In an underwater environment the physical characteristics of sound propagation differ considerably from those in air. For this reason, sound localization underwater is associated with difficulties, especially in the median plane. It was the approach of the present study to investigate whether harbor seals (Phoca vitulina) are able to determine the direction of a tonal signal form above or below in the underwater environment. Minimum audible angles (MAAs) or the angular range in which the animals could localize a pure tone stimulus in the vertical plane were obtained for frequencies from 0.35 up to 16 kHz. Testing was conducted with four male harbor seals in a semi-circle area of 6 m in diameter in about 2.5 m depth, by using a two alternative forced choice method. The results show that harbor seals are able to localize a pure tone in the median plane under water with a high performance for low frequency stimuli between 350 Hz and 2 kHz with MAAs ranging from below 2.5° up to about 25°. For higher frequencies the animals show strong individual differences.
References
1.
Aroyan
, J. L.
(2001
). “Three-dimensional modeling of hearing in Delphinus delphis
,” J. Acoust. Soc. Am.
110
, 3305
–3318
.2.
Babushina
, E. S.
, and Yurkevich
, L. I.
(1994
). “Vertical plane localization of underwater sound sources by the northern fur seal
,” Sens. Syst.
8
(1
), 55
–57
.3.
Bartsh
, S. S.
, Johnston
, S. D.
, and Siniff
, D. B.
(1992
). “Territorial behavior and breeding frequency of male Weddell seals (Leptonychotes weddelii) in relation to age, size and concentrations of serum testosterone and cortisol
,” Can. J. Zool.
70
, 680
–692
.4.
Batteau
, D. W.
(1967
). “The role of the pinna in human localization
,” Proc. R. Soc. London, Ser. B
168
(1011
), 158
–180
.5.
Bjørgesaeter
, A.
, Ugland
, K. I.
, and Bjørge
, A.
(2004
). “Geographic variation and acoustic structure of the underwater vocalization of harbor seals (Phoca vitulina) in Norway, Sweden and Scotland
,” J. Acoust. Soc. Am.
116
, 2459
–2468
.7.
Blauert
, J.
(1997
). Spatial Hearing: The Psychophysics of Human Sound Localization
(MIT Press
, Cambridge
).8.
Bodson
, A.
, Miersch
, L.
, and Dehnhardt
, G.
(2007
). “Underwater sound localization by harbor seals
,” J. Acoust. Soc. Am.
122
, 2263
–2269
.9.
Bodson
, A.
, Miersch
, L.
, Mauck
, B.
, and Dehnhardt
, G.
(2006
). “Underwater sound localization by a swimming harbor seal
,” J. Acoust. Soc. Am.
120
, 1550
–1557
.10.
Branstetter
, B. K.
, and Mercado
, E.
(2006
). “Sound localization by cetaceans
,” Int. J. Comp. Psychol.
19
, 26
–61
.11.
Bullock
, T. H.
, Grinnel
, A. D.
, Ikezono
, E.
, Kameda
, K.
, Katsuki
, Y.
, Nomoto
, M.
, Sato
, O.
, Suga
, N.
, and Yanagisawa
, K.
(1968
). “Electrophysiological studies of central auditory mechanisms in cetaceans
,” Z. Vergl. Physiol.
59
, 117
–156
.12.
Butler
, R. A.
(1969
). “On the relative usefulness of monaural and binaural cues in locating sound in space
,” Psychonomic Sci.
17
(4
), 245
–246
.13.
Charrier
, I.
, Mathevon
, N.
, and Aubin
, T.
(2013
). “Bearded seal males perceive geographic variations in their trills
,” Behav. Ecol. Sociobiol.
67
, 1679
–1689
.14.
Deecke
, V. B.
, Slater
, P. J. B.
, and Ford
, J. K. B.
(2002
). “Selective habituation shapes acoustic predator recognition in harbor seals
,” Nature (London)
420
, 171
–173
.15.
Dehnhardt
, G.
, Mauck
, B.
, and Bleckmann
, H.
(1998
). “Seal whiskers detect water movements
,” Nature
394
, 235
–236
.16.
Fay
, R. R.
, and Popper
, A. N.
(2005
). “Introduction to sound source localization
,” in Sound Source Localization
, edited by A. N.
Popper
and R. R.
Fay
(Springer
, New York
), pp. 1
–5
.17.
Fuzessery
, Z. M.
(1986
). “Speculations on the role of frequency in sound localization
,” Brain Behav. Evol.
28
, 95
–108
.18.
Gardener
, M. B.
, and Gardener
, R. S.
(1973
). “Problem of localization in the median plane: Effect of pinnae cavity occlusion
,” J. Acoust. Soc. Am.
53
, 400
–409
.19.
Hanggi
, E. B.
, and Schusterman
, R. J.
(1994
). “Underwater acoustic displays and individual variation in male harbor seals, Phoca vitulina
,” Anim. Behav.
48
, 1275
–1283
.20.
Hayes
, S. A.
, Kumar
, A.
, Daniel
, P. C.
, Mellinger
, D. K.
, Harvey
, J. T.
, Southall
, B. L.
, and LeBoeuf
, B. J.
(2004
). “Evaluating the function of the male harbor seal, Phoca vitulina, roar through playback experiments
,” Anim. Behav.
67
, 1133
–1139
.21.
Hebrank
, J.
, and Wright
, D.
(1974
). “Are two ears necessary for localization of sound sources on the median plane?
,” J. Acoust. Soc. Am.
56
, 935
–938
.22.
Holt
, M. M.
, Schusterman
, R. J.
, Kastak
, D.
, and Southall
, B. L.
(2005
). “Localization of aerial pure tones by pinnipeds
,” J. Acoust. Soc. Am.
118
, 3921
–3926
.23.
Holt
, M. M.
, Schusterman
, R. J.
, Southall
, B. L.
, and Kastak
, D.
(2004
). “Localization of aerial broadband noise by pinnipeds
,” J. Acoust. Soc. Am.
115
, 2339
–2345
.24.
Ivarsson
, C.
, De Ribaupierre
, Y.
, and De Ribaupierre
, F.
(1980
). “Functional ear asymmetry in vertical localization
,” Hear. Res.
3
, 241
–247
.25.
Kaatz
, M.
(2002
). “Multiple sound-producing mechanisms in teleost fishes and hypotheses regarding their behavioral significance
,” Bioacoustics
12
, 230
–233
.26.
Kastak
, D.
, and Schusterman
, R. J.
(1998
). “Low-frequency amphibious hearing in pinnipeds: Methods, measurements, noise and ecology
,” J. Acoust. Soc. Am.
103
, 2216
–2228
.27.
Ketten
, D. R.
(2000
). “Cetacean ears
,” in Hearing by Whales and Dolphins
, edited by W. W. L.
Au
, A. N.
Popper
, and R. R.
Fay
(Springer
, New York
), pp. 43
–108
.28.
Lewald
, J.
, and Karnath
, H. O.
(2002
). “The effect of whole-body tilt on sound lateralization
,” Eur. J. Neurosci.
16
, 761
–766
.29.
Lipatov
, N. V.
(1992
). “Underwater hearing in seals: The role of the outer ear
,” in Marine Mammal Sensory Systems
, edited by J. A.
Thomas
, R. A.
Kastelein
, and A. Ya.
Supin
(Plenum
, New York
), pp. 249
–256
.30.
Martin
, R. L.
, and Webster
, W. R.
(1987
). “The auditory spatial acuity of the domestic cat in the interaural horizontal and median vertical planes
,” Hear. Res.
30
, 239
–252
.31.
Middlebrooks
, J. C.
(1992
). “Narrow-band localization related to external ear acoustics
,” J. Acoust. Soc. Am.
92
, 2607
–2624
.32.
Middlebrooks
, J. C.
, Makous
, J. C.
, and Green
, D. M.
(1989
). “Directional sensitivity of sound pressure levels in the human ear canal
,” J. Acoust. Soc. Am.
86
, 89
–109
.33.
Mills
, A. W.
(1958
). “On the minimum audible angle
,” J. Acoust. Soc. Am.
30
, 237
–246
.35.
Møhl
, B.
(1968
). “Hearing in seals
,” in The Behavior and Physiology of Pinnipeds
, edited by R.
Harrison
, R.
Hubbard
, R.
Peterson
, C.
Rice
, and R.
Schusterman
(Appelton-Century
, New York
), pp. 172
–195
.36.
Muller
, B. S.
, and Bovet
, P.
(1999
). “Role of pinnae and head movements in localizing pure tones
,” Swiss J. Psychol.
58
, 170
–179
.37.
Norberg
, R. A.
(1977
). “Occurrence and independent evolution of bilateral ear asymmetry in owls and implications on owl taxonomy
,” Philos. Trans. R. Soc. London, Ser. B
280
, 375
–408
.38.
Norris
, K. S.
, and Harvey
, G. W.
(1974
). “Sound transmission in the porpoise head
,” J. Acoust. Soc. Am.
56
, 659
–664
.39.
Nummela
, S.
, Thewissen
, J. G. M.
, Bajpai
, S.
, Hussain
, S. T.
, and Kumar
, K.
(2007
). “Sound transmission in archaic and modern whales: Anatomical adaptations for underwater hearing
,” Anat. Rec.
290A
, 716
–733
.40.
Pycraft
, W. P.
(1898
). “A contribution towards our knowledge of the morphology of owls
,” Trans. Linn. Soc. Lond. 2nd Ser. Zool.
7
, 223
–276
.41.
Renaud
, D. L.
, and Popper
, A. N.
(1975
). “Sound localization by the bottlenose porpoise Tursiops truncatus
,” J. Exp. Biol.
63
, 569
–585
.42.
Repenning
, C. A.
(1972
). “Underwater hearing in seals: Functional morphology
,” in Functional Anatomy of Marine Mammals
, edited by R.
Harrison
(Academic Press
, London)
, Vol. 1
, pp. 307
–331
.43.
Reysenbach de Haan
, F. W.
(1957
). “Hearing in whales
,” Acta Oto-Laryngolog.
134
, 81
–95
.44.
Rogers
, T. L.
, Cato
, D. H.
, and Bryden
, M. M.
(1996
). “Behavioral significance of underwater vocalizations of captive leopard seals, Hydrurga leptonyx
,” Mar. Mammal Sci.
12
(3
), 414
–427
.45.
Searle
, C. L.
, Braida
, L. A.
, Cuddy
, D. R.
, and Davis
, M. F.
(1975
). “Binaural pinna disparity: Another auditory localization cue
,” J. Acoust. Soc. Am.
57
, 448
–455
.46.
Strutt
, J. W.
, and Rayleigh
, L.
(1907
). “On our perception of sound direction
,” Philos. Mag.
13
, 214
–232
.47.
Van Barnevald
, D. C. P. B. M.
, Van Grotel
, T. J.
, Alberts
, B.
, and Van Opstal
, A. J.
(2011
). “The effect of head roll on perceived auditory zenith
,” Exp. Brain Res.
213
, 235
–243
.48.
Welsch
, U.
, and Riedelsheimer
, B.
(1997
). “Histophysiological observations on the external auditory meatus, middle, and inner ear of the Weddell seal (Leptonychotes weddelli)
,” J. Morphology
234
, 25
–36
.49.
Wightman
, F. L.
, and Kistler
, D. J.
(1992
). “The dominant role of low-frequency interaural time differences in sound localization
,” J. Acoust. Soc. Am.
91
, 1648
–1661
.50.
Wightman
, F. L.
, and Kistler
, D. J.
(1997
). “Monaural sound localization revisited
,” J. Acoust. Soc. Am.
101
, 1050
–1063
.© 2016 Acoustical Society of America.
2016
Acoustical Society of America
You do not currently have access to this content.