CASE NUMBER: 166 CASE MNEMONIC: BALLAST CASE NAME: SEA BALLAST AND ZEBRA MUSSELS A. IDENTIFICATION 1. The Issue The introduction of zebra mussels into the Great Lakes ecosystem has created a new set of problems for both industry and environmentalists as they attempt to combat the rise in population of this particular menace. First brought to Lake St. Clair in the ballast of cargo ships, zebra mussels have reproduced at a phenomenol rate. They currently threaten several indigenous species and constantly clog the water intake pipes of water treatment plants as well as nuclear power facilities. 2. Description Freighters frequently carry cargoes other than what is in their holds, and one such example is that of the zebra mussel. In 1986, a ship bound for the Great Lakes emptied its ballast tanks of sea water into Lake St. Clair while waiting to load its cargo of grain. This seemingly harmless action introduced the microscopic larvae of the zebra mussel into the ecosystem of the Great Lakes (Nash, p. 63), which had previously been confined to the water systems of eastern Europe. The zebra mussel is native to the Caspian Sea and has spread throughout the canals, rivers, and lakes of Europe over the past 150 years (Nash, p. 63). Generally, ships take on a certain amount of water as ballast when they have no cargo in order to better handle the oceans while in transit. The water which had been sucked in must then be discharged when arriving at the ship's destination to make room for the ship's cargo. Whatever else has been sucked in with the water is then introduced into a different environment when the ship discharges its ballast. This is how the zebra mussel was first brought into North America. [This is also true of the sea lamprey, the spiney perch, and the alewife (McCosh, p. 63).] Zebra mussels (driessena polymorpha) tend to grow in colonies of anywhere from thousands to millions of individuals. They inhabit smooth surfaces which are easier to adhere to such as clams, boat hulls, pilings, pipes, and bouys (Time, p. 63). This species receives its "zebra" name from the alternating dark and light stripes across its shell which become darker with age. Each mussel is roughly two inches long and lives for a period of five years. The zebra mussel was first detected in the United States in 1988, but probably reached the US in 1986 on board a freighter as mentioned above, based on how large the colonies had become when detected. [It is not until its second year of life that a zebra mussel is capable of being detected because of its microscopic size at younger ages (Stegemann, p. 37).] Female zebra mussels lay approximately 30,000 eggs per year which then become microscopic, floating larvae. It is while in this stage of life that the mussel is most easily spread, whether in bilge water or on the wings of waterfowl (Miller, p. 2334). Zebra mussels provide several benefits to the waters in which they live. A single mussel can filter up to one liter of water per day as a method of obtaining its food (Conservationist, p. 39), which effectively rids the surrounding areas of many pollutants including cadmium and selenium (Omni, p. 29). Mussels can also filter out green-brown algaes, which frequently discolor water. The resulting clear water provides the habitat needed for an increase in the numbers of snails, crayfish, and amphipods which are then eaten as food by other species of gamefish (Cohen, p. 16). However, there seem to be many, more negative aspects of the zebra mussel. The same filter-feeding allows the unchecked growth of bottom-growing seaweed which can then choke water systems. The mussels also filter out plankton which is a primary foodsource for fish and waterfowl (Miller, p. 2334). Zebra mussels outgrow native clam and mussel species by ten to twenty times and attach themselves to other mollusks' shells which then cannot open to feed, in effect strangling them. This is an additional problem because seven of the native Great Lakes clam species are on the endangered species list (Technology Review, p. 15). The largest problems involve where the mussels attach themselves for their five year lives. Zebra mussels have submerged navigational bouys because of the weight of their colonies. More significantly, the mussels pose a serious economic cost to many industries in the Great Lakes area. During 1990, the city of Monroe, Michigan lost power for two days because zebra mussels had clogged the water intakes for the cooling system of the city's power plant. Detroit Edison, a Michigan power company, estimated that it spent $500,000 to correct this problem (Time, p. 63). There are numerous other examples of similar problems. Ford Motor Company was forced to close one of its plants for the same reason. Industries and utilities in Michigan estimate that over a ten year period, they will spend more than four billion dollars to get rid of and control the zebra mussel population (Technology Review, p. 15). The mussels cause obstruction of pipes, corrosion of steel, a loss of efficiency, and the production of large amounts of methane. There are many proposals concerning how to deal with the zebra mussel problem. Divers can physically remove the shells by scraping them from the intake pipes. However, this is extremely expensive, dangerous, and time-consuming. Certain species eat the zebra mussels (which are unfit for human consumption). Black carp could be imported from Asia, farmed in the US, and sold to industry. However, the carp could possibly bring with them diseases which have never been found In the United States before. In addition, these fish could behave in a different manner when put into a new environment and eat other native species such as snails (USA Today: The Magazine of the American Scene, p. 9). Sea ducks are capable of eating the mussels but not in significant numbers. The pumping of extremely hot water through intake pipes can be an effective killer of zebra mussels and is the cheapest option for widespread industry use. The last option is the use of chemicals. Oxidizing biocides, potassium, chlorine, and ozone are all effective at killing the zebra mussels. Regardless of the method used, the problem still remains, to remove the shells of the dead mussels (Miller, p. 2335). The last problem which then must be solved is the disposal of the mussel shells and meat. Landfills will not accept them because of the intolerable odor they create. In addition, many of the organisms are considered to be toxic because of the high levels of contaminants found in their bodies. The most successful plan so far has been the idea of composting the mussels. The state of Michigan is attempting to compost mussels in a manner similar to the method Wisconsin uses for composting fish wastes. Michigan could then use the resulting product for agriculture and horticulture. The shells of the mussels could also be crushed and used as a calcium supplement in animal feed (Omni, p. 29). There are four methods which will be attempted: leaving a static pile under cover, putting a static pile outside, aerating a covered pile, and aerating a pile outside. The results can then be compared to examine which is the superior method (BioCycle, p. 52). These solution may solve the current problem. However, it is still extremely difficult to prevent the spread of the zebra mussel's microscopic larvae. The U.S. Coast Guard now has a regulation requiring vessels to dump their ballast before entering the St. Lawrence Seaway. The problem will hopefully end with the states already affected (Alabama, Arkansas, Illinois, Indiana, Kentucky, Michigan, Minnesota, Missouri, New York, Pennsylvania, Wisconsin, Ontario, and Quebec). However, there is currently a new species of zebra mussel on the horizon which is a larger and hardier cousin of the zebra. It has yet to be determined whether these methods will also work on the larger Quagga mussel (Ward, p. 34). 3. Related Cases 1. Hawaii Case Keyword Clusters (1):Region = NAMER (North America) (2):Bio-geography = OCEAN (Great Lakes) (3):Environmental Problem = POLS (water pollution) 4. Draft Author: William Macon B. LEGAL clusters 5. Discourse and Status: AGRee and INPROGress There is general agreement by the states surrounding the Great Lakes that the zebra mussel represents a serious problem to be dealt with. The exact solution is still being discussed and experimented with. 6. Forum and Scope: USA and UNILATeral 7. Decision Breadth: 1 (USA) The United States is the only country which must deal with the problem of the zebra mussel because eastern Europe already coexists with it and does not see it as a major dilemma. The U.S. must deal with the mussel on a unilateral basis. 8. Legal Standing: NA The only law applicable is the result of the zebra mussel infestation. The U.S. Coast Guard now requires all ships to dump their water ballast before entering the St. Lawrence Seaway. C. GEOGRAPHIC Clusters 9. Geographic Locations a. Geographic Domain: NAMER b. Geographic Site: NNAMER c. Geographic Impact: USA The problem is confined to the continent of North America and more specifically, the United States. 10. Sub-National Factors: YES The zebra mussel problem is not one for the entire United States. Only the eleven states which have detected the zebra mussel or its larvae are affected by its presence. 11. Type of Habitat: OCEAN Technically, the zebra mussel is a freshwater mollusk which cannot exist in saltwater oceans. However, this is the only category under which the subject can be placed. D. TRADE Clusters 12. Type of Measure: REGBAN The Coast Guard has now banned all ships from entering the St. Lawrence Seaway without first dumping their ballast. 13. Direct vs. Indirect Impacts: INDirect The trade in grain or iron ore on the Great Lakes did not directly result in the introduction of the zebra mussel. Trade indirectly introduced the mussel into the ecosystem through the shipping process. 14. Relation of Measure to Environmental Impact a. Directly Related: NO b. Indirectly Related: YES (shipping) c. Not Related: NO d. Process Related: YES (habitat loss) 15. Trade Product Identification: TRANSport 16. Economic Data The major economic problem associated with the spread of the zebra mussel is cost of removal. As stated above, in a single year, the Detroit Edison power company spent $500,000 to keep the water intake pipes clear in Monroe, Michigan. The mussel forced Ford Motor Company to temporarily close one of its plants resulting in a loss of productivity. Over a ten year period, industries in the Great Lakes region estimate that they will spend four billion dollars to clean mussels away from water pipes. 17. Impact of Measure on Trade Competitiveness: NA 18. Industry Sector: SERVices 19. Exporter and Importer: EUROPE and USA The original source of the zebra mussel was in the Caspian Sea of eastern Europe. Although not intentionally exported, Europe must be considered the exporter. The same holds for listing the United States as the importer, although unintentional as well. E. ENVIRONMENT Clusters 20. Environmental Problem Type: POLS The zebra mussel is considered to be sea pollution because: 1) it lives in the ocean, and 2) it is released into an environment in an uncontrolled manner similar to waste disposal. In addition, the species has negative effects within the Great Lakes ecosystem. 21. Name, Type, and Diversity of Species Name: Zebra Mussel (driessena polymorpha) Type: Mollusk Diversity: NA 22. Impact and Effect: MEDIUM and PROD Impact of the mussel is medium based on its threat to native species in the Great Lakes and economic costs. It is the zebra mussel itself (the product) which is the threat to the environment. 23. Urgency and Lifetime: LOW and 5 years The zebra mussel has a lifespan of approximately five years. It is considered to have little urgency because it does not pose a direct threat to the earth or the human race. 24. Substitutes: NA VI. OTHER Factors 25. Culture: NO 26. Trans-Border: NO 27. Rights: NO The zebra mussel problem does not affect culture or human rights. In addition, zebra mussels are not a trans-boundary problem which are the fault of one nation and the problem for another. 28. Relevant Literature Baker, Sherry. "The Redeeming Qualities of Zebra Mussels." Omni, 16 (1994), 28-29. "Chinese Black Carp vs. Zebra Mussel." USA Today: The Magazine of the American Scene, 122 (1993), 9. Cohen, Tracey. "Pests with Redeeming Values." Technology Review, 95 (1992), 15-16. McCosh, Dan. "Aliens Among Us." Popular Science, 246 (1995), 94. Miller, S. in Environmental Science and Technology, 26 (1992), 2334-2335. Nash, J. Madeleine. "Invasion of the Zebra Mussels." Time, 137 (January 21, 1991), 63. Stegemann, Eileen C. "The Zebra Mussel- New York's Carpetbagger." Conservationist, 47 (1992), 37-41. Ward, Janet. "Attack of the Zebra Mussel." American City and County, 107 (1992), 30-36. "Zebra Mussels Enter the Compost Pile." BioCycle: Journal of Waste Recycling, 33 (1992), 52.