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Fresh Thinking About FADs Published April 2024 Scroll Down ╲╱ Introduction Freely roving the world’s oceans, schools of tuna have long been a coveted prize for fishers. For a long time, humans have been refining their methods for luring and catching these fish. After observing that tuna aggregated around logs and other floating objects, fishers began launching their own contraptions made from various materials — and then monitoring them for fish to cast their nets. Using floating “fish aggregating devices” or “FADs” to aggregate tuna is a common fishing method. But FADs themselves have continued to evolve, particularly since the 1980s, as commercial fishing competition has intensified. FADs Are a Fact of Modern Fishing Pie Chart Showing 38% In 2018-2022, about 38% of the global tropical tuna catch (bigeye, yellowfin, and skipjack), or about 1.86 million tonnes each year, was caught with FADs. Both purse-seine and pole-and-line vessels make fishing sets on FADs. Read More Report Cover Image Questions and Answers About FADs and Bycatch This report answers key questions about Fish Aggregating Devices, or FADs — human-made floating objects used to aggregate tunas. Efficiency, But at a Cost Over time, fish aggregating devices — monitored by fishers for months at a time — have morphed into bulkier, industrial structures that typically include plastic, metal, and netting. FADs today also are tracked and equipped with sophisticated tools like echosounder buoys, which relay tuna-aggregation abundance information back to the vessel. On board, to decide which FADs to visit, skippers use geolocation, remote biomass estimates, satellite imagery for oceanographic cues, thermal current mapping, and other technologies. Conventional FADs have been highly efficient for catching tuna, and vessels have deployed them at sea in great numbers. But FAD productivity and proliferation have been damaging to ocean environments. Anatomy of a FAD FAD designs and materials have varied from era to era, region to region, and fleet to fleet. But the defining features are a surface or subsurface floating raft and a submerged tail structure. FADs can be anchored to the sea floor, but most drift with the currents and winds. Challenges Through heft, durability, and technology, modern FADs have “gotten the job done” for decades — enabling tuna fishers to harvest a healthy food for people around the globe. But all tuna-fishing methods have an environmental footprint. And when sustainable fishing is the goal, conventional FADs present significant challenges. FAD Fishing Challenges Transshipment Icon FADs can increase the possibility of vessels overfishing certain tuna stocks — that is, catching too many fish for the stock to remain at healthy levels. Transshipment Icon Marine animals that aggregate around tuna, including sharks and sea turtles, are at risk of becoming bycatch. They can be unintentionally caught by fishers making sets on FADs. They also can become entangled in FADs that are made with netting. Certain FAD designs and materials create an especially high bycatch risk for vulnerable species. Shark caught in net Transshipment Icon FAD structures left in the ocean after fishing can continue to ensnare vulnerable bycatch species over time, a process called “ghost fishing.” Transshipment Icon Those same unrecovered or lost FADs can pollute oceans … drift into reefs … and wash up on shores and beaches. Wherever FADs with non-biodegradable materials drift or sink, they persist in the marine ecosystem. Scuba divers untangle FAD remnants in the ocean Transshipment Icon RFMOs Are Empowered to Oversee FAD Use Regional Fisheries Management Organizations (RFMOs) and government agencies set rules for tuna vessels that use FADs to follow. But inadequate regulations, low vessel compliance, and lax oversight can magnify FAD fishing problems. Solutions Since 2009, ISSF scientists have traveled the world to research FAD materials and structures, impacts, and management firsthand, including on board tuna vessels. In research projects and workshops, our science team collaborates with fishers, peer scientists, oceanographers, and conservationists. ISSF scientists publish their insights and recommendations in ISSF reports and peer-reviewed articles and share their findings in tuna RFMO papers with fisheries managers. Biodegradable Is Better From our investigations, we’ve learned that to minimize their impacts on the marine ecosystem, FADs must be smaller, lighter, streamlined, and biodegradable — and not have netting, which can entangle sharks, turtles, and other marine creatures. Developing more sustainable “bio-FADs” is challenging, however. They need to function as effectively as conventional FADs and remain durable long enough to generate fishing opportunities. Ideally, biodegradable FADs also should be easy to retrieve and store when fishing operations end. A Return to Natural Materials Building a more sustainable FAD calls for substituting biodegradable materials for plastic-derived ones. Our “jelly-FAD,” for instance, can be made with bamboo canes, manila hemp or canvas, clay bricks, cotton rope, and other components, which can dissolve over time in the ocean if the FAD isn’t retrieved. The “Jelly-FAD” Difference ISSF’s current sustainable-FAD research centers on our “jelly-FAD” design, inspired by the neutral buoyancy of jellyfish. In many respects, ISSF’s jelly-FAD is a new take on the “original” traditional FAD: It’s built with nearly all organic materials. It doesn’t have netting. And it’s less bulky than conventional FADs. The jelly-FAD features a bamboo-and-canvas raft and a submerged, three-dimensional cube (drogue), which allows it to weather winds and currents. Because a jelly-FAD drifts slowly, it stays in the target fishing area longer and is more recoverable. Before and after deployment, it also folds conveniently flat for storage. Jelly FAD — A paradigm shift in Biodegradable Fish Aggregating Device (FAD) design This video shows ISSF scientist Dr. Gala Moreno teaming up with oceanographers to design and test biodegradable FADs as a more sustainable option for tuna fishing. Through brainstorming workshops, prototype trials, and other collaborations with fishers, ISSF scientists developed a sketchpad idea into reality. Since 2018, tuna fleets worldwide have partnered with ISSF to test various bio-FAD and jelly-FAD designs under real fishing conditions. Download the full infographic PDF to see research dates, participating fleets, and funders. Download the Infographic Discoveries ISSF has developed a jelly-FAD construction guide for fishers. We’re excited for more fleets to adopt the jelly-FAD — and help us to refine its design. Through research projects and workshops worldwide, our science team continues to listen to and learn from experienced fishers — a way of working that ensures FAD designs evolve to become more sustainable, with the key attributes of non-entanglement and biodegradability. But “rethinking the FAD” demands other changes beyond redesigning the physical device. ISSF examines the bigger ecological, industry, and policy picture of FAD fishing, too. And we share our findings and recommendations — with fishers and vessel owners, RFMO and government decision-makers, the scientific and conservation communities, and other stakeholders. Related ISSF Research Lightbulb icon To help tuna vessels fish more selectively and avoid accidentally catching other species, our scientists are studying how tuna, sharks, and other marine animals congregate and behave at FADs. Lightbulb icon We’ve also decoded tuna species “acoustic signatures,” which FAD echosounders can transmit to vessels. Fishers can use that information to discriminate which species are aggregating before they cast their nets — and then avoid catching overfished or non-target species. Echosounder data also helps fisheries scientists to evaluate fish stocks and FAD management. Scientist with acoustic equipment Lightbulb icon At ISSF skippers workshops with fishers, we identify effective methods for handling, releasing, and improving the survival rates of accidentally caught sharks, manta rays, sea turtles, and other bycatch species in FAD fisheries. Lightbulb icon We advise tuna fleets that want to earn or maintain Marine Stewardship Council fishery certification how to align their FAD management — including FAD reporting and retrieval — with sustainability best practices. Lightbulb icon To support seafood companies and vessels in being responsible stewards of the sea, we develop conservation measures for them to follow, spanning FAD design, vessel registration, illegal fishing prevention, and more. Lightbulb icon Through reports and other resources, we advise fishers and RFMOs about onboard electronic monitoring systems for observing, and credibly verifying, vessels’ fishing activities at sea. Lightbulb icon We’re studying how FADs drift in oceanic currents — knowledge that will help vessels to prevent their FADs from straying out of the fishing zone and getting lost at sea. Lightbulb icon And we’re putting tuna RFMO FAD-management policies under the microscope, and advocating more rigorous requirements for their fleets — on FAD data, time/area closures, biodegradable FAD adoption, and more. Scientist collaborate at an ISSF workshop FADs Icon FADs Have a Lot to Tell Us One interesting outcome of FAD use is our ability to gain a better understanding of marine ecosystems, including not only the effects of fishing activity but also the impacts of climate change on tuna stocks and ocean environments. As skippers share data with scientists from the echosounder buoys that are tracking FADs, for example, we learn more about tuna environmental habitats, behaviors, distribution, and abundance. That knowledge, in turn, makes the development of more effective conservation measures for seafood comanies and tuna vessels possible. Conclusion In our efforts to rethink how FADs are built, used, and managed so that tuna fisheries can become more sustainable, ISSF seeks and keeps “good company.” We partner with tuna fishers, global environmental NGOs, fisheries experts, and marine research institutes on FAD research, bycatch mitigation, and other projects. Our participating seafood companies and the vessels on ISSF’s PVR and VOSI vessel lists are leading by example and embracing leading-edge solutions in FAD management, bycatch mitigation, and more. And many of the changes ISSF has championed — such as non-entangling FAD designs and active-FAD limits per vessel — have become fleet requirements in four tuna RFMO regions. Research in Action Jelly-FAD Guide Cover Image Jelly-FAD Construction Guide Learn more from our step-by-step guide, published in April 2024, which shows tuna fishers how to build “jelly-FADs” — an effective and ecologically sustainable fish aggregating device (FAD) design.