Relation of Pure Tone Thresholds to Background Noise Level in the Atlantic Cod ( Gadus morhua )

• Published in: Journal of the Fisheries Research Board of Canada
• Main Author: Buerkle, Udo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1968
• Subjects: General Medicine; atlantic cod; Gadus morhua
• Online Access: http://dx.doi.org/10.1139/f68-101; http://www.nrcresearchpress.com/doi/pdf/10.1139/f68-101

A conditioning procedure was used to determine auditory thresholds of cod at frequencies 35.3, 70.7, 141, 283, and 400 Hz at four levels of background noise. The noise was produced in octave bands centered at the test frequencies, and ranged in level from −14 db to +4 db (re 1 microbar). Up to 283 Hz thresholds varied directly with background noise, and signal-to-noise levels at thresholds remained approximately the same at all background noise levels for each frequency. Thresholds at 400 Hz were much higher and showed no relationship to noise. Mean signal-to-noise levels are calculated.