Studies into the social and acoustic behavior of humpback whales to assist in the SETI mission

Passive acoustic recordings will be used to examine humpback whale non-song vocalizations (“social sounds”). Humpback whales produce many non-song vocalizations that have been structurally well documented (Payne and McVay 1971, Cerchio and Dahlheim 2001, Dunlop et al. 2007, Fournet et al. 2015). While it is presumed that these calls have a communicative function (Dunlop et al. 2008, Dunlop et al. 2010), little is known about their meaning and information content (Edds-Walton 1997, Tyack 2009, Dunlop et al. 2013). This study will record non-song vocalizations, together with observations of foraging behaviors and social interaction, and under a variety of environmental conditions to further characterize the diversity of non-song vocalizations and infer their function. As well, acoustic recordings will be used to test hypotheses concerning the production and function of feeding calls produced by humpbacks during cooperative feeding events. Playbacks will be used to further examine the function of HBW vocalizations by testing whether certain recorded vocalizations (e.g., non-song vocalizations, feeding calls, song phrases) elicit a behavioral response (approach, avoid, join, depart, etc.) in targeted whales. Insight into vocal meaning, gained through controlled playback experiments, can assist with stranding operations (Deeke 2006) as exemplified by playbacks of Alaskan feeding calls to lure a wayward humpback out of the Sacramento River (Baker 1985). Furthermore, these experiments can identify “positive controls” – sounds that elicit a predictable vocal response – that can be employed in advance of seismic exploration, tactical sonar, and other industrial activities to maximize whale detectability (Gibbs & Melvin 1993, SERDP 2009).