Biologist Steeve Côté has seen forest fires engulf parts of the province of Quebec before and he knew it would happen again. He just didn’t expect it so soon.
Not long after the biology professor at Université Laval and its centre for northern studies began his career, he witnessed the 1991 fires that destroyed parts of Quebec near Baie-Comeau on the North Shore.
Back then, Environment Canada reported that upward of 350,000 hectares of forest had been destroyed. Côté says it has since recovered.
Côté says fires of that intensity typically happen every couple of centuries but right now, only 30 years later, 300,000 hectares of forest are being razed by about 150 wildfires — twice as many as usual, compared to the province’s 10-year average.
Côté says that in some ecosystems — in Australia, for instance — fires can happen almost every year.
“But in other places like in the boreal forest in eastern Quebec, like north of Sept-Îles and the North Shore, the frequency is very, very long: it’s every 150 to 200 years or so.”
More frequent fires can pose a challenge to wildlife. While many species are adaptive and will bounce back, experts say with so much forest burning, animals, insects — and the boreal forest itself — could be destabilized for years to come.
Smaller animals can’t outrun fire
Côté says the fires’ impact on wildlife will vary depending on the species.
“Some species could move away relatively rapidly — like birds for instance — and the large mammals as well, like wolves and moose and deer,” said Côté.
“But for the smaller species, especially the small mammals that are quite often at the base of the food chain, it’s a lot more complex. They cannot move really fast. The fires sometimes … they can go up to 50 metres a minute. This is too fast for small mammals.”
He says not much research has been done on animals’ survival instincts during wildfires but some inevitably die, while others may try to burrow underground to escape the heat.
Recovery could take years
Animals that do manage to escape a major forest fire could struggle to survive in their new location, said Côté.
“They’re used to a certain habitat. So they have to find a new place, they have to find the resources they need,” said Côté.
But they will be new arrivals in an already established ecosystem and will have to compete for resources.
“If their food sources have burned, they have to find new sources and for some species it takes a lot of time to learn it.”
He says typically wildfires last days to weeks, but with Quebec’s current fires possibly lasting into the summer, it “may take years for the habitat to recover.”
After the fire: some insects help, others invade
Maxim Larrivée, the director of the Montreal Insectarium, says insects can play a major role in regenerating a forest after a fire, helping decompose the charred trees.
Some species flourish if their predators have left the area.
“There will be no animal, no parasites that can attack them because they’ve been killed by the wildfire,” said Larrivée. “So they’ll be able to reproduce and their population will grow faster,” said Larrivée.
While insects are normally an important food source for other species, the overabundance of some insects can result in a cycle that worsens future wildfires.
“In this case, epidemics of spruce budworm and of other insects that could kill patches of forest and then turn them into fuel for future wildfires,” said Larrivée.
“That creates more fuel for those fires to burn even longer, burn even more intensively and those epidemics [of insect species] have been bigger and bigger because the conditions [are] created by the spruce budworm.”
Frequent massive wildfires could destabilize the biodiversity of Quebec’s boreal forests, Larivée said.
“Boreal forests depend on what we call a mosaic of different types of habitat,” said Larrivée. “If you have more frequent, more intense and bigger wildfires, certain elements of old growth boreal forest will not exist on the landscape anymore.”
“Unfortunately those are all manifestations of climate change that as a scientific community, we have been warning society were going to happen,” said Larrivée.
“This is just another really unpleasant manifestation of what can happen if we don’t get our act together collectively.”