India, April 14 -- F
or most of us, in the pandemic, birdsong seemed to grow louder. But studies conducted since are revealing that, in some places, the opposite was true.
As traffic noises disappeared from San Francisco, for instance, the dramatic buzzes and trills of the white-crowned sparrow quieted - by as much as 30%. They no longer needed to shout. Instead, their songs became richer, more complex, as they warned each other of nearby predators, repelled competing rivals, or attracted mates.
Even small improvements to noise pollution can lead to the reversal of the environmental damage that man-made sound has caused, states the study, titled Singing in a Silent Spring, conducted by researchers in Tennessee and California and publishe...