Q&A: How some songbirds may be adapting to the effects of climate change

From wildfire smoke to changing temperatures, birds are facing threats from climate change, but there is still much left unknown about its full impacts.

Researchers at Western University's Advanced Facility for Avian Research are looking into how some migratory songbirds can adapt to a changing environment, and push their physiological limits to escape the effects of climate change during migration. 

Afternoon Drive guest host Colin Butler spoke to Catherine Ivy, a postdoctoral researcher to learn more.

The following has been edited for length and clarity.

Colin Butler: What threat is climate change having on bird migration now?

Catherine Ivy: Climate change is coming at birds from many different angles. It's not only warmer temperatures, but we're also seeing a greater impact with more forest fires across the whole nation.

For many migratory songbirds, they spend their breeding season in northern Canada, so making that long trek southbound to their wintering grounds is going to be huge if they're going to have to be migrating through wildfire smoke. This is going to impede their ability to maintain oxygen movement to their flight muscles. And we're talking about birds that are flying multiple distances, but some flying for multiple days at a time as well. 

Are you seeing declines in bird populations? 

Generally, bird populations are declining, and what's recently been shown in the last few fall migrations is that there's been mass die-offs throughout the United States when a lot of songbird populations that are migrating through. It's thought that forest fires are causing these die-offs to occur.

Your research looks at their breathing patterns. What did you uncover? 

I was interested in understanding how birds maintain oxygen movement in their flight muscles. What I found is that a lot of the birds that we see during migration have seasonally changed to support migration. They're breathing differently. They're taking slower or deeper breaths that bring in more oxygen. Their blood is able to bind oxygen better to move it to the tissues, and the flight muscles themselves have also changed to better use that oxygen to perform flight.

LISTEN | How migratory birds adjust to climate change:

You talk about forest fire smoke. Is there a certain altitude they can get to where they're breathing pure air?

Recent research has shown that many birds will actually fly high at 4,000 or 5,000 metres above sea level during their migratory flights. But we don't know if this is high enough for them to escape smoke plumes.

What types of birds did the study look into?

I was focusing on warblers, the tiny little birds that you would see in your backyard. I was looking at thrushes which are in the same family as robins. And then I was also looking at vireos which are in the crow family but are much smaller. They all respond differently to maintain oxygen uptake.

Some of them are more likely to change their breathing pattern, while others are more likely to change their blood's ability to bind oxygen and their tissues. This is really cool because it shows that not all species are going to respond the same way to changes in oxygen availability to maintain their flight performance, which means that some may be differentially impacted by forest fires.

What does this research signal for other kinds of birds?

I think the study is really exciting because it gives us a really good foundation for understanding what changes are important for bird migration. I think overall, really what it's reminding us is that for some birds that are going to do these really long-distance migrations, climate change is really going to impact them, especially if they have to go really far. This means that a lot of our birds are going to be impacted, especially those that potentially have to go even farther to get to their wintering destination.