Ongoing research on lake sturgeon in both the Rainy Lake and Namakan systems was one of the main highlights at the Rainy Lake Conservancy’s annual general meeting this past Sunday at La Place Rendez-Vous here.
Lake sturgeon have existed in this region for 136 million years—and through multiple ice ages, marvelled the afternoon’s guest speaker, Brian McLaren, an associate professor in the Department of Natural Resources Management at Lakehead University in Thunder Bay.
“It’s just interesting to think about this scale,” he said about the fish which currently is considered a species at risk.
McLaren first became involved with research on Rainy Lake years ago through Voyageurs National Park’s research on beaver, as well as taking students on field trips.
From there, he became involved with the joint project between VNP and the Ontario Ministry of Natural Resources to study the lake sturgeon population and migration routes with implanted transmitters.
Interested in lake sturgeon habitat, McLaren told those on hand for Sunday’s meeting how RLC funding to purchase a $2,000 underwater camera has helped with this research.
“The camera has a pressure rating—that’s what makes it expensive—a pressure rating that allows it to go down to hundreds and hundreds of feet,” he explained.
“We allowed it to go down to about 100 feet because, as you know, this lake is pretty shallow.”
Using the camera, which is set to take a photo every two seconds, McLaren and the other researchers are able to see what kind of substrates—or lake bottom—exists.
“We know, for example, that this sandy substrate, this sand here,” he said, pointing to one photo, “is what’s more attractive to lake sturgeon because it’s what supports the insects, mussels, crayfish, and things that are the typical part of the lake sturgeon diet.
“So we’re able to count the amount of gravel, count the amount of sand,” he noted.
This type of research is connected to taking good care of the lakes and oceans of the world, McLaren argued, speaking as a Canadian from the East Coast.
“If you don’t know [what’s underwater], you don’t know how to protect it,” he stressed.
McLaren also has been supervising two graduate students—Matt LeBron and Cam Trembath—on lake sturgeon research, another area he spoke about Sunday.
As an honours thesis student, LeBron had “developed maps—and took the Rainy Lake shoreline and modelled slope and exposure and so on and actually did a really good job of predicting where the most likely lodges were that would house beaver colonies for four, and five, and six years in a row.”
This is something he’s now applying to the foraging areas of lake sturgeon, noted McLaren.
LeBron has been “surveying different features of the shoreline in the south arm, both the Canadian and the U.S. side, and matching up the lake bottom to physical features that he can read from digital air photos or topographic maps, and trying to get an idea of what’s living under the water,” McLaren explained.
McLaren said we’ve got a unique opportunity to study juveniles here.
“For one thing, they’ve never been netted here,” he explained, noting that the Minnesota DNR, Ontario MNR, and park services in the area put out the gill nets in the areas where they are more likely to catch walleye and other sport fish.
Trembath has been able to find where juvenile sturgeon reside—not along the shorelines like the adult sturgeon do but at deeper, 20 metres in depth often, since they are more vulnerable to predators.
With this, they have been throughout the lake systems collecting data on the juvenile sturgeon, said McLaren, presenting a slide show of pictures they have been taking alongside this project.
“Just last week, 132 fish were eventually caught—all under or about a pound,” he noted, adding that Trembath’s “criteria” for juveniles are that they’re less than 550 grams and at least a year old.
It was during this research they also discovering the significance of High Falls on the Namakan system when it comes to juvenile lake sturgeon.
“In fact it’s right here, just below the falls, that most of the juvenile sturgeon big enough for Cameron to connect the transmitters to—most of them hang out just below the falls,” McLaren said
“In fact, most of his captures—90 of 132 captures—were at Bill Lake, just below at Quetico Rapids, and just about High Falls, and that was very interesting.
“He visited Kettle Falls, he checked many places around Namakan Lake,” McLaren added.
“The only place he [Trembath] could catch juveniles in the lake was below the Namakan River.”
High Falls is one of the proposed sites for the Ojibwe Power Corp.’s proposed hydroelectric dam project—a project the RLC and other organizations have spoken out against.
McLaren also touched upon the history of Lake Agassiz—the ancient lake that covered this whole region before draining away 7,500 years ago, leaving behind Rainy Lake, Lake of the Woods, Lake Winnipeg, Lake Winnipegosis, and others—and the effect this lake has had on the area’s geography and habitats.
As a part of the RLC’s business meeting Sunday, members elected its board of directors—with Candy Ginter and Christopher Causey as new faces to the board joined again by Don Dickson, Kay Larsen, and Ginny Sweatt.
Taking over as president this year from Dale Callaghan will be Stephen Challis.