Superior Shoal under the microscope: Is it the key to understanding the Great Lakes ecosystem?

Imagine a giant mountain of volcanic rock, completely submerged in water and located in the middle of an inland ocean.

This description pretty much sums up Superior Shoal , An underwater mountain that rises approximately 300 meters above the bottom of Lake Superior.

First chartered in 1929, Superior Shoal is also entirely within the world’s largest freshwater conservation area and is 70 kilometers from the nearest shoreline. Its remote location in the center of Lake Superior has made it somewhat of a mystery.

Look Superior Shoal in the middle of Lake Superior:

However, a research team from Lakehead University in Thunder Bay, Ontario, and a film crew explored the coast in early September. The expedition was tasked with collecting valuable data about the role of this huge underwater structure on the lake’s ecosystem.

The shoal is a unique structure that could play an important role in understanding Lake Superior’s ecosystem, said Michael Rennie, an associate professor at Lakehead University and research fellow at the International Institute for Sustainable Development-Experimental Lakes Region.

“It’s a unique place and it’s a crazy mountain in the middle of Lake Superior,” Rainey said. “There are few other places like this in the Great Lakes, and what we’ve learned is like seamounts in the oceans, these are hotspots of biodiversity and fish productivity.”

The expedition members spent 9 days on a trawler

Supported by a grant from the Canadian government, Rennie and his six-member science team traveled to Superior Shoal from Duluth, Minn., on a research ship called the Blue Heron.

The team worked and slept on an 83-foot trawler during the nine-day expedition. Renee said there was a lot to do during that time.

“One of the things we were trying to understand on the Superior Shoal is how physical processes like currents, waves, and light penetration interact with the biological community, and how that might be involved in supporting the biological community that exists here,” Rainey said. “Some of those physical processes include deposition of material from the water column as well as deposition of water through back eddies and currents that move over the shoal.”

The Superior shoal can play an important role in the health of the Lake Superior trout fishery, Rainey said, noting that redfin, lean and ciscowet are among the many unique species of lake trout that call the shoal home. These stocks also survived the fisheries crash caused by lamprey and overfishing in the 1960s and 70s, he said.

“Nobody ever fished these places like Superior Shoal,” Rainey said. “And those populations have more or less recovered on their own. So are these fish genetically the best representation of the lake trout that used to be in Lake Superior before the decline in the ’60s?”

Filmmakers take advantage of ‘rare’ opportunity

Although Rennie’s research was the focus of the expedition, the entire nine days were also documented.

The Blue Heron was also carrying filmmakers from Bruce County in southern Ontario.

Yvonne Drebert and Zach Melnich are the award-winning duo behind Inspired Planet Productions and are both Fellows of the Royal Canadian Geographical Society.

“We basically begged Michael to take us,” laughed Melnick. “This area has very rarely been seen on camera.”

Melnick said he was curious about Lake Superior shoal-like bulges after discovering the lake during the filming of his series and related documentary. All Clear: Beneath the Surface of the Great LakesThat documentary examined how invasive zebra and quagga mussels have changed food dynamics in the Great Lakes.

The filmmakers also wanted to see if they could film certain trout species that are an important part of Lake Superior’s fisheries.

“When we got to Superior Shoal the one fish we were expecting to see was redfin,” Drebert said. “And it’s a lake trout with huge fins, a big tail and a gorgeous red color. And we think the redfin sails around these underwater mountains using their giant fins, the way eagles fly around a mountain using the upward-flowing currents.”

‘Super cool’ use of underwater robot

To get to the required depth off the coast, and with the best clarity possible, the filmmakers used a 27-kilogram, high-tech underwater robot. , or remotely operated vehicle (ROV).

The front of the ROV has an acrylic dome that can handle intense pressure when going deeper. It also corrects underwater optics and has the same type of camera used for filming animals in moonlight.

This robotic drone, built in partnership with Boxfish Robotics in New Zealand, can go to a depth of about 500 meters and has eight thrusters. Melnik said the robot can stay underwater for hours and swim like a fish.

“We also try to mimic the behavior of the fish with the robot,” Melnick said. “We found that the lake trout, especially in the Superior Shoal, were very friendly with the robots. So they would come and be curious, and watch it just like you imagine, like a seal or something else might be in the ocean. And so that was great.”

Drebert said you can’t send signals through water the same way you can through the air with an aerial drone, so the ROV is always connected via fiber-optic wire. On the Blue Heron, Drebert will feed the tether and Melnik will control the ROV from a room full of screens. From here, he could drive the ROV, view what was being filmed and keep track of the location via GPS.

Melnick said the footage shot on Superior Shoal will be part of a new series Hidden below: Freshwater World He says he’ll be coming to TVOntario in a few years. He said they are also making a science documentary that will explore the importance of seamounts and why they should be protected more, just as seamounts are protected in the oceans.

Drebert said the discovery of Superior Shoal revealed its size and vastness.

“I think people who are living in Thunder Bay or Nipigon, looking at the archipelago and looking at the Pacific Islands and how they’re structured, they imagine it’s all going on underwater, in the depths,” she said. “It was really cool to imagine what these mountains actually look like.”