Trialing shark bycatch release devices on board purse seiners in the Pacific Ocean to enhance shark survival

Authors
Murua, H., Moreno, G., Murua, M., Grande, M., and V. Restrepo
Year
Journal/Publisher Name
Western and Central Pacific Fisheries Commission Scientific Committee Twenty First Regular Session
Volume (Issue #)
WCPFC-SC21-2025/EB-IP-12
Summary

This study evaluated the effectiveness of updated best handling and release practices, as well as a custom-designed shark release ramp, in improving the post-release survival of sharks onboard a U.S. purse seine vessel. 98.5% of sharks were released using the ramp system, with release times averaging under two minutes. 47% of captured sharks exhibited poor or moribund condition at haul-back. Tagging data from three released sharks indicated survival or likely survival post-release. While the ramp system with a hopper improved operational efficiency and enhanced crew safety, wider tagging efforts is needed to validate improved survivability of sharks post-release. 

Field Studies

Trialing shark bycatch release devices on board purse seiners in the Pacific Ocean to enhance shark survival

Study Type
Field study in the wild
Location
Western Pacific Ocean, American Samoa
Target catch
Tuna (species not specified)
Effect on bycatch species
47% of captured sharks exhibited poor or moribund condition at haul-back. Tagging data from three released sharks indicated survival or likely survival post-release.
Effect on target catch
Not studied