Invasive mussels threaten Pacific Northwest

Quagga and zebra mussels are slowly making their way to Idaho and if introduced to the area they will cost the state millions of dollars and threaten Idaho’s tourism, hydroelectric and agricultural industries.

House and Senate committees held a joint meeting Feb. 22 to hear experts on invasive mussels.

“This is our 13^th year holding a workshop on invasive species and the spread of zebra and quagga mussels is a statewide concern,” said Nate Fisher, board president of the Idaho Council on Industry and Environment. “They have already been found in Lake Mead and Lake Powell below us and larva were just found in Montana last year.

“If they make it into Idaho they will spread through the entire Columbia River Basin,” he said. “Frankly, I think this is the biggest environmental issue facing the Pacific Northwest.”

Quagga mussels are native to Ukraine and zebra mussels are native to the Black Sea. They were introduced to the United States in 1989 in the Great Lakes, most likely by cargo ships. The mussels can create 1 million offspring a year and they threaten native species by feeding on nutrients from the water. An adult mussel can filter at least a liter of water per day – removing plankton, algae and various minerals, according to the Alberta Invasive Species Council.

The mussels reproduce rapidly and attach themselves to any hard surface available such as rocks, boats, dams, and agricultural pipes. The best protection against the mussels is prevention, because once they are introduced to a waterway they are virtually impossible to eradicate, according to the Alberta Invasive Species Council.

“These are savage creatures that know no boundaries,” said Jesse Taylor, of Bear Lake Watch, an environmental and commerce group formed to protect the tourist market of Bear Lake in eastern Idaho. Bear Lake Watch works closely with the Utah Legislature and groups that work to slow the spread of invasive mussels in the state.

If the mussels were to make it into Bear Lake, they would threaten four native species of fish and make the lake lose its clear, blue hue, Taylor said.

“The mussels need calcium to grow their shells, but the reason Bear Lake has its beautiful tropical color is because of the calcium deposit in the water,” Taylor said.

Along with hitching rides on boats, the mussels spread rapidly through flowing water. They would threaten most Idaho rivers and the hydroelectric dams that operate there.

“The costs would be highest in Washington and Idaho where we have a heavy hydroelectric economy,” said Matt Morrison, with Pacific Northwest Economic Region.

The joint committees discussed several ways to keep the mussels out, and will work on several bills to increase the number of boat inspection areas around Idaho, staff the areas 24 hours a day, raise money and create a new office to oversee invasive species policy.

Mussel larva were found in Montana in November at Canyon Ferry Reservoir and Tiber Reservoir. The Legislature plans to create three new boat inspection areas to closely monitor boats passing through the Idaho and Montana border.

There are 15 boat inspection areas now in Idaho.

“We are 50 miles away from having these things float into Idaho and then into the Columbia,” Morrison said. “Once they are in the Columbia their spread will be unstoppable.”

According to the United States Geological Survey, the only areas where zebra and quagga mussels haven’t been found in the continental United States are small pockets of states in the Northwest, Southeast and Northeast as well as Wyoming and New Mexico.