When to remove ghost nets – and when not: new study offers guidance

The study shows that ghost nets do not have a uniform impact: lost gillnets often continue catching and killing marine life unintentionally – also known as ghost fishing – while trawl nets typically stop fishing and can provide habitat over time. In some cases, nets both harm and support biodiversity, highlighting the need to assess ecological trade-offs in the process of deciding whether to remove ghost nets or to leave them in place.

Researcher Wouter Jan Strietman of Wageningen University & Research: “No ghost net is the same. And not all ghost nets are harmful to marine life. Sometimes, leaving them in place during clean-up operations can actually protect marine life. That is where informed decision making makes all the difference.”

From insight to action

Ghost nets are a major contributor to marine plastic pollution. They can trap marine life, damage habitats, and remain on the seabed or entangled around wrecks for decades. Addressing this issue therefore remains critical, and organisations such as the Healthy Seas Foundation and Ghost Diving have long played a leading role in removing such gear.

This study builds on that work by providing new insights and practical guidelines that help divers assess, in the field, whether to remove or leave a ghost net, based on whether it causes ecological harm or provides important habitat to (protected) species. The findings come from a scientific study commissioned by the Healthy Seas Foundation. Healthy Seas and Ghost Diving are now working to integrate the study’s findings into their operations, including diver training, field protocols, and stakeholder engagement.

Veronika Mikos of Healthy Seas: “We are committed to continuously improving our impact. This study provides valuable tools to help us take the next step: ensuring that future clean-up activities remain both effective and environmentally responsible, supported by a strong ecological understanding.”

More information

• The report: Ecologically informed decision-making for ghost nets from shipwrecks and the seabed in the North Sea and Adriatic Sea using scuba diving.

Text: Isadora Abuter, Healthy Seas & Wageningen University & Research
Images: Cor Kuyvenhoven; Erik Wurz