UpDate - Vol. 13, No. 39, Page 2
August 4, 1994
Zebra mussel threat invading from the north

      "In July 1988, the zebra mussel (Dreissena polymorpha--a
   creature new to North American waters--was sighted in Lake St.
   Clair, near Detroit, Mich. A native of the Black Sea, the small
   black-and-white striped mussel apparently hitched a ride to the
   United States in the ballast water of Eurasian tankers bound for
   the Great Lakes.
      Soon after it arrived in the Great Lakes, the zebra mussel
   began wreaking havoc, for the tiny mollusk (average size: 1-1/2
   inches) can attach itself firmly to virtually any solid object in
   fresh or slightly brackish water, with often disastrous results.
      "In the Great Lakes region, the zebra mussel has clogged the
   intake pipes of municipal water plants and power companies and
   even the water systems of golf courses. It has glued itself to the
   shells of other freshwater mollusks, including several species of
   endangered clams, effectively smothering them. . . . "

                    from"Zebra Mussel: Present Threat, Future Danger?"
                                                   --A report from the
                             Mid-Atlantic Sea Grant Network, 1992-1993

     This excerpt from a 10-page report gives a good idea of the
threat of the zebra mussel. The concern about its dangerous potential
is why the National Sea Grant College Program has initiated a major
research effort to determine better ways to control the zebra mussel.
Because it poses a real threat to the Mid-Atlantic region, the
University of Delaware Sea Grant College Program has been working in
association with other Sea Grant programs in the region to inform a
diverse public--including industry, resource managers, legislators and
water users--about the zebra mussel and its potential impacts.
     Additional information indicates that the large numbers of the
invading organism, and its method of feeding, have caused a reduction
in the food supply needed by other shellfish and by the larval stages
of some shellfish.
     In addition, the zebra mussel's impact on fishing, boating and
beach use are significant. Costs associated with zebra mussel control
in the Great Lakes are estimated to approach $5 billion by the end of
the decade.
     Unfortunately, the problem is not confined to the Great Lakes
area.  The zebra mussel has expanded its range and has spread to the
Hudson, Mohawk, Illinois, Ohio, Mississippi, Ohio, Tennessee and upper
Susquehanna rivers. The organism is expected to infest a significant
portion of North American waters.
     One important result of the cooperative research and public
outreach effort has been the production of the zebra mussel report,
which contains background on the organism, an assessment of its threat
to the Mid-Atlantic region, research being conducted, examples of the
mussel's effects and a list of available publications and contacts
from New Jersey to North Carolina.
     Members of the University's College of Marine Studies Marine
Communication Office are involved in local public outreach efforts. A
variety of information is available, including decals to inform and
educate recreational boaters, a library on zebra mussel literature, a
slide presentation and videos.
     For additional information or copies of the Mid Atlantic Sea
Grant Network report on the problem, contact James M. Falk at 645-4235
or Tracey Bryant at 831-8185.