Marine sound, natural or anthropogenic, has long fascinated scientists, mariners, and the general public. The haunting songs of humpback whales and the pings of antisubmarine sonar, among other sounds from the oceans, convey allure and suspense.
Recently, that suspense has moved from television screens to courtrooms, where navies, scientists, and environmentalists have clashed over the effects of anthropogenic sound on marine mammals [Malakoff, 2002]. Triggered by atypical mass strandings of primarily beaked whales in concordance with naval sonar exercises off Greece in 1996 and the Bahamas in 2000, substantial efforts to obtain baseline data to understand the possible effects of anthropogenic sound on marine mammals have commenced. Recent advances include dive and vocalization records of beaked whales [Johnson et al., 2004] and detailed observations of the behavioral response of sperm whales on seismic signals [Jochens et al., 2006].