Project Summary

This report summarizes the spring 2025 results of an Experimental Fishing Permit (EFPT2-001) to test Alternative Gear in the California Dungeness crab fishery. The EFP tested a fully integrated on-demand fishing system from Sub Sea Sonics and Guardian Ropeless consisting of the following components:

•Sub Sea Sonics AR4RT/AR4RT+ Acoustic Release Units

•Sub Sea Sonics ARI-U Universal Acoustic Deck Unit with Transducer

•Guardian Ropeless Line Handling System variants with required lines and floats

•Second End and Grapple Backup Systems

•Traps run in strings (trawls) with a minimum of 2 traps per string

•Sub Sea Sonics Trap Timer Virtual Gear Marking App

•Sub Sea Sonics Ropeless Regulatory Portal

•Vessel Electronic Monitoring System

•Training and Certification Program

•rmwHUB interoperability system

Extensive testing of the system was conducted during the spring of 2025 under EFPT2-001 in the California Dungeness crab fishery. Significant testing was also carried out under the same EFP during the spring of 2023 and 2024. Previous testing was also carried out using single traps and the timed version of the release system (TR4RT) during 2021 in the California Dungeness crab fishery. Large-scale testing of the system has also been carried out in the Northeast US in conjunction with the NOAA Northeast Fisheries Science Center. In addition, significant testing of the system was conducted using single traps and the acoustic version of the release system in the California Spiny Lobster fishery and the Southeast US Black Sea Bass fishery during the winter of 2022-2023.

Results from AR4RT/Guardian system testing under EFPT2-001 during the spring of 2025 provide the most extensive and realistic measure of the system performance for the gear that is targeted for authorization. Although 39 authorized agents signed up for the EFP, only 12 participated due to the perception of low crab abundance during the traditional season. Twelve authorized agents and 12 vessels participated in the testing (Table 1). This included 1 vessel operating from San Francisco, 3 vessels operating from Bodega Bay, 4 vessels operating from Half Moon Bay, 1 vessel operating from Santa Cruz, 1 vessel operating from Moss Landing, 1 vessel operating from Morro Bay, and 1 vessel operating from Crescent City. All of the vessels except the Areona in Santa Cruz were equipped with the AR4RT/Guardian Sleds with 10-15 strings of 10-50 traps each. The Areona was equipped with AR4RT/Guardian Trap-Top Retrofits. Following training, the combined fleet of participants conducted a total of 1163 gear sets during the period from 4/20/25 – 7/13/25. All testing was conducted under actual fishing conditions and allowed for retention and sale of catch.

The total number of traps set during the trials was 25721. The trials were carried out over approximately 123 individual trips.

Locations of the gear during the trials were focused on the fishing grounds offshore from Point Arena (Zone 2), Bodega Bay/San Francisco (Zone 3) Santa Cruz/Monterey (Zone 4) and Morro Bay (Zone 5). Deployment depths ranged from 27 – 392 ft with an average of 163 ft. Wave heights ranged from 2.2 – 12.7 ft with an average of 5.4 ft. Wind speeds ranged from 0.0 – 27.2 kts with an average of 6.6 kts. Overall, the release system (AR4RT/AR4RT+) was successful in about 98.7% of the tests, the line handling (Guardian) was successful in 99.7% of the tests, and the overall success rate of the on-demand system was found to be 98.4%. When the on-demand system did not work, going to the second end popup (if available) or grappling was generally effective as a backup method. Including the use of the second end, the reliability improved to 99.2%, and including the use of the second end and grappling the reliability was essentially 100% (all strings were recovered) although a few individual traps were lost. Loss rates for gear was about 0.2% with 7 traps lost out of the 3760 that were used. A preliminary estimated total of 234504 pounds of Dungeness crab were landed by the participating vessels, indicating an average catch of about 19542 pounds for the 12 participating vessels. Note that this estimate is preliminary and based on fisher reporting to the EFP program. Preliminary total landings based on landings reported directly to the California Department of Fish and Wildlife (CDFW) were 217633.65 pounds with a total value of $1,425,136.52.

Data