In the wild, birds don’t have a nice and peaceful oasis like one might think. Their habitats are riddled with noise from human interaction, and sometimes, that noise doesn’t come from interaction at all, but rather from the surrounding noises that result from our actions.
As humans become louder in our way of life, birds are finding it increasingly difficult to communicate with one another and are having to increase their volume just to hear one another. The news comes from a study just published in the journal Bioacoustics, where researchers studied birdsongs in Washington D.C.
Image Credit: Sweetaholic/Pixabay
One of the things that can impose on birds hearing the calls of other birds is traffic noise from cars. The loud noise of oncoming and ongoing cars on roads that are close to bird nests in surrounding trees can easily muffle out birdsongs and communication, which can make finding one another and communicating danger more difficult. This has implications for their survival and potential negative side-effects.
It certainly adds to the problem that people enjoy modifying their cars; while they roll off the factory assembly line with quiet exhaust systems and tires with as little road noise as possible, car owners often change to louder exhaust systems and put bigger, knobbier tires on their trucks that produce more road noise.
As cars get louder, and new roads are paved through the middle of forests, birds find it harder to stay away from manmade noise. Their only other option is to chirp even louder, which as you can probably imagine, strains their vocal systems and probably annoys them.
Imagine being around a deaf person every single day, and when you try to speak to them, they always reply with, “what?” – If you already deal with this, then you already know how annoying it is to have to repeat yourself. Well, it turns out birds have to deal with this every single day.
As the researchers were recording the noise, they noticed that instead of emitting birdsongs of varying frequencies, which often attract mates and help other birds to hear and notice the sounds, birds were emitting birdsongs of a single static frequency and louder, shorter bursts. They also noticed that surrounding birds were less likely to respond.
They also noted how when traffic noise temporarily disappeared, birds would temporarily return to their typical birdsong habits, which makes sense, because you wouldn’t keep shouting over loud noise if there wasn’t any more noise to begin with.
It suggests that birds are aware of the sound environment around them and can compensate for loud noises that drown their birdsongs out, but we shouldn’t rule out how birdsongs negatively impact bird lives – since birds aren’t as attracted to loud and obnoxious calls, this reduces mating and interaction, which in theory, could someday reduce populations.
"The results confirm that temporary measures to reduce traffic noise, such as weekend road closures, can benefit animals and is a feasible and effective option for managing traffic noise," study lead author Katherine Gentry said.
Unfortunately, there really aren’t any significant “fixes” we can make to improve the situation for birds. This is an annoyance they would have to live with.
Source: Science Daily