The Problem of Drifting Tuna Fishing Nets
Marine protected areas (MPAs) may prohibit industrial fishing within their boundaries, but they cannot prevent fishing gear released elsewhere from entering them. A new global study estimates that fish aggregating devices (dFADs) used by industrial tuna fleets affect more than half of the world's marine protected areas.
Some of these devices travel thousands of kilometers before sinking or being washed ashore, where they can damage coral reefs, entangle wildlife, and leave coastal communities with the burden of removing the debris. Published in Science Advances in June 2026, the study combined fishing records, published surveys, an online survey of MPA staff and experts, and follow-up interviews to assess the global distribution, stranding, and impacts of dFADs in MPAs.
Why This Matters
The impacts of these devices are not only environmental but also social and economic. Coastal communities are affected by the presence of this debris, which can damage tourism and fishing infrastructure, as well as pose a risk to human safety. Furthermore, the loss of biodiversity and degradation of marine ecosystems can have long-term consequences for ocean health and food security.
“We were surprised to find that dFADs affect more than half of the world's marine protected areas and that impacts often occur thousands of kilometers away from the original fishing grounds,” said Boris Worm, co-author of the study and marine ecologist at Dalhousie University in Canada, in an email to Mongabay.
The Mechanism Behind the Drift of Tuna Fishing Nets
dFADs are floating platforms deployed by purse-seine fishing vessels - industrial boats that encircle schools of tuna with large nets - to attract skipjack (Katsuwonus pelamis), yellowfin (Thunnus albacares), and bigeye (Thunnus obesus) tuna. These devices carry satellite-linked buoys and echosounders that allow companies to track them and estimate the amount of fish below.
However, many of these devices are later deactivated, lost, or abandoned, making them susceptible to being carried by ocean currents and entering marine protected areas.
Broader Context
This problem is not new, but it has become increasingly severe due to the increase in industrial fishing and the use of more advanced technologies to locate and catch fish. Additionally, the lack of effective regulation and international cooperation has hindered the implementation of solutions to this problem.
Previous studies had already demonstrated the presence of dFADs in marine protected areas, but the current study provides a broader and more detailed view of the extent of the problem. This highlights the need for more effective actions to prevent the drift of tuna fishing nets and protect marine protected areas.
What Happens Next
The results of this study have important implications for the management of marine protected areas and the regulation of industrial fishing. It is necessary for governments and international organizations to work together to develop and implement effective solutions to prevent the drift of dFADs and protect marine protected areas.
Furthermore, it is essential to increase awareness about the importance of ocean conservation and the need for sustainable fishing practices. Education and awareness-raising among coastal communities and consumers are crucial to promote behavioral changes and support the implementation of more effective policies to protect the oceans.
Source / Reference
This article was originally published on Mongabay.