|FOR IMMEDIATE RELEASE
November 12, 1997
|Linda Drees 913-539-3474 ext. 20
Diana M. Hawkins 404-679-7289
What's round, black and tan striped, less than an inch long and can cost water use
facilities over $200,000 annually? The zebra mussel.
The seriousness of potential zebra mussel infestation is so great, in fact, that a
consortium of state and federal agencies will hold a three-day conference November 18-20,
1997, in Kansas City, Missouri to weigh the risks zebra mussels might pose to water
supplies and biological communities in the West.
"We hope this conference will help focus public attention and help prevent a very
serious problem," according to Linda Drees, a conference coordinator and aquatic
nuisance specialist with the U.S. Fish and Wildlife Service, one of the six sponsoring
agencies. "We don't have zebra mussels in this region, yet," Drees noted,
"but almost all the biological requirements for them would be easily met in most of
the major river systems and impoundments."
The zebra mussel is a small shellfish native to the Baltic Sea drainage in northern
Europe. It is believed that they were first inadvertently introduced into North America
through the release of ballast waters from cargo vessels. Ships often take on ballast
water in their home ports and later discharge it to help maintain buoyancy and load
balance. The zebra mussel was first discovered in Lake St. Clair in 1988. Since that
initial discovery, the mussel has spread virtually throughout the Great Lakes Region,
inflicting tens of millions of dollars in damages to municipal and industrial water intake
The mollusc feeds by filtering near-microscopic food organisms, called plankton, from
the water. They try to locate in favorable current areas that will bring the maximum
amount of food past; hence, structures that create or enhance current such as water
intakes, piers and bridge pilings are extensively colonized. Concentrations of up to
700,000 per square meter have been observed in the Great Lakes.
Biologists are still evaluating the impacts of zebra mussel invasions in the Great
Lakes and adjacent drainage, but the preliminary reports are cause for concern. Field
studies have indicated that zebra mussels can cover and displace native freshwater clams
and mussels, many species of which are already threatened or endangered and facing grave
threats from environmental contaminants. It is also believed that some popular species of
gamefish such as bass and walleye may be negatively impacted either by zebra mussel
infestation of their spawning sites, or by filtering out many of the small plankton that
the fry of these fish require for their early growth.
"We want people to know the threat is real and fortunately, there are some
positive steps that can help reduce the chance for infestation," said Drees. Boaters,
for example, should be extra sure to thoroughly drain their live wells and carefully check
the hull and motor housing on their boats before departing a lake or river -- especially
if they've been boating anywhere in the upper Mississippi River or Great Lakes area."
The three-day conference is sponsored by the U.S. Bureau of Reclamation; U.S. Army
Corps of Engineers; Kansas City, Missouri Water Services Department; Sea
Grant/CSREES-USDA; the Zebra Mussel Training Initiative; and the Service. The conference
will be held at the Wyndham Garden Hotel in Kansas City, Missouri, and will feature
sessions on zebra mussel biology and risk manage-ment, monitoring, impacts and control
methods. Registration fee prior to November 18, 1997 is $50.00; after that date $60.00.
Additional conference information is available from Linda Drees, U.S. Fish and Wildlife
Service (913-539-3474 ext. 20), or Tracie Green, U.S. Bureau of Reclamation (303-236-6007,
1997 News Releases