The Jelly-FAD: new results on its performance

Citation
Moreno G, Zudaire I, Uranga J, et al (2023) The Jelly-FAD: new results on its performance. In: IATTC - 7th Meeting of the Ad Hoc Working Group on FADs. IATTC FAD07 3rd Party doc, La Jolla California USA
Abstract

Fishers and scientists in the three tropical oceans are investigating different designs of biodegradable FADs (bio-FAD) efficient for fishing. The tactic followed by most fishers is to maintain the same conventional drifting FAD (dFAD) design (submerged netting panels hanging from the raft) but made of organic ropes and canvas (e.g., cotton, yute, abaca, etc.). Results of those experiences show that the lifetime of bioFADs that maintain the conventional dFAD design but made of organic materials, is shorter than that required by most fishers. The short lifespan of those bio-FADs is due to the structural stress suffered by dFAD designs conventionally used. We present the Jelly-FAD, a new concept on bio-FAD design that mirroring jellyfish, drifts with quasi-neutral buoyancy, which reduces (i) the structural stress of the FAD at sea and (ii) the need for additional plastic flotation. The jelly-FAD is not necessarily a fixed design; it is more of a change in the concept of conventional dFAD construction. The present document aims at summarizing the trials by Ugavi fleet in the eastern Pacific Ocean (EPO), in which Jelly-FADs are being used successfully, aggregating tuna with average catches of 44.1 tons. Jelly-FADs drift with similar speeds as conventional dFADs do or slower. Average and maximum monitored lifespan were 5 and 11 months respectively. Note that the lifespan was inferred from the visits or sets done, some jelly-FADs were redeployed after the set, so those FADs could still be drifting at sea. Finally, recommendations to reduce the impact of dFAD structures on the ecosystem and for bio-FADs construction and use are provided.