Biodiversity impacts of ship movement, noise, grounding and anchoring

Abstract

Marine life in the Mediterranean Sea is threatened by intensive human activities such as fisheries, ship traffic, pollution and coastal development. Cetaceans and other vertebrates are affected not only by chemical pollution, but also by noise pollution (Richardson et al., 1995; Simmonds et al., 2004). Noise has become a ubiquitous form of marine pollution, especially in areas of heavy maritime traffic and along developed coasts. Intense underwater noise is generated by airguns, widely used for geophysical exploration in the oil and gas industry as well as for academic and government research purposes; by high power sonar, either military or civilian; by ship traffic; by shoreline and offshore construction works; and by a number of other commercial, scientific, military and industrial sources. The most powerful noises (from airguns, sonars, and explosions) may directly injure animals in the vicinity of the source. General ship traffic, heavy industries on the coast and a variety of other human activities generally do not generate such intense noise, but the acoustic pollution they produce is constant over time and may affect large areas. It may be a serious hazard not only to individual animals, but also to entire populations. Such increased background noise affects underwater life just as airborne noise affects terrestrial animals, including human beings.