Flexing muscles over mussels

By BRIAN WALKER

Staff Writer

Barely a month into Idaho's watercraft inspection season, mussel-fouled vessels are already being intercepted.

Nic Zurfluh, invasive species manager for the Idaho State Department of Agriculture, said that as of Monday, 14 such watercraft have been found at inspection stations statewide, including three at the station on westbound Interstate 90 near Fourth of July Pass. That one led the state in nabs last year.

"The spread of aquatic invasive species like mussels would threaten the Idaho we know and love," Zurfluh said.

All of the mussels found so far have been dead. More than 7,000 watercraft statewide have been inspected already this year.

Invasive mussels are easily transported, and once attached to an area can quickly take over and are hard to eradicate. Colonies clog pipes in water systems, threatening hydropower and irrigation, as well as municipal water supplies. When they take over a lake, it can quickly lose its recreational value.

"If quagga or zebra mussels were to infest Idaho’s waters, as they have done in other states, it could cost the state nearly $100 million annually in damage and lost revenue," Zurfluh said.

Invasive mussels are thought to have been carried over by transoceanic shipping containers through ballast water in the late 1980s. They started in the Great Lakes, and since then, they’ve been transported down the Mississippi Basin and to the west.

After the invasive mussels were found in Arizona’s Lake Mead in 2007, Idaho began monitoring lakes and rivers in 2009.

"Now we’re seeing more overland transportation," Zurfluh said.

More than 600,000 inspections have been performed in Idaho since the program began and 258 mussel-fouled watercraft have been intercepted.

Last year, of the 110,468 watercraft inspected, 50 were mussel-fouled. The westbound I-90 station led the state in interceptions with 13.

Other local inspection stations include Highway 53 near the state line, eastbound Interstate 90 at the Huetter rest area, and on Highway 3 near Rose Lake.

Owners of motorized and non-motorized watercraft must stop at inspection stations.

ISDA and cooperating partners monitor more than 80 water bodies statewide for the presence of mussels. Monitoring includes multiple sampling events at each waterbody for all life stages of the mussels. To date, there have been no detections of invasive mussels in Idaho or the Columbia River Basin.

Zurfluh said studies have shown that Idaho water is suitable for mussel habitat.

"We assume Idaho and the Columbia River Basin are at risk for infestation, and our program is actively working to prevent that from happening," he said.

Boat owners are encouraged to do their part to protect Idaho's water by following the "clean, drain and dry" recommendation involving their watercraft after each use.

For more information on watercraft inspections, visit: www.invasivespecies.idaho.gov