title: A practical weighting function for harbor porpoise underwater sound level measurements.
abstract: Harbor porpoise (Phocoena phocoena) are subject to underwater noise disturbance from anthropogenic sources, especially shipping. The underwater audiograms of harbor porpoise were used to create a frequency weighting function, dBht(Phocoena phocoena), to permit estimation of the broadband perceived amplitudes of ambient and shipping noise. An equation was fit to the 0.02-20 kHz range of unmasked detection thresholds and normalizing to 0 dB at 20 kHz; dB = 46.4-35.6 log(kHz). The weighting function de-emphasizes the low frequency components of noise. Harbor porpoise hearing is less sensitive to low frequency shipping noise and, except at high amplitudes, estimating potential noise impacts using linear measurements will be misleading.
authors: Department of Biology, University of New Brunswick, PO Box 5050, Saint John, New Brunswick E2L 4L5, Canada. terhune@unb.ca
authors: John M
authors: JM
authors: Terhune
mesh_terms: D000162:Acoustics; D000818:Animals; D001309:Auditory Threshold; D004784:Environmental Monitoring / Q000379:methods*; D008386:Marine Biology / Q000379:methods*; D008962:Models, Theoretical; D009624:Noise, Transportation / Q000009:adverse effects*; D050741:Phocoena / Q000502:physiology* / Q000523:psychology; D012767:Ships; D017603:Signal Detection, Psychological; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography