Temporary threshold shift in a bottlenose dolphin (Tursiops truncatus) exposed to intermittent tones.
Temporary threshold shift (TTS) was measured in a bottlenose dolphin exposed to a sequence of four 3-kHz tones with durations of 16 s and sound pressure levels (SPLs) of 192 dB re 1 μPa. The tones were separated by 224 s of silence, resulting in duty cycle of approximately 7%. The resulting growth and recovery of TTS were compared to experimentally measured TTS in the same subject exposed to single, continuous tones with similar SPLs. The data confirm the potential for accumulation of TTS across multiple exposures and for recovery of hearing during the quiet intervals between exposures. The degree to which various models could predict the growth of TTS across multiple exposures was also examined.
US Navy Marine Mammal Program, SSC Pacific Code 71510, 53560 Hull Street, San Diego, California 92152, USA.
James J
JJ
Finneran
Donald A
DA
Carder
Carolyn E
CE
Schlundt
Randall L
RL
Dear
D000161:Acoustic Stimulation; D000222:Adaptation, Physiological; D000818:Animals; D001309:Auditory Threshold; D050681:Bottle-Nosed Dolphin / Q000502:physiology*; D005260:Female; D009622:Noise / Q000009:adverse effects*; D011312:Pressure; D011571:Psychoacoustics; D013997:Time Factors