Quagga treatment underway in the Snake River, fish mortality expected in treatment areas

TWIN FALLS, Idaho (KMVT/KSVT) — After tagging fish in Snake River over the last few days, the next phase of the IDSA’s treatment for the quagga mussel infestation began on Tuesday, October 3rd. The treatment plan will occur in two phases over the course of a 10-day time span.

The treatment plan involves putting chelated copper into the river, which is likely to cause fish mortality.

Fish and Games will be present at the river to collect the dead fish during the 96 hour window. This will allow them to estimate the population of the remaining fish in the river.

“It is unclear what that level of mortality is going to be and that’s why we were out there ahead of time marking fish for that part of the evaluation,” says Regional Fisheries Manager Mike Peterson. “In terms of sturgeon, there are some sturgeons within treatment reach, we do expect mortality.”

According to ISDA’s director Chanel Tewalt, the level of copper that is being put into the water is below the human health standard and will not affect the surrounding wildlife.

“We expect it to be a mortality that will occur directly in the treatment area, but this type of product passes over the gills more than it settles into the meat,” says Tewalt. “So we don’t have concern for wildlife that would consume fish down river and we don’t have down river advisories either.”

After the 96 hours of phase one is complete, ISDA will implement phase two which will last until October 13th.

There is still a “no fishing” and “no hunting” order in effect, along with a closure to Snake River.

The ISDA along with Fish and Game and the Twin Falls County urge the public to stay away from the water in the affected areas until further notice.

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