Illegal anchoring over protected Posidonia seagrass meadows has more than doubled in Ibiza in just one year, according to new figures from the 2026 Mar Balear Report, raising fresh concerns about the pressure being placed on the island's marine environment.

The number of inadequate anchoring incidents detected in Ibiza increased from 1,719 in 2024 to 3,468 in 2025, representing a 101.7% increase. The proportion of inadequate anchorings also rose sharply, from 10.3% to 21.3%.

The increase is particularly striking because Ibiza is moving in the opposite direction to most of the Balearic Islands.

Ibiza Stands Out From the Rest of the Balearics

Across the Balearic Islands, the overall proportion of inadequate anchorings fell to 6.4% in 2025, one of the lowest levels recorded since the monitoring service began.

Mallorca improved from 6.8% in 2024 to 6.4% in 2025, while Menorca saw a more significant reduction from 8.7% to 5.3%.

Formentera was an exception alongside Ibiza, although its increase was considerably smaller, rising from 1% to 2.2%.

Ibiza, however, recorded by far the sharpest deterioration, reaching 21.3%. That means the island's detected rate was more than three times the Balearic average in 2025.

Why Posidonia Matters

The concern goes beyond individual boats dropping anchors in the wrong location.

Posidonia oceanica is a protected Mediterranean seagrass that forms extensive underwater meadows around the Balearic Islands. These ecosystems provide habitat and nursery areas for marine species, contribute to water quality and help protect the coastline.

Anchors and their chains can physically damage the seabed and uproot the slow-growing seagrass. Repeated anchoring in the same areas can therefore cause long-term degradation of these important underwater habitats.

The species and the habitat it creates are protected under European, Spanish and Balearic environmental legislation.

Recreational Boating Continues to Increase

The Mar Balear Report highlights the growing presence of recreational boats along the Balearic coastline, particularly during the summer months.

However, the report also notes that authorities still do not have precise figures for the total number of vessels navigating and anchoring around the islands.

The combination of increasing recreational boating and intense summer pressure creates an ongoing challenge for the protection of marine habitats such as Posidonia.

Authorities Are Increasing Surveillance

The Balearic Government operates the Posidonia Surveillance Service through the Institut Balear de la Natura (IBANAT), particularly during the months when pressure on the coastline is highest.

In 2025, the service operated with 19 vessels and carried out almost 181,500 information and surveillance actions across the islands. Despite Ibiza's deterioration, these efforts have contributed to a significant reduction in the overall rate of inadequate anchoring across the Balearics.

The contrast between Ibiza and the rest of the archipelago is therefore one of the key findings of the latest figures.

Eco-Friendly Mooring Fields Offer an Alternative

One of the measures being used to reduce damage to Posidonia is the installation of low-impact ecological mooring fields, particularly in areas classified as Sites of Community Importance.

These systems provide designated places for boats to moor without dropping traditional anchors directly onto sensitive seabeds.

In 2025, Ports IB managed eight low-impact ecological mooring fields across the Balearics.

Mallorca had three fields with 115 moorings. Menorca had two fields and 94 moorings, Cabrera had two with 90, and Formentera had two with 88.

Ibiza had one field with 39 moorings. Despite having fewer moorings overall, Ibiza allocates a relatively high proportion of its spaces to larger vessels, with 21% intended for boats measuring more than 15 and 20 metres in length.

Marine Waste Is Another Growing Concern

The same Mar Balear update also highlights challenges surrounding marine litter.

The number of vessels involved in floating-waste collection has fallen significantly over the past decade. The cleanup fleet has declined from around 40 vessels in 2010 to approximately 22 or 23 vessels since 2021.

That reduction has coincided with a major decline in the amount of waste collected, from more than 200 tonnes per year on average between 2004 and 2010 to just 28 tonnes in 2024.

Plastic continues to represent a significant proportion of marine waste, creating additional risks for marine life and coastal ecosystems.

A Growing Challenge for Ibiza

The latest figures present a complicated picture.

Across most of the Balearic Islands, efforts to reduce inappropriate anchoring appear to be producing results. Yet Ibiza has experienced a dramatic reversal, with detections more than doubling in a single year.

For an island whose identity and tourism economy are closely connected to the Mediterranean, protecting its underwater environment is increasingly important.

Posidonia meadows are largely hidden beneath the surface, but their importance to Ibiza's marine ecosystem is enormous. The latest figures show that managing the growing pressure from recreational boating remains one of the island's most urgent environmental challenges.