| Summary: | In recent decades, anthropogenic noise has become recognised as a major pollutant worldwide and the study of its impacts has increased due to the potential for adverse consequences on wildlife. For marine environments, where sound is transmitted very efficiently through water, underwater noise has increased, mainly, at low and medium frequencies. Of all marine organisms, cetaceans may be the most affected, as they depend primarily on sound to communicate, navigate and find food. Accordingly, the general aims of this thesis are to identify the types of anthropogenic noise facing New Zealand’s cetaceans, the potential impacts, review current legislation, and to propose improvements to enhance current mitigation measures of impacts. My systematic review showed that 90% of the information about impacts of noise pollution on cetacean comes from peer-review journals and, although available from 1975, studies of marine noise pollution substantially increased after 1997. In addition, I identified the limited information on this topic in important areas such as Latin America, Africa and Southeast Asia, as well as regions in the Arctic and Southern Ocean. I also found that most effort has been focused on the impact of vessels, and bottlenose dolphin and harbour porpoise are, by far, the most studied species, showing a disparity in research coverage of both sources of noise and species. For New Zealand, there is a striking lack of knowledge of the range of sources of noise on cetaceans (excluding vessels). The information I compiled on New Zealand’s cetacean distributions showed that three main groups are well represented: baleen whales, delphinids and beaked whales. Nonetheless, the information available for these species varies greatly. While there are some species very well studied, for others New Zealand species, the available information is scarce, as in the case of beaked whale. Current mitigation measures can only be effective if comprehensive data are used to inform them. For example, planning surveys at different ...
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