Determining Source Levels Sound Fields and Body Sizes of Singing Humpback Whales (Megaptera novaeangliae) in the Hawaiian Winter Ground

The stereotypical stationary posture adopted by male humpback whales producing song suggests they are attempting to optimize transmission range. Over 23 days between Jan. 28 and Apr. 2 2003, we measured the sound fields of singers using divers equipped with rebreather scuba. A custom-designed "...

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Bibliographic Details
Main Authors: Pack, Adam A., Potter, J., Herman, L. M., Hoffmann-Kuhnt, M., Deakos, M. H.
Other Authors: DOLPHIN INST HONOLULU HI
Format: Text
Language:English
Published: 2003
Subjects:
Biology
*WHALES
MAMMALS
ULTRASONICS
MALES
HAND HELD
HAWAII
DIVERS
ACOUSTIC FIELDS
ANTHROPOMETRY
NOISE(SOUND)
DIGITAL CAMERAS
SINGING HUMPBACK WHALE
DIGITAL VIDEO CAMERAS
MEGAPTERA NOVAEANGLIAER
Humpback Whale
Megaptera novaeangliae
Online Access:http://www.dtic.mil/docs/citations/ADA421803
http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA421803
Description
Summary:The stereotypical stationary posture adopted by male humpback whales producing song suggests they are attempting to optimize transmission range. Over 23 days between Jan. 28 and Apr. 2 2003, we measured the sound fields of singers using divers equipped with rebreather scuba. A custom-designed "Aquahead" system reliably located singers to within 50 m. Fifty seven singers were located using the Aquahead from distances as far away as 6.1 km in as short a time as 3 min. Divers recorded song using digital video cameras while simultaneously measuring depth and range to a singer's head using hand held ultrasonic range finders. Whale body lengths were obtained using videogrammetry. Source levels were measured up to 203 db re 1 micro Pa 1m. Up to a 16dB difference between frontal and lateral intensities (2.2 kHz) was found indicating that song was most intense at locations directly in front of the singer's rostrum. Body lengths were obtained for 18 singers. Sizes ranged from 10.64 to 13.55 m. A larger dataset is required to compare source levels and sound fields of particular units with whale body size.

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