Summary
This study summarized trends in United States marine mammal bycatch from 1990-2017. Total annual bycatch was estimated to be 4296 ± 1789 individuals, and the vast majority occurred in gillnets; 52% of marine mammal bycatch consisted of pinnipeds, while the other 48% was cetaceans. Total marine mammal bycatch in U.S. fisheries declined from 1990 to 2002 following the passage of the Marine Mammal Protection Act in 1972, but there was no change in total bycatch from 2002 to 2017, suggesting that U.S. bycatch mitigation measures has had some success. While bycatch levels declined through 2017 in the Atlantic-Gulf of Mexico-Caribbean region, reductions either halted or increased in the Pacific and Atlantic regions by 2006.