This project proposes to test two recompressing methods for commercial longline caught rockfishes, quantify the rockfish survival rates given their on-hook duration, and develop survival credit tables

The National Oceanic and Atmospheric Administration awarded a $243,797 cooperative agreement to the Pacific States Marine Fisheries Commission on July 15, 2026, under the Cooperative Research Program (CFDA 11.472) to test recompression methods for commercial longline-caught rockfishes and develop survival credit tables.

The project will evaluate two recompression approaches. The first involves a downrigger or davit extending from a vessel's stern, where captured rockfish are clipped to weighted SeaQualizer descending devices (pressure-triggered release mechanisms) and lowered to depth during the longline haulback process. The second method holds rockfish on deck in steel cages within full-sized fish totes with running seawater during capture, with each cage holding approximately 100 fish; after haul-back completion, cages are transferred to the vessel's port or starboard side and lowered to depth using hydraulic pot haulers. A subset of fish in recompression cages will remain on the seafloor for 48 hours to recover and be reexamined for barotrauma symptoms, allowing researchers to calculate post-recompression survival rates by species and quantify survival given on-hook duration.

Work is performed in Portland, Oregon, with a period of performance ending January 31, 2028. The Cooperative Research Program facilitates partnerships between the fishing industry, fishermen, and federal and university scientists to collect fisheries information supporting single-species, multispecies, and ecosystem assessment models.

The first recompression method tested would consist of a downrigger or davit extending from the vessels stern. Captured rockfish are clipped to a weighted seaqualizer descending device (noninvasive commercially available release devices that are triggered by pressure) then clipped to the downrigger cable with a snap, descended, and released at depth during the longline haulback process. The second recompression method would involve on-deck holding where rockfishes would be held in a steel cage within a full-sized fish tote with running seawater as they are captured throughout the longline haul-back process. Assuming we only fill the tote half full with fish, each cage should be able to hold approximately 100 fish. Therefore, multiple totes, each with their cage, would be available on the vessel. After the longline hauling operation is complete, the cage would be lifted from the tote using the vessel's lifting boom, transferred to the vessels port or starboard side, and then lowered to depth using the vessels hydraulic pot hauler. A subset of rockfishes would be placed into recompression cages to simulate recompression while being able to assess fish health at a later date. The fish would be left on the seafloor for 48 hours to recover and reexamined for barotrauma symptoms. The duration of 48 hours was selected as is the length of time used by the pfmc to develop survival credits for recreational fishers. Using the data from the recompression cages the researchers would calculate the post-recompression survival rates for each species.