Quagga mussels, an exotic species native to Ukraine that was first found in the Great Lakes 18 years ago, have been found in a fifth San Diego County reservoir.Quaggas apparently were transported from Europe to Lake Erie in the United States in the ballast water of oceangoing ships, The San Diego Union-Tribune reported.
The mussels grow virtually unmolested because they have no natural predators. They clog pipes and screens at power stations, water treatment plants and agricultural irrigation lines.
Photo: New York Sea Grant
