Uploaded March 2026 | Updated September 2026, 1 week ago
The Salish Sea, an inland waterway in Washington State, supports diverse shellfish species harvested for commercial, recreational, subsistence, and cultural purposes. As the nation’s largest producer of farmed shellfish, Washington contributes over 3,200 jobs and $270 million annually to the economy. However, summer shellfish die-offs have been reported for nearly a century, with limited success in mitigation. In 2016-2017, a major mortality event revealed yessotoxin, produced by harmful algae, at levels of 2.20 mg/kg in shellfish—enough to cause die-offs. From 2021-2023, researchers found yessotoxin levels ranging from undetectable to 2.36 mg/kg, with all South Salish Sea samples containing quantifiable levels. This highlights a stronger link between yessotoxin exposure and shellfish die-offs than previously recognized. As climate change, urban runoff, and drought increase biotoxin risks, these findings emphasize the urgent need to protect food security and sovereignty for communities relying on shellfish as a dietary staple.
The Environmental Speaker Series is free and open to the public. Talks are held each Thursday at 4:30pm in Academic Instructional Center West, room 204. Join us at WWU or online on Zoom!
The Salish Sea, an inland waterway in Washington State, supports diverse shellfish species harvested for commercial, recreational, subsistence, and cultural purposes. As the nation’s largest producer of farmed shellfish, Washington contributes over 3,200 jobs and $270 million annually to the economy. However, summer shellfish die-offs have been reported for nearly a century, with limited success in mitigation. In 2016-2017, a major mortality event revealed yessotoxin, produced by harmful algae, at levels of 2.20 mg/kg in shellfish—enough to cause die-offs. From 2021-2023, researchers found yessotoxin levels ranging from undetectable to 2.36 mg/kg, with all South Salish Sea samples containing quantifiable levels. This highlights a stronger link between yessotoxin exposure and shellfish die-offs than previously recognized. As climate change, urban runoff, and drought increase biotoxin risks, these findings emphasize the urgent need to protect food security and sovereignty for communities relying on shellfish as a dietary staple.
The Environmental Speaker Series is free and open to the public. Talks are held each Thursday at 4:30pm in Academic Instructional Center West, room 204. Join us at WWU or online on Zoom!
