There is increasing concern about the harmful effects of man-made noise (anthropogenic) on the marine environment and species within. While anthropogenic noise is not the only noise source in the marine environment, its level is increasing due to growth in commercial shipping, military activities geophysical surveys and inshore works.
Anthropogenic noise may be considered an acoustic pollutant, and comes from a variety of sources such as; seismic surveys, ship sonar, ship traffic, oceanographic experiments, drilling and other marine works etc. Cetaceans rely primarily on sound for many critical natural functions such as; to communicate, locate and capture prey, navigate their environment, and avoid obstacles and predators. Therefore, they are sensitive to noise exposure and it can have a range of effects upon them varying in severity depending on the level of noise exposure.