Researcher warns bigger northern fires could chip away at biodiversity

Wildfire in Saskatchewan is usually measured in smoke columns, evacuation orders, and blackened hectares.

But University of British Columbia postdoctoral fellow Aaron Bell says another story is unfolding inside the boreal forest itself, one that is harder to see from the roadside or the daily firemap.

Bell, who completed his PhD at the University of Saskatchewan and grew up in La Ronge, said wildfire is not simply a destructive force in the north. It is also a natural part of the boreal ecosystem, one that has long helped shape the mix of plants, birds, and insects found across northern forests.

The concern, he said, is not fire by itself. It is the changing pattern of fire.

“We’re kind of seeing this big transition in how fire is behaving on the landscape,” Bell said.

From his perspective, bigger and hotter fires are reducing the amount of unbound habitat left behind, especially older forest patches that many species rely on and that can take generations to develop.

“It’s really the old-growth habitats that are probably at the biggest risk,” he said.

Bell recently spoke with the Daily Herald about his work studying biodiversity and wildfire patterns in northern Saskatchewan, including research on lake islands in Lac La Ronge Provincial Park. He said islands offered a rare way to study long fire histories clearly because each island is distinct and naturally seperated by water.

That gave researchers a broad timeline, from islands that had burned recently to others that had not burned in more than 230 years.

Bell and his co-authors looked at birds, plants, and beetles, trying to understand which ideas best explain biodiversity in fire-prone boreal landscapes. He said the strongest support came from what is known as the pyrodiversity-biodiversity hypothesis, the idea that variation in fire patterns across space and time helps support a wider range of life.

In plain terms, not every fire is the same, and not every part of the forest should look the same afterward.

Different fire sizes, intensities, frequencies, and timings help create different habitats. Some species do well in recently burned areas. Others depend on long stretches without fire. When those patterns remain varied, biodiversity is stronger. When fires become too large and too uniform. Bell said that variety starts to shrink.

The matters in Saskatchewan, where the scale of recent wildfire season has raised concerns not only about safety and response, but about what repeated severe fire years could mean for the forest in the long run.

During an April 8 technical briefing, Saskatchewan Public Safety Agency vice-president Steve Roberts said the province recorded more than 500 wildfires in 2025 and nearly three million hectares burned. Roberts also said more than 50 communities were evacuated during last year’s season.

Bell said the biological effects of repeated large fires may take longer to show, but some risks are already clear.

One is reburning.

He pointed to areas north of La Ronge that burned in 2015 and then burned again in 2025, leaving too little time for parts of the forest to recover properly.

“If you do have an area that burns multiple times before regeneration can sort of take place and recovery is allowed to play out, I think that can definitely be detrimental,” Bell said.

That can mean the forest that returns is not the same one that was there before. In some regions, intense fire can damage seed sources or alter what species come back first, changing the long-term makeup of the landscape.

Bell said old-growth forests, peat-rich areas, and long-unburned refuges deserve more attention in that conversation, both for biodiversity and for climate reasons. Those areas can store large amounts of carbon, and once they burn deeply, the losses are difficult to reverse.

He also offered a more complex view on human-caused fires. Bell said it is true that some fires are started by people and that caution remains critical, especially during dry conditions. But he said the larger issue is that climate change and long-term fuel buildup are creating conditions where any ignition, whether human or natural, can become harder to contain.

He said Saskatchewan’s fire response system largely focuses on “valued assets” such as communities, infrastructure, and private property. Those priorities are understandable, he said, but they can leave biodiversity, land relationships, and older ecological values out of the equation.

“I really think in the context of how we might change things, or how we might conserve those old-growth forests, we need to sort of broaden our definition of valued assets,” Bell said.

That idea also reaches beyond the trees themselves.

Bell has studied pyrophilic beetles, insects specially adapted to recently burned areas. In one earlier study based on fires east of Prince Albert, he found some ground beetles quickly colonized freshly burned soil because heat from fire had reduced tiny predators that would otherwise feed on their eggs. In that short-lived post-fire window, reproductive success improved sharply.

For him, it is one more reminder that fire is deeply built into boreal ecology, even if today’s changing fire behaviour is creating new pressures.

Bell said people across Saskatchewan still have an important role to play. Follow fire bans, use FireSmart practices, and be cautious with campfires and other ignition sources, he said. But he also believes the province needs to think seriously about prescribed burning and cultural burning as tools to reduce fuel and lower future risk.

“The world is changing in a kind of dramatic way,” Bell said. “The business as usual approach, where we don’t really value biodiversity, is outdated.”

arjun.pillai@paherald.sk.ca