TWIN FALLS, Idaho — The Idaho State Department of Agriculture (ISDA) says it is wasting no time in developing a treatment plan to eradicate invasive quagga mussels detected on the Snake River near Twin Falls, using lessons from last year.
- On Monday, Sept. 22, ISDA announced the detection of larval veligers from quagga mussels, which is usually an indication that adult mussels are present and breeding.
- In 2023 the Snake River was treated with a copper chelate, eliminating aquatic life from the river.
- As with weeding a garden, ISDA's Invasive Species Bureau Chief said it's not common to remove all the targeted species on the first try.
- To see water bodies across Idaho that are being monitored for invasive species, ISDA has an interactive map on its website.
(Below is the transcript from the broadcast story)
"We're ready to go quite quickly, so we have a target of early October," Idaho said Director Chanel Tewalt, with the State Department of Agriculture.
After treating the Snake River to eradicate invasive quagga mussels last October, Tewalt says they're ready to do it again. "Every aspect of the treatment, which was already really successful, is going to be flavored with the lessons learned from last year," Tewalt said.
Regular sampling has found evidence of quagga mussel larval veligers in the mid-Snake River near Twin Falls. Now, ISDA is finalizing a treatment plan.
"As folks contemplate what it means this year, we were talking about a very small population last year and we had a treatment that definitely knocked back that population so we're still still talking about even lower numbers," Tewalt said. "But any numbers are not acceptable and that's why we're moving forward with another treatment."
"Quagga muscles are microscopic invisible to the human eye, so you're not able to see them see them," Nic Zurfluh said while on a boat in the Snake River. Zurfluh told me how they use delimiting surveys to narrow down what areas to focus their treatment.
"So consider this glorified coffee filter," Zurfluh said, holding up a plankton net with a 64 micron screen.
As Bureau Chief of invasive species, Zurfluh is highly involved with ISDA's survey of Idaho waterways, looking for a needle in a haystack.
Thousands of times this summer not just on the snake, but on water bodies all across Idaho.
"We took our number of statewide samples last year and we have doubled it," Tewalt said. "That was our goal, knowing that we had an issue here on the mid snake, we knew that statewide we had to do so much more when it came to surveillance."
The murky zooplankton in the bottles is scanned both by microscope, and molecular genetic testing to determine if it is in fact quagga mussels.
Zurfluh says it is rare in invasive species to fully eradicate anything on the first try.
"Even like weed control in your garden: very rarely do you get all of them your first time," Zurfluh said. "You need to be diligent and actually now we need to be doubling down finding the extent to the infestation and getting a treatment plan developed to address that. It's rarely a one-and-done."
The upcoming treatment should look similar in many ways to the treatment last year, with roughly two weeks of river closures, followed by limited closures in focus areas.
