Acoustic Mitigation Devices (AMDs) to Deter Marine Mammals from Pile Driving Areas at Sea: Audibility & Behavioural Response of a Harbour Porpoise & Harbour Seals

the first goal of the two audibility studies was to determine the hearing thresholds of harbour porpoises and harbour seals for the sounds produced by three commercially available AMDs (one of which produces three different sounds). The second and third goals, which were extra to the original proposal, were to compare the hearing thresholds for the AMD sounds with the tonal thresholds (to determine whether hearing thresholds of broadband signals can be predicted from hearing thresholds for tonal sounds), and to estimate the distances at which the sounds made by the three AMDs can be heard by porpoises and seals at sea.