The zebra mussel is a small freshwater animal, about the size of a thumbnail. Native to the lakes of eastern Europe, it is considered an invasive species in North America. The zebra mussel is believed to have been introduced to the Great Lakes on the hulls or in the ballast water of vessels from Europe. Voracious eaters, the mussels tend to consume all the phytoplankton of a specific size within an area, which, in turn, starves other species depending on that food source. This results in a cascade effect, in which entire populations of native animals starve to death. By out-competing, they have eliminated native mussel species in locations around the world. The zebra mussel is also a prolific multiplier -- females produce between 30,000 to 1,000,000 eggs per year. The zebra mussel attaches itself to any available hard surface, including other mussels. They make their homes in water treatment plants, power plants and boat engines, among other places, causing no end of problems. Their tissues can also accumulate high concentrations of pollutants, which they then release back into the water in the form of waste, posing a health hazard to both other marine life and humans.
Thunder Bay National Marine Sanctuary
• Official Web Site (at thunderbay.noaa.gov)
• Shipwrecks of the Thunder Bay Region (at thunderbay.noaa.gov)
In the early 1970s, inspired by the wide array of shipwrecks under the waters of Thunder Bay, members of local diving clubs and civic groups in Alpena, Michigan, started to express interest in establishing an underwater park. With the support of these individuals, in 1981, Thunder Bay became one of Michigan's first underwater preserves. At around the same time, residents of Alpena submitted a proposal to the NOAA for sanctuary status. The evaluation and approval process ended with the designation of Thunder Bay National Marine Sanctuary in 2000.
Located in the waters of Lake Huron, off the east shore of northern Michigan, Thunder Bay National Marine Sanctuary is home to a significant collection of more than 100 shipwrecks. The lake's cold, fresh waters create an excellent environment for shipwreck preservation that is unmatched by saltwater environments. The shipwrecks of Thunder Bay represent the diversity of commercial shipping vessels that navigated the Great Lakes from the earliest expeditions in the 19th century to modern-day trade. The collection illustrates transitions in ship architecture and construction, from wooden schooners to early steel-hulled steamers, and includes several unusual vessel types. The wrecks, which lie between 12 and 180 feet deep, range from largely intact ships to mere remnants of boats. It is believed that many wrecks still remain undiscovered.
The range in depth of the shipwrecks in Thunder Bay makes them accessible to divers with a variety of skill levels as well as to nondiving visitors. Snorkelers can see some of the shallower wrecks, which are also viewable from kayaks and glass-bottomed boats.
INSIDE THE SANCTUARY
- The sanctuary is undertaking a complete inventory of Thunder Bay's shipwrecks. Techniques used in documenting the wrecks include sonar, remotely operated vehicles, video and site mapping.
- In partnership with the county library, the sanctuary is preserving the entire Thunder Bay Sanctuary Research Collection by digitizing tens of thousands of photos, vertical files, data cards, navigation charts, shipbuilding plans and other materials.
- Installed a permanent mooring buoy system to identify and protect shipwreck sites
- Opened the Great Lakes Maritime Heritage Center, a state-of-the-art building featuring a 93-seat theater, 9,000 square feet of exhibit space, distance-learning equipment, an artifact conservation laboratory and visible curatorial space
- Acquired the research vessel, Huron Explorer, the first U.S. vessel to use all-natural oil-based fuel and lubricants
- Installed an Integrated Coastal Observing System buoy at the shipwreck Montana, providing real-time meteorological data and real-time shipwreck imagery
- Began moving 800 objects recovered from shipwrecks in Michigan waters to the Great Lakes Maritime Heritage Center
- Used Live Dive and Telepresence technologies to allow nondivers to experience the sanctuary's shipwrecks without getting wet
- Provided educational opportunities for regional teachers and students, including educational activities on tall ships and training for an international competition in the building of remotely operated vehicles
- Partnered with local emergency response groups to conduct on-the-water drills to improve public safety