Study
Singing in a silent spring: Birds respond to a half-century soundscape reversion during the COVID-19 shutdown
Derryberry, Elizabeth P.; Phillips, Jennifer N.; Derryberry, Graham E.; Blum, Michael J.; Luther, David
Science, 2020
White-crowned sparrow song was recorded at urban and rural sites around San Francisco during the 2020 traffic shutdown and compared with recordings from the same sites in previous years, alongside measurements of the change in background noise.
- Studied in
- Zonotrichia leucophrys
- Sample size
- white-crowned sparrows recorded in and around San Francisco before and during the shutdown
Background noise in the city fell to levels last typical of the 1950s. Birds sang more quietly, and the bandwidth and low-frequency content of their songs increased, with modelling indicating a substantial increase in the distance over which song would carry.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Urban song features are flexible and track the noise environment closely, reverting within weeks when the noise is removed.
How NatureHQ reads it
An accidental experiment that no ethics committee could have approved, and the strongest evidence that the urban song differences are plastic adjustments by individual birds rather than a sorted population. The direction matters too: with the noise gone the birds got quieter and their songs got *wider*, which fits the amplitude explanation rather than the escape-the-masking one. It is still observational, and comparing a year with previous years leaves the rest of 2020 in the comparison.
- A natural experiment: the shutdown changed pedestrian traffic, disturbance and human presence as well as noise.
- One species, one metropolitan area, one season.
- The gain in communication distance is a modelled consequence, not a measured one.
Listening to a city with the traffic switched off
Do city birds sing differently because they adjust to noise, or because different birds live in cities?
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Birdsong in cities
City birds really do sing at a higher pitch, and the best explanation is not that they are dodging traffic noise — it is that they are singing louder, and louder is higher.
Birdsong in cities
When the traffic stopped in 2020, city birds changed their songs within weeks — so the urban pattern is birds adjusting, not different birds living in cities.
Published by: American Association for the Advancement of SciencePublished in Science or Science Advances (AAAS).
doi.org/10.1126/science.abd5777
Checked against Crossref and OpenAlex on 2026-09-28, and they agree on the title, the authors and the year.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-09-02.