• Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

You are not logged in You are logged out of this journal. Log In

Journal of the Acoustical Society of America / Volume 131 / Issue 1 / BIOACOUSTICS [80]

The biosonar field around an Atlantic bottlenose dolphin (Tursiops truncatus)

J. Acoust. Soc. Am. Volume 131, Issue 1, pp. 569-576 (2012); (8 pages)

Whitlow W. L. Au1, Brian Branstetter2, Patrick W. Moore2, and James J. Finneran3

1Marine Mammal Research Program, Hawaii Institute of Marine Biology, P. O. Box 1106, Kailua, Hawaii 96734
2National Marine Mammal Foundation, 2240 Shelter Island Drive, #200, San Diego, California 92106
3US Navy Marine Mammal Program, SSC Pacific Code 71510 53560 Hull Street, San Diego, California 92152

Full Text: Read Online (HTML) | Download PDF | Buy PDF (US$30) | View Cart
The use of remote autonomous passive acoustic recorders (PAR) to determine the distribution of dolphins at a given locations has become very popular. Some investigators are using echolocation clicks to gather information on the presence of dolphins and to identify species. However, in all of these cases, the PAR probably recorded mainly off-axis clicks, even some from behind the animals. Yet there is a very poor understanding of the beam pattern and the click waveform and spectrum from different azimuths around the animal’s body. The beam pattern completely around an echo locating dolphin was measured at 16 different but equally spaced angles in the horizontal plane using an 8-hydrophone array in sequence. Eight channels of data were digitized simultaneously at a sampling rate of 500 kHz. The resulting beam patterns in both planes showed a continuous drop off in sound pressure with azimuth around the animal and reached levels below −50 dB relative to the signal recorded on the beam axis. The signals began to break up into two components at angles greater than ± 45° in the horizontal plane. The center frequency dropped off from its maximum at 0° in a non-uniform matter.

© 2012 Acoustical Society of America

ACKNOWLEDGEMENT

This work was supported by the Office of Naval Research, Code 32, Michael Weise, program manager. We express our appreciation to Megan Tormey, Linda Green and Hitomi Aihara who did the animal training/handling during this experiment. This study was conducted under the approval of the SSC Pacific Institutional Animal Care and Use Committee (IACUC) and met the ASA standards for animal studies. This is HIMB contribution #1473.

Article Outline

  1. INTRODUCTION
  2. APPROACH
  3. RESULTS
    1. Horizontal beam pattern
    2. Waveform and spectrum in horizontal plane
    3. Vertical beam pattern
    4. Waveform and spectrum in the vertical plane
    5. Signal parameters
  4. DISCUSSION AND CONCLUSIONS

RELATED DATABASES

To view database links for this article, you need to log in.

KEYWORDS and PACS

Keywords

echo, hydrophones, recorders, sonar arrays, sonar signal processing, underwater sound

PACS

  • 43.80.Ka

    Sound production by animals: mechanisms, characteristics, populations, biosonar

ARTICLE DATA

History
Received 05 Jul 2011
Accepted 24 Oct 2011
Digital Object Identifier
http://dx.doi.org/10.1121/1.3662077

PUBLICATION DATA

ISSN

0001-4966 (print)  

Publisher

$abstract.society.value is a Member of CrossRef Acoustical Society of America

For access to fully linked references, you need to log in.

Figures (9)

Access to article objects (figures, tables, multimedia) requires a subscription; log in to view available files.
(Access to supplementary files, where available, is free for this journal.)



Close

Your Recent History Recent History Help

Recently Viewed

  1. The biosonar field around an Atlantic bottlenose dolphin (Tursiops truncatus)
  2. Modeling of thermal effects in antivascular ultrasound therapy
  3. Properties of underwater acoustic communication channels in shallow water

Home Publications Meetings Contact ASA Site Map Back to Top

Copyright © Acoustical Society of America

close