[ad_1]
Of: TT
Published:
Updated:
Photo: Wolfgang Wander / CC BY-SA
White-crowned sparrows quickly regain their voluminous song when traffic noise ceases, a new study shows. Stock Photography.
As traffic declined during pandemic closures, city birds began to sing with more nuance, according to a new study.
– Even though they have been exposed to noise for several decades, they quickly find their way back to their previous song. It’s comforting, says ecologist Jan Olof Helldin.
In noisy urban environments, many birds are forced to sing simpler, with fewer nuances and louder tones and with more beeps that penetrate low-frequency traffic noise. By the way, the same phenomenon has been observed in us humans and is called the Lombard effect. As background noise increases, we unknowingly begin to speak in a brighter voice and emphasize syllables aloud more carefully, and it takes a voluntary effort to lower our voice.
An interesting question in the research world is how permanent are these behavioral changes among animals that are forced to adapt to various forms of environmental disturbances for a long time. For example, does the original bird song remain even though birds have been forced to sing a simplified version of the species’ trudel lute for several generations?
Wider tonal range
A new American study shows that at least the white-crowned sparrow in several San Francisco Bay cities can immediately revert to a more original song when the traffic noise stops. During the corona pandemic stops, the sparrows began to sing with lower volume, more drills and a greater range of tones.
“A greater frequency range means more information transmission and better song quality,” the researchers write in their study published in the journal Science.
– The unique thing about this study is that the researchers had studied the song of these birds before, both in urban areas and in the field. So now it became a large-scale experiment when traffic noise suddenly subsided and it could be seen that bird behavior changed rapidly, says Jan Olof Helldin, an ecologist and researcher at the Center for Biological Diversity at the Swedish University of Agricultural science.
Poorer reproduction
TT: Is there a downside to birds adapting their song to noise?
– Yes, other studies have seen that it can impair reproductive success, because it becomes more expensive for birds to make themselves heard and assert territory, says Jan Olof Helldin.
According to American researchers, the noise level in the observed cities decreased so much that it resembled the level of the 1950s. “The restrictions effectively erased half a century of increasing noise pollution,” the researchers write in their study.
– Perhaps one should be a little careful not to make too big changes in this study of a single species in one area. But it is still gratifying to see how nature can quickly find its way back when the disturbances subside. This is important knowledge, says Jan Olof Helldin.
Published:
