The mollusks have invaded water basins around the US, but not yet gained a foothold in the Columbia River Basin
Update, Sept. 25, 2024: On Sept. 24, 2024, the Idaho State Department of Agriculture announced that a small number of quagga mussels were detected in a treated portion of the Snake River. “One of our greatest success stories as a state has been the coordinated, rapid response to quagga mussels last fall, but we knew we would be on watch for a period of five years,” said Idaho Gov. Brad Little in a statement following the announcement. “I have great confidence in the team at the Idaho State Department of Agriculture and their many, many partners to continue to tackle this problem with minimal disruption to the public.” —Editor
By Kendra Chamberlain. August 21, 2024. It’s been nearly a year since the dreaded quagga mussel was first detected in Idaho’s Snake River near Shoshone Falls.
The discovery swung the Idaho State Department of Agriculture (ISDA) into a frenzy to eradicate the tiny creatures from its waters.
The state spent some $3 million last year to dump a copper-based treatment into the river in three sections, killing virtually everything in its path—aquatic life, plants and fish alike.
But the treatment plan—considered one of the most aggressive ever undertaken in the United States—seems to have worked.
So far, no new quagga mussels have been detected, as reported by the Idaho Statesman.
The tiny quagga mussels are a danger to the Columbia River Basin. The mollusks are aggressively invasive, coating every surface they come in contact with and wreaking environmental and economic havoc.
The mussels have invaded important water basins around the United States, but so far haven’t gained a foothold in the Columbia River Basin.
Quagga mussels outcompete native freshwater mussels for food, and even attach to native mussel shells, killing them.
In September 2023, ISDA detected a plume of mussel larvae, called “veligers,” as part of routine monitoring of state waterways.
After more investigation, a diver working for the department was able to locate a single adult mussel, smaller than a fingernail, located about 16 feet underwater.
Female quagga mussels can release up to 500,000 eggs per year, which float freely and can easily spread throughout waterways.
ISDA previously told Columbia Insight the department doesn’t know how the species reached the Snake River, or how long the species was present in the river before detection.
The Idaho Statesman reports the department will continue intensive monitoring for the mussel for possibly five years before Snake River can be considered free of the invaders.
Of course, the mussels may be inadvertently introduced at any time, which is why ISDA is pleading with the public to stay vigilant about cleaning watercraft and stopping at mandated watercraft inspection stations.