Underwater acoustic behavior of bearded seals ( Erignathus barbatus ) in the northeastern Chukchi Sea, 2007–2010

• Published in: Marine Mammal Science
• Main Authors: Frouin‐Mouy, Heloise, Mouy, Xavier, Martin, Bruce, Hannay, David
• Other Authors: Shell Exploration & Production Company, ConocoPhillips Company, Statoil USA E&P, Inc
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2015
• Subjects: Aquatic Science; Ecology, Evolution, Behavior and Systematics; Chukchi Sea; bearded seal; Chukchi; Erignathus barbatus
• Online Access: http://dx.doi.org/10.1111/mms.12246; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fmms.12246; https://onlinelibrary.wiley.com/doi/pdf/10.1111/mms.12246; https://onlinelibrary.wiley.com/doi/full-xml/10.1111/mms.12246

Abstract Bearded seal ( Erignathus barbatus ) calls were recorded using autonomous passive acoustic recorders deployed in the northeastern Chukchi Sea between October 2007 and October 2010. Continuous acoustic data were acquired during summer (August to mid‐October), and overwinter data (mid‐October through July) were acquired on a duty cycle of 40/48 min every 4 h. We investigated the spatio‐temporal distribution and acoustic behavior of vocalizing bearded seals in this multiyear data set. Peaks in calling occurred in spring, coinciding with the mating period, and calls stopped abruptly in late June/early July. Fewer calls were detected in summer, and the vocal presence of seals increased with the formation of pack ice in winter. Vocal activity was higher at night than during the day, with a peak around 0400 ( AKST ). Monthly patterns in proportional use of each call type and call duration were examined for the first time. The proportion and duration of AL 1(T) and AL 2(T) call types increased during the mating period, suggesting that males advertise their breeding condition by producing those specific longer trills. The observed seasonal and diel trends were consistent between years. These results improve our understanding of occurrence and acoustic behavior of bearded seals across the northeastern Chukchi Sea.