Dr. Catie Ivy doesn’t call the birds she studies “birds”—she calls them her friends. And she wonders if her friends might be in danger due to smoke from recent wildfires.

“The major question is, what does wildfire smoke mean for songbirds? And for migratory birds, what does it mean for their ability to migrate?” she says.

An assistant professor of biology with the University of Saskatchewan (USask) College of Arts and Science, Ivy is leading a research project that will examine the physiological effects of smoke intake on songbirds.

Wildfires in Canada have increased in scale in recent years. The 2023 wildfire season was the worst ever recorded in terms of area burned, followed closely by the 2024 season. As Ivy puts it, there is anecdotal evidence about birds being affected by wildfire smoke, but there isn’t much scientific research to accompany it. By tracking bird population migrations and conducting lab research, her study aims to identify the overall effects of long-term smoke inhalation for birds.

While Ivy and her team don’t expect to find that a single large wildfire event causes serious smoke-related issues for birds, she says the concern arises from repeated events and exposures. If prolonged smoke exposure affects birds’ physiology, it could also influence their ability to migrate, in turn altering bird populations, if young birds cannot make the trip.

“It’s important for us to know because we can be cognizant of why population declines might be happening, or why we might expect declines,” she says. “Even being able to understand the magnitude to which (smoke) stresses birds is important.”

Ivy describes the difference between bird lungs and human lungs as “tubes” versus “grapes.” In humans, air travels through a branching bronchial tree into tiny sac-like alveoli—which are clustered like grapes—where gas exchange takes place. In birds, by contrast, air flows through a fixed set of narrow tubes called parabronchi inside the lungs, supported by a system of air sacs that keep air moving in one direction. This tubular airflow system makes respiration more efficient in birds than it is in mammals. A bird’s respiratory system must be as efficient as possible for intensive tasks like migratory flight, which Ivy says is even more “aerobically demanding” than running is for animals.

In fact, another project of Ivy’s that was funded by an NSERC Banting Postdoctoral Fellowship explored how songbirds’ respiratory systems and overall physiology undergo seasonal changes to build the stamina needed for migration. One important change involves taking slower, deeper breaths to enhance oxygen uptake.

“A lot happens for birds between being a couch potato in the non-migratory season and becoming, essentially, an endurance athlete. What we’re really interested in is how wildfire smoke is going to interact with those changes,” Ivy says. “Another way of looking at it is: if I were to suddenly start smoking, would I still be able to run the marathon?”

The research team is exploring the effects of wildfire smoke on birds in multiple ways. For example, they are examining individual birds to see how those who were exposed to smoke are physically affected compared to those who were not. The team is also tracking migrating birds to see if their travel patterns change due to smoke.

The project received support from NSERC’s Discovery Grants program, which funds longer-term post-secondary projects that aim to advance research in key areas.

As a newer faculty member at USask, Ivy says receiving NSERC support for this project was “huge,” allowing her to bring in students and pursue a far-reaching research program. She credits USask and NSERC for their support in getting the project off the ground.

“It means I can take on students and get different parts of the project on the go. It also means that NSERC saw value in this research and in supporting an early-career researcher.”

This article was adapted and published with permission from the University of Saskatchewan.