Getting to the Bottom of Blue-Green Algae in Northern Ontario Lakes

Published in The Chronicle Journal on March 12, 2026

By EMILY DONTSOS

A quiet threat is slowly emerging in northern Ontario’s lakes—and Lakehead PhD candidate Nathan Wilson is determined to get to the bottom of it. 

Commonly known as blue-green algae, cyanobacteria blooms are increasingly present in the region’s waters. A sign of an out-of-balance ecosystem, cyanobacteria can also produce dangerous liver and neurological toxins that put human and animal health at risk. 

But regular monitoring of the lakes has been virtually non-existent. It was believed that their cold temperatures and lack of human activity meant that they were healthy and pristine.

This assumption allowed cyanobacteria to grow unnoticed. 

That is, until now. 

Under the supervision of Dr. Robert Stewart, associate professor in geography and the environment, Wilson is working to understand what’s causing this change and what can be done to stop it.  

A Growing Body of Evidence 

Wilson first spotted cyanobacteria blooms a decade ago while sampling lake water for his Lakehead University master’s project. 

“When I saw cyanobacteria under a microscope for the first time, I realized how little monitoring is actually done in northern Ontario’s lakes,” he says. “So many unanswered questions emerged from that work, and it’s become a passion of mine to figure it out and raise awareness about this issue.” 

Wilson has spent years collecting samples from remote lakes with the support of lake associations, cottage owners, First Nations communities, and fishing groups as well as individuals who’ve contacted him after spotting blooms. 

Using environmental DNA analysis, he has been able to track changes in the presence of cyanobacteria over time. 

“Nathan’s research shows that the issue is not just about researchers becoming more aware of the problem; there is evidence that cyanobacteria actually has been steadily increasing,” says Dr. Stewart, who has been supervising Wilson’s research since his master’s project. 

Wilson’s research points to both climate change and increasing human activity as key factors in the presence of cyanobacteria. Warming temperatures have disrupted the nutrient balance, while pollution and waste have only exacerbated the problem. 

Despite this growing threat, Wilson and Dr. Stewart say governments have been slow to act. Compared to lakes in southern Ontario, which face significant challenges when it comes to pollution and the impacts of climate change, northern Ontario’s lakes are deemed less of a concern. 

“We’re still living in a system that believes these cold lakes just don’t change,” Dr. Stewart says. “Nathan’s work highlights that things are changing, and we need to invest the money, time, and political will to care for these lakes more seriously.” 

Advocating for Citizen Science and Collaboration 

Regular sampling is required to fully understand and address the presence of cyanobacteria blooms in northern Ontario lakes. But Wilson recognizes that monitoring thousands of lakes across vast distances is not feasible for government agencies. 

That’s why he’s advocating for the formal inclusion of citizen scientists in the region’s monitoring practices. 

“Right now, the government does not typically accept water samples collected by members of the public, which is a major missed opportunity,” he says. “We need accessible, low-barrier participation. Anyone concerned about the health of these lakes should be allowed to provide samples.” 

Wilson and Dr. Stewart are also calling for monitoring standards that are specific to the north and that emphasize collaboration between the government and the public. 

Most of all, Wilson wants northern Ontario residents and visitors to know the region’s lakes are not doomed. 

“Cyanobacteria is a critical threat, but it’s manageable,” he says. “We just need to recognize what’s happening and adjust how we interact with the system.”  

Nathan Wilson’s research project closely aligns with United Nations Sustainable Development Goals on Good Health and Well-Being (#3), Clean Water and Sanitation (#6), Responsible Consumption and Production (#12), Climate Action (#13), and Life Below Water (#14). 

Learn more and get involved at bluegreenlabs.ca. 

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