FAD's are a man-made fish-aggregating device used by the fishing industry to attract tuna and other ocean going pelagic fish. FAD’s pitch and roll with the coming of swell in all our great tropical oceans and seas. They’re can be made from bamboo, steel drums, ropes, chains, nets, logs, buoys and any other floating objects, in some cases tethered to the ocean floor with steel cables and concrete blocks, five kilometers down.