Entanglement in fishing gear is a major threat to whales. It can cause drowning and infections and impair their ability to swim or eat. According to the National Oceanic and Atmospheric Administration's 2022 West Coast Whale Entanglement Summary, there were 30 confirmed entangled whales off the coasts of Washington, Oregon and California, or off the coast of other countries and states but entangled in U.S. West Coast commercial fishing gear. Historically, little was known about the overlap between whales and crab gear along the West Coast, making it hard to set policies to reduce entanglements.
The research helped create a safer and more sustainable environment for both whales and fishermen, ensuring the long-term viability of the Oregon fishing industry.
That has changed in Oregon waters thanks to a team that included Oregon Sea Grant Extension's Leigh Torres and Amanda Gladics. The team took to the air in Coast Guard helicopters from 2019 to 2021 to map the location of whales. The researchers also surveyed for whales from NOAA ships. With these two efforts, they surveyed 17,400 miles of Oregon waters from 2019 to 2021, according to Torres. The team shared its findings with the Oregon Department of Fish and Wildlife (ODFW) to help it design new regulations, which the agency adopted in September 2020, to reduce entanglements.
The researchers developed models that connected ocean and climate conditions from 2011 to 2020 with sightings of humpback, fin and blue whales off Oregon. They then created maps of predicted whale densities for every month during this period. The team then laid these maps over Dungeness crab fishing locations during that period to determine where and when whales were most at risk of entanglement.
The findings suggest that risk is higher in nearshore waters, particularly in April when seasonal whale densities begin to increase while Dungeness crab fishing continues. Exposure was lower during the marine heatwave from 2014 to 2016 when whales were predicted to be less abundant because of poor ocean and prey conditions. This latter result was surprising because it differed from prior research on entanglement risk in California, highlighting the value of conducting regional assessments.
The research was in response to a need identified by a whale entanglement working group that we convened from 2017 to 2019 as part of Oregon Sea Grant's commitment to engage with fisheries communities to address emerging issues, improve socioeconomic resilience and ensure environmental sustainability.
The Oregon Whale Entanglement Working Group, convened by Oregon Sea Grant from May 2017 to July 2019, comprised various stakeholders, including fishermen, ODFW and environmental nonprofits. The working group developed the "Oregon Commercial Dungeness Crab Fishing 2017-2018 Directive to Minimize Whale Entanglement Risk," which outlines voluntary best practices aimed at reducing whale entanglements in Dungeness crab fishing gear.
In some cases, the source fishery of entanglements is not known, making it hard to design mitigation strategies. At NOAA’s request, Oregon Sea Grant organized and facilitated an online workshop in 2022 to inform a required feasibility study about making groundfish pot gear — like what's used in the sablefish industry — more identifiable and modifying it to reduce entanglements of protected humpback whales.
At the meeting, over 50 people, including 12 commercial fishing industry members, rated and prioritized ideas. Suggestions included using more permanent markings on buoys and attaching electronic devices to gear to signal its location. A summary report was sent to NOAA and to over 4,000 parties.
In June 2024, the Pacific Fishery Management Council adopted a final preferred alternative for gear marking and entanglement risk reduction measures for groundfish fixed gear fisheries.
By identifying times and areas where whales are most likely to get entangled, fishermen can avoid these hotspots, leading to fewer incidents of gear loss or damage caused by entangled whales. Fishermen can adjust their practices to minimize harm to marine life, supporting more sustainable and responsible fishing methods.
Overall, the project helped create a safer and more sustainable environment for both whales and fishermen, ensuring the long-term viability of the Oregon fishing industry.
