Effect of fish aggregating devices (FADs) on catch and stock biomass: A mean-field model

Abstract

Fish aggregating devices (FADs) are utilized to aggregate fish over a small area, which makes harvesting fast and efficient. However, the impacts of utilizing FADs are not yet well understood. We created a mean-field model to assess the effects of utilizing FADs on stock biomass and boat’s catch under various fishing preference towards FADs. Our results indicate that using FADs can be beneficial, but when effort is excessive, it can exacerbate fishery collapse. A quota-based fishery system, where a catch quota drives fishing time, can produce a phase transition where catch and biomass levels abruptly shift to low levels without caution.