title: Evidence for simultaneous sound production in the bowhead whale (Balaena mysticetus).
abstract: Simultaneous production of two harmonically independent sounds, the two-voice phenomenon, is a well-known feature in bird song. Some toothed whales can click and whistle simultaneously, and a few studies have also reported simultaneous sound production by baleen whales. The mechanism for sound production in toothed whales has been largely uncovered within the last three decades, whereas mechanism for sound production in baleen whales remains poorly understood. This study provides three lines of evidence from recordings made in 2008 and 2009 in Disko Bay, Western Greenland, strongly indicating that bowhead whales are capable of simultaneous dual frequency sound production. This capability may function to enable more complex singing in an acoustically mediated reproductive advertisement display, as has been suggested for songbirds, and/or have significance in individual recognition.
authors.affiliation: Arctic Station, University of Copenhagen, P.O. Box 504, 3953 Qeqertarsuaq, Greenland. ote@science.ku.dk
authors.forename: Outi M
authors.initials: OM
authors.lastname: Tervo
authors.forename: Mads Fage
authors.initials: MF
authors.lastname: Christoffersen
authors.forename: Susan E
authors.initials: SE
authors.lastname: Parks
authors.forename: Reinhardt Møbjerg
authors.initials: RM
authors.lastname: Kristensen
authors.forename: Peter Teglberg
authors.initials: PT
authors.lastname: Madsen
mesh_terms: D000818:Animals; D050642:Bowhead Whale / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013997:Time Factors; D014828:Vocalization, Animal