Underwater noise - a man-made problem
Whales and seals depend on their sense of hearing for survival. Man-made underwater sounds can impair their hearing in both the short and long term, displace them from vital habitats, cause a change in important patterns of behaviour and thereby deteriorate the survival capacity of these marine mammals.
Most whales and seals, many fish and even some invertebrates such as squid rely on acoustic signals for a great number of basic activities, including communication, mate selection, location of prey, protection against predators, or navigation. A change in ambient noise can have a negative impact on the biological fitness of individual animals or even entire populations.
Read full article at the source: https://www.umweltbundesamt.de/en/underwater-noise#textpart-1