Noise affects the behaviour of animals
The hearing of animals has been adapted to the natural sounds of their environment over time to distinguish relevant from irrelevant sounds. But human-induced noise has greatly increased over the last decades and affects many animals. Particularly affected are animals living in the sea, which are having communication problems due to noise from drillings platforms, ships and seismic surveys.
The call of whales
Studies have revealed that right whales and North Atlantic right whales had more powerful calls in noisy environments. Blue whales on the other hand had more frequent calls during noisy seismic surveys. Researchers found that the calls of whales were in order to maintain social contact which indicates a change in their behaviour.
Furthermore, researchers have diagnosed a hearing loss in dolphins which is possibly due to human-induced noise. This type of hearing loss was found in half of the stranded dolphins in America.
The birds singing
Even in birds, the researchers found a correlation between their singing and human-induced noise, although a hearing loss could not be detected.
In robins for example, it was observed that they preferred to sing during the night in areas with lots of noise during the day. Other species changed their singing behaviour in noisy environments.
Noise distracts attention
In an experiment with chaffinches, researchers found that noise distracts them from foraging because they constantly had to keep an eye out for enemies. From this the researchers conclude that it is more difficult for chaffinches to find enough food in noisy environments.
Source: videnskab.dk