|Title||Context-dependent variability in blue whale acoustic behaviour|
|Publication Type||Journal Article|
|Year of Publication||2018|
|Authors||Lewis L.A, Calambokidis J, Stimpert A.K, Fahlbusch J., Friedlaender A.S, McKenna MF, Mesnick S.L, Oleson E.M, Southall B.L, Szesciorka A.R, Sirovic A.|
|Journal||Royal Society Open Science|
|Type of Article||Article|
|Keywords||acoustic communication; Balaenoptera musculus; balaenoptera-musculus; behavioural context; biologging science; blue whale; calling behavior; eastern tropical pacific; eubalaena-glacialis; humpback whales; inbreeding avoidance; megaptera-novaeangliae; northeast pacific; Science & Technology - Other Topics; Song; southern california bight|
Acoustic communication is an important aspect of reproductive, foraging and social behaviours for many marine species. Northeast Pacific blue whales (Balaenoptera musculus) produce three different call types-A, B and D calls. All may be produced as singular calls, but A and B calls also occur in phrases to form songs. To evaluate the behavioural context of singular call and phrase production in blue whales, the acoustic and dive profile data from tags deployed on individuals off southern California were assessed using generalized estimating equations. Only 22% of all deployments contained sounds attributed to the tagged animal. A larger proportion of tagged animals were female (47%) than male (13%), with 40% of unknown sex. Fifty per cent of tags deployed on males contained sounds attributed to the tagged whale, while only a few (5%) deployed on females did. Most calls were produced at shallow depths (less than 30 m). Repetitive phrasing (singing) and production of singular calls were most common during shallow, non-lunging dives, with the latter also common during surface behaviour. Higher sound production rates occurred during autumn than summer and they varied with time-of-day: singular call rates were higher at dawn and dusk, while phrase production rates were highest at dusk and night.