State plans weekend enforcement to stop invasive mussels Written by Elizabeth Larson Thursday, 28 August 2008

State officials say they're planning to keep a close eye on the thousands of boats entering California this Labor Day weekend in an effort to thwart the introduction of invasive zebra and quagga mussels to any new bodies of water.

The California Department of Food and Agriculture's (CDFA) border stations will inspect watercraft at six border stations along the Nevada and Arizona borders: Truckee, Needles, Winterhaven, Blythe, Yermo and Vidal.

“This is a good beginning to a more complete program of boat inspections within the state,” said Sen. Pat Wiggins, who chairs the Joint Legislative Committee on Fisheries and Aquaculture, which deals with invasive species as well as other issues. “Until every boater knows the serious, potential threat of quagga mussels invading our precious lakes, waterways and pipelines, inspections are a necessary inconvenience.”

Funding for the inspections was granted to CDFA after quagga mussels were discovered in the Colorado River last year, the agency reported.

Since early 2007, CDFA has intercepted 200 mussel-infested watercraft from among the 150,000 watercraft it has inspected. In addition, 14,000 watercraft were cleaned and/or drained of all water that could harbor the mussels.

This weekend an estimated 4,000 watercraft will enter California, some of which CDFA estimates will have quaggas and zebras along as hitchhikers.

The mussels have infested several Southern California lakes and waterways, but so far have not been found in Northern California or in Clear Lake, as Lake County News has reported.

The quaggas are particularly invasive in lakes with low acidity, such as Clear Lake, Wiggins noted.

“Entry of even a few quaggas into Clear Lake, the largest body of water in the Coast Range, could permanently upset the lake’s benefits that so many people enjoy,” Wiggins added.

The mussels attach themselves to boat hulls or may be free-swimming larvae in trapped water in boat bilges, live wells, and other places capable of harboring water while boats are in transit, CDFA reported.

CDFA reported that when its inspectors find the exotic mussels on watercraft, the vessels are cleaned and the owners issued a quarantine notice prohibiting the craft from entering California waters until a final inspection is conducted by the California Department of Fish and Game.

The dangerous pests can alter habitat and water chemistry, making waterways uninhabitable to native species, officials reported.

They've caused serious environmental and economic impacts for infested areas such as the Great Lakes. In a July Chicago Tribune report, it was noted that the quagga mussel – which invaded Lake Michigan 20 years ago – has had a population explosion in recent years and now is popping up across the lake's floor. That is part of an ecological domino effect that is rapidly changing the lake's ecosystem.

In an effort to protect the county's water bodies from the mussels, earlier this year the Board of Supervisors adopted and ordinance that made Lake County's one of the first governments in the state to set up an invasive species inspection program.

All boats entering the county's lakes must have an inspection sticker after completing a screening and, if necessary, a full inspection to certify they are mussel-free, as Lake County News has reported. Any vessels that don't pass inspection will not be allowed to launch until after they've been decontaminated and reinspected.

The quagga and zebra mussels are believed to have traveled from their native Ukraine to the United States through means such as the ballast water in oceangoing ships.

Earlier this month, the Associated Press reported that a bill to set federal cleanup standards for such ships is deadlocked in Congress, because Sens. Barbara Boxer (D-California) and Daniel Inouye (D-Hawaii).

Part of the disagreement centers on Boxer's concern that the federal law could preempt California's stronger standards, according to the Associated Press. She also wants the Clean Water Act to be partially responsible for governing the program, while the Coast Guard would remain in charge of the program according to Inouye's legislation.

In order to keep quagga and zebra mussels from spreading to Clear Lake and other bodies of water where they've not been detected, state and local officials advise following these steps.

– Boaters should inspect all exposed surfaces, wash boat hulls thoroughly, remove all plants from boat and trailer, drain all water, including lower outboard units, clean and dry livewells and bait buckets and dispose of baitfish in the trash.

– Watercraft should be dried for at least five days between launches in different fresh bodies of water.

– Have boats and other watercraft inspected as part of the Lake County Invasive Species Inspection Program. For information or to find the nearest inspection location, visit the Lake County Mussel Web site at, or call the Lake County Mussel Hotline at 707-263-2556.

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