Traffic noise in cities means that birds sing more loudly than they would normally and with less variety in their song. Prof Derryberry from the University Of Tennessee said in the journal Science that the behavior is similar to that of people at a cocktail party. If there is a lot of background noise people speak more loudly but their conversations are restricted to basic chitchat. They cannot get into an in-depth philosophical conversation because the background noise just drowns it out and nuances are difficult to communicate. It is the same for birds and bird song. She studied the behavior of white-crowned sparrows.
- Birds sing jazz for pleasure
- Songbirds need to warm up, like an opera singer, before their dawn chorus
Although birds vary the volume of their song dependent upon background noise it was found that during the lockdown background noise had decreased by seven dB but the volume of birdsong decreased by four dB. In other words the birds still had a raised volume. It did not decrease by the same amount that the background noise decreased.
The Times journalist, Tom Whipple, provided us with a nice thought in his article of 25 Sept. 2020. John Keats alluded to the fact in his poem Ode to a Nightingale that people in the past would have heard the same birdsong as we do today. Tom Whipple says that this is no longer true because today, in cities, birds are singing more loudly and their birdsong is less interesting.