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Gear modifications for bycatch reduction

In the U.S. Pacific halibut fisheries, yelloweye rockfish (Sebastes ruberrimus) bycatch is an issue as their stock status along the West Coast is “rebuilding” from being overfished (NMFS, 2019), while the SE Alaska stock is at low levels compared to those observed in the mid-1990s (ADFG, 2020, NPFMC, 2021). The IPHC has participated in collaboration with Pacific States Marine Fisheries Commission in studies designed to evaluate different strategies for the reduction of yelloweye rockfish bycatch in the directed Pacific halibut longline fishery. The first strategy consisted in testing the effect of circle hook size and circle hook modifications through the incorporation of appendages at a 45o angle. The results from this study indicated that hook size did not significantly affect the catch efficiency of Pacific halibut and yelloweye rockfish. Most interestingly, the results from this study suggested that hooks with appendages caught significantly fewer yelloweye rockfish than regular circle hooks (Lomeli et al., 2023). The second strategy consisted in investigating whether semi demersal longline gear could be more effective than demersal longline gear at reducing yelloweye rockfish bycatch while maintaining its efficiency to capture Pacific halibut, as yelloweye rockfish tend to be captured less by non-demersal fishing gear. Data from this study are still being processed at this time.


Alaska Department of Fish and Game (ADFG). 2020. 2021 demersal shelf rockfish fisheries. DSR Fisheries Announcement December 31, 2020.

Lomeli, M.J.M., Wakefield, W.W., Herrmann, B., Dykstra, C.L., Simeon, A., Rudy, D.M., Planas, J.V. 2021. Use of Artificial Illumination to Reduce Pacific Halibut Bycatch in a U.S. West Coast Groundfish Bottom Trawl. Fish. Res. 233: 105737.

Lomeli, M.J.M., Wakefield, W.W., Abele, M., Dykstra, C.L., Herrmann, B., Stewart, I.J., Christie, G.C. 2023. Testing of hook sizes and appendages to reduce yelloweye rockfish bycatch in a Pacific halibut longline fishery. Ocean & Coastal Management. 241: 106664.

National Marine Fisheries Service (NMFS). 2019. Status of U.S. Fisheries. Summary of stock status for FSSI stocks.

NPFMC (North Pacific Fishery Management Council). 2021. Assessment of the demersal shelf rockfish stock complex in the Southeast Outside Subdistrict of the Gulf of Alaska. North Pacific Fishery Management Council, Anchorage, Alaska.



In this Section

Migration and Population Dynamics

Generation of genomic resources

Fishing technology

Discard survival assessment in the guided recreational Pacific halibut fishery

Discard survival assessment in the commercial Pacific halibut fishery

Economic Research

Management Strategy Evaluation

Stock Assessment

FISS – Catch Per Unit Effort

Vessel Recruiting

In this Section

Design and Implementation

IPHC Fishery-Independent Setline Survey (FISS) The purpose of the FISS

Biological and Ecosystem Science Research

Since its inception, the IPHC has had a long history

Tag Recovery and Reward

A reward of a hat or $10 is offered for most recovered

Non-directed Commercial Discard Mortality

Pacific halibut are captured in large numbers by vessels fishing