Very-High-Frequency Acoustic Emissions from the White-Beaked Dolphin (Lagenorhynchus Albirostris)

  • Ronald B. Mitson
Part of the NATO ASI Series book series (NSSA, volume 196)

Abstract

Reception by sonar of the signals on board the Ministry of Agriculture, Fisheries and Food’s (MAFF’s) research vessel, CLIONE, from a school of white-beaked dolphins (Lagenorhynchus albirostris), shows that there is significant energy in their acoustic emissions to at least 325 kHz. A sector scanning sonar of 0.33° bearing resolution and 100 μs time resolution was used in active and passive modes when the dolphins approached the ship. Examples of the recorded pulse signals are shown in photographic sequences. Some of the analysed pulse rates varied from 100 to 750 pulses per second when averaged over 20ms periods. Crude estimates of the source level of the signals are between 123 to greater than 207 dB re 1 μPa at 1 m.

Keywords

Acoustic Emission Source Level Tidal Stream Spherical Spreading Signal Train 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer Science+Business Media New York 1990

Authors and Affiliations

  • Ronald B. Mitson
    • 1
  1. 1.Fisheries LaboratoryMinistry of Agriculture, Fisheries and FoodLowestoft SuffolkUK

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