An Evaluation of International Policies and Local Management Strategies to Reduce Marine Mammal Bycatch

Zusammenfassung

Bycatch, the incidental capture of non-target species in active fishing gear, is the most significant human threat to coastal marine mammals and a severe conservation problem. Characterizing the effects of bycatch through space and time is similar to finding a needle in a haystack: relatively small populations and limited interactions with dispersed fishing vessels. The behaviors of both parties are unpredictable, and therefore a challenge for researchers to collect data and managers to effectively manage. Further adding to the problem, a lack of risk frameworks that can integrate and visualize existing datasets has hindered the ability to describe and quantify bycatch risk. There are spatio-temporal patterns in bycatch occurrence that can be identified, even in data-limited SSF. Therefore, is it possible to design and apply an assessment framework for evaluating harmful interactions between marine mammals and fisheries using existing information only? This is the main question I attempt to answer in this thesis. This is a knowledge gap worth exploring because ocean data and the systems developed to monitor marine ecosystems are now more sophisticated and cheaper to deploy. More broadly, I investigate the ways in which international policies have, or have not, translated into effective management strategies for the monitoring and mitigation of marine mammal bycatch in data-limited fisheries.