In:
Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 140, No. 4_Supplement ( 2016-10-01), p. 3131-3132
Abstract:
Transmission beam characteristics have been described in a small number of odontocete species, providing insight into the biological and ecological factors that have influenced the design of the outgoing echolocation beam. The current study measured the on-axis spectral characteristics and transmission beam pattern of echolocation clicks from a small oceanic delphinid, the spinner dolphin (Stenella longirostis). A formerly stranded individual was rehabilitated in captivity and trained to station underwater in front of a 16 element hydrophone array. Preliminary analysis of a subset of recorded clicks showed on-axis spectral characteristics with a mean center frequency of 68 kHz and a mean peak frequency of 52 kHz. The dolphin exhibited both a circular beam shape and also varying degrees of a dorso-ventrally compressed transmission beam. The mean angular beamwidth for all clicks was 16.6 and 14.3 degrees in the horizontal and vertical planes, respectively, though some clicks exhibited horizontal beamwidths that were almost twice as wide as the vertical beamwidth. The overall beam was generally broader than the beams of previously described species, with a mean directivity index for all clicks of 21.5 dB. These results are the first reports of transmission beam characteristics from a spinner dolphin.
Type of Medium:
Online Resource
ISSN:
0001-4966
,
1520-8524
Language:
English
Publisher:
Acoustical Society of America (ASA)
Publication Date:
2016
detail.hit.zdb_id:
1461063-2
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