title: Beaked whale auditory evoked potential hearing measurements.
abstract: Several mass strandings of beaked whales have recently been correlated with military exercises involving mid-frequency sonar highlighting unknowns regarding hearing sensitivity in these species. We report the hearing abilities of a stranded juvenile beaked whale (Mesoplodon europaeus) measured with auditory evoked potentials. The beaked whale's modulation rate transfer function (MRTF) measured with a 40-kHz carrier showed responses up to an 1,800 Hz amplitude modulation (AM) rate. The MRTF was strongest at the 1,000 and 1,200 Hz AM rates. The envelope following response (EFR) input-output functions were non-linear. The beaked whale was most sensitive to high frequency signals between 40 and 80 kHz, but produced smaller evoked potentials to 5 kHz, the lowest frequency tested. The beaked whale hearing range and sensitivity are similar to other odontocetes that have been measured.
authors.affiliation: College of Marine Science, University of South Florida, St. Petersburg, FL 33701-5016, USA. mhill@marine.usf.edu
authors.forename: Mandy L H
authors.initials: ML
authors.lastname: Cook
authors.forename: René A
authors.initials: RA
authors.lastname: Varela
authors.forename: Juli D
authors.initials: JD
authors.lastname: Goldstein
authors.forename: Stephen D
authors.initials: SD
authors.lastname: McCulloch
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Bossart
authors.forename: James J
authors.initials: JJ
authors.lastname: Finneran
authors.forename: Dorian
authors.initials: D
authors.lastname: Houser
authors.forename: David A
authors.initials: DA
authors.lastname: Mann
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001309:Auditory Threshold / Q000502:physiology*; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005583:Fourier Analysis; D007568:Jaw / Q000502:physiology; D008297:Male; D010898:Pitch Perception / Q000502:physiology*; D014907:Whales / Q000502:physiology*