Underwater shipping noise impacts to marine life: a global issue

Underwater noise from shipping and its impact on marine life has been addressed by numerous governments and non-governmental organizations since the early part of the twenty-first century. The issue has reached the highest level of shipping regulation, the International Marine Organization or IMO, a sub-organization to the United Nations. Since the 1990's, marine biologists have known that the increase in underwater-radiated noise has multiple negative impacts on various species of marine life and each species has different impacts with different acoustic thresholds. At regulatory levels, it is believed that the problem can be solved by reducing underwater radiated noise from all vessels; shipping noise. However, there is no simple solution. It requires a cross-functional team including marine-biologists, underwater acousticians, vessel owners/operators, and naval architects/ship designers. Solutions will only occur with efforts directed at the highest governmental and inter-governmental levels. Topics that are being addressed include impacts on marine life, underwater noise limits, operational restrictions on shipping, shipboard noise mitigation, and methods of underwater sound prediction and measurement.