The categorisation of undersea noise as a source of pollution and as a potential threat to marine biodiversity began in the early 1990s in response to a coincidence of three ‘focusing events’:2 the shock testing of vessels by the US Navy; the transmission of up to 205 decibels of sound off Heard Island as part of the Acoustic Thermometry of Ocean Climate (ATOC) experiment; and the testing of low- and mid- frequency active sonar by US, Australian and NATO naval vessels. Somewhat less controversial, but arguably no less serious, is undersea noise resulting from seismic surveys, dredging and construction activities, shipping, offshore wind farms, sonar use associated with fishing and ocean science experiments. Recent scientific research indicates that sources of undersea noise such as military sonar can cause cetaceans and other marine mammals’ physiological damage.3 Moreover, recent instances of atypical mass strandings have been linked to the use of tactical mid-frequency active sonar.4 The presence of undersea noise may also result in the exclusion of cetaceans from important habitats or impede reproductive and feeding patterns.5 Finally, it should be noted that comparatively little research has been undertaken in connection with the impact of undersea noise on species other than cetaceans, such as fish and deep sea squid,6 and no such research has been carried out in respect of diving birds such as penguins and cormorants. The issue of noise pollution and in particular, its impact on cetaceans, has reached the attention and the agenda of a number of international organisations concerned with the protection of the marine environment and the protection of biodiversity. These organisations include the International Whaling Commission (IWC)7 and the 1979 Convention on Migratory Species.8 Both ASCOBANS 19929 and ACCOBAMS 199610 have adopted resolutions on undersea noise and cetaceans and in particular, have addressed noise resulting from seismic surveys and whale watching activities.11 More generally, the impact of undersea noise on marine life has been identified as an issue that would benefit from future attention of the General Assembly by the United Nations Open-Ended Informal Consultative Process on Oceans and the Law of the Sea (UNICPOLOS) in its fifth report published in 2004 and also in its sixth report published in 2005.12 As a consequence of this recommendation, the United Nations General Assembly in Resolution 60/30 (2005) declared that it “encourages further studies and consideration of the impacts of ocean noise of marine living resources.”13 The Committee on Environmental Protection has discussed undersea noise in the Southern Ocean at Antarctic Treaty Consultative Meetings since 200014 and the topic has benefited from examination by SCAR at workshops held in 2002, 2004 and 2006.