Development and Large-Scale Testing of a Low-Cost Acoustic Release System used to Reduce Entanglement Risk in Commercial Trap Fisheries

Whale, dolphin and turtle entanglements in fishing gear continue to be a problem on a worldwide scale. Conflicts occur most often in areas with high concentrations of marine mammals in waters also having high concentrations of traps, pots, or gillnets. According to the National Oceanic and Atmospheric Administration's (NOAA's) National Report on Large Whale Entanglements Confirmed in the US in 2022, there were 67 confirmed whale entanglements off US coastlines, with the greatest number of cases being found near Cape Cod Massachusetts and Monterey Bay California. In recent years, significant development and testing of new on-demand or rope-less fishing technologies have been reported, including a low cost Timer Release for Rope-less Traps (TR4RT) by Sub Sea Sonics, funded under a NOAA Bycatch Reduction Engineering Program Grant and presented at the 2021 Oceans Conference in San Diego. The TR4RT release was developed as a solution for small scale and inshore fishing boats needing a simple and affordable option for single traps or small trawls in contrast to the complex high-cost acoustic release systems geared toward offshore boats fishing long trawls with a large number of traps. Based on feedback from fishers, we developed an on-demand acoustic version of the same timer system (the Acoustic Release for Rope-less Traps; AR4RT) under support from the NOAA Saltonstall-Kennedy program and Woods Hole Oceanographic Institution. The AR4RT utilizes a motor turn cam release combined with Sub Sea Sonics proven underwater acoustics technology with a 20 year track record. It can be mounted directly on a fishable trap or fitted on a trawl sled. The AR4RT releases system has been successfully used in time area closures on both coasts of the US including in the Southeast (SE) Atlantic Black Sea Bass fishery in a project lead by Sustainable Seas Technology (SST) where the South Atlantic Fishery Management Council is now moving toward making pop-up gear allowable following closure to protect the North Atlantic Right Whale. Recently, a full-scale test was carried out under a California Experimental Fishing Permit for Dungeness Crab, Rock Crab, and Hagfish with 20 fishers purchasing gear to participate. The AR4RT release units were used with Guardian Ropeless Systems (GRS) line handling equipment to remove vertical lines in the water column and allow crab to be harvested for almost 3 additional months after the regular season closed due the presence of whales. Fishers use our Trap Timer gear marking app to display gear locations and transmit corresponding acoustic commands to the underwater releases. We also developed a regulator version of the app and web portal which allows the California Department of Fish and Game and other enforcement agencies to both view and haul subsurface fishing gear. Testing is also being conducted in the New England lobster fishery by the NOAA Northeast Fisheries Science Center and Maine Department of Marine Resources with a handful of fishers using AR4RT and Deepwater AR4RT releases off Maine, Massachusetts, and Rhode Island, and specifically within the South Island Restricted Area. Partnering with both SST and GRS, scaled up outreach, gear refinements (including updates to the DAR4RT) and testing will take place in New England starting in 2024 with support from the National Fish and Wildlife Foundation.