Testing biodegradable materials and prototypes for the tropical tuna fishery on FADs

The purse-seine FAD fishery is currently the most important way to capture tropical tunas in the EPO. FADs are a very efficient way of fishing; yet, as most fishing methods, they may also have negative effects on species and ecosystems, such as entanglement of sensitive species, contribution to marine debris and pollution or stranding events in vulnerable habitats. To address these potential effects, the IATTC staff was required to present recommendations based on science that would help in transitioning from traditional to biodegradable FADs, which are expected to reduce those impacts. The European Union granted the IATTC funds for a two-phase project involving experiments with biodegradable non-entangling FADs in both a controlled (phase 1) and real-fishing conditions (phase 2). Phase 1 provided information on the selection of biodegradable materials to be used in the construction of three different prototypes in phase 2. Phase 2’s work plan included several activities, including the design of prototypes (NEDs), the identification of collaborators and participants, the construction of the NEDs, the development and agreement of an experimental design, the monitoring and tracking of the experimental FADs, as well as the data collection and analysis. 379 NEDs (56 prototype 1; 255 prototype 2; 68 prototype 3) have been deployed. Similar values in catch per set (NEDs = 27.7 t/set, paired control FADs = 26 t/set; Table 1) were observed. Prototype 2 showed a very good condition with two months of soak time. Prototype 1 showed a poor condition in the submerged rope, but the rest of materials appeared in good condition after two months at sea. Prototype 3 was the NED design with the least durability observed. The future actions, challenges and solutions of the project as well as ways to engage with the industry and fishers to obtain feedback and guarantee the correct functioning of the project are described as well.