Addressing key research to inform Mobula rays conservation in the Pacific Ocean

Moreno G, Murua J, Cronin M, et al (2022) Addressing key research to inform Mobula rays conservation in the Pacific Ocean. In: WCPFC Scientific Committee 18th Regular Session. WCPFC-SC18-2022/EB-IP-16, Electronic Meeting

The habitat preference of Mobulas to productive tropical and subtropical habitats where tropical tunas also aggregate, increase their vulnerability to purse seine fishing. However, the rate of interaction of purse seine fishery targeting tropical tuna, with the different Mobula ray species has not been quantified in detail, especially in the western and central Pacific Ocean. One of the difficulties found to understand and quantify this interaction is the identification of Mobulas at the species level by the crew and observers onboard purse seiners. It is also necessary to evaluate the impact of handling and release methods, assessing Mobula post-release mortality. This project aims at addressing key research to inform Mobula species conservation with the collaboration of the U.S purse seine fleet. Due to the extensive spatial and temporal coverage of U.S. purse seine vessels that operate in the Pacific Ocean, those vessels represent ideal platforms to collect information on Mobula spp. interactions, test handling and saferelease best practices learned for Mobulas and collect tissue samples to ascertain their population structure across the Pacific. Lesson learned from applying current protocols and practices will allow developing improved best practices to be implemented by the US fleet which could be scaled to other fisheries and nations in the longer term.