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Kraft, C., MAY 10, 1990. Zebra Mussel Update #01, University of Wisconsin-Madison, Wisconsin Sea Grant Institute -- A Newsletter produced by the Wisconsin Sea Grant Institute Zebra Mussel Update #01Editor's Note The invasion of the Great Lakes by the zebra mussel has the potential to be a greater disaster, in human terms, than the invasions of the parasitic sea lamprey, alewife and all the other exotic species in the lakes combined. This is the first in a series of Zebra Mussel Updates designed to provide timely information on the zebra mussel invasion, its spread and efforts to control it, and to enhance the sharing of such information among concerned individuals, agencies, industries and research institutions. ID: 19900510-1. Invader Profile Zebra mussels (Dreissena polymorpha) are marble-size, barnacle-like freshwater molluscs that colonize almost any underwater structure with a hard surface, including water intake pipes, boat hulls, harbor pilings, navigation buoys and commercial fishing gear. Colony densities range up to hundreds of thousands per square yard. Already infesting Lakes St. Clair, Erie and Ontario, zebra mussels are expected to spread throughout the other Great Lakes and eventually to inland lakes and waterways. Events in Lakes St. Clair and Erie indicate this organism has tremendous destructive potential. It is also clear that massive infestations can occur with little warning, since the zebra mussel was virtually unknown in the Great Lakes just two years ago. Lakeside power plants, industries and municipalities with water intakes in the nearshore region are likely to suffer the most serious and costly encrustations. One Great Lakes water utility has estimated that it may cost $50 million to $100 million a year to scrape the mussels from its intakes, and many Great Lakes water intake pipes will have to be redesigned to provide more access points for monitoring and removing the mussels. Possible controls include the use of intake screens, electrostatic filters, flushing with hot water and chlorination. In some cases it may be necessary to install secondary intake pipes so the primary pipes can be shut down for cleaning. The effects of zebra mussels on the ecosystem are unknown at this time. They are capable of colonizing spawning reefs and filter-feeding tremendous quantities of algae, which may adversely affect the reproduction success of certain fish. Some reports indicate they will also colonize submergent plants. On the other hand, diving ducks, lake sturgeon and certain other fish readily feed on the mollusc. Despite the "horror story" coverage zebra mussels have received lately in the news media, Europeans have coexisted with zebra mussels for nearly two centuries. But the immense expense, disruptions and inconveniences that they may cause here is a legitimate concern not only for the Great Lakes region, but for the nation. ID: 19900510-2. Zebra Mussel Sightings in Wisconsin SUPERIOR - In late April 1990, Wisconsin Department of Natural Resources biologist Dennis Pratt found 18 zebra mussels on eight of 20 buoys from the Superior-Duluth harbor shipping channel. This was the first confirmed sighting of zebra mussels in Lake Superior. (An unconfirmed sighting at Thunder Bay, Ont., was reported earlier this year.) MILWAUKEE - In early April 1990, a routine inspection of the U.S. Environmental Protection Agency research vessel Roger Simons, overwintering in Milwaukee harbor, found zebra mussels in the ship's water intakes. This vessel had spent time in Lake Erie during 1989, and it had already traversed Lake Erie and several other Great Lakes by early May 1990. STURGEON BAY - The first confirmed sighting of zebra mussels in Wisconsin occurred at Bay Shipbuilding here in late summer 1989, when zebra mussels were found on a barge belonging to a Michigan-based company that had been in service on Lake Erie. Zebra mussels were also discovered at the same location a short time later on the U.S. Coast Guard Lake Erie icebreaker Neah Bay from Cleveland. (An earlier report of zebra mussels on a buoy in Green Bay could not be confirmed.). ID: 19900510-3 . Status Elsewhere First discovered in June 1988 in Lake St. Clair near Detroit, the zebra mussel quickly established itself in western Lake Erie and has since spread downstream to Lake Ontario and the St. Lawrence River. Zebra mussels have become established near several locks in the St. Lawrence Seaway System, including the Snell and Eisenhower locks. By late 1989, the water utility and Detroit Edison power plant in Monroe, Mich., nearly had to shut down when they found their Lake Erie water intakes clogged with billions of zebra mussels. Monroe water department officials spent nearly $500,000 in emergency repairs to remove the mussels, which had reduced water intake flows by nearly 25%. Zebra mussel coverage on buoys retrieved by the U.S. Coast Guard last fall from Lakes Erie and Ontario showed a gradual decrease from west to east, ranging from 100% coverage on buoys from the Detroit River, Maumee Bay near Toledo and at Sandusky and Huron, Ohio, to 80% coverage at Cleveland; 60% at Ashtabula, Ohio; 20% at Erie, Pa.; 5% at Buffalo, N.Y., and 0% at Niagara and Oswego, N.Y. These buoys were on station from spring through fall, and coverage was reported as very uniform at each location. ID: 19900510-4. Wisconsin Sea Grant Monitoring Project Wisconsin Sea Grant is funding a project designed to monitor the Wisconsin waters of Lakes Michigan and Superior for zebra mussel veligers (the free- swimming stage that ranges from 60-250 microns in size) and the young mussels that "set" on artificial substrates and natural hard surfaces. The project has three objectives: (1) determine the presence and rate of colonization of zebra mussels in Wisconsin waters of Lakes Michigan and Superior, (2) disseminate up-to-date information on the presence and spread of zebra mussels in the Great Lakes to lake users and resource managers, (3) develop and test appropriate sampling protocols and levels of effort to detect zebra mussels in early stages of colonization. Vertical plankton tow samples will be collected in harbor areas and analyzed for veligers. Artificial substrates constructed from PVC pipe will be used to observe the presence of mussels that have set. Sampling will concentrate on eight major Wisconsin Great Lakes harbors (Superior, Ashland, Sturgeon Bay, Green Bay, Kewaunee, Port Washington, Milwaukee and Racine) and on nearshore areas likely to be exposed to traffic that can transport adult zebra mussels, such as boats from Lake Erie. Wisconsin Sea Grant is also offering analytical services to public electric and water utilities and to industries that draw water from Lakes Michigan or Superior to inspect intake samples for veligers. Agencies interested in using similar procedures for zebra mussel monitoring, including designs for substrate and water intake samplers, should contact Clifford Kraft (Wisconsin Sea Grant Advisory Services Bldg. ES-105, UW- Green Bay, Green Bay, WI 54311-7001; phone: (414) 465-2795) or Wisconsin Sea Grant Advisory Services headquarters (see Introduction). ID: 19900510-5. Available Publications The Zebra Mussel, Dreissena polymorpha: A Photographic Guide to the Identification of Microscopic Veligers (February 1990), by Gordon Hopkins, Limnology Section, Water Resources Branch, Ontario Ministry of the Environment. This publication provides a guide to the preservation and identification of the early life stages of the zebra mussel. For copies, contact Ron Griffiths (address in "For More Information...", topic 19900510-8). Dreissena polymorpha: An Unwelcome New Great Lakes Invader (November 1989; revised February 1990) by Charles O'Neill, Jr., and Dave MacNeill, New York Sea Grant Extension Program. This eight-page fact sheet describes the origin, biology, impacts and control of zebra mussels. It is available free of charge from New York Sea Grant Extension (see MacNeill address in "For More Information...", topic 19900510-8) and from Wisconsin Sea Grant Advisory Services offices in Madison, Milwaukee, Green Bay, Sister Bay and Superior. Zebra Mussels in Lake Erie: The Invasion and Its Implications (December 1989) by Fred L. Snyder, Ohio Sea Grant College Program. This four-page fact sheet describes the zebra mussel invasion of Lake Erie, related biological and ecological concerns, industrial and commercial concerns, the potential for its spread to inland waters and current research efforts. Single copies are free; multiple copies, 25 cents each. Available from Ohio Sea Grant, 1314 Kinnear Rd., Columbus, OH 43212-1194, phone (614) 292-8949. The Zebra Mussel, Dreissena polymorpha: A Synthesis of European Experiences and a Preview for North America (July 1989), a report prepared by G.L. Mackie, W.N. Gibbons, B.W. Muncaster and I.M. Gray for the Water Resources Branch, Great Lakes Section, Ontario Ministry of the Environment. The title of this 76-page report just about says it all. It is a comprehensive report on the biology of the zebra mussel and European control methods. Free copies of the report are available from Kathy Morch at the OMOE Water Resources Branch in Toronto, phone (416) 323- 4913. ID: 19900510-6. Upcoming Conferences * A Zebra Mussel Symposium will be held in connection with the annual meeting of the North American Benthological Society, May 22-25, at Virginia Polytechnic Institute and State University, Blacksburg, Va. Sixteen technical presentations will be given by scientists actively involved in North American research on the zebra mussel. * A special session on exotic bivalves will highlight the annual meeting of the American Society of Limnology and Oceanography on June 12 at the College of William and Mary, Williamsburg, Va. Sixteen technical presentations will be given, half on zebra mussels and half on the Asiatic clam, another nuisance bivalve. ID: 19900510-7. For More Information... The zebra mussel problem transcends state and national boundaries, and the free exchange and pooling of the knowledge and experience gained in dealing with this new invader is essential to effectively dealing with it. We invite reports of sightings and practical experiences with zebra mussels to be sent to the Wisconsin Sea Grant Advisory Services field office at UW-Green Bay. We will, in turn, try to convey this information to all interested audiences. The public is asked to report any sightings immediately to Wisconsin Sea Grant, the Wisconsin Department of Natural Resources or the U.S. Fish & Wildlife Service. Individuals working on various problems related to zebra mussels in other states and Canadian provinces include the following: * Ron Griffiths, Ontario Ministry of Environment, Southwestern Region, 985 Adelaide Street South, London, Ontario N6E 1V3, Canada, phone (519) 661- 2200. Griffiths is familiar with Canadian programs related to the spread of zebra mussels. * Don Schloesser, U.S. Fish & Wildlife Service, National Fisheries Research Center, 1451 Green Rd., Ann Arbor, MI 48105, phone (313) 994-3331. Schloesser helped organize early workshops on zebra mussels and is involved in studies of their ecological impact. * Dave MacNeill, New York Sea Grant Extension, 405 Administration Bldg., SUNY College, Brockport, NY 14420, phone (716) 395-2638. MacNeill helped organize a workshop and coauthored a fact sheet on zebra mussels. He is also familiar with the spread of zebra mussels into Lake Ontario. * Fred Snyder, Ohio Sea Grant, Room 12, Bldg. 3, Camp Perry, Port Clinton, OH 43452, phone (419) 635-4417. Snyder authored a zebra mussel fact sheet and is active in Extension efforts designed to help boaters deal with zebra mussels. Many other individuals in the region are also working on zebra mussel- related problems, but the people on this list are among the key contacts. We will add more names to this list as they come to our attention. ID: 19900510-8. Keywords: Basic_biology, Monitoring, Veliger |