Progress report on the development and testing of the underwater bait setter for pelagic longline fisheries

This paper summarises recent research and future improvements relating to the development, construction and testing of a device that sets hooks up to 10 m underwater to avoid detection by seabirds. The underwater setter is a stern-mounted, hydraulically-driven device. The baited hook is placed into a capsule that is driven down into the water column each time a hook is set; the baited hook is subsequently released from the capsule while underwater. This design provides a more fuel efficient method than devices that remain underwater while setting (e.g., underwater setting chutes). The device can be readily fitted to most tuna fishing vessels, including after their construction.