Evidence for the functions of surface‐active behaviors in humpback whales (Megaptera novaeangliae)

Abstract

As part of their social sound repertoire, migrating humpback whales (Megaptera novaeangliae) perform a large variety of surface‐active behaviors, such as breaching and repetitive slapping of the pectoral fins and tail flukes; however, little is known about what factors influence these behaviors and what their functions might be. We investigated the potential functions of surface‐active behaviors in humpback whale groups by examining the social and environmental contexts in which they occurred. Focal observations on 94 different groups of whales were collected in conjunction with continuous acoustic monitoring, and data on the social and environmental context of each group. We propose that breaching may play a role in communication between distant groups as the probability of observing this behavior decreased significantly when the nearest whale group was within 4,000 m compared to beyond 4,000 m. Involvement in group interactions, such as the splitting of a group or a group joining with other whales, was an important factor in predicting the occurrence of pectoral, fluke, and peduncle slapping, and we suggest that they play a role in close‐range or within‐group communication. This study highlights the potentially important and diverse roles of surface‐active behaviors in the communication of migrating humpback whales.

The behavioural response of migrating humpback whales to a full seismic airgun array

“…First a 'base' model was generated for each response variable which incorporated significant ( p , 0.05) social and environmental predictor variables [40,41]. This 'base' model included all data from baseline (n ¼ 85), control (n ¼ 33) and active (n ¼ 34) groups.…”

Humpback whales Megaptera novaeangliae alter calling behavior in response to natural sounds and vessel noise

“…Humpback whales are a migratory baleen whale species with a cosmopolitan distribution and a diverse acoustic repertoire that includes song (Payne & McVay 1971, Herman 2017, calls (Tyack 1983, Silber 1986, Thompson 1986, Stimpert et al 2011, and percussive sounds (breaches, flipper slaps, tail lobs; Whitehead 1985, Dunlop et al 2010, Kavanagh et al 2017. While the exact function of these sounds is not certain, humpback whales use acoustic communication in concert with vital life functions such as breeding (Herman 2017), foraging (D' Vincent et al 1985, Thompson 1986, Stimpert et al 2007), migrating (Dunlop et al 2007), socializing (Silber 1986, Dunlop et al 2008, Dunlop 2017, and across age and sex classes (Zoidis et al 2008, Silber 1986, Dunlop et al 2008, indicating that acoustic communication is an important aspect of behavior for this species.…”

Humpback Whale Movements and Behavior in Response to Whale-Watching Vessels in Juneau, AK

“…Transitions from vocal communication to non-vocal surface-generated communication (i.e., breaching, tail-slapping) by humpback whales have also been detected in noisy environments (i.e., increased background noise, high wind speeds) (Dunlop et al, 2010). However, surface active behavior has also been attributed to communication to distant groups (Kavanagh et al, 2017). This indicates that cessation of surface active behavior could result from acoustic masking due to vessel noise and subsequent inability to communicate (Richardson et al, 1995;Gabriele et al, 2018).…”