In our latest post, author Caroline Isaksson explores the impacts of urban pollutants on songbirds! In their recent paper: “Effects of short-term multi-pollutant exposure on the oxidative stress status of captive songbirds”, Caroline investigates how three urban pollutants impacts Zebra finches physiologically. Caroline also shares the surprising results that will promote deeper research into this dynamic. Amid her experiments, Caroline imparts advice we all need to hear from time to time: “you are fine as you are and clever enough.”
🐦⬛ About the Paper
In the urban environment all wildlife, including humans, are exposed to a cocktail of pollutants on a daily basis. Our study experimentally investigates how three common urban pollutants:soot, artificial light at night (ALAN) and traffic noise, affect oxidative stress responses during single or combined exposure using the zebra finch as our model system. The overall aim of the paper was to understand the impact that urbanization and its associated stressors and habitat changes has on urban-dwelling birds. In this paper, we show that simultaneous short-term exposure to artificial light at night and traffic noise improved their oxidative stress balance by increasing the antioxidant responses and reducing oxidative damage.
The impact of these results is that combined exposure of pollutants to Zebra finches could give profoundly different responses to single exposures. This is because the physiological effects are not always that “one plus one equals two”, but it could instead equal to three or minus one. The disentanglement of these single and combined exposures is a key for understanding the broader impact of urbanization.
🧠 About the Research
As an ecophysiologist, I seek to understand how the physiological responses can improve or damage the body in different environmental conditions. Here we have done a controlled exposure experiment, but since we want to relate it to our studies of wild urban birds, we want to use non-lethal tissues i.e., blood (it’s non-lethal because it doesn’t require euthanizing the animal to extract the tissue). Thus, our target sampling was to take blood samples prior to and after a 5-day exposure to the pollutant(s). The experiment was very logistically challenging and demanding, with 8 experimental groups, including new birds every week and with a new exposure that needed to be monitored over a period of 5 days. But with a good team of researchers from both biology and physics, we managed!
When it came to the results, we were initially very surprised that the combined exposure to ALAN and traffic noise improved the birds’ physiological state. We were also surprised that there were no effects on the antioxidant response to soot exposure. Since we were surprised about the results regarding soot, we wanted to explore this more deeply. This requires digging deeper by first asking the question “Could timing of the sampling, the tissue sampled, the biomarkers assessed, or the soot type/concentration influence the results?”. Through this question, we are continuing the research to better understand this scenario.
👋 About the author
I’ve been interested in ornithology and environmental questions since I was a little girl, so it was an easy choice for me to study biology, and with urban ecology you can nicely combine current environmental issues as it relates to urbanization and development with avian ecology. I’m now a professor at the Department of Biology in Lund. From my years of research, I’m currently writing a book chapter on avian coloration in the Anthropocene so my research time is now focused on reading up on this topic – kind of like an old friend that came back to visit and catch up. In my spare time however, I enjoy family time, hanging out in the garden or in a nice nature reserve or cheering on the kids either during a soccer game or during horse riding. I love cooking (but hate baking) and my secret love is to sing karaoke (so songbirds are a fitting group to study!).
As it relates to my professional development, I’ve been fortunate to have a straight line in my career path. Of course, there is always some grants that fail, but luckily others are a success. The aim for gender equality across all boards, committees, talks etc. can be somewhat overwhelming as a woman in science. And I think all women (and other underrepresented groups) should be careful not get involved in everything, because ultimately, there will be less time for research, which is not cool or fair either! Overall, I would say to myself – you are fine as you are and clever enough, the key to success is your passion to your topic and hard work – do what you love, and it will be fine!
Like the blog post? Read the research article here.
