Lake County started its mussel prevention program in 2008 and at that time just about everyone predicted quagga mussels would be in Clear Lake within a few years. The good news is the program has been highly successful and to date there has not been a single quagga mussel found within the county’s lakes and waters.
Actually, Lake County is far ahead of its neighboring counties in the mussel prevention program. No other county in Northern California has a prevention program as good as Lake County.
Quagga mussels are not a native species to California or even the United States. The mussels are native to the Dneiper River of the Ukraine, which is near Russia. The quagga mussel got its name after an extinct species of an African zebra. It has an average life span of three to five years and is a filter feeder. It pulls water into its shell cavity where plankton is removed. Each adult mussel is capable of filtering one or more quarts of water a day.
The quagga mussel is a prolific breeder and each female is capable of producing up to a million eggs per year. The larva are called veligers. In their native land they have natural predators, including ducks and various species of fish. In America there are no predators although scientists have recently discovered that yellow perch and redear sunfish eat them.
The mussel was first discovered in the United States in Lake Erie back in 1989. It is believed the mussels got into Lake Erie in the ballast tanks of an ore ship from Europe that arrived to haul iron ore to Europe. The ships fill their ballast tanks with water when the ship is empty to stabilize it. By law all ships are required to empty their ballast tanks 2 miles out to sea before entering U.S. waters. Apparently one ship failed to do so and when it emptied its tanks in Lake Erie the water contained quagga mussels. By 2007, quagga mussels were discovered in Lake Mead in Nevada. The mussels then spread to other lakes in Nevada, Colorado, Arizona and Southern California. Scientists say the mussels were more than likely spread to the other lakes by boaters.
Once the mussels get established in a lake there is no way to eradicate them. In fact, not a single large body of water that has been contaminated with mussels has had the mussels successfully eradicated.
It is surprising that Clear Lake remains free of the mussel. The mussel prefers water that contains calcium and other elements, all which can be found in Clear Lake. One of the methods the county uses to check for the presence of mussels is to install blocks of concrete that have calcium. The free floating veligers will attach themselves to the blocks. The blocks are checked monthly. To date, no veligers have been found on the blocks.
Officials are concerned that boats from out of the area will carry the veligers to the lake and that is the reason the county requires that all boats from out of the county be issued a new quagga mussel sticker monthly. Residents of the county are required to get a sticker annually. Before a sticker is issued, the boater must fill out a form stating where the boat was last put into the water. If the boat is coming from an infected water it must first be decontaminated by county personnel. If a boater is stopped on the water by a member of the sheriff’s boat patrol and the boat doesn’t have a current sticker, the operator can be issued a ticket and fined. The county also has monitors at public ramps to ensure that all boats display a valid sticker before they can launch.
When the sticker program first started in 2008 a number of boaters disagreed and even protested having to pay the $10 sticker fee. The good news is that most of these boaters have now come to expect that they are required to have a current sticker and endorse the program. No one wants Clear Lake to be infected with quagga mussels. Clear Lake is one of the oldest lakes in the world and we want to protect it from invasive species of mussels and plants.
