Since Corona, Birds Sing More Beautifully
During the Corona lockdown, white-crowned sparrows in San Francisco sang more quietly and melodiously. The birds took advantage of the sudden quiet to perform at their very best.
While public life in San Francisco came largely to a standstill due to the Corona pandemic, white-crowned sparrows discovered unexpected vocal abilities in the sudden quiet. According to researchers, they performed at their absolute best.
The male specimens of the white-crowned sparrow (Zonotrichia leucophrys), widespread across the USA and Canada, suddenly sang more softly, improved the range of their voices, and thereby became more attractive to females, according to a study published on 1 October 2020 in the journal «Science».
««When the city was loud, they really called out loud», said lead author Elizabeth Derryberry of the University of Tennessee. When sweeping lockdown restrictions were imposed in California in spring and traffic dropped significantly, noise levels in San Francisco fell by around 50%, dropping to levels last seen in 1954.
The researchers compared recordings of white-crowned sparrow calls from the previous year with recordings made at the same locations in April and May 2020, and found that the birds were now singing noticeably more quietly and hitting lower notes.
Derryberry compared the bird calls to human behaviour at parties: while you can still talk quite normally at the beginning of the evening, you have to speak louder and louder as more guests arrive. «If you’re shouting at a cocktail reception, your voice is hardly at its best», said the researcher. The same applies when white-crowned sparrows have to compete against urban noise.
Lockdown Improves Love Life
As noise decreased during the Corona restrictions, the males suddenly sounded much «better and sexier»: «To females, they sounded like better partners.» Although they were now calling more quietly, they could also be heard across a range twice as large as before in the quieter city.
According to the researchers, the findings of the study show how quickly birds can adapt to changing conditions. Long-term solutions to combat noise could have positive effects, such as greater biodiversity.
