DFG News Release

Department of Fish and Game calls first invasive mussel checkpoint a success

The Department of Fish and Game (DFG) successfully completed an invasive mollusk inspection checkpoint May 22-23 in an ongoing battle against Quagga and Zebra mussels. The checkpoint, held along Interstate 5 in Cottonwood just before the Memorial Day weekend, saw 347 boaters come through—and no mussels.

“As a pilot effort, our checkpoint was a success,” said DFG Capt. Sherry Howell. “We made contact with each boater, provided them information, and moved them through the process quickly.”

Vehicles trailering watercraft north on I-5 near Redding were stopped for the mandatory inspections at a California Highway Patrol Inspection Facility. There were 24 DFG law enforcement personnel and three biologists working the inspection station each day. Three department interceptor vehicles were also available in the event drivers passed the checkpoint point without stopping. Only eight drivers had to be intercepted and returned.

Game wardens conducted an initial interview to assess the risk of vessels carrying mussels and the possible need for a more thorough inspection. Boats that were clean, drained and dry moved through the checkpoint quickly—an average stop time of just over three minutes. Boats determined to be at “high risk” for contamination were sent through a second inspection. Of the 347 vessels that were inspected, 44 were directed to the second inspection where K-9 units sniffed the boats for traces of Quagga and Zebra mussels. Ultimately, no mussels were found.

“Our K-9s are extremely useful in our effort to halt the spread of these mussels,” said Lynette Shimek, K-9 Program Coordinator. “The dogs quickly alert us to problems on vessels and focus our inspection efforts. They have also helped uncover evidence in poaching cases in other areas around the state.”

Many of the boaters that passed through the checkpoint understood the threat the mussels pose. However, DFG reinforced this understanding by distributing information about how to properly clean, drain and dry boats to help prevent the prolific mussels from further spread.

“This checkpoint gave us the opportunity to check our resources and to evaluate our education and inspection program,” said Howell. “Because boats are the primary transporters of these mussels, the department will be looking at future opportunities to conduct similar inspections in other locations.”

Quagga mussels were detected in the Colorado River system in January 2007 and were later found in San Diego and Riverside counties by state and local water agencies. Zebra mussels were discovered in San Justo Reservoir in San Benito County in January 2008.

Both species of non-native aquatic mollusks wreak havoc on the environment by disrupting the natural food chain and releasing toxins that affect other aquatic species. Although they range in size from microscopic to the size of a fingernail, they are prolific and attach themselves to hard and soft surfaces.

Zebra mussels inhabit water depths from four to 180 feet, while Quagga can reach depths more than 400 feet. Both mollusks can attach to and damage boat trailers, cooling systems, boat hulls and steering equipment. Mussels attached to watercraft or trailers can be transported and spread to other water bodies. Water in boat engines, bilges, live wells and buckets can carry mussel larvae (called veligers) to other water bodies as well.

A public toll-free number, 1-866-440-9530, has been established for boaters and anyone involved with activities on lakes and rivers seeking information on the invasive and destructive mussels.

For more information on the Quagga mussel, please visit the DFG Web site at www.dfg.ca.gov/invasives/quaggamussel.