Credit: Emrith Vinesh (Mauritius)
This structure shown in the photo which was introduced in 1985 is known as a Fish Aggregating Device. Fish aggregating devices (FADs) are floating objects that are specifically designed and located to attract tunas, and therefore allow fishers to find them more easily. No one understands exactly why tunas are attracted to FADs.
The aim is to relocate the artisanal fishermen from the heavily exploited lagoon areas to the open sea, with a view to increasing their catch and concurrently reducing fishing pressure in the lagoon.
The Fish Aggregating Devices (FADs) designed in Mauritius is composed of reinforced plastic floats mounted on two strings of polyamide rope and moored to the sea bed with polypropy-lene rope. 27 FADs have been set around the island at distances of 3 to 10 nm from the shore and at depth ranging from 400 to 3 000 m.
Deep-water FADs attract or aggregate Skipjack (Katsuwonus pelamis), Yellowfin (Thunnus albacares), and Bigeye tunas (Thunnus obesus) and also sharks, Dolphin-fish, Rainbow-runner and other smaller fish.
No one understands exactly why tunas are attracted to FADs, but the ropes, floats and the other materials used presumably mimic the build-up of driftwood and seaweed found naturally in the sea.
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