The Zebra Mussel

The zebra mussel (Dreissena polymorpha) is a small bivalve mollusk native to Europe. The mussel was first observed in North American lakes only recently. Initial colonization may have occurred in 1986, probably from larvae discharged in ballast water. The zebra mussel is a potentially serious pest. In high densities, it presents major problems for both human-made structures and for the ecology of infested bodies of water. One of the most harmful impacts is the colonization of intake cribs and pipes serving water treatment plants, power generating stations, and industries. Attracted to swift-moving water carrying large amounts of nutrients, mussels quickly colonize and block these intake pipes. As an efficient feeder, the zebra mussel is capable of removing large amounts of seston from the water. A benthic (bottom dwelling) organism, the zebra mussel effectively removes nutrients from the water column and deposits them on the bottom of the lake, river, or estuary in which it lives. In addition to diverting primary productivity from the plankton to the benthos, zebra mussels may also cover substrates used by other organisms and foul sedentary benthic organisms.