title: Single-lobed frequency-dependent beam shape in an echolocating false killer whale (Pseudorca crassidens).
abstract: Recent studies indicate some odontocetes may produce echolocation beams with a dual-lobed vertical structure. The shape of the odontocete echolocation beam was further investigated in a false killer whale performing an echolocation discrimination task. Clicks were recorded with an array of 16 hydrophones and frequency-dependent amplitude plots were constructed to assess beam shape. The majority of the echolocation clicks were single-lobed in structure with most energy located between 20 and 80 kHz. These data indicate the false killer whale does not produce a dual-lobed structure, as has been shown in bottlenose dolphins, which may be a function of lowered frequencies in the emitted signal due to hearing loss.
authors.affiliation: Hawaii Institute of Marine Biology, University of Hawaii, PO Box 1106, Kailua, Hawaii 96734, USA. kloepper@hawaii.edu
authors.forename: Laura N
authors.initials: LN
authors.lastname: Kloepper
authors.forename: Paul E
authors.initials: PE
authors.lastname: Nachtigall
authors.forename: Christopher
authors.initials: C
authors.lastname: Quintos
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Vlachos
mesh_terms: D000162:Acoustics; D000818:Animals; D004192:Discrimination, Psychological / Q000502:physiology; D004289:Dolphins / Q000502:physiology*; D004455:Echolocation / Q000502:physiology*; D005260:Female; D013018:Sound Spectrography