HONOLULU (17 October 2023) Today the National Marine Fisheries Service (NMFS) published a proposed rule to modify seabird mitigation measures for the Hawai‘i deep-set longline fishery managed under the Pacific Pelagic Fishery Ecosystem Plan of the Western Pacific Regional Fishery Management Council. The proposed rule is based on the Council’s recommended changes to replace the currently required blue-dyed bait and strategic offal discharge with a tori line, also known as streamer lines or bird scaring lines.

“The Council’s recommended changes were a result of a multi-year collaborative effort with fishermen, scientists, and fishery managers to improve techniques for avoiding seabird interactions in the largest domestic bigeye tuna longline fishery in the United States,” said Council Executive Director Kitty Simonds. “This is an example of the successful adaptive mangement process under the Magnuson-Stevens Act, and part of the Council’s long history of proactive conservation measures to address fishery impacts to protected species.”

The proposed rule will be open for public comment until Nov. 16, 2023. The proposed changes would only apply to Hawai‘i deep-set longline vessels that set their gear from the stern, and would not affect vessels that set their gear from the side (“side-setting”). All deep-set longline vessels would also continue to be required to use weights near the hook so that the hook sinks out of seabirds’ diving depth faster. If finalized as proposed, these changes may go into effect as early as mid-January 2024.

The proposed regulatory change reflects findings from a 2019-2021 collaborative project by the Council, Hawaii Longline Association (HLA) and NMFS. The focus of the project was to develop a practical and safe tori line specifically designed for the Hawai‘i deep-set longline fishery, which led to a design that is light-weight and streamlined. Field trials demonstrated that the newly designed tori lines are significantly more effective in deterring seabird interactions than the existing blue-dyed bait measure.

Blue-dyed bait and strategic offal discharge have been in place since 2001 as mitigation measures for tuna-targeting deep-set longline vessels when fishing north of 23°N latitude. The implementation of these seabird measures reduced interactions by 70-90%. Over time, seabird interaction trends in the fishery showed a gradual increase, and an analysis of federal observer program data for 2004-2014 showed that blue-dyed bait was less effective in deterring seabird interactions than the alternative option of side-setting. Fishermen also found the preparation of blue-dyed bait to be cumbersome and messy. A Council workshop convened in 2018 highlighted the need to find alternative mitigation measure to blue-dyed bait to improve the practicality of the requirements for the fishermen, and workshop participants identified tori lines as a candiate alternative for further testing in the Hawai‘i fishery. Available evidence on strategic offal discharge, meant to distract seabirds from baited hooks, also suggest that the measure is not likely having an effect on seabird interaction rates, and may potentially increase seabird attraction to fishing vessels over time.

The Council evaluated the results from the tori line project and other best available scientific information, and recommended the regulatory change in December 2021. In lieu of a regulatory requirement for strategic offal discharge, the Council also recommended best practices training on offal management be added to the mandatory annual protected species workshop for Hawai‘i commercial fishermen. Since its final recommendation, the Council, in collaboration with HLA and with support from the National Fish and Wildlife Federation and NMFS National Seabird Program, has been preparing Hawai‘i deep-set longline vessels for the anticipated regulatory change by building and distributing tori line systems.

For more information on the proposed rule and supporting materials, visit www.wpcouncil.org/dsll-seabird-proposedrule.