Killer whales occur in the Arctic but few data exist regarding the ecotypes present. The calling behavior differs among ecotypes, which can be distinguished based on pulsed call type, call rate, and bandwidth. In this study, a passive acoustic recorder was deployed 75 km off Point Hope, Alaska, in the southeastern Chukchi Sea to identify which ecotypes were present. A total of 1323 killer whale pulsed calls were detected on 38 of 276 days during the summers (June–August) of 2013–2015. The majority of calls (n = 804, 61%) were recorded in 2013 with the most calls recorded in July (76% of total calls). The calls were manually grouped into six categories: multipart, downsweep, upsweep, modulated, single modulation, and flat. Most detections were flat (n = 485, 37%) or multipart calls (n = 479, 36%), which contained both high and low frequency components. Call comparisons with those reported in the published literature showed similarities with other transient populations in fundamental frequency contour point distribution and median frequency. This study provides the first comprehensive catalog of transient killer whale calls in this region as well as reports on previously undescribed calls.

1.
Aerts
,
L. A.
,
McFarland
,
A. E.
,
Watts
,
B. H.
,
Lomac-MacNair
,
K. S.
,
Seiser
,
P. E.
,
Wisdom
,
S. S.
,
Kirk
,
A. V.
, and
Schudel
,
C. A.
(
2013
). “
Marine mammal distribution and abundance in an offshore sub-region of the northeastern Chukchi Sea during the open-water season
,”
Cont. Shelf Res.
67
,
116
126
.
2.
Au
,
W. W.
,
Ford
,
J. K.
,
Horne
,
J. K.
, and
Allman
,
K. A. N.
(
2004
). “
Echolocation signals of free-ranging killer whales (Orcinus orca) and modeling of foraging for chinook salmon (Oncorhynchus tshawytscha
),”
J. Acoust. Soc. Am.
115
,
901
909
.
3.
Baird
,
R. W.
,
Abrams
,
P. A.
, and
Dill
,
L. M.
(
1992
). “
Possible indirect interactions between transient and resident killer whales: Implications for the evolution of foraging specializations in the genus Orcinus
,”
Oecologia.
89
,
125
132
.
4.
Barrett-Lennard
,
L. G.
,
Ford
,
J. K.
, and
Heise
,
K. A.
(
1996
). “
The mixed blessing of echolocation: Differences in sonar use by fish-eating and mammal-eating killer whales
,”
Anim. Behav.
51
,
553
565
.
5.
Barrett-Lennard
,
L. G.
,
Matkin
,
C. O.
,
Durban
,
J. W.
,
Saulitis
,
E. L.
, and
Ellifrit
,
D.
(
2011
). “
Predation on gray whales and prolonged feeding on submerged carcasses by transient killer whales at Unimak Island, Alaska
,”
Mar. Ecol. Prog. Ser.
421
,
229
241
.
6.
Bluhm
,
B. A.
,
Coyle
,
K. O.
,
Konar
,
B.
, and
Highsmith
,
R.
(
2007
). “
High gray whale relative abundances associated with an oceanographic front in the south-central Chukchi Sea
,”
Deep-Sea Res. Pt II Top. Stud. Oceanogr.
54
,
2919
2933
.
7.
Clarke
,
J. T.
, and
Moore
,
S. E.
(
2002
). “
A note on observations of gray whales in the southern Chukchi and northern Bering Seas, August–November, 1980–89
,”
J. Cetacean Res. Manage.
4
,
283
288
.
8.
Clarke
,
J.
,
Stafford
,
K.
,
Moore
,
S. E.
,
Rone
,
B.
,
Aerts
,
L.
, and
Crance
,
J.
(
2013
). “
Subarctic cetaceans in the southern Chukchi Sea: Evidence of recovery or response to a changing ecosystem
,”
Oceanography
26
,
136
149
.
9.
Clarke
,
J. T.
,
Ferguson
,
M. C.
,
Curtice
,
C.
, and
Harrison
,
J.
(
2015
). “
8. Biologically Important Areas for Cetaceans Within US Waters—Arctic Region
,”
Aquat. Mamm.
41
(
1
),
94
103
.
10.
Dalheim
,
M. E.
,
Schulman‐Janiger
,
A.
,
Black
,
N.
,
Ternullo
,
R.
,
Ellifrit
,
D.
, and
Balcomb
,
K. C.
 III
(
2008
). “
Eastern temperate North Pacific offshore killer whales (Orcinus orca): Occurrence, movements, and insights into feeding ecology
,”
Mar. Mammal Sci.
24
,
719
729
.
11.
Deecke
,
V. B.
,
Barrett-Lennard
,
L. G.
,
Spong
,
P.
, and
Ford
,
J. K.
(
2010
). “
The structure of stereotyped calls reflects kinship and social affiliation in resident killer whales (Orcinus orca)
,”
Naturwissenschaften
97
,
513
518
.
12.
Deecke
,
V. B.
,
Ford
,
J. K.
, and
Slater
,
P. J.
(
2005
). “
The vocal behaviour of mammal-eating killer whales: Communicating with costly calls
,”
Anim. Behav.
69
,
395
405
.
13.
Deecke
,
V. B.
,
Ford
,
J. K.
, and
Spong
,
P.
(
2000
). “
Dialect change in resident killer whales: Implications for vocal learning and cultural transmission
,”
Anim. Behav.
60
,
629
638
.
14.
Estes
,
J. A.
,
Tinker
,
M. T.
,
Williams
,
T. M.
, and
Doak
,
D. F.
(
1998
). “
Killer whale predation on sea otters linking oceanic and nearshore ecosystems
,”
Science
282
,
473
476
.
15.
Fearnbach
,
H.
,
Durban
,
J. W.
,
Ellifrit
,
D. K.
,
Waite
,
J. M.
,
Matkin
,
C. O.
,
Lunsford
,
C. R.
,
Peterson
,
M. J.
,
Barlow
,
J.
, and
Wade
,
P. R.
(
2014
). “
Spatial and social connectivity of fish-eating ‘resident’ killer whales (Orcinus orca) in the northern North Pacific
,”
Mar. Biol.
161
,
459
472
.
16.
Filatova
,
O. A.
,
Fedutin
,
I. D.
,
Burdin
,
A. M.
, and
Hoyt
,
E.
(
2007
). “
The structure of the discrete call repertoire of killer whales Orcinus orca from Southeast Kamchatka
,”
Bioacoustics
16
,
261
280
.
17.
Filatova
,
O. A.
,
Ford
,
J. K.
,
Matkin
,
C. O.
,
Barrett-Lennard
,
L. G.
,
Burdin
,
A. M.
, and
Hoyt
,
E.
(
2012
). “
Ultrasonic whistles of killer whales (Orcinus orca) recorded in the North Pacific (L)
,”
J. Acoust. Soc. Am.
132
,
3618
3621
.
18.
Filatova
,
O. A.
,
Miller
,
P. J.
,
Yurk
,
H.
,
Samarra
,
F. I.
,
Hoyt
,
E.
,
Ford
,
J. K.
,
Matkin
,
C. O.
, and
Barrett-Lennard
,
L. G.
(
2015
). “
Killer whale call frequency is similar across the oceans, but varies across sympatric ecotypes
,”
J. Acoust. Soc. Am.
138
,
251
257
.
19.
Foote
,
A. D.
, and
Nystuen
,
J. A.
(
2008
). “
Variation in call pitch among killer whale ecotypes
,”
J. Acoust. Soc. Am.
123
,
1747
1752
.
20.
Ford
,
J. K.
, and
Fisher
,
H. D.
(
1983
). “
Group-specific dialects of killer whales (Orcinus orca) in British Columbia
,” in
Communication and Behavior of Whales
(
Westview
,
Boulder, CO
), Vol.
76
, pp.
129
161
.
21.
Ford
,
J. K.
(
1987
). “
A catalogue of underwater calls produced by killer whales (Orcinus orca) in British Columbia
,”
Can. Data Rep. Fish. Aquat. Sci.
633
,
1
165
.
22.
Ford
,
J. K.
(
1989
). “
Acoustic behaviour of resident killer whales (Orcinus orca) off Vancouver Island, British Columbia
,”
Can. J. Zool.
67
,
727
745
.
23.
Ford
,
J. K. B.
(
1984
). “
Call traditions and dialects of killer whales (Orcinus orca) in British Columbia
,” Ph.D. dissertation,
University of British Columbia
,
Vancouver, BC
.
24.
Ford
,
J. K. B.
(
1991
). “
Vocal traditions among resident killer whales (Orcinus orca) in coastal waters of British Colombia
,”
Can. J. Zool.
69
,
1454
1483
.
25.
Ford
,
J. K.
,
Ellis
,
G. M.
, and
Balcomb
,
K. C.
(
1994
).
Killer Whales: The Natural History and Genealogy of Orcinus Orca in British Columbia and Washington State
(
University of British Columbia Press
,
Vancouver, BC
).
26.
Ford
,
J. K.
, and
Ellis
,
G. M.
(
1999
).
Transients: Mammal-Hunting Killer Whales of British Columbia, Washington, and Southeastern Alaska
(
University of British Columbia Press
,
Vancouver, BC
).
27.
Ford
,
J.
, and
Pilkington
,
J.
(
2019
). (personal communication).
28.
Ford
,
J. K. B.
,
Stredulinsky
,
E. H.
,
Ellis
,
G. M.
,
Durban
,
J. W.
, and
Pilkington
,
J. F.
(
2014
). “
Offshore killer whales in Canadian Pacific waters: Distribution, seasonality, foraging ecology, population status and potential for recovery
,” Technical Report, Canadian Science Advisory Secretariat (CSAS), Ottawa, ON.
29.
Frost
,
K. J.
,
Russell
,
R. B.
, and
Lowry
,
L. F.
(
1992
). “
Killer whales, Orcinus orca, in the southeastern Bering Sea: Recent sightings and predation on other marine mammals
,”
Mar. Mammal Sci.
8
,
110
119
.
30.
Gassmann
,
M.
,
Elizabeth Henderson
,
E.
,
Wiggins
,
S. M.
,
Roch
,
M. A.
, and
Hildebrand
,
J. A.
(
2013
). “
Offshore killer whale tracking using multiple hydrophone arrays
,”
J. Acoust. Soc. Am.
134
,
3513
3521
.
31.
George
,
J. C.
, and
Suydam
,
R.
(
1998
). “
Observations of killer whale (Orcinus orca) predation in the northeastern Chukchi and western Beaufort Seas
,”
Mar. Mammal Sci.
14
,
330
332
.
32.
Grebmeier
,
J. M.
,
Bluhm
,
B. A.
,
Cooper
,
L. W.
,
Danielson
,
S. L.
,
Arrigo
,
K. R.
,
Blanchard
,
A. L.
,
Clarke
,
J. T.
,
Day
,
R. H.
,
Frey
,
K. E.
,
Gradinger
,
R. R.
,
Kędra
,
M.
,
Konar
,
B.
,
Kuletz
,
K. J.
,
Lee
,
S. H.
,
Lovvorn
,
J. R.
,
Norcross
,
B. L.
, and
Okkonen
,
S. R.
(
2015
). “
Ecosystem characteristics and processes facilitating persistent macrobenthic biomass hotspots and associated benthivory in the Pacific Arctic
,”
Prog. Oceanogr.
136
,
92
114
.
33.
Grebmeier
,
J. M.
,
Cooper
,
L. W.
,
Feder
,
H. M.
, and
Sirenko
,
B. I.
(
2006
). “
Ecosystem dynamics of the Pacific-influenced northern Bering and Chukchi Seas in the Amerasian Arctic
,”
Prog. Oceanogr.
71
,
331
361
.
34.
Hannay
,
D. E.
,
Delarue
,
J.
,
Mouy
,
X.
,
Martin
,
B. S.
,
Leary
,
D.
,
Oswald
,
J. N.
, and
Vallarta
,
J.
(
2013
). “
Marine mammal acoustic detections in the northeastern Chukchi Sea,” September 2007–July 2011
,”
Cont. Shelf Res.
67
,
127
146
.
35.
Higdon
,
J. W.
, and
Ferguson
,
S. H.
(
2009
). “
Loss of Arctic sea ice causing punctuated change in sightings of killer whales (Orcinus orca) over the past century
,”
Ecol. Appl.
19
,
1365
1375
.
36.
Higdon
,
J. W.
, and
Ferguson
,
S. H.
(
2010
). “
Past, present, and future for bowhead whales (Balaena mysticetus) in northwest Hudson Bay
,” in
A Little Less Arctic: Top Predators in the World's Largest Northern Inland Sea, Hudson Bay
, edited by
S. H.
Ferguson
,
L. L.
Loseto
, and
M. L.
Mallory
(
Springer
,
New York
), pp.
159
177
.
37.
Huntington
,
H. P.
(
1989
). “
The Alaska Eskimo Whaling Commission: Effective local management of a subsistence resource
,” Ph.D. dissertation,
Scott Polar Research Institute
,
University of Cambridge, UK
.
38.
Huntington
,
H. P.
, and
Quakenbush
,
L. T.
(
2013
). “
Traditional knowledge regarding walrus near Point Hope, Alaska
,”
Report to Native Village of Point Hope and Bureau of Ocean Energy Management for Contract No. M09PC00027
,
9
pp.
39.
Ljungblad
,
D. K.
, and
Moore
,
S. E.
(
1983
). “
Killer whales (Orcinus orca) chasing gray whales (Eschrichtius robustus) in the northern Bering Sea
,”
Arctic
36
,
361
364
.
40.
Lowry
,
L. F.
,
Nelson
,
R. R.
, and
Frost
,
K. J.
(
1987
). “
Observations of killer whales, Orcinus orca, in western Alaska: Sightings, strandings, and predation on other marine mammals
,”
Can. Field-Nat.
101
,
6
12
.
41.
Madrigal
,
B. C.
(
2019
). “
Determining ecotype presence and the call repertoire of killer whales (Orcinus orca) recorded near Point Hope, Alaska in the southeastern Chukchi Sea
,”
M.Sc. thesis
,
California State Monterey Bay
,
Monterey Bay, CA
.
42.
Marquette
,
W. M.
, and
Braham
,
H. W.
(
1982
). “
Gray whale distribution and catch by Alaskan Eskimos: A replacement for the bowhead whale?
,”
Arctic
35
,
386
394
.
43.
MathWorks, Inc.
(
2019
).
Signal Processing Toolbox for Use with MATLAB: Reference R2019b
(
The MathWorks
,
Natick, MA
).
44.
Moore
,
S. E.
,
Grebmeier
,
J. M.
, and
Davies
,
J. R.
(
2003
). “
Gray whale distribution relative to forage habitat in the northern Bering Sea: Current conditions and retrospective summary
,”
Can. J. Zool.
81
,
734
742
.
45.
Morin
,
P. A.
,
LeDuc
,
R. G.
,
Robertson
,
K. M.
,
Hedrick
,
N. M.
,
Perrin
,
W. F.
,
Etnier
,
M.
,
Wade
,
P.
, and
Taylor
,
B. L.
(
2006
). “
Genetic analysis of killer whale (Orcinus orca) historical bone and tooth samples to identify western US ecotypes
,”
Mar. Mammal Sci.
22
,
897
909
.
46.
Morton
,
A. B.
(
1990
). “
A quantitative comparison of the behaviour of resident and transient forms of the killer whale off the central British Columbia coast
,”
Rep. Int. Whal. Comm. (Spec. Issue)
12
,
245
248
.
47.
Muto
,
M. M.
,
Helker
,
V. T.
,
Angliss
,
R. P.
,
Boveng
,
P. L.
,
Breiwick
,
J. M.
,
Cameron
,
M. F.
,
Clapham
,
P. J.
,
Dahle
,
S. P.
,
Dalheim
,
M. E.
,
Fadely
,
B. S.
,
Ferguson
,
M. C.
,
Fritz
,
L. W.
,
Hobbs
,
R. C.
,
Ivashchenko
,
Y. V.
,
Kennedy
,
A. S.
,
London
,
J. M.
,
Mizroch
,
S. A.
,
Ream
,
R. R.
,
Richmond
,
E. L.
,
Shelden
,
K. E. W.
,
Sweeney
,
K. L.
,
Towell
,
R. G.
,
Wade
,
P. R.
,
Waite
,
J. M.
, and
Zerbini
,
A. N.
(
2019
). “
Alaska marine mammal stock assessments, 2018
,”
NOAA Technical Memorandum NMFS-AFSC-393 (U.S. Department of Commerce, Washington, DC)
,
390
pp.
48.
Nachtigall
,
P. E.
, and
Moore
,
P. W.
(eds.) (
2012
).
Animal Sonar: Processes and Performance
(
Springer Science and Business Media
,
New York
).
49.
Oswald
,
J. N.
, and
Oswald
,
M.
(
2013
). “
ROCCA (Real-time Odontocete Call Classification Algorithm) user's manual
,” prepared for Naval Facilities Engineering Command Atlantic, Norfolk, Virginia under HDR Environmental, Operations and Construction, Inc., Contract No. CON005-4394-009, Subproject 164744, Task Order 03, Agreement No. 105067 (
Bio-Waves, Inc
.,
Encinitas, CA
).
50.
Reeves
,
R. R.
(
2002
). “
The origins and character of ‘aboriginal subsistence’ whaling: A global review
,”
Mamm. Rev.
32
,
71
106
.
51.
Rehn
,
N.
,
Filatova
,
O. A.
,
Durban
,
J. W.
, and
Foote
,
A. D.
(
2011
). “
Cross-cultural and cross-ecotype production of a killer whale ‘excitement’ call suggests universality
,”
Naturwissenschaften
98
,
1
6
.
52.
Reinhart
,
N. R.
,
Ferguson
,
S. H.
,
Koski
,
W. R.
,
Higdon
,
J. W.
,
LeBlanc
,
B.
,
Tervo
,
O.
, and
Jepson
,
P. D.
(
2013
). “
Occurrence of killer whale Orcinus orca rake marks on Eastern Canada-West Greenland bowhead whales Balaena mysticetus
,”
Polar Biol.
36
,
1133
1146
.
53.
Riesch
,
R.
,
Ford
,
J. K.
, and
Thomsen
,
F.
(
2008
). “
Whistle sequences in wild killer whales (Orcinus orca)
,”
J. Acoust. Soc. Am.
124
,
1822
1829
.
54.
Saulitis
,
E. L.
,
Matkin
,
C. O.
, and
Fay
,
F. H.
(
2005
). “
Vocal repertoire and acoustic behavior of the isolated AT1 killer whale subpopulation in southern Alaska
,”
Can. J. Zool.
83
,
1015
1029
.
55.
Sharpe
,
D. L.
,
Castellote
,
M.
,
Wade
,
P. R.
, and
Cornick
,
L. A.
(
2017
). “
Call types of Bigg's killer whales (Orcinus orca) in western Alaska: Using vocal dialects to assess population structure
,”
Bioacoustics
28
,
74
99
.
56.
Simonis
,
A. E.
,
Baumann-Pickering
,
S.
,
Oleson
,
E.
,
Melcón
,
M. L.
,
Gassmann
,
M.
,
Wiggins
,
S. M.
, and
Hildebrand
,
J. A.
(
2012
). “
High-frequency modulated signals of killer whales (Orcinus orca) in the North Pacific
,”
J. Acoust. Soc. Am.
131
,
EL295
EL301
.
57.
Springer
,
A. M.
,
McRoy
,
C. P.
, and
Flint
,
M. V.
(
1996
). “
The Bering Sea Green Belt: Shelf‐edge processes and ecosystem production
,”
Fish. Oceanogr.
5
,
205
223
.
58.
Stafford
,
K. M.
(
2019
). “
Increasing detections of killer whales (Orcinus orca), in the Pacific Arctic
,”
Mar. Mammal Sci.
35
,
696
706
.
59.
Thomsen
,
F.
,
Franck
,
D.
, and
Ford
,
J. K. B.
(
2001
). “
Characteristics of whistles from the acoustic repertoire of resident killer whales (Orcinus orca) off Vancouver Island, British Columbia
,”
J. Acoust. Soc. Am.
109
,
1240
1246
.
60.
Vate Brattström
,
L.
,
Mocklin
J. A.
,
Crance
J. L.
, and
Friday
,
N. A.
(ed.) (
2019
). “
Arctic Whale Ecology Study (ARCWEST): Use of the Chukchi Sea by endangered Baleen and other whales (westward extension of the BOWFEST)
,”
Final Report of the Arctic Whale Ecology Study (ARCWEST), OCS Study BOEM 2018-022
,
Marine Mammal Laboratory, Alaska Fisheries Science Center, NMFS, NOAA
,
Seattle, WA
.
61.
Watkins
,
W. A.
(
1967
). “
The harmonic interval: Fact or artifact in spectral analysis of pulse trains
,” in
Marine Bio-Acoustics
, edited by
W. N.
Tavolga
(
Pergamon
,
New York
), pp.
15
42
.
62.
Williams
,
T. M.
,
Estes
,
J. A.
,
Doak
,
D. F.
, and
Springer
,
A. M.
(
2004
). “
Killer appetites: Assessing the role of predators in ecological communities
,”
Ecology
85
,
3373
3384
.
63.
Willoughby
,
A. L.
,
Ferguson
,
M. C.
,
Stimmelmayr
,
R.
,
Clarke
,
J. T.
, and
Brower
,
A. A.
(
2020
). “
Bowhead whale (Balaena mysticetus) and killer whale (Orcinus orca) co-occurrence in the US Pacific Arctic, 2009–2018: Evidence from bowhead whale carcasses
,”
Polar Biol.
43
,
1669
1679
.
64.
Yurk
,
H.
,
Barrett-Lennard
,
L.
,
Ford
,
J. K. B.
, and
Matkin
,
C. O.
(
2002
). “
Cultural transmission within maternal lineages: Vocal clans in resident killer whales in southern Alaska
,”
Anim. Behav.
63
,
1103
1119
.

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