Briana Abrahms, UW Biology Assistant Professor, was quoted in a news story by the National Oceanic and Atmospheric Administration Fisheries on research discussing how to best prevent whale entanglement in crab pots.
Researchers show that many strategies are insufficient during prolonged, anomalous warm water events called marine heatwaves. Instead, they recommend combining several approaches, including improved forecast systems, technological innovations, and understanding human behavior.
Over the past few years, marine heatwaves have dramatically affected natural resources along the U.S. West Coast, including economically valuable fisheries. Still, we know very little about how and when management actions can dampen their impacts on marine life and the people who rely on the ocean for their livelihoods.
An ecological pileup of recent unprecedented changes in the ocean off the West Coast led to record numbers of reported entanglements of humpback and other whales. These conditions put California’s Dungeness crab fishery, the region’s most valuable commercial fishery, at odds with the conservation of several at-risk whale species.
Previous research looked into some of the ecological causes and effects of the spike in reported whale entanglements. Now researchers are asking how to approach this problem by balancing tradeoffs between a profitable and sustainable fishery and whale conservation.
The researchers rewound the clock to understand how the marine heatwave affected fishing behavior and whale habitat. First, they looked back at how fishermen responded to the marine heatwave and associated fishing regulations. Second, they developed models to understand how whales responded to the extreme ocean conditions. They then used that past experience to explore a broad suite of potential solutions that could be implemented in the future.
“Knowing what we know now, we can consider how fishing vessels and the whales adjusted at the time and use that to evaluate possible solutions,” said lead author Jameal Samhouri, Ecosystem Science Program Manager at NOAA’s Northwest Fisheries Science Center.
Researchers say this extreme climate event made “win-win” solutions for protecting whales and fishing activity harder to find than they are during more normal conditions. “This example shows how climate change exacerbates the difficult tradeoffs managers have to weigh,” said Briana Abrahms, a coauthor from the University of Washington.
“As challenging as the marine heatwave was, there remains a lot to be learned from it,” continues Abrahms. “Understanding the role that climate extremes play in balancing the needs of people and species conservation can help anticipate and plan for those tradeoffs in the future.”