By-Catch

Bycatch is the portion of a catch taken incidentally while targeting other species, including non-target fish, juveniles, marine mammals, sea turtles, and seabirds. It drives population declines in slow-reproducing species and wastes biomass through discarding. Mitigation centers on gear modification: turtle excluder devices (TEDs), required in US shrimp trawls since 1987 and about 97% effective at excluding turtles, plus bycatch reduction devices (BRDs), circle hooks on longlines, and acoustic pingers on gillnets. The EU Common Fisheries Directive landing obligation and the US Marine Mammal Protection Act bycatch limits set the regulatory framework.