Keeping the Noise Down: Approaches to the Mitigation and Regulation of Human-Caused Ocean Noise

Most marine animals, including marine mammals, fish, and invertebrates, use sound for almost all aspects of their life, including reproduction, feeding, predator and hazard avoidance, communication, and navigation. In the marine environment, vision is only useful over tens of meters, whereas sound can be heard for thousands of kilometers. The potential area impacted by even one noise source can extend to millions of square kilometers. Ocean background human-caused noise levels have doubled every decade for the last several decades in some areas, mainly from commercial shipping. So, how should a transboundary pollutant such as noise be regulated? Interestingly, the 1982 United Nations Convention on the Law of the Sea includes the word ‘energy’ to define ‘pollution of the marine environment’, as in “the introduction by man ... of substances or energy into the marine environment ... which ... is likely to result in ... harm to living resources....”1 Energy in this context can include both thermal and acoustic or noise pollution.2 Thus, the United Nations General Assembly (unga) in paragraph 107 of its resolution 61/222 on ‘Oceans and the law of the sea’, adopted on 20 December 2006: “Encourages further studies and consideration of the impacts of ocean noise on marine living resources....”3 Further, unga resolution 70/235 adopted on 23 December 2015