Thunder Bay National Marine Sanctuary
Continuing from our successful collaborative survey of 153 square kilometers of sanctuary lakebed in 2019, the 2021 exploration project will explore priority areas of the 4,300 square mile Thunder Bay National Marine Sanctuary (TBNMS) with both multibeam mapping and ROV exploration. Working onshore and offshore of Alpena, Michigan, we acknowledge the traditional and contemporary homelands of the people of the Council of Three Fires, the Ojibwe, Potawatomi, and Odawa.
Located in Lake Huron, TBNMS was established in 2000 to protect one of the nation’s most historically significant collections of shipwrecks. Within this boundary are 99 known shipwreck sites, while historic research indicates as many 100 additional sites in the area remain undiscovered. Submerged archaeological sites within TBNMS are a nearly complete collection of Great Lakes vessel types, from small schooners and pioneer steamboats of the 1830s to massive industrial bulk carriers that supported America’s heavy industries during the 20th century.
Mapping will be conducted with multibeam sonar on the University of New Hampshire’s autonomous surface vehicle (ASV) BEN . The bathymetry and backscatter data will be used to produce lakebed habitat maps to understand the condition of coastal Lake Huron’s ecosystems, and for navigational charts.
An ROV from the University of North Carolina Wilmington’s Undersea Vehicles Program will be deployed from USCG Mobile Bay to explore and document the most recent shipwreck discoveries in sanctuary waters. These deep-water sites include the cargo schooner M.F. Merrick and coal freighter Etruria, both discovered in 2011, as well as the steel-hull freighter Choctaw and wooden bulk carrier Ohio, discovered in 2017. In addition to the potential discovery of historically significant shipwrecks, sanctuary waters in Lake Huron also hold the potential for unique natural features such as sinkholes with links to ancient ecosystems, glacial features of interest, and important fish habitat. Survey information and products will support exploration and management of the only freshwater national marine sanctuary in the United States, and will provide new and important information for archaeologists, biologists, and geologists.