Tracking Bottom Fishing in EU Waters

[January 15, 2025] — In 2016, the European Union adopted the Deep-sea Access Regulation, banning all bottom trawling below 800 meters in the Northeast Atlantic upon its 2017 entry into force. This landmark regulation aimed to safeguard some of the ocean’s most biodiverse and fragile habitats, including seamounts teeming with cold-water corals and sponges, known as Vulnerable Marine Ecosystems (VMEs).

In November 2022, the European Commission implemented a key provision of this regulation by closing 87 areas (between 400–800 meters depth) of European waters to bottom contact fishing. While these protections have significantly reduced fishing activity, a new open-access study published in Science Advances reveals that bottom contact fishing activities persist in these protected areas.

By analyzing fishing activity data from Global Fishing Watch, the study compared pre-closure (November 2021–October 2022) with post-closure data (November 2022–October 2023). Researchers from Marine Conservation Institute, the Deep Sea Conservation Coalition and BLOOM Association found an 81% reduction in bottom contact fishing activity, with fishing hours dropping from 19,000 to 3,500 following the closures.

Progress and Gaps in Compliance

Dr. Lissette Victorero, lead author and researcher for the Deep Sea Conservation Coalition (DSCC), remarked:

“In this study, we present independent analysis of bottom-fishing activities within the EU’s closures of VMEs. Our findings suggest that, while the 2022 closures have achieved an encouraging reduction in fishing activity, continued bottom-contact fishing within these fragile habitats reveals gaps in compliance and enforcement.

“These closures are an essential step in protecting some of the ocean's most vulnerable ecosystems, but ensuring their long-term success requires further mapping and protection of VMEs in EU waters and stricter adherence to regulations.”

Ongoing Threats to Fragile Habitats

While the reduction in fishing activity is promising, the study highlighted continued threats to VMEs. Of the 3,500 hours of post-closure fishing, Spanish vessels accounted for 1,769 hours, the most of any fleet, followed by Portuguese vessels. Three Portuguese bottom trawlers targeted a VME closure on the West Iberian Shelf, contributing over 500 hours of fishing effort in this critical area.

Short, quick incursions, such as those by Spanish vessels, often evade detection by vessel monitoring system (VMS) data. The study calls for enhanced surveillance using automatic identification system (AIS) data alongside VMS to improve transparency and ensure effective fisheries management.

"Bottom trawling is inherently destructive, removing important species including corals and sponges that provide key structure for many other species," states co-author Russell Moffitt of Marine Conservation Institute. "These habitat-forming species are often centuries old and require just as long to recover. For a 300-year-old deep-water coral, even a single trawl is too much."

Unprotected VMEs and Delayed Closures

The study also identified significant levels of bottom contact fishing in areas where VMEs are known to exist but remain unprotected due to prolonged political delays in implementing additional closures. In a two-year period, 19,200 hours of trawling were recorded at depths below 800 meters, despite the Deep-Sea Access Regulation banning such activities. These ongoing threats jeopardize the health and sustainability of VMEs across EU waters.

Bronwen Golder, Global Seamounts Campaign Lead at the DSCC, emphasized:

“The European Union’s leadership in protecting deep-sea ecosystems must be celebrated, with high levels of compliance identified by this study being an indication that EU member States are taking the collective protection of vulnerable marine ecosystems seriously.

“The reality of continued fishing activity by a handful of vessels in areas where the presence of VMEs has been confirmed sends a clear signal that the next phase of recommended VME closures under the Deep-Sea Access Regulation should be progressed without delay.”

A Call to Action

Twenty years ago, the international community, through the UN General Assembly (UNGA) and the Convention on Biological Diversity (CBD), recognized the immense value of deep-sea ecosystems and committed to protecting VMEs from destructive fishing practices. The EU’s recent closures mark significant progress toward fulfilling these commitments. However, effective monitoring and management are urgently needed to fully achieve the protection of VMEs from destructive practices.

The DSCC urges the EU to prioritize the continued implementation of the Deep-sea Access Regulation, including adopting new closures in 2025 to ensure all seamounts and VMEs in EU waters are protected.