title: Atlantic bottlenose dolphin (Tursiops truncatus) hearing threshold for brief broadband signals.
abstract: The hearing sensitivity of an Atlantic bottlenose dolphin (Tursiops truncatus) to both pure tones and broadband signals simulating echoes from a 7.62-cm water-filled sphere was measured. Pure tones with frequencies between 40 and 140 kHz in increments of 20 kHz were measured along with broadband thresholds using a stimulus with a center frequency of 97.3 kHz and 88.2 kHz. The pure-tone thresholds were compared with the broadband thresholds by converting the pure-tone threshold intensity to energy flux density. The results indicated that dolphins can detect broadband signals slightly better than a pure-tone signal. The broadband results suggest that an echolocating bottlenose dolphin should be able to detect a 7.62-cm diameter water-filled sphere out to a range of 178 m in a quiet environment.
authors.affiliation: Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii, Kailua 96734, USA. wau@hawaii.edu
authors.forename: Whitlow W L
authors.initials: WW
authors.lastname: Au
authors.forename: David W
authors.initials: DW
authors.lastname: Lemonds
authors.forename: Stephanie
authors.initials: S
authors.lastname: Vlachos
authors.forename: Paul E
authors.initials: PE
authors.lastname: Nachtigall
authors.forename: Herbert L
authors.initials: HL
authors.lastname: Roitblat
mesh_terms: D000818:Animals; D001070:Appetitive Behavior; D001309:Auditory Threshold; D004289:Dolphins / Q000523:psychology*; D004455:Echolocation; D005260:Female; D010897:Pitch Discrimination; D011571:Psychoacoustics; D013018:Sound Spectrography