Fish Aggregating Devices (FADs) are floating materials, either natural (such as logs) or manmade, which help to attract fish. They can be anchored to the seafloor using a weight or are attached to buoys and drift. There is a difference between ‘artisanal’ FADs, which tend to be anchored near boats or canoes in small-scale and subsistence fisheries; and ‘industrial’ FADs, which are mostly drifting, set far from shore, and used in commercial fisheries. Industrial FADs are commonly used in pelagic tuna fisheries to increase target catch.
The way in which FADs are designed and constructed can have implications on the risk they pose to marine wildlife. Sea turtles and sharks – particularly silky and oceanic white tips – can become entangled in the webbing that is often attached to the rafts used in industrial FADs, leading to mortality. However, FADs can be designed and managed to reduce entanglements of non-target wildlife species through a range of measures, such as pre-estimating likely interactions, using alternative designs and biodegradable materials, adjusting fishing time to account for seasonal wildlife behaviour, and using stimuli to draw non-target species away from FADs.
There are various options for managing and designing FADs to reduce non-target wildlife bycatch. A number of research projects have investigated non-entangling FADs, finding that the surface structure should be left uncovered, or covered with non-meshed material, in order to reduce entanglement on non-target species. In the case of turtles, cylindrical or spherical floating objects, placed on the surface of FADs, have been found to deter turtles from climbing on top. Sub-surface components should be made from non-meshed materials, such as canvas sheets, to avoid entanglement.
Another option is to attract sharks away from FADs. A pilot study found that sharks could be lured hundreds of meters away by towing a bag of bait away from the FAD. However, responses amongst sharks varied greatly. ‘Escape panels’ (large windows in the netting) are being tested as an option to release entangled sharks from FADs.
ISSF has produced a guide for best practice in managing bycatch around FADs.
This page was last updated on 12.02.21.
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