Zebra Mussels

Baltimore officials aren't taking any chances on keeping a thumbnail-sized mollusk at bay.Worried by the spread of zebra mussels, the fast-breeding bivalves that have infested the Great Lakes, the city is preparing to spend from $2 million to $6 million to protect its public water supply.The Board of Estimates approved hiring a consulting firm yesterday to complete plans to prevent the black-and-white striped mollusk from clogging water intakes at three reservoirs and 67 miles of water tunnels leading to filtration plants.

While most of the Chesapeake Bay may be safe from the fast-breeding zebra mussels that are creating havoc in the Great Lakes, Baltimore's watershed officials will spend $6 million to defend inland streams and reservoirs from the invaders.The fingernail-sized bivalves from Eastern Europe have clogged waterworks and attached themselves to boats and piers wherever they have appeared, disrupting water supplies and causing millions of dollars in damage."I believe we will be seeing zebra mussels in fresh waters in Maryland . . . in this decade," said Dr. Vic Kennedy of the University of Maryland Center for Environmental and Estuarine Studies.

Satisfied that the spread of zebra mussels can be controlled through less-restrictive measures, Mayor Kurt L. Schmoke said yesterday that the city will lift the boating moratorium on three city reservoirs in March.The moratorium was imposed last April to protect the city water supply from zebra mussel infestation. Zebra mussels are small organisms that multiply quickly and can clog pipes and cause millions of dollars worth of damage.The moratorium angered recreational boaters and sportsmen who enjoyed angling for bass, rockfish, perch and catfish on the three city reservoirs: Liberty, Loch Raven and Pretty Boy. But city officials considered the precaution necessary to avert the spread of zebra mussels, which can cling to boat bottoms.

In the current issue of Ducks Unlimited Canada Conservator is an article about the zebra mussel, the tiny striped clam whose presence within a few hundred miles of Prettyboy, Liberty and Loch Raven caused the Baltimore Department of Public Works to restrict fishing boats on the city's reservoirs.City officials feared that anglers would bring the mussel into the reservoirs where it could block water piping systems as it has in the Great Lakes.Officials thought that the clam has no natural predators in this hemisphere.

Five Maryland fishermen and two businessmen met with Baltimore's director of public works yesterday to discuss the closure of two city-operated reservoirs to boats and to offer their assistance with a potential zebra mussel problem.Baltimore's Prettyboy and Liberty reservoirs have been closed to boaters and anglers in boats since March 1, when the Department of Public Works decided to postpone issuing mandatory permits until it could find a way to delay or prevent zebra mussel infestation.

Fishermen who on Tuesday and yesterday applied for permits to use their boats on Prettyboy and Liberty reservoirs this season will not be issued permits until a potential problem with zebra mussels is investigated, an official of the Baltimore City Department of Public Works said yesterday."

Zebra mussel. Probably by now you have heard the words and -- unless you are a boat fisherman who uses Liberty, Prettyboy or Loch Raven reservoirs and who was hit with a one-year suspension of privileges Friday by the Baltimore Department of Public Works -- you might well have heard those words too often.Enough with the zebra mussels already, you say. You don't fish reservoirs. You don't fish fresh water. You don't fish anywhere the current is slower than you can walk.OK, we won't use those words.

Fishermen who on Tuesday and yesterday applied for permits to use their boats on Prettyboy and Liberty reservoirs this season will not be issued permits until a potential problem with zebra mussels is investigated, an official of the Baltimore City Department of Public Works said yesterday."

Six or seven years ago, a transoceanic ship discharged freshwater ballast into one of the Great Lakes to start a series of events that have struck home in Carroll County.That is how fisheries scientistsin Ohio figure the zebra mussel hitchhiked to North America from Europe. Quickly, Lake St. Clair was infested, then Lake Erie, followed by others in the Great Lakes chain and, eventually, spreading into NewYork and the St. Lawrence River.Infestations were detected last year in the upper Susquehanna River.

There's a remote possibility the Chesapeake Bay could soon be transformed into the cleanest estuary in the world. Rivers now turbid and dingy and laden with silt and nutrients may become crystal-clear tributaries free of municipal waste and industrial pollutants.Local and federal agencies have spent nearly $1 billion to achieve this goal, but the actual cleanup of the Chesapeake may eventually be credited to millions of tiny bivalves known as "zebra mussels."Unfortunately, these highly prolific, efficient filter feeders could also bring about the demise of the world's largest estuary.

Alarm bells have been sounded before about invasive species that might devastate the Chesapeake Bay - the northern snakehead, the scary, land-crossing "Frankenfish" that's now a naturalized resident of the Potomac River comes most immediately to mind. But few have gotten the advance billing for pure destructiveness that the zebra mussel has received. Last fall, six dead zebra mussels were found in the lower Susquehanna River, two of them in Maryland waters - including one at the Conowingo Dam. If history follows its usual course, it's not a matter of "if" but only a question of "when" the freshwater mussels become established in the less saline portions of the Chesapeake Bay. What might result from this?

More zebra mussels have been found in the Maryland portion of the Susquehanna River, state environmental officials confirmed yesterday. The alien mussels, which can cause millions of dollars in damage to water supply and hydroelectric intake pipes and upset the local ecology, were attached to a boat at Glen Cove Marina in Harford County. Earlier this month, a single mussel was found within the intake hydroelectric station at Conowingo Dam, the first sighting in the state. More mussels have been found six miles upstream in Pennsylvania at Muddy Run Reservoir.

For the first time, Maryland waters have been invaded by an alien mussel capable of fouling public water systems, destroying native aquatic life and causing millions of dollars in damage. A single zebra mussel was scooped from inside a water intake pipe upstream from the Conowingo Dam that spans Harford and Cecil counties by a fish survey team on the Susquehanna River. The mussel, about a half-inch in size, was sent to a Pennsylvania laboratory for positive identification. "Finding just one doesn't make sense," said Jonathan McKnight, an invasive species expert with the Maryland Department of Natural Resources.

One of the toughest things I have to do as a Baltimore biology teacher is to teach my students about the scientific method. That is, basically, the set of rules under which science operates. Every year, when my kids take the High School Assessment, they have a lot of difficulty on that section of the test. They don't quite understand about variables and how to run a controlled study. I always worried that this would hinder them if they went into a scientific profession. Now, however, I can take comfort in the fact that it prepares them for jobs with the Maryland State Department of Education.

With all the jokes about northern snakeheads, it's easy to forget that there are nasty critters and plant life out there just itching to move in like some freeloading relative. At first, they might appear to be welcomed guests with some redeeming qualities. The easy-on-the-eye, tough-on-plants mute swan comes to mind. But it doesn't take long before Swan Lake turns into the Black Lagoon, home of another web-footed creature. Which brings us to the next unwanted visitor lurking just over the horizon: the zebra mussel.

Tim Mullady peers into a microscope in a darkened room at the Smithsonian Environmental Research Center in Edgewater. He is counting cells from a sample of ballast water taken from a ship, looking for Vibrio cholerae, the bacteria that cause human cholera -- and sometimes is discharged from that ballast into local waters along with scores of other "foreign" organisms. Mullady is part of the Marine Invasion Research Laboratory, which provides information from the forefront of the research community to the Coast Guard and Congress.

Tim Mullady peers into a microscope in a darkened room at the Smithsonian Environmental Research Center in Edgewater. He is counting cells from a sample of ballast water taken from a ship, looking for vibrio cholerae, the bacterium that causes human cholera - and sometimes is discharged from that ballast into local waters along with scores of other "foreign" organisms. Mullady is part of the National Marine Invasion Research Program, which provides the Coast Guard and Congress with information from the forefront of the research community on this issue.

STILLWATER, Minn. - In the growing annals of invasive species, the fingernail-size zebra mussel hardly seems as fearsome as others that have recently made headlines - the bighead carp that have been leaping onto fishing boats in the Mississippi River, the "Frankenfish" snakehead that ate a Maryland pond. But what the zebra mussel lacks in style, it makes up for in destructive ability: Tiny but prolific, they can quickly take over a body of water, clogging power plant intake pipes, stealing food and oxygen from other species and even suffocating the native mussels that they attach themselves to and eventually encrust.

Zebra mussels, one of the most notorious aquatic pests in the nation, have been discovered in a small New York reservoir that feeds into the Susquehanna River, and top scientists are meeting today to outline a plan to prevent them from spreading in the Chesapeake Bay watershed. The tiny mollusks, which are native to Europe and have no natural enemies here, have spread rapidly since they were brought to the Great Lakes in a ship's ballast water in the early 1980s. They grow so quickly that they can clog intake pipes at power plants, factories and municipal water plants, forcing them to shut down.

LAKE GEORGE, N.Y. -- A year and a half ago, it looked as if Lake George, a blue jewel in the green Adirondacks, had dodged a biological bullet -- the zebra mussel, an invasive European mollusk that is clogging pipes, crowding local aquatic life and turning beaches into toe-slicing shell heaps from Michigan to the Hudson River. Scientists had found microscopic mussel larvae in the water, probably imported in the bilges of boats. But lab tests showed that some quirk of Lake George chemistry -- probably a lack of calcium -- seemed to keep them from maturing and reproducing.