Setting up above ground boom-boxes mounted in camouflaged boxes powered by car batteries and programmed for four months to broadcast predator sounds according to a schedule that simulated when and how predators would normally call.
Such broadcasting was to create the perception for forest birds that there was increased abundance of predators in the forest, The curiosity was in knowing whether forest birds that are prey to these predators would use such cues and respond by altering their decision about where to breed.
The study looked at three types of predators and compared how their cues affected forest birds. It turned out that forest birds recognized vocal cues of the Eastern screech-owl, blue jay or Cooper’s hawk as indications of different threats: While different predator cues altered bird community make-up, their effects were distinctive.
While some bird species clearly avoided plots with feared predators, other species seemed to alter their behavior to make themselves less conspicuous.
Results from this study established that animals are using acoustic cues to make important survival decisions. Species actually listen to each other and predators’ calls to detect whether a predator is lurking nearby.
The fear-based behaviors of birds the “soundscape ecology” is focused on understanding how animals rely on natural sounds. We can’t just protect natural habitat for wildlife, we have to protect natural soundscapes, too, which is difficult for us noisy humans with all of our planes and trucks and oil rigs and fracking machines.