title: Whole-lung resonance in a bottlenose dolphin (Tursiops truncatus) and white whale (Delphinapterus leucas).
abstract: An acoustic backscatter technique was used to estimate in vivo whole-lung resonant frequencies in a bottlenose dolphin (Tursiops truncatus) and white whale (Delphinapterus leucas). Subjects were trained to submerge and position themselves near an underwater sound projector and a receiving hydrophone. Acoustic pressure measurements were made near the thorax while the subject was insonified with pure tones at frequencies from 16 to 100 Hz. Whole-lung resonant frequencies were estimated by comparing pressures measured near the subject's thorax to those measured from the same location without the subject present. Experimentally measured resonant frequencies for the white whale and dolphin lungs were 30 and 36 Hz, respectively. These values were significantly higher than those predicted using a free-spherical air bubble model. Experimentally measured damping ratios and quality factors at resonance were 0.20 and 2.5, respectively, for the white whale, and 0.16 and 3.1, respectively, for the dolphin.
authors.affiliation: Space and Naval Warfare Systems Center, San Diego, Code 2351, 53560 Hull Street, San Diego, California 92152-5001, USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: Finneran
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D004289:Dolphins / Q000502:physiology*; D005260:Female; D008168:Lung / Q000000981:diagnostic imaging / Q000502:physiology*; D055370:Lung Injury; D008297:Male; D009622:Noise / Q000009:adverse effects; D018570:Risk Assessment; D012542:Scattering, Radiation; D013018:Sound Spectrography; D014057:Tomography, X-Ray Computed; D014907:Whales / Q000502:physiology*