.

Make that invasive algae a new fight

When they multiply, Ostreopsis ovata have the potential to cause serious environment and health issues. This is why Surfrider Foundation Europe decided to include these microalgae in its Mediterranean water quality monitoring network in 2010. 

The organisation hopes to study and understand how the microalgae found their way to the Mediterranean coastline, thus expanding knowledge and information on the topic. Every summer, Surfrider Europe sets up an environmental watch and a water sampling campaign in water activity areas in the French regions of PACA, Occitania and Corsica. 

This mission also aims to educate the general public and bring together various players to help tackle this problem. Several resources on Ostreopsis ovata have been created, including a leaflet and a poster which were handed out to water activity enthusiasts in the summer of 2018. 

If you develop flu-like symptoms after having spent time in the water,


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