15: Beaked Whale Group Deep Dive Behavior from Passive Acoustic Monitoring

Although the causal link between sonar and stranding has not been described explicitly, beaked whales are one of the cetacean taxa more sensitive to use of Navy sonar (Moretti et al., 2014; Tyack et al., 2011). Despite their vulnerability, Blainville's beaked whale, Mesoplodon densirostris (Md), are routinely detected year-round on the AUTEC range, coincident with routine use of Navy sonar. This has led to the suggestion that perhaps whales can become habituated to sonar or at least do not respond in the same way as naïve animals (Schorr et al., 2014). Perhaps whales choose to stay in areas of frequent sonar use because the advantages of greater foraging opportunities outperform the disadvantages of sonar exposure. This suggestion makes AUTEC an excellent laboratory to understand not only fundamental aspects of their biology and ecology, but also how and why these whales might be impacted by the use of sonar.