Ecosystem-level impacts of fisheries bycatch on marine megafauna: biodiversity conservation through mitigation, policy, economic instruments, and technical change

The selectivity of fishing operations is such that despite the sustained efforts made during the last decades to reduce it, the accidental capture of living marine resources (bycatch) sometimes followed by their discarding at sea1 remains an important point of friction between fisheries and biodiversity governance systems, particularly when emblematic, endangered or particularly vulnerable species are concerned. Bycatch reduction practices have traditionally focused on command-and-control measures (e.g., time-and-area closures, effort reduction) or technology standards and associated legislative changes (e.g., mesh size, hook types, bycatch excluder devices, and mandated requirements that freeze technology in place). Incentive-based bycatch reduction practices such as use rights (e.g., Dolphin Mortality Limits, DMLs), taxes, credit schemes, or insurance, may more directly and cost-effectively reduce bycatch. This approach has received insufficient attention.