Beluga whale (Delphinapterus leucas) vocalizations and call classification from the eastern Beaufort Sea population

• Published in: The Journal of the Acoustical Society of America
• Main Authors: Garland, Ellen Clare, Castellote, Manuel, Berchok, Catherine
• Other Authors: University of St Andrews.School of Biology, University of St Andrews.Sea Mammal Research Unit, University of St Andrews.Centre for Social Learning & Cognitive Evolution, University of St Andrews.Centre for Biological Diversity
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2015
• Subjects: QH301 Biology; GC Oceanography; NDAS; QH301; GC; Beaufort Sea; Beluga; Beluga whale; Beluga*; Delphinapterus leucas; Alaska
• Online Access: https://hdl.handle.net/10023/7874; https://doi.org/10.1121/1.4919338

Funding was provided by the Bureau of Ocean Energy Management under InterAgency Agreement M09PG00016. E.C.G. was supported by a National Research Council (National Academy of Sciences) Postdoctoral Fellowship. Beluga whales, Delphinapterus leucas, have a graded call system; call types exist on a continuum making classification challenging. A description of vocalizations from the eastern Beaufort Sea beluga population during its spring migration are presented here, using both a non-parametric clas- sification tree analysis (CART), and a Random Forest analysis. Twelve frequency and duration measurements were made on 1019 calls recorded over 14 days off Icy Cape, Alaska, resulting in 34 identifiable call types with 83% agreement in classification for both CART and Random Forest analyses. This high level of agreement in classification, with an initial subjective classification of calls into 36 categories, demonstrates that the methods applied here provide a quantitative analysis of a graded call dataset. Further, as calls cannot be attributed to individuals using single sensor pas- sive acoustic monitoring efforts, these methods provide a comprehensive analysis of data where the influence of pseudo-replication of calls from individuals is unknown. This study is the first to describe the vocal repertoire of a beluga population using a robust and repeatable methodology. A baseline eastern Beaufort Sea beluga population repertoire is presented here, against which the call repertoire of other seasonally sympatric Alaskan beluga populations can be compared. Peer reviewed