AUDITORY THRESHOLDS OF THE BOTTLENOSED PORPOISE (TURSIOPS TRUNCATUS, MONTAGU)
Abstract
Standard operant conditioning techniques were used to train a bottlenosed porpoise to respond to pure tone signals by pushing a lever-operated switch. An audiogram was obtained over the frequency range from 75 hertz to 150 kHz. The lowest thresholds (greatest hearing sensitivity) occurred in the frequencies near 50 kHz at a level of about -55 decibels (re 1 microbar). The effective upper limit of hearing for the experimental animal was determined to be 150 kHz. There was no indication of sensitivity to near-field displacements such as those observed in fish.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1966
- Accession Number
- AD0643381
Entities
People
- C S Johnson
Organizations
- Naval Air Weapons Station China Lake