![]() They even hamper shipping by covering hulls and piers, sometimes even infiltrating boats to the extent that their engines explode. They disrupt farms, drinking water and electricity by plugging electric and hydro utilities’ pipes, screens and filters. introduction.ĭreissenid mussels like zebra mussels and quagga mussels blanket lake bottoms, wreaking havoc on aquatic ecosystems and recreational activities such as fishing. David Cowles, a biology professor at Walla Walla University, who has been keeping tabs on zebra mussels since their U.S. “There is no way to get rid of them without destroying native species as well, so when they invade an area, it is presumably a permanent change,” says Dr. Since they were first discovered in the Great Lakes in 1986, these rapid-spawning animals have infested every watershed in the Lower 48 except the Columbia River Basin. But they are disastrous almost everywhere else. Zebra mussels - fingernail-sized mollusks named for their striped shells - are benign in their native Black Sea and Caspian Sea ecosystems. Anderson, who runs Fish and Wildlife's 10-person Aquatic Invasive Species Unit, says his life has been “chaos” since then. (Live Zebra Mussels have been found attached to boats crossing from Nevada into California.“All of a sudden, my phone line started going off,” he said Thursday at noon. And if you have a boat, or know someone with a boat, see that the hull is completely cleaned off before moving it from one body of water to another, especially if you cross a divide between river drainage systems. What can you do? You can become informed (starting with ). Populations of native mussels inevitably decline once the Zebra Mussel is established. Up to 10,000 Zebra Mussels have been found attached to a single shell of a (large) native mussel. To be the tendency of the Zebra Mussel to attach to the shells of live native mussels, many of which are already threatened or endangered (due to water pollution). ![]() There was much initial concern that Zebra Mussels could clog water intakes along the lakeshore but apparently technological developments have kept pace with that. Most diving ducks love them (mussels, not cormorants). The clearer water must make it easier for fish-eating birds to see their prey and this may contribute to the cormorant population explosion around Lake Erie. The water is clearer, meaning sunlight can penetrate further and algae can grow at greater depths, replenishing oxygen critical to bottom feeding insects such as mayflies, which have returned to high numbers not seen since the 1950s. ![]() Thus for the last two decades gazillions of mussels have been busily filtering Lake Erie and this has definitely changed the ecosystem (which partly defines a true “invasive”). Zebra Mussels are filter feeders, straining microorganisms (mostly algae) from over a gallon of water per mussel per week. Zebra Mussels may live up to 5 years and a single female may lay several million eggs during that time. (I saw my first “wild” Ohio Zebra Mussel on a marker buoy at Huron in 1989.) Rocks and shells of native mussels are other favorite attachment sites but shipwrecks, concrete breakwalls and water intakes will also suffice. Zebra Mussel young (“larvae”) are free-floating before they settle down and start forming a shell. Much of this dispersal is due to the mussels’ attaching themselves to hard surfaces including the undersides of ships and boats. (Captains are supposed to see that ballast tanks are flushed with saltwater on the way over but apparently not everyone does this.) Within a few years the mussels had spread to at least 19 states and Ontario. Lawrence Seaway before emptying its ballast tanks somewhere near Detroit. Most likely they arrived in freshwater ballast evidently a freighter loaded fresh water in Europe and steamed over to Canada and up the St. Clair just upstream from our own Lake Erie. The first find in North America was in Lake St. The Zebra Mussel originally inhabited central and eastern Europe but by 100 years ago it had spread throughout the continent, abetted by the interlacing canal systems connecting river drainages.
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