Over the past three decades, FADs became especially popular in commercial fishing fleets, partly as an unintended consequence of the movement to save dolphins. These fleets used to find tuna by looking first for dolphins, which often followed and swam near the surface above tuna schools because it helps them ward off predators. This approach led to hundreds of thousands of dolphins being inadvertently killed as bycatch when they were netted with tuna. In the 1980s and 1990s, the demand for “dolphin-free” tuna pushed many fleets to relocate.
