Kobe II Bycatch Workshop - Marine Mammal

The bycatch of marine mammals in fisheries is a significant factor in long-term conservation and management of marine mammal stocks worldwide. It is estimated that tens to hundreds of thousands of these animals are killed each year through entanglement in fishing gear. Marine mammals interact with several gear types used in fisheries managed by tuna RFMOs. They are most commonly caught in purse seine, longline, and gillnet gear. With the exception of the EPO, accurate abundance and bycatch estimates for marine mammals are lacking in areas where marine mammal distribution overlaps tuna fisheries, making quantitative analysis of bycatch extremely difficult. Progress in quantifying tuna RFMO fishery impacts on marine mammal populations and related progress in mitigating or reducing the mortality has been slow, sporadic, and limited to a few specific fisheries or circumstances.
One notable exception is the work of the IATTC in conjunction with the AIDCP. The IATTC and AIDCP have extensive information on marine mammal populations, distributions and bycatch rates in IATTC purse seine fisheries and have adopted effective measures for reducing dolphin bycatch. In contrast, the remaining tuna RFMOs lack marine mammal population and bycatch data and, as a result, have not determined whether there is a need to adopt bycatch reduction measures for these species. In fact, much of what is known about marine mammal bycatch in fishing gear used by tuna fisheries has not been discussed by the RFMOs. Still, the data that exist within tuna RFMOs, their member nations, and other sources provide a suitable foundation for tuna RFMOs to begin discussions of how best to assess and address the conservation of those species of marine mammals that interact with high seas tuna fisheries.
The combination of a lack of information in most tuna RFMOs and a depth of expertise, understanding and reducing marine mammal interactions in purse-seine fisheries, offer opportunities for tuna RFMOs to closely collaborate with one another and with key IGOs to design and implement data-gathering programs. Working with these organizations, tuna RFMOs could also develop and adopt, if necessary, bycatch reduction measures, and monitor the effectiveness of, and compliance with, those measures.