I often get guys asking me, what does a FAD look like, how do you construct one & how does it work? Definitions first.
FAD stands for Fish Aggregating / Attracting Device & refers to any man-made object used to attract fish in open water. Basically, an FAD is like an artificial reef where bait-fish congregate and in turn, attract larger fish from further up the food-chain. They are used by both recreational and commercial fisheries.
I have attached a photo of a typical Malaysian FAD above. These FADs are pretty much like the local 7-eleven stores in Malaysia or ABC stores in Hawaii for predatory fish to stop in and catch a bite!
In Malaysia, FADs are known as “unjang” and are traditionally made using criss-crossed vertical bamboo poles harvested from the rainforest tethered with palm leaf structures underwater. FADs in Malaysia today still use palm leaves (usually coconut palms as they last longer than oil palms) tied to long ropes and weighted down with rocks, artificial cement-filled drums or blocks– basically anything heavy; even your mother-in-laws old furniture would serve the purpose– with large empty plastic containers tied together and floating on the surface to act as indicators. The FADs in Malaysia can be the size of a basketball or badminton court. The larger /older FADs hold and attract more fish, and it may take between 2 - 4 weeks for a new FAD to start attracting big fish.
Before the use of FADs, commercial tuna fishermen relied on spotting aggregations of birds and dolphins on the surface– a reliable indicator of schools of tuna below. On arrival at these spots, the fishermen used nets to indiscriminately haul up the schools of tuna along with any other marine creatures that happened to be in the way. (Remember that nail-biting scene from "Finding Nemo”? Like that.)
The demand for dolphin-safe tuna was a driving force behind the use of FADs, and increasing use of FADs over the past 30 years has increased the productivity of commercial fishing fleets. Nearly three quarters of the world’s tuna fisheries use FADs but with the side effect that the fish tend to be smaller (many are still juveniles) and there is also concern about by-catches of turtles and endangered shark species. Not surprisingly, Greenpeace has voiced strong objections to FADs.
Fish are fascinated with floating objects the same way women are fascinated with shiny stones, and FADs provide what has been described as "a visual stimulus in an optical void” (see "Association of fishes with flotsam in the offshore waters of Central America". US Fishery Bulletin, Hunter, JR and Mitchell CT, 1966).
Fisher(men) have been taking advantage of this fact since biblical times, casting their nets or dropping their lures near floating logs, drifts of seaweed and other natural debris. The fish also use floating objects to mark the locations of their amorous mating activities, since FADs offer protection from predators for their newly hatched offspring.
In Malaysia, FAD’s are established independently by commercial fishermen without government regulation, but FADs in other parts of the world are banned because they pose a serious threat to boats, especially at night. In places like Hawaii, FADs are operated by the state, and carefully regulated and monitored. The U.S. state of Hawaii operates 55 surface FADs around its islands to support recreational fishing and marine research, and the results of this research are used to improve resource management and develop sustainable fishing practices worldwide.