New WWF study highlights urgent need to protect Mediterranean Seagrass meadows from anchoring damage

Rome 6 June 2025 -  Just launched, WWF Mediterranean's report has revealed the scale of damage being inflicted on the Mediterranean’s seagrass meadows by vessel anchoring, with over 50,000 hectares of Posidonia oceanica—a key seagrass species—potentially affected in 2024 alone. This is the equivalent of an annual economic loss in terms of ecosystem services of over 4 billion euros per year¹.

The report, Safeguarding Mediterranean Seagrass Meadows from Anchoring Damage, draws on advanced Automatic Identification System (AIS) data to map anchoring pressures on seagrass across the region and is launched on 8 June, on World Oceans Day. The study identifies anchoring as one of the most critical and preventable threats to Posidonia oceanica, a slow-growing, endemic species vital for biodiversity, shoreline protection, and climate regulation. Posidonia meadows support fisheries, sequester vast amounts of carbon, comparable to the emissions of 430 million cars annually, and shield coastlines from erosion. Yet, up to 34% of these meadows have been lost in the last 50 years.

The WWF report finds that over 179,000 vessels may have anchored on seagrass in 2024, 45% of them larger than 24 meters. Large vessels are responsible for nearly 60% of total impacted areas, with hotspot regions including Italy, Spain, Türkiye, Greece, and France. In some zones, up to 50% of meadows have been potentially affected by unregulated anchoring. Conversely, areas with strict anchoring regulations, such as the south of France, show significantly lower impact rates.

“Anchor damage is slow to heal, with scars taking even more than 100 years to recover. Protection and improved management represent the most effective ways to safeguard these critically important ecosystems” explains Mauro Randone, Manager of the Ecosystems Programme at WWF Mediterranean.

The report's key recommendations include:

The report concludes with a strong call to action: Preserving and restoring seagrass meadows isn’t just an ecological mission, it’s a strategic necessity for our future. Governments must act now to ban harmful anchoring practices and promote sustainable marine use.
 

1 €86,000 per hectare/year is the value of the ecosystem services provided by Posidonia oceanica according to a recent decision by a French Court.