Dear Colleagues,
I would like to draw your attention to the following paper, published
in the September edition of the Journal of the Acoustical
Society of America: Vol 118, No.3, Pt.1 pp.1830-1837
Types,
distribution, and seasonal occurrence of sounds attributed to Bryde's
whales (Balaenoptera
edeni) recorded in the eastern tropical Pacific, 1999-2001
Sara L. Heimlich(1), David K. Mellinger(1),
Sharon
L. Nieukirk(1), Christopher
G. Fox(2)
(1) Cooperative
Institute for Marine Resources Studies, Oregon State University, and
NOAA
Pacific Marine Environmental Laboratory, 2030 SE Marine Science Drive,
Newport,
Oregon 97365
(2) National
Geophysical Data Center, National Oceanographic and
Atmospheric Administration, 325 Broadway, E/GC, Boulder, Colorado
80305-3328
Abstract
Vocalizations resembling
known Bryde’s whale sounds were recorded on autonomous hydrophones at
seven
sites in the eastern tropical Pacific. Five short (<3 s)
low-frequency
(<80 Hz ) “phrase” types were observed. “Swept alternating tonal”
phrases
included a 37 Hz tone and often a 25-16 Hz downswept tone, while
“non-swept
alternating tonal” phrases had a predominant tone at 29 Hz and often
additional
tones at 16 Hz and 47 Hz. Alternating tonal phrases were found in 79%
of the
total hours in which phrases were detected, and occurred primarily at
the
eastern hydrophone sites. “Burst-tonal” phrases included tones
that were often preceded by a wide-band burst of noise. The “low
burst-tonal”
phrase contained tones at 19 Hz and 30 Hz, and was detected at five of
the
hydrophone sites. The “high burst-tonal” phrase included a 42 Hz tone
and was
observed only on the northwestern hydrophones. A single “harmonic tone”
phrase
type was observed that included a fundamental tone at 26 Hz and at
least two
harmonics; this phrase was observed exclusively at the eastern
hydrophone
stations. This opportunistic survey has shown that acoustics is an
effective
means of studying this poorly understood, pelagic balaenopterid.
ERRATA:
Page 1834, Section C. Geographic and seasonal occurrence. The first
sentence should read:
Swept and nonswept alternating tonal phrase types were the most
abundant of the five types, comprising 1535 (46.3% and 1097 (33.1%).
respectively, of the total 3315 PTH.
Cheers-
Sara Heimlich
CIMRS/NOAA
Hatfield Marine Science
Center,
2030 SE Marine Science Drive,
Newport,
Oregon 97365
(541) 867-0328