Fish aggregating device
A floating or anchored object that attracts open-sea fish, used to make tuna easier to find and catch.
Also: FAD
Fish gather under floating objects, from logs to seaweed, for reasons still debated. Fishers use this by setting fish aggregating devices: rafts with hanging netting, either anchored or left to drift, often with satellite buoys that report the fish beneath them. Tuna purse seiners set their nets around drifting FADs. They raise catches but also take many young bigeye and yellowfin tuna, sharks and turtles, and lost FADs end up on reefs and beaches. Tuna commissions now limit how many each vessel may use.