In September, quagga mussels were detected in the Snake River near Twin Falls, Idaho. These invasive mussels form hard, sharp clusters that clog hydropower, water conveyances, hatcheries, fish ladders, and other infrastructure. Surveys found an adult mussel and multiple plumes of free-floating larvae, which can survive for a month before settling. While Idaho chemically treated sixteen river miles in October to try and eliminate this harmful aquatic invasive species, the larvae may have floated into Washington before treatment.
This first quagga mussel detection in the Columbia River basin is about 375 river miles from Washington. While the Washington Department of Fish and Wildlife conducted extensive monitoring and watercraft inspections, greater readiness and response capacity will be needed if the mussels are detected in Washington.
While there it is unclear if the Idaho treatment was done in time, there is no uncertainty about the risks to Washington. The known annual cost of keeping Washington’s hydroelectric dams functioning is more than $100 million annually. A quagga mussel infestation may harm habitat restoration efforts, fish passage, commercial and recreational fisheries, tribal cultural resources and treaty rights, the already threatened and endangered salmon and steelhead populations, recreational access, water supplies for agriculture, and Columbia River shipping. Join Washington Department of Fish and Wildlife staff to learn more about the threat these mussels pose to the economy and environment, how to identify and report this devastating pest, and the department’s efforts to monitor for invasive mussels, improve protections for the Snake and Columbia Rivers and infrastructure, and reduce economic and environmental impacts. One pesticide recertification credit from the Washington Department of Agriculture has been requested.
This event will be held via Zoom.