The power of birdsong to lift the human spirit has long been appreciated.
In Shakespeare’s Sonnet 29, a suffering person is revived when “Haply I think on thee, and then my state,/Like to the lark at break of day arising/From sullen earth sings hymns at heaven’s gate ….”
Today, the effect is evident in apps designed to soothe people with birdsong, and in a growing body of research showing that when people hear recordings of birds singing they cope better with stress and feel more restored.
But what happens when we hear those birds amid the clamor of urban life? After all, most of us can’t easily get away to a peaceful forest far from the nearest road.
Even relatively quiet traffic sounds well below thresholds recommended by the World Health Organization (WHO) take a toll, leaching away the bird-born calm, according to a new paper in the journal People and Nature.
Although we are creatures of the Anthropocene, apparently a part of our ancient brains that reacts to sounds didn’t get the memo.
“Traffic noise undoubtedly affects the psychological benefits of natural soundscapes. With urban planning now including more green spaces, it is important that steps are taken so that people enjoy such areas to their fullest,” said Eleanor Ratcliffe, a University of Surrey researcher who studies interactions between psychology and the environment.
Ratcliffe and colleagues at several United Kingdom universities conducted experiments to understand how urban noise affected the benefits of hearing birds singing. First, they conducted on online experiment in which more than 1,500 people listened to a series of 9 audio recordings. Each contained songs from three different species totaling five birds, many of them mixed with sounds of a city, such as traffic noise. The recordings varied by the loudness of the human sounds and the complexity and loudness of the bird recordings.
Afterwards, people answered questions about their responses, such as, “The variety of sounds in this recording make me feel ….”
For a deeper dive in more controlled conditions, the researchers conducted similar experiments with 62 university students in a lab. There they also hooked the subjects up to a device that measured the variability in their heart rate from beat to beat. A more variable rate is associated with lower stress.
The results showed that traffic noises consistently eroded the benefits of the birds. Louder traffic, not surprisingly, had a bigger effect. But even traffic perceived at 43 decibels – roughly equivalent to a refrigerator’s hum or a quiet office – diminished the benefits. The rankings by the study participants were mirrored in their heart rate variability. When traffic mixed with the birds, the variability was lower.
There’s evidence that at least part of what’s going on is that the overall intensity of sounds can overload people. The negative effects of loud traffic were amplified when the nature sounds were also dialed up to greater intensity.
In some ways, it appears that humans prefer a sort of acoustic middle ground. When the natural sounds were at a mid-level of loudness and complexity, people generally reported feeling better than when natural sounds were high end or low end and mixed with city noise. Likewise, people perceived more bird diversity in that mid-range, even though the number and species of birds were the same in each recording.
The findings suggest that when organizations are designing urban refuges such as parks, they shouldn’t forget to shut their eyes and listen. Measures such as lower speed limits on nearby roads or thicker perimeter vegetation could help preserve the acoustic benefits of the sweet sounds of Shakespeare’s lark.
“It is important that people get to spend time in nature and are able to appreciate its benefits without being distracted by noise,” said Ratcliffe.
Uebel, et. al. “The influence of acoustic characteristics and anthropogenic noise on restorative perceptions of natural soundscapes.” People and Nature. Aug. 25, 2026.
Photo by Mateusz Walendzik/Pexels
