TWIN FALLS, Idaho — Idaho state agriculture officials are using a new chemical treatment this September in their fourth year of efforts to eradicate invasive quagga mussels from the Snake River near Twin Falls.
RELATED | Fourth annual quagga mussel treatment underway on Snake River near Twin Falls
The Idaho State Department of Agriculture is targeting two hot spots along the Snake River above Twin Falls Dam, injecting copper molluscicide from six floating barges to depths of 15 to 30 feet deep. The treatment is targeting where quagga mussel colonies have been found among the rocky fissures and crevices of sub-surface canyon walls.
WATCH: Idaho tries new treatment to fight quagga mussels
Jeremy Varley is ISDA's Chief Treatment Engineer. Varley described where the mussels tend to settle.
"They like to be a little bit more protected, so we've been seeing them on the underside of those cracks that are usually opposite of the water," Varley said. "We also see them up under on clean surfaces."
This year's treatment introduces a new first-stage chemistry called EarthTec QZ, which will be pumped into the river for 72 hours. It will be followed by Natrix, the chelated copper product used in the previous three treatments. Officials are also deploying a granular product suspended in mesh bags near the colonies.
ALSO READ | Idaho continues its fight to eradicate invasive quagga mussels in the Snake River
ISDA Bureau Chief Nic Zurfluh said lessons from prior years are shaping this year's more targeted approach.
"We're utilizing different chemistries, different molluscicides at different times, all that are designed to get the product at the depth profile where we're finding quagga mussels," Zurfluh detailed.
Zurfluh said the focus this year is on a specific depth band and the crevices where mussels have been hiding.
"We're addressing a specific depth band and fissures and hiding places that we've been finding quagga mussels, making sure that we get adequate level of copper molluscicide within those areas to cause mortality of the quagga mussel."
Each year the copper treatments have been performed, some fish in the Snake River have died as a result. Zurfluh said that is a trade-off officials are willing to accept, because allowing the mussels to spread downstream would cause far greater damage.
"If we allow mussels to extend down the Snake River into the lower Snake or the Columbia, you're gonna see a massive impact of salmon and steelhead that would be much more profound than the impact that we've had to the fisheries here, including the Sturgeon and Centennial Park," Zurfluh explained.
Surveys performed by scuba divers this week have already located several dead adult mussels, something officials see as a good sign the treatment is working.
This story was initially reported by a journalist and has been, in part, converted to this platform with the assistance of AI. Our editorial team verifies all reporting on all platforms for fairness and accuracy.
