A massive underwater mountain, known as the Superior Shoal, rises almost 300 meters from the depths of Lake Superior. Discovered in 1929, this unique structure lies within the world’s largest freshwater conservation area, 70 kilometers away from the closest shoreline, making it a mysterious location due to its remote position in the heart of the lake.
Recently, a team of researchers from Lakehead University in Thunder Bay, Ontario, along with a film crew, embarked on an expedition to explore the Superior Shoal in early September. Their primary goal was to gather essential data to understand the role of this underwater mountain in Lake Superior’s ecosystem.
Michael Rennie, an associate professor at Lakehead University and a research fellow at the International Institute for Sustainable Development-Experimental Lakes area, highlighted the significance of the shoal in studying Lake Superior’s ecosystem. He compared it to seamounts in the oceans, emphasizing that such underwater structures are biodiversity hotspots that enhance fish productivity.
The expedition, lasting nine days, was supported by a Canadian government grant. The team, consisting of six scientists led by Rennie, traveled to the Superior Shoal from Duluth, Minnesota, aboard the research vessel Blue Heron. During their time on the trawler, they studied the interaction between physical processes such as currents, waves, and light penetration, and the biological community on the shoal.
The Superior Shoal plays a crucial role in the health of Lake Superior’s trout fishery, hosting unique strains of lake trout like redfin, leans, and siscowet. These trout populations have managed to recover naturally without human intervention, reflecting the ecosystem’s resilience.
Filmmakers from Inspired Planet Productions documented the expedition, capturing rare footage of the underwater environment using a high-tech underwater robot provided by Boxfish Robotics. The robot, equipped with advanced optics, allowed for detailed exploration of the shoal’s depths, revealing fascinating interactions between the lake trout and the technology.
The footage obtained during the expedition will be part of a new television series, “Hidden Below: the Freshwater World,” scheduled to air on TVOntario. The documentary aims to shed light on the importance of underwater mountains like the Superior Shoal and advocate for their protection, similar to seamounts in the oceans. The filmmakers were amazed by the vastness and beauty of the underwater landscape, emphasizing the significance of preserving these unique ecosystems for future generations.
