True's beaked whales (Mesoplodon mirus) were encountered on two separate shipboard surveys on 24 July 2016 and 16 September 2017 in the western North Atlantic Ocean. Recordings were made using a hydrophone array towed 300 m behind the ship. In 2016, three different groups were sighted within 1500 m of the ship; clicks were recorded for 26 min. In 2017, a single group of five whales was tracked over the course of five hours in which the ship maintained a distance <4000 m from the group. A total of 2938 frequency-modulated (FM) clicks and 7 buzzes were recorded from both encounters. Plausible inter-click-intervals (ICIs) were calculated from 2763 clicks, and frequency and duration measurements were calculated from 2150 good quality FM clicks. The median peak frequencies were 43.1 kHz (2016, n = 718) and 43.5 kHz (2017, n = 1432). Median ICIs were 0.17 s (2016) and 0.19 s (2017). The spectra and measurements of the recorded clicks closely resemble Gervais's beaked whale clicks (Mesoplodon europaeus) and distinguishing between the two species in acoustic data sets proves difficult. The acoustic behavior of True's beaked whales was previously unknown; this study provides a description of echolocation clicks produced by this species.

1.
Aguilar de Soto
,
N.
,
Madsen
,
P. T.
,
Tyack
,
P.
,
Arranz
,
P.
,
Marrero
,
J.
,
Fais
,
A.
,
Revelli
,
E.
, and
Johnson
,
M.
(
2011
). “
No shallow talk: Cryptic strategy in the vocal communication of Blainville's beaked whales
,”
Mar. Mammal Sci.
28
(
2
),
E75
E92
.
2.
Aguilar de Soto
,
N.
,
Martín
,
V.
,
Silva
,
M.
,
Edler
,
R.
,
Reyes
,
C.
,
Carrillo
,
M.
,
Schiavi
,
A.
,
Morales
,
T.
,
García-Ovide
,
B.
,
Sanchez-Mora
,
A.
,
Garcia-Tavero
,
N.
,
Steiner
,
L.
,
Scheer
,
M.
,
Gockel
,
R.
,
Walker
,
D.
,
Villa
,
E.
,
Szlama
,
P.
,
Eriksson
,
I. K.
,
Tejedor
,
M.
,
Perez-Gil
,
M.
,
Quaresma
,
J.
,
Bachara
,
W.
, and
Carroll
,
E.
(
2017
). “
True's beaked whale (Mesoplodon mirus) in Macaronesia
,”
PeerJ
5
,
3059
.
3.
Au
,
W. W. L.
(
1993
).
The Sonar of Dolphins
(
Springer
,
New York
).
4.
Baumann-Pickering
,
S.
,
McDonald
,
M. A.
,
Simonis
,
A. E.
,
Solsona Berga
,
A.
,
Merkens
,
K. P. B.
,
Oleson
,
E. M.
,
Roch
,
M. A.
,
Wiggins
,
S. M.
,
Rankin
,
S.
,
Yack
,
T. M.
, and
Hildebrand
,
J. A.
(
2013a
). “
Species-specific beaked whale echolocation signals
,”
J. Acoust. Soc. Am.
134
,
2293
2301
.
5.
Baumann-Pickering
,
S.
,
Roch
,
M. A.
,
Brownell
,
R. L.
, Jr.
,
Simonis
,
A. E.
,
McDonald
,
M. A.
,
Solsona-Berga
,
A.
,
Oleson
,
E. M.
,
Wiggins
,
S. M.
, and
Hildebrand
,
J. A.
(
2014
). “
Spatio-temporal patterns of beaked whale echolocation signals in the North Pacific
,”
PLoS One
9
,
e86072
.
6.
Baumann-Pickering
,
S.
,
Yack
,
T. M.
,
Barlow
,
J.
,
Wiggins
,
S. M.
, and
Hildebrand
,
J. A.
(
2013b
). “
Baird's beaked whale echolocation signals
,”
J. Acoust. Soc. Am.
133
,
4321
4331
.
7.
Bioacoustics Research Program
. (
2014
).
Raven Pro: Interactive Sound Analysis Software
(
The Cornell Lab of Ornithology
,
Ithaca, NY
).
8.
Cholewiak
,
D.
,
Baumann-Pickering
,
S.
, and
Van Parijs
,
S.
(
2013
). “
Description of sounds associated with Sowerby's beaked whales (Mesoplodon bidens) in the western North Atlantic Ocean
,”
J. Acoust. Soc. Am.
134
,
3905
3912
.
9.
Dalebout
,
M. L.
,
Steel
,
D.
, and
Baker
,
C. S.
(
2008
). “
Phylogeny of the beaked whale genus Mesoplodon (Ziphiidae: Cetacea) revealed by nuclear introns: Implications for the evolution of male tusks
,”
Syst. Biol.
57
,
857
875
.
10.
Dawson
,
S.
, and
Ljungblad
,
D.
(
1998
). “
Sounds recorded from Baird's beaked whale, Berardius bairdii
,”
Mar. Mammal Sci.
14
,
335
344
.
11.
DeAngelis
,
A. I.
,
Valtierra
,
R.
,
Van Parijs
,
S. M.
, and
Cholewiak
,
D.
(
2017
). “
Using multipath reflections to obtain dive depths of beaked whales from a towed hydrophone array
,”
J. Acoust. Soc. Am.
142
,
1078
1087
.
12.
Gillespie
,
D.
,
Dunn
,
C.
,
Gordon
,
J.
,
Claridge
,
D.
,
Embling
,
C.
, and
Boyd
,
I.
(
2009
). “
Field recordings of Gervais' beaked whales Mesoplodon europaeus from the Bahamas
,”
J. Acoust. Soc. Am.
125
,
3428
3433
.
13.
Gillespie
,
D.
,
Mellinger
,
D. K.
,
Gordon
,
J.
,
McLaren
,
D.
,
Redmond
,
P.
,
McHugh
,
R.
,
Trinder
,
P.
,
Deng
,
X. Y.
, and
Thode
,
A.
(
2008
). “
PAMGUARD: Semiautomated, open source software for real-time acoustic detection and localisation of cetaceans
,”
Proc. Inst. Acoust.
30
,
54
62
.
14.
Hernandez-Milian
,
G.
,
Lusher
,
A.
,
O'Brian
,
J.
,
Fernandez
,
A.
,
O'Connor
,
I.
,
Berrow
,
S.
, and
Rogan
,
E.
(
2017
). “
New information on the diet of True's beaked whale (Mesoplodon mirus, Gray 1850), with insights into foraging ecology on mesopelagic prey
,”
Mar. Mammal Sci.
33
,
1245
1254
.
15.
Hildebrand
,
J. A.
,
Baumann-Pickering
,
S.
,
Frasier
,
K. E.
,
Trickey
,
J. S.
,
Merkens
,
K. P.
,
Wiggins
,
S. M.
,
McDonald
,
M. A.
,
Garrison
,
L. P.
,
Harris
,
D.
,
Marques
,
T. A.
, and
Thomas
,
L.
(
2015
). “
Passive acoustic monitoring of beaked whale densities in the Gulf of Mexico
,”
Sci. Rep.
5
,
1
15
.
16.
Hooker
,
S. K.
, and
Whitehead
,
H.
(
2002
). “
Click characteristics of northern bottlenose whales (Hyperoodon ampullatus)
,”
Mar. Mammal Sci.
18
,
69
80
.
17.
Johnson
,
M.
,
Hickmott
,
L. S.
,
Soto
,
N. A.
, and
Madsen
,
P. T.
(
2008
). “
Echolocation behaviour adapted to prey in foraging Blainville's beaked whale (Mesoplodon densirostris)
,”
Proc. Biol. Sci.
275
,
133
139
.
18.
Johnson
,
M.
,
Madsen
,
P. T.
,
Zimmer
,
W. M. X.
,
de Soto
,
N. A.
, and
Tyack
,
P. L.
(
2004
). “
Beaked whales echolocate on prey
,”
Proc. Biol. Sci.
271
,
S383
S386
.
19.
Johnson
,
M.
,
Madsen
,
P. T.
,
Zimmer
,
W. M. X.
,
de Soto
,
N. A.
, and
Tyack
,
P. L.
(
2006
). “
Foraging Blainville's beaked whales (Mesoplodon densirostris) produce distinct click types matched to different phases of echolocation
,”
J. Exp. Biol.
209
,
5038
5050
.
20.
Keating
,
J. L.
,
Barlow
,
J.
, and
Rankin
,
S.
(
2016
). “
Shifts in frequency-modulated pulses recorded during an encounter with Blainville's beaked whales (Mesoplodon densirostris)
,”
J. Acoust. Soc. Am.
140
,
EL166
EL171
.
21.
Küsel
,
E. T.
,
Mellinger
,
D. K.
,
Thomas
,
L.
,
Marques
,
T. A.
,
Moretti
,
D.
, and
Ward
,
J.
(
2011
). “
Cetacean population density estimation from single fixed sensors using passive acoustics
,”
J. Acoust. Soc. Am.
129
,
3610
3622
.
22.
MacLeod
,
C. D.
,
Perrin
,
W. F.
,
Pitman
,
R.
,
Barlow
,
J.
,
Ballance
,
L.
,
D'Amico
,
A.
,
Gerrodette
,
T.
,
Joyce
,
G.
,
Mullin
,
K. D.
,
Palka
,
D. L.
, and
Waring
,
G. T.
(
2006a
). “
Known and inferred distributions of beaked whale species (Cetacea: Ziphiidae)
,”
J. Cetacean Res. Manage.
7
,
271
286
.
23.
MacLeod
,
C. D.
,
Santos
,
M. B.
,
López
,
A.
, and
Pierce
,
G. J.
(
2006b
). “
Relative prey size consumption in toothed whales: Implications for prey selection and level of specialisation
,”
Mar. Ecol. Prog. Ser.
326
,
295
307
.
24.
MacLeod
,
C. D.
,
Santos
,
M. B.
, and
Pierce
,
G. J.
(
2003
). “
Review of data on diets of beaked whales: Evidence of niche separation and geographic segregation
,”
J. Mar. Biol. Assoc. U. K.
83
,
651
665
.
25.
Madsen
,
P. T.
,
Johnson
,
M. P.
,
Aguilar De Soto
,
N.
,
Zimmer
,
W. M. X.
, and
Tyack
,
P. L.
(
2005
). “
Biosonar performance of foraging beaked whales (Mesoplodon densirostris)
,”
J. Exp. Biol.
208
,
181
194
.
26.
McDonald
,
M. A.
,
Hildebrand
,
J. A.
,
Wiggins
,
S. M.
,
Johnston
,
D. W.
, and
Polovina
,
J. J.
(
2009
). “
An acoustic survey of beaked whales at Cross Seamount near Hawaii
,”
J. Acoust. Soc. Am.
125
,
624
627
.
27.
Palka
,
D.
,
Cholewiak
,
D.
,
Broughton
,
E.
, and
Jech
,
M.
(
2016
). “
Appendix A: Northern leg of shipboard abundance survey during 27 June–25 August 2016: Northeast Fisheries Science Center
,” Annual Report of a Comprehensive Assessment of Marine Mammal, Marine Turtle, and Seabird Abundance and Spatial Distribution in US Waters of the Western North Atlantic Ocean- AMAPPS II, pp. 10–60, available at https://www.nefsc.noaa.gov/psb/AMAPPS/docs/Annual%20Report%20of%202016%20AMAPPS_final.pdf.
28.
Rankin
,
S.
, and
Barlow
,
J.
(
2007
). “
Sounds recorded in the presence of Blainville's beaked whales, Mesoplodon densirostris, near Hawai'i
,”
J. Acoust. Soc. Am.
122
,
42
45
.
29.
Rankin
,
S.
,
Baumann-Pickering
,
S.
,
Yack
,
T.
, and
Barlow
,
J.
(
2011
). “
Description of sounds recorded from Longman's beaked whale, Indopacetus pacificus
,”
J. Acoust. Soc. Am.
130
,
EL339
EL344
.
30.
Roch
,
M. A.
,
Klinck
,
H.
,
Baumann-Pickering
,
S.
,
Mellinger
,
D. K.
,
Qui
,
S.
,
Soldevilla
,
M. S.
, and
Hildebrand
,
J. A.
(
2011
). “
Classification of echolocation clicks from odontocetes in the Southern California Bight
,”
J. Acoust. Soc. Am.
129
,
467
475
.
31.
Shaffer
,
J. W.
,
Moretti
,
D.
,
Jarvis
,
S.
,
Tyack
,
P.
, and
Johnson
,
M.
(
2013
). “
Effective beam pattern of the Blainville's beaked whale (Mesoplodon densirostris) and implications for passive acoustic monitoring
,”
J. Acoust. Soc. Am.
133
,
1770
1784
.
32.
Sjölander
,
K.
, and
Beskow
,
J.
(
2000
). “
Wavesurfer—An open source speech tool
,” in
ICSLP-2000
, Beijing, China, pp.
464
467
.
33.
Soldevilla
,
M. S.
,
Henderson
,
E. E.
,
Campbell
,
G. S.
,
Wiggins
,
S. M.
,
Hildebrand
,
J. A.
, and
Roch
,
M. A.
(
2008
). “
Classification of Risso's and Pacific white-sided dolphins using spectral properties of echolocation clicks
,”
J. Acoust. Soc. Am.
124
,
609
624
.
34.
Stanistreet
,
J. E.
,
Nowacek
,
D. P.
,
Baumann-Pickering
,
S.
,
Bell
,
J. T.
,
Cholewiak
,
D. M.
,
Hildebrand
,
J. A.
,
Hodge
,
L. E. W.
,
Moors-Murphy
,
H. B.
,
Van Parijs
,
S. M.
, and
Read
,
A. J.
(
2017
). “
Using passive acoustic monitoring to document the distribution of beaked whale species in the western North Atlantic Ocean
,”
Can. J. Fish. Aquat. Sci.
74
,
2098
2109
.
35.
Tyack
,
P. L.
,
Johnson
,
M.
,
Soto
,
N. A.
,
Sturlese
,
A.
, and
Madsen
,
P. T.
(
2006
). “
Extreme diving of beaked whales
,”
J. Exp. Biol.
209
,
4238
4253
.
36.
Wahlberg
,
M.
,
Beedholm
,
K.
,
Heerfordt
,
A.
, and
Mohl
,
B.
(
2011
). “
Characteristics of biosonar signals from the northern bottlenose whale, Hyperoodon ampullatus
,”
J. Acoust. Soc. Am.
130
,
3077
3084
.
37.
Wenzel
,
F. W.
,
Polloni
,
P. T.
,
Craddock
,
J. E.
,
Gannon
,
D. P.
,
Nicolas
,
J. R.
,
Read
,
A. J.
, and
Rosel
,
P. E.
(
2013
). “
Food habits of Sowerby's beaked whales (Mesoplodon bidens) taken in the pelagic drift gillnet fishery of the western North Atlantic
,”
Fish. Bull.
111
,
381
389
.
38.
Zimmer
,
W. M. X.
(
2011
).
Passive Acoustic Monitoring of Cetaceans
(
Cambridge University Press
,
New York)
.
39.
Zimmer
,
W. M. X.
,
Harwood
,
J.
,
Tyack
,
P. L.
,
Johnson
,
M. P.
, and
Madsen
,
P. T.
(
2008
). “
Passive acoustic detection of deep-diving beaked whales
,”
J. Acoust. Soc. Am.
124
,
2823
2832
.
40.
Zimmer
,
W. M. X.
,
Johnson
,
M. P.
,
Madsen
,
P. T.
, and
Tyack
,
P. L.
(
2005
). “
Echolocation clicks of free-ranging Cuvier's beaked whales (Ziphius cavirostris)
,”
J. Acoust. Soc. Am.
117
,
3919
3927
.

Supplementary Material

You do not currently have access to this content.