ICR

No. 3
December 2019

TECHNICAL REPORTS OF THE
INSTITUTE OF CETACEAN RESEARCH
TEREP-ICR is published annually by the InsƟtute of Cetacean Research.
ISSN: 2433-6084
Copyright © 2019, The InsƟtute of Cetacean Research (ICR).

CitaƟonEnƟre issue:InsƟtute of Cetacean Research. 2019. Technical Reports of the InsƟtute of Cetacean Research (TEREP-ICR) No. 3. The InsƟtute of Cetacean Research, Tokyo, Japan, 82 pp.
Individual reports:‘Author Name’. 2019. ‘Report Ɵtle’. Technical Reports of the InsƟtute of Cetacean Research (TEREPICR) No. 3: ‘pp’-’pp’.

Editorial correspondence should be sent to:
Editor, TEREP-ICR
The InsƟtute of Cetacean Research,
4-5 Toyomi-cho, Chuo-ku, Tokyo 104-0055, Japan
Phone: +81(3) 3536 6521
Fax: +81(3) 3536 6522
E-mail: webmaster@icrwhale.org
TEREP-ICR is available online at www.icrwhale.org/TEREP-ICR.html

Cover photo: Measuring the body of an AntarcƟc minke whale aboard a research base ship in the
AntarcƟc (top); cetacean sighƟng acƟviƟes in the AntarcƟc (middle); deployment of a ConducƟvity
Temperature Depth (CTD) proĮler in the AntarcƟc (below).
Copyright © 2019, The InsƟtute of Cetacean Research (ICR).
TECHNICAL REPORTS OF THE
INSTITUTE OF CETACEAN RESEARCHTEREP-ICR
No. 3

The Institute of Cetacean Research (ICR)
Tokyo, 2019

Technical Reports of the Institute of Cetacean Research (2019)

p. i

Obituary
This issue of TEREP-ICR is respectfully dedicated to Dr. Seiji Ohsumi, who died on 2 November 2019 at the age of 89 years
old, to his long time devotion to cetacean research and important scientiﬁc contributions to the biology, conservationand management of this group of animals. Dr. Ohsumi was Director General of the Institute of Cetacean Research in the
period 1995–2003, and at the time of his death was Honorary Scientiﬁc Adviser of the institute. Dr. Ohsumi was one of
the leading members of the Scientiﬁc Committee of the International Whaling Commission between the 1960ʼs and the2010ʼs. We will miss him deeply.

iTechnical Reports of the Institute of Cetacean Research (2019)

p. iii

Foreword
It is a pleasure for me to introduce the third issue of the Technical Reports of the Institute of Cetacean Research (TEREPICR-3). At the outset I would like to inform that, as an eﬀect of the change in the whaling policy of the Government ofJapan, the whale research programs under special scientiﬁc permit, NEWREP-A in the Antarctic and NEWREP-NP in thewestern North Paciﬁc, ceased on 30 June 2019. As explained in earlier issues, research under these programs was themain and ﬁrst priority of the ICR. From now on, Japan will conduct whale research programs based on non-lethal methods in both the North Paciﬁc and the Antarctic Oceans. In addition, collection of biological samples and data will continue based on whales caught for commercial purposes in Japanʼs territorial waters and Exclusive Economic Zone. The
ICR will have an important role in designing and implementing new research programs, and our scientists will continue
analyzing samples and data collected from previous and new research programs. Consistent with its stated objectives,
TEREP-ICR will continue describing and reporting on the process, progress, and results of technical or scientiﬁc research,or the state of technical or scientiﬁc research programs conducted by the ICR.
Similar to TEREP-ICR-1, TEREP-ICR-2 was widely distributed to approximately 120 individual scientists from Japan and30 foreign countries. It was also distributed to approximately 160 research institutions (including universities, research
institutes, public libraries, museums and aquariums), both in Japan and foreign countries. As a result of disseminating information on ICRʼs research activities through the TEREP-ICR, an increasing number of international scientists are showing interest in conducting research in collaboration with the ICR. Based on this, I believe that TEREP-ICR are contributing
to achieve its stated objectives.
I sincerely hope that this third issue of the TEREP-ICR will continue contributing to an increased understanding of thetechnical and research activities conducted by the ICR among the national and international scientiﬁc community.
Dr. Yoshihiro Fujise
Director General ICRTokyo, December 2019iii

Technical Reports of the Institute of Cetacean Research (2019)

p. v

Editorial
Welcome to the third issue of the Technical Reports of the Institute of Cetacean Research (TEREP-ICR-3).
This third issue contains seven technical reports and one commentary article. The ﬁrst report summarizes the resultsof research on assessment and management of Antarctic minke whales. The second report shows the progress of theresearch on age estimation in Antarctic minke whale based on aspartic acid racemization. The third report explains theimportance of g(0) for estimating abundance of large whales in the Antarctic. The fourth report summarizes the technical aspects of ICRʼs oceanographic and krill surveys in the Antarctic. The next two reports in this issue deal with researchin the North Paciﬁc. The ﬁrst one summarizes the information on population genetic structure of the North Paciﬁc sei
whale, which is of importance for management purposes. The second one summarizes the information on spatial andtemporal distribution of large whales in the western North Paciﬁc, emphasizing the importance of long-term monitoring
research programs. The technical report note explains the platform and equipment used during the ICRʼs satellite tracking experiments on large whales.
The commentary article deals with the issue of Japanʼs withdrawal from the International Whaling Commission andthe implications of this for the whale research conducted by the ICR.
This third TEREP-ICR issue also includes sections to outline the contribution of ICR scientists to national and international meetings in 2019 as well as their contribution in terms of peer-reviewed publications up to December 2019.
I hope you will ﬁnd this third issue informative and useful.
Dr. Luis A. Pastene
Editor TEREP-ICR
Tokyo, December 2019v

Technical Reports of the Institute of Cetacean Research (2019)

p. viiContents
Obituaryi

Forewordiii

Editorialv

Contents

vii

Technical Reports
Tamura, T., Matsuoka, K. and Pastene, L.A. What do we know about whales and the ecosystem in the
Indo-Paciﬁc region of the Antarctic? Part 1: Summary of results on assessment and managementof Antarctic minke whales

1

Yasunaga, G. Age estimation of Antarctic minke whales based on aspartic acid racemization:technical development

9

Takahashi, M. A note on g(0) estimates derived from vessel-based sighting surveys

14

Wada, A. Dedicated whale sighting vessels as a platform for krill and oceanographic research in the
21
Indo-Paciﬁc region of the Antarctic
Taguchi, M. Genetic study of stock structure in North Paciﬁc sei whales

32

Matsuoka, K. and Hakamada, T. Distribution of blue, ﬁn, humpback and North Paciﬁc right whales in
the western North Paciﬁc based on JARPN and JARPNII surveys (1994–2014)41

Technical Reports-Note
Konishi, K. and Isoda, T. The platform and equipment for satellite-monitored tagging experiments in
NEWREP-A and NEWREP-NP
52

Commentary
Pastene, L.A. Withdrawal of Japan from the International Convention for the Regulation of Whaling:
implications for the whale research conducted by the Institute of Cetacean Research
55

International meetings

59

National meetings

63

Peer-reviewed publications

65

vii

Technical Reports of the Institute of Cetacean Research (2019)

pp. 1–8

Technical Report (not peer reviewed)

What do we know about whales and the ecosystem in the Indo-Paciﬁcregion of the Antarctic? Part 1:
Summary of results on assessment and management of Antarctic
minke whales
Tsutomu Tamura*, Koji Matsuoka and Luis A. Pastene
Institute of Cetacean Research, 4–5 Toyomi-cho, Chuo-ku, Tokyo 104–0055, Japan*Contact e-mail: tamura@cetacean.jp

ABSTRACTThe Institute of Cetacean Research has conducted whale research under special scientiﬁc permit in the Antarctic since the austral summer season of 1987/88. The research was conducted systematically under diﬀerent research programs such as JARPA and JARPAII, and more recently, under the NEWREP-A. These research
programs employed both lethal and non-lethal methods. NEWREP-A ceased after the 2018/19 austral summer
season as an eﬀect of Japanʼs decision to withdraw from the International Whaling Commission and start
commercial whaling within its Exclusive Economic Zone. This paper summarizes the most relevant outputs
from the Japanese research programs under special scientiﬁc permit in the Indo-Paciﬁc region of the Antarctic
related to the assessment and management of Antarctic minke whales.

INTRODUCTION
Japan conducted systematic research on whales and theAntarctic ecosystem for more than 30 years. The ﬁrst
research program was the Japanese Research Program
under Special Permit in the Antarctic (JARPA), which was
followed by JARPAII and subsequently by the New Scientiﬁc Whale Research Program in the Antarctic Ocean(NEWREP-A). The Institute of Cetacean Research (ICR)
has been the institution in charge of designing and implementing those research programs. Tamura et al. (2017)provided details on the objectives, sampling and analytical methodology of these three research programs.
Several international review workshops (e.g. IWC, 2015)
discussed and evaluated the large amount of data andresults from those research programs.
As an eﬀect of the change in the whaling policy of theGovernment of Japan, NEWREP-A ceased from 1 July
2019. From now on, Japan will conduct whale researchin the Antarctic based solely on non-lethal methods. At
this point, it was considered important to summarize theknowledge on whales and the Antarctic ecosystem accumulated so far by the Japanese whale research in the
Antarctic.
The objective of this paper was to summarize the most
relevant outputs from the Japanese research programs

under special scientiﬁc permit in the Indo-Paciﬁc regionof the Antarctic related to the assessment and management of Antarctic minke whales.

SURVEYS, DATA AND SAMPLES
Surveys were conducted in the Indo-Paciﬁc region of
the Antarctic, which correspond to the International
Whaling Commission (IWC)ʼs management Areas III, IV,
V and VI (Figure 1). Survey and sampling methodologiesof the Japanese whale research programs in the Antarctic were explained in Pastene et al. (2014) and Tamura
et al. (2017). A list of data and samples collected by theJapanese whale research programs in the Antarctic wasavailable from the IWC (2015).
The most relevant research outputs for assessmentand management (i.e. taxonomy/stock structure, abundance and biological parameters) of Antarctic minke
whales are presented in the next section.

MAIN RESEARCH OUTPUTS
Taxonomical aspects
Until relatively recently, only one species of minke whale
was thought to exist: Balaenoptera acutorostrata Lacèpéde, 1804. However, Rice (1998) reviewed morphological (e.g. Williamson, 1959; van Utrecht and van der
Spoel, 1962; Kasuya and Ichihara, 1965; Omura, 1975;1

Technical Reports of the Institute of Cetacean Research (2019)

Figure 1.

Research area of the JARPA, JARPAII and NEWREP-A in the Indo-Paciﬁc region of the Antarctic.

Figure 2.

External appearance of Antarctic minke (above) and dwarf minke (below) whales.

Best, 1985) and genetic (e.g. Wada et al., 1991; Arnason
et al., 1993; Pastene et al., 1994) data collected fromextant minke whale populations and re-speciﬁed two
species, the Antarctic minke whale B. bonaerensis Burmeister, 1867, which is restricted to the Southern Hemisphere, and the common minke whale B. acutorostrata
Lacèpéde, 1804, which is distributed globally.
In the Southern Hemisphere the common minke whale
is known as ʻdiminutiveʼ or ʻdwarfʼ minke whale (Best,
1985; Arnold et al., 1987). Currently, the dwarf minke
whale is considered an un-named sub-species of B.
acutorostrata. A large amount of biological and genetic
information was obtained from 16 dwarf minke whalescaught by earlier JARPA surveys in the Indo-Paciﬁc regionof the Antarctic. Earlier genetic analyses based on thosesamples and mitochondrial DNA (mtDNA) showed thatdwarf and North Paciﬁc minke whales were more similar to each other than they were to the Antarctic minke
whale (Wada et al., 1991; Pastene et al., 1994).
2

Kato and Fujise (2000) reported on the morphology,
growth and life history of dwarf minke whales based on
16 animals sampled by JARPA in the Indo-Paciﬁc regionof the Antarctic. Results of their analyses conﬁrmed several of the morphological and morphometric characters
reported previously, and the striking diﬀerences with
the Antarctic minke whale. The mean body length at
physical maturity was estimated at 7.0 m and 6.6 m forfemales and males, respectively. The age and length atsexual maturity in females was 7–10 years and 6.0–6.5 m,
respectively. Furthermore, the authors stated that theconception of the dwarf minke whale is highly concentrated in mid-winter. Some additional morphologicaland morphometric analyses of minke whales worldwide,
including dwarf minke whales, were conducted by Nakamura et al. (2014) and Kato et al. (2015).
On the basis of the morphological diﬀerences documented by Best (1985) and Arnold et al. (1987) andgenetic diﬀerences (Wada et al., 1991) the IWC Scien-

What do we know about whales and the ecosystem in the Indo-Pacific region of the Antarctic? Part 1

tiﬁc Committee (IWC SC) recognized the existence of two
southern minke whales and agreed that the two minke
whales in the Southern Hemisphere should deﬁnitively
be considered separately for management purposes(IWC, 1991). In 1993, after examining the genetic information provided by Pastene et al. (1994), the IWC SC
recommended the inclusion of the dwarf minke whalein the Schedule, so that catch limits for Antarctic minke
whales recognise the distinction between the two southern minke whales (IWC, 1994).
In 2000, the IWC SC again recognised the two species but deferred a decision on other nominal taxa until
the completion of a worldwide review of genetic andnon-genetics information for minke whales (IWC, 2001).
Subsequent worldwide genetic analyses of minke whales
provided further evidence for the separation of the two
species, B. bonaerensis and B. acutorostrata, and at least
three sub-species of the common minke whale as recognized by Rice (1998) using mtDNA sequences (Pastene
et al., 2010) and microsatellite DNA (Glover et al., 2013).
While additional genetic and morphological/morphometric studies are required to further elucidate the taxonomic status within B. acutorostrata, including that of thedwarf minke whale, there is agreement on the taxonomic
status of B. bonaerensis. Figure 2 shows the external
morphological appearance of Antarctic minke and dwarf
minke whales.
Stock structure of the Antarctic minke whale
Detailed information on stock structure of the Antarctic
minke whale was provided by Taguchi et al. (2017). The
main ﬁndings are summarized here.
The primary data sources for studies of stock structure in this species were from the JARPA and JARPAII
programmes, both of which had stock identity as one of
their objectives. Studies based upon these samples have
proved to be more useful than those from the commercial period, given the wider geographical coverage andthe more random sampling design. In contrast, the commercial whaling samples were taken mainly from areas ofhigh density near the ice-edge (Pastene, 2006). Initially,
the JARPA genetic studies on stock structure were basedon mtDNA Restriction Fragment Length Polymorphism(RFLP), and considerable genetic heterogeneity in Areas
IV and V was found (Pastene et al., 1993; 1996).
Consideration of a suite of information from mtDNA
and microsatellite DNA (Pastene et al., 2006), morphometrics for 10 external measurements (Fujise, 1995;
Hakamada, 2006) and mean length at physical maturity(Bando et al., 2006) led to the conclusion that Antarctic

minke whales in the feeding grounds between Areas
IIIE and VIW do not comprise a single stock (IWC, 2008).
Rather, the results are consistent with the occurrenceof at least two genetic stocks in these feeding grounds,
which are probably related to the two proposed breedingareas in the eastern Indian Ocean and western South Paciﬁc (Kasamatsu et al., 1995). The following names havebeen proposed for these stocks: Eastern Indian Ocean
Stock (I-Stock) and Western South Paciﬁc Ocean Stock(P-Stock) (Pastene, 2006). The analyses of the JARPA dataalso suggested an area of transition in the region around150°–165°E, across which there is an as yet undetermined level and range of mixing (IWC, 2008).
Given additional data from JARPAII, the analysesof stock structure were reﬁned in two ways: the ﬁrst
involved additional laboratory work for additional
genetic markers, and the second involved modiﬁed
analytical measures. All the Antarctic minke whales
taken by JARPAII between 2005/06 and 2010/11 weresequenced for a 340 bp-segment of the control region of
the mtDNA (instead of the mtDNA RFLP used in JARPA),
and genotyped using 12 microsatellite loci (instead of
the six used in JARPA). Results of the heterogeneity test
for both markers showed statistically signiﬁcant genetic
diﬀerences between whales in the two sectors, western(35°–130°E) and eastern (165°E–145°W), conﬁrming that
diﬀerent stocks inhabit the Indian and Paciﬁc sectors of
the Antarctic (the I- and P-stocks). Microsatellite DNA
analyses showed more dispersal amongst males thanfemales and some degree of annual variation (Pastene
and Goto, 2016).
Schweder et al. (2011) developed an integrated approach for estimating longitudinal segregation of two
stocks using various sources of data: morphometric,
microsatellite and mtDNA data. This approach revealed
that the soft boundary (or transition area) suggested
previously could vary by year and sex. A joint likelihood
function was deﬁned to estimate mixing proportions
and apply statistical tests without assuming any baseline
populations. The approach was originally applied to the
JARPA data (Schweder et al., 2011) and subsequently to
JARPA and JARPAII data (Kitakado et al., 2014). The resultsof this approach conﬁrmed the occurrence of at least two
stocks (I and P) in the Indo Paciﬁc sector of the Antarctic.
Furthermore, the results indicated that the spatial distribution of the two stocks had soft boundaries in Area
IVE (100°–130°E) and VW (130°–165°E), which changes
by year. Results also suggested possible sex diﬀerencesin the pattern of distribution of the two stocks (Kitakado
et al., 2014).
3

Technical Reports of the Institute of Cetacean Research (2019)

Figure 3.

Hypothesis on stock structure of the Antarctic minke whale. The upper ﬁgure shows the encounter ratesof Antarctic minke whales in 10° squares of latitude and longitude in waters 0°–30°S during October(Kasamatsu et al., 1995). The high sighting densities in the eastern Indian Ocean and western South Paciﬁc
could correspond to breeding grounds of this species. At least two stocks (I- and P-stocks) occur in the research area of JARPA and JARPAII, which mix through a transition area. The transition area and the mixing
rate appears to change by year and sex (Pastene and Goto, 2016).

Consequently, the structure of Antarctic minke whale
in Areas IIIE to VIW appears to be more complex thanoriginally thought. In summary, the IWC SC agreed(IWC, 2008) that there are (at least) two stocks with awide mixing area that may change by year and sex. The
extent of the I-stock to the west of 35°E and that of Pstock to the east of 145°W cannot be investigated due toa lack of appropriate samples.
The identiﬁcation of spatial and temporal boundaries
of stocks has been important for the interpretation of
the biological parameters estimated of this species in the
Antarctic (i.e. Punt et al., 2014; Bando, 2017), and should
also be important for the interpretation of abundance
and abundance trends in the near future.
Figure 3 shows a schematic representation of the stock
structure hypothesis derived from diﬀerent analyses
based on JARPA and JARPAII data.
Abundance of Antarctic minke whales
Detailed information on abundance estimates of Antarc4

tic minke whales was provided by Hakamada and Matsuoka (2017). The main ﬁndings are summarized here.
Hakamada et al. (2013) estimated abundance andabundance trends of Antarctic minke whales in the Indian sector (Area IV) and Paciﬁc sector (Area V) based onJapanese dedicated sighting surveys (JARPA and JARPAII),
under the assumption of g(0)=1. Abundance estimates
for the Indian sector range from 16,562 (CV=0.542) in
1997/98 to 44,945 (CV=0.338) in 1999/00, while thosefor the Paciﬁc sector range from 74,144 (CV=0.329) in
2004/05 to 151,828 (CV=0.322) in 2002/03. Estimates of
the annual rates of increase in abundance are 1.8% with
a 95% CI of [−2.5%, 6.0%] for the Indian sector and 1.9%
with a 95% CI of [−3.0%, 6.9%] for the Paciﬁc sector.
Adjustments to allow for the g(0) being less than 1
were made by the application of a regression model, developed from the results of the Okamura–Kitakado (OK)method estimate of minke whale abundance from the
IDCR/SOWER surveys, which provides estimates of g(0)from the statistics of the minke whale school size distri-What do we know about whales and the ecosystem in the Indo-Pacific region of the Antarctic? Part 1

bution in a stratum. With this adjustment, abundance
estimates increased by an average of 32,333 (106%) for
the Indian sector and 89,245 (86%) for the Paciﬁc sector,
while the estimates of annual rates of increase and their
95% CIs changed slightly to 2.6% [−1.5%, 6.9%] for the Indian sector and 1.6% [−3.4%, 6.7%] for the Paciﬁc sector.
See Figure 4 for the abundance trends in the two sectors.
In 2012 the IWC SC agreed to a new best abundance
estimate for Antarctic minke whales in Antarctic open waters south of 60°S, based on IDCR/SOWER sighting data.
The estimates were 720,000 based on the sighting datacollected during the CPII (1985/86–1990/91) with 95% CI(512,000, 1,012,000), and 515,000 based on the sighting
data collected during the CPIII (1992/93–2003/04) with
95% CI (361,000, 733,000). No signiﬁcant statistical diﬀerences were found between the CPII and CPIII estimates(IWC, 2013).
The estimates in the Indian sector (Area IV) were55,237 (CV: 0.17) in CPII and 59,677 (CV: 0.34) in CPIII. In
the Paciﬁc sector (Area V) were 300,214 (CV: 0.13) in CPII
and 183,915 (CV: 0.11) in CPIII.
By considering the 95% CIs of the estimates it can besuggested that the stocks of Antarctic minke whales are

Figure 4.

broadly stable with at most a slight decline, therefore theconclusion on trends is similar to that derived from JARPA
and JARPAII data in Areas IV and V.
Abundance of Antarctic minke whales should be interpreted in the near future in the context of additional
information on stock structure of the species in the IndoPaciﬁc region of the Antarctic.
Biological parameters of Antarctic minke whale
Detailed information on biological parameter estimatesof Antarctic minkes whale was provided by Bando (2017).
The main ﬁndings are summarized here.
Estimates of biological parameters of Antarctic minke
whales based on samples obtained during the JARPA, aresummarized in Table 1 (IWC, 2008; Bando, 2017).
The grouping of samples for the estimates of biologicalparameters considered the information on stock structure summarized above.
Age dependent natural mortality was estimated fromthe Statistical Catch-at-Age (SCAA) model. The pattern
was similar for the I and P stocks with natural mortality
being higher in young and old animals. It was calculated
as 0.048 (for age=15) to 0.107 (for age=35) for the I-

The best-case estimates of annual abundance of Antarctic minke whale in the Indian sector (Area IV) andPaciﬁc sector (Area V) together with their 95% CIs. The IDCR/SOWER estimates for a common northernboundary for CPII and CPIII are shown by the open triangles. Conﬁdence intervals include allowance for
additional variance. The dashed curves indicate the 95% CIs for the exponential model (after Hakamada
et al., 2013).

Table 1
Summary of biological parameters of Antarctic minke whales estimated according to one stock structure hypothesis(after IWC, 2008).

5

Technical Reports of the Institute of Cetacean Research (2019)

Figure 5.

Time-trajectories of total (1+) population size (upper panels), age-speciﬁc natural mortality (center panels), and total (1+) population size relative to carrying capacity (lower panels) for three ways to model natural mortality (the Siler model, autoregressive and piecewise linear) of two stocks of Antarctic minke whale(from Punt et al., 2014). Biological data obtained from both JARPA and JARPAII were used in the SCAA.

stock and 0.046 (for age=15) to 0.103 (for age=35) forP-stock (Figure 5) (Punt et al., 2014). Time-trajectories
derived from SCAA showed that total population size of
the Antarctic minke whale increased until 1970ʼs andthen declined until 2000ʼs for both stocks (Figure 5) (Puntet al., 2014).

CONCLUSIONSThe Japanese whale research programs under special
permit have provided important information on stock
structure, biological parameters and abundance of Antarctic minke whales in the Indo-Paciﬁc region of the Antarctic. Such information is key for the assessment of thespecies and the application of management procedures
such as the IWCʼs Revised Management Procedure (RMP)
in the future. Continuation of the systematic monitoringof the stocks of Antarctic minke whales is recommended.

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growth and life history with some analyses on morphometric variation among the diﬀerent forms and regions. Paper
SC/52/OS3 presented to the IWC Scientiﬁc Committee,
June 2000 (unpublished). 30 pp. [Available from the IWC
Secretariat].
Kato, H., Fujise, Y., Nakamura, G., Pastene, L.A., Hakamada, T. andBest, P.B. 2015. Marked Morphological and MorphometricDiﬀerentiation between Dwarf minke and Antarctic andCommon minke whales. 21st Biennial Conference on the
biology of marine mammals. Society of Marine Mammalogy.
13–18 December 2015. San Francisco (Abstract).
Kitakado, T., Schweder, T., Kanda, N., Pastene, L.A. and Walløe, L.
2014. Dynamic population segregation by genetics and morphometrics in Antarctic minke whales (SC/F14/J29rev). Paper
SC/65b/IA13 presented to the IWC Scientiﬁc Committee,
May 2014 (unpublished). 25 pp. [Available from the IWC
Secretariat].
Nakamura, G., Kadowaki, I., Nagatsuka, S., Fujise, Y., Kishiro,
T. and Kato, H. 2014. Variation in a color pattern of whitepatch on the ﬂippers of North Paciﬁc common minke whales:
Potential application for their interoceanic diﬀerence. La mer
52: 31–47.
Omura, H., 1975. Osteological study of the minke whale fromthe Antarctic. Sci. Rep. Whales Res. Inst. 27: 1–36.
Pastene, L.A., Kobayashi, T., Fujise, Y. and Numachi, K. 1993.
Mitochondrial DNA diﬀerentiation in Antarctic minke whales.
Rep. int. Whal. Commn 43: 349–355.
Pastene, L.A., Fujise, Y. and Numachi, K. 1994. Diﬀerentiationof mitochondrial DNA between ordinary and dwarf forms ofminke whale. Rep. int. Whal. Commn 44: 277–281.
Pastene, L.A., Goto, M., Itoh, S. and Numachi, K. 1996. Spatial
and temporal patterns of mitochondrial DNA variation inminke whale from Antarctic Areas IV and V. Rep. int. Whal.
Commn 46: 305–314.
Pastene, L.A. 2006. What do we know about the stock structure of the Antarctic minke whale? A summary of studies
and hypotheses. Paper SC/D06/J12 presented to the Expert
Workshop to Review the Japanese JARPAII Special Permit
Research Programme, 4–8 December 2006 (unpublished). 24
pp. [Available from the IWC Secretariat].
Pastene, L.A., Goto, M. and Kanda, N. 2006. Genetic analysis
on stock structure in the Antarctic minke whales from the
JARPA research area based on mitochondrial DNA and microsatellites. Paper SC/D06/J9 presented to the Intersessional
Workshop to Review Data and Results from Special Permit
Research on Minke Whales in the Antarctic, Tokyo December
2006 (unpublished). 22 pp. [Available from the IWC
Secretariat].
Pastene, L.A., Acevedo, J., Goto, M., Zerbini, A.N., Acuna, P.
and Aguayo-Lobo, A. 2010. Population structure and possible migratory links of common minke whales, Balaenoptera
acutorostrata, in the Southern Hemisphere. Conserv. Genet.

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Pastene, L.A., Fujise, Y. and Hatanaka, H. 2014. The Japanese
Whale Research Program under Special Permit in the
Antarctic—Phase II (JARPAII): origin, objectives, research
progress made in the period 2005/06–2010/2011 and relevance for management and conservation of whales andthe ecosystem. Paper SC/F14/J01 presented to the Expert
Workshop to Review the Japanese JARPAII Special Permit
Research Programme, February 2014 (unpublished). 76 pp.
[Available from the IWC Secretariat].
Pastene, L.A. and Goto, M. 2016. Genetic characterization andpopulation genetic structure of the Antarctic minke whale
Balaenoptera bonaerensis in the Indo-Paciﬁc region of theSouthern Ocean. Fish Sci 82: 873–886.
Punt, A.E., Hakamada, T., Bando, T. and Kitakado, T. 2014.
Assessment of Antarctic minke whales using statistical catchat-age analysis (SCAA). J. Cetacean Res. Manage. 14: 93–116.
Rice, D.W. 1998. Marine Mammals of the World: Systematics
and Distribution. Marine Mammal Science Special Publication
No.4. The Society of Marine Mammalogy. Lawrence, Kansas.
231 pp.
Schweder, T., Kitakado, T., Kanda, N., Pastene, L.A. and Walløe,

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L. 2011. Dynamic population segregation by genetics andmorphometrics in Antarctic minke whales. Paper SC/63/IA7
presented to the IWC Scientiﬁc Committee. May–June 2011
(unpublished). 20 pp. [Available from the IWC Secretariat].
Taguchi, M., Goto, M. and Pastene, L.A. 2017. What do weknow about the stock structure of Antarctic minke whalesin the Indo-Paciﬁc region of the Antarctic? A brief review ofmethodologies and research outputs. Technical Reports of
the Institute of Cetacean Research (TEREP-ICR) No. 1: 15–21.
Tamura, T., Matsuoka, K. and Pastene, L.A. 2017. An overview
of the research programs on large whales conducted by
the Institute of Cetacean Research. Technical Reports of theInstitute of Cetacean Research (TEREP-ICR) No. 1: 1–14.
van Utrecht, W.L. and van der Spoel, S. 1962. Observations
on a minke whale (Mammalia, Cetacea) from the Antarctic.
Zeitschrift fur Siiugetierkunde 27 (4): 217–221.
Wada, S., Kobayashi, T. and Numachi, K. 1991. Genetic variability and diﬀerentiation of mitochondrial DNA in minke whales.
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Technical Reports of the Institute of Cetacean Research (2019)

pp. 9–13

Technical Report (not peer reviewed)

Age estimation of Antarctic minke whales based on aspartic acidracemization: technical development
Genta Yasunaga*
Institute of Cetacean Research, 4–5 Toyomi-cho, Chuo-ku, Tokyo 104–0055, Japan*Contact e-mail: yasunaga@cetacean.jp

ABSTRACTAt present, examination of earplugs is the only practicable means to obtain age data at the annual scale inbaleen whales. It is the only method providing age data accurate enough for population-level analyses such as
the Statistical Catch-at-Age Analysis (SCAA) of Antarctic minke whales. Because there are a number of whales
sampled with unreadable earplugs, the feasibility of using other techniques for age determination is being
investigated by scientists at the Institute of Cetacean Research with the aim of determining the age of thosesamples where earplugs does not work. One of those techniques is based on enantiomers of aspartic acid in
eye lens, the aspartic acid racemization (AAR) technique. This paper presents a brief review of the technicaldevelopment of the AAR technique at the Institute of Cetacean Research, and the preliminary results of using
this technique for age determination of Antarctic minke whales.

INTRODUCTION
Age is one of the most important life history parameters
for assessment and management of marine living resources. In baleen whales, age has been determined using
a variety of methods such as examination of baleen plates(Nishiwaki, 1951; Zenitani and Kato, 2010), earplugs(Lockyer, 1984) and tympanic bulla (Christensen, 1995).
Counting of the growth layers deposited in the earplugs isthe most accepted technique for determining chronological age of baleen whales (Lockyer, 1984). Earplug-based
age determination has the advantages that it is time- andcost-eﬃcient, and the technique can be used on available historical samples; however, unreadable growthlayers form in some individuals baleen whales (Maeda
et al., 2013; George et al., 1999). In such cases alternative
methods of age determination are required.
Indices of chronological age of whales have beendeveloped using molecular approaches. For example
length of telomeres, nucleoprotein caps ﬂanking DNA(Olsen et al., 2012), and methylation levels at the C5
position of cytosine residues adjacent to guanidine
residues (Polanowski et al., 2014) were examined in relation to age using skin of humpback whales (Megaptera
novaeangliae) in the Gulf of Maine. The feasibility of the
DNA methylation technique to determine age in Antarctic
minke whales (Balaenoptera bonaerensis) has been evaluated by scientists at the Institute of Cetacean Research(ICR) (Goto and Inoue, 2018). Currently, these epigenetic
approaches face challenges such as measurement of indices error and whale speciﬁc biological processes, whichmakes it diﬃcult to interpret the age of whales.
Regarding biochemical approaches, the Advanced Glycation End (AGE) products was proposed as one of thepossible factors underlying the functioning of the biological clock for mammals (Severin et al., 2013), however norelationship was observed between AGE levels and age
in bowhead whales (Rosa, 2006). Another technique isbased on enantiomers of aspartic acid in eye lens, the aspartic acid racemization (AAR) technique, which is being
developed at the ICR.
This paper presents a brief review of the technicaldevelopment of the AAR technique at the ICR, and shows
preliminary results of using this technique for age determination of Antarctic minke whale.

PRINCIPLE OF THE AGE ESTIMATION BY THE
ASPARTIC ACID RACEMIZATION TECHNIQUE
The AAR technique for determining age is based on
temporal changes of the ratio of D and L-enantiomers
of aspartic acid in mammals (Helfman and Bada, 1975)(Figure 1). The technique is based on the principle that
D-aspartic acid accumulates logarithmically with age, andthe crystalline in the core of the lens has been conserved
chemically since it is formed at the fetus stage and ismetabolically inactive for all of the animalʼs life (Masters
9Technical Reports of the Institute of Cetacean Research (2019)

Figure 1.

Figure 2.

Scheme of racemization of aspartic acid.

Research area of JARPAII in the 2005/2006 and 2007/2008 austral summer seasons.

et al., 1977).
Masters et al. (1977) and Bada et al. (1980) proposedthat the racemization of amino acids follows a ﬁrst-orderreversible rate law, where the racemization equation is:

2kAsp ⋅ t = Log e [ (1+ D /L) / (1 − D /L) ]{}–Ln [1+( D /L)0 ] [1 − ( D /L)0 ] .

(1)A linear regression model is constructed using this expression, where D/L is the ratio of D- and L-aspartic acids,t is any given time during racemization, and the logarithmic term at t=0 describes the amount of D-aspartic acidformed at birth.

RESEARCH ON ASPARTIC ACID RACEMIZATION AT
THE INSTITUTE OF CETACEAN RESEARCHAt the ICR, the feasibility of using the AAR technique todetermine the age of Antarctic minke whales has been
investigated (see details in Yasunaga et al., 2017). The
JARPA and JARPAII research programs in the Antarctic
have provided suﬃcient biological information on thisspecies that makes assumptions and extrapolations of
key parameters used in this technique unnecessary. For
example kAsp and (D/L)0 in Eq. (1) can be determined by direct comparison with earplug-based estimated ages, and(D/L)0 can be estimated using available foetal samples.
10

Samples
Antarctic minke whales used in this study were sampled
in the Indo region of the Antarctic, which corresponds
to the International Whaling Commissionʼs (IWC)ʼs management Area IV (70°–130°E), south of 62°S (Figure 2).
Whales were sampled during the austral summer seasons
2005/2006 and 2007/2008 by JARPAII surveys.
At the ﬁeld, scientists collected the left eyeball from
20 foetuses and lens samples from 18 female Antarctic
minke whales. The samples were stored in polyethylenebags at −80°C until analysis.
Preparation of lens of Antarctic minke whale
Lenses of all samples (foetuses and females) were rinsed
ﬁrst with phosphate-buﬀered saline (Figure 3). Then
their outermost layers were removed with mucus, andthe cores were dissected out using a surgical knife. Approximately 10 mg of core samples were homogenizedwith 1 ml of tris-buﬀer (200mM Tris, 150mM NaCl, pH
8.0) using an ultrasonic homogenizer. The homogenate
was centrifuged at 15,000×g for 15 min at 4°C, and 100 µlof the supernatant was then desalted with acetone andair-dried. They were hydrolyzed in the gas-phase HCl(6N-HCl) for 7 h at 108°C (Pico Tag Work Stations, Waters,
Tokyo) (Figure 4). The hydrolysates were evaporated

Age estimation of Antarctic minke whales based on aspartic acid racemization

Figure 3.

Lens of Antarctic minke whale rinsed with phosphate buﬀer.

Figure 5.

Figure 4.

Hydrolysis of lens of Antarctic minke whale using
Pico Tag Work Stations (Waters, Tokyo).

under reduced pressure.
Laboratory procedures
The Asp D/L was determined using HPCL (Alliance®
HPLC systems e2696, Waters) with a Nova-Pak ODS
column (3.9 mm×300 mm, Waters) using ﬂuorescence
detection (344 nm excitation wavelength and 443 nm
emission wave length) (Figure 5). Elution was carriedout with an isocratic adsorption of 3% acetonitrile +3%
tetrahydrofuran/0.1M acetate buﬀer pH 6.0 at a ﬂow rateof 0.8 ml/min and column temperature of 23°C. Then,
70 µl of borate buﬀer (0.1M, pH 10.4), 5 µl of n-tertbutyloxycarbonyl-l-cysteine and 5 µl of o-phthalaldehyde
were successively added to 5 µl of the hydrolysate dissolved in 0.1 N-HCl. The measured Asp D/L was calibrated
against real ratios in the standard solutions and then it
was corrected for hydrolysis eﬀect under our laboratory
conditions, which was represented as (D/L)act.

HPCL system (Alliance® HPLC systems e2696,
Waters) used for ﬂuorescence detection.

Results
Table 1 shows (D/L)act and the age index calculated for the
18 female Antarctic minke whales. The (D/L)0 which is oneof two speciﬁc coeﬃcients of AAR, was determined using
lenses of foetuses at various developing stages because
their (D/L)act can be approximated to those at birth. However, precision of the (D/L)0, which is estimated using foetuses was unsatisfactory ((D/L)0 =0.0134; SE=3.78×10−4;
95% conﬁdential interval 0.0121–0.0147).
Taken together, the slope of the age estimation equation was examined for two cases. Figure 6 shows the relationships between the age indexes and earplug ages. The
single outlier at 40-years-old for which Cookʼs distanceexceeded 2 was eliminated in the ﬁrst regression analysis.
The two equations (cases) of age estimation are shown
below as Eq. (2) and Eq. (3). In Eq. (1) linear regression
analysis were re-performed to determine kAsp substituting (D/L)0 =0.0134 using dataset of the (D/L)act and theearplug ages in the 17 whales as follows:{}

Log e [1+ ( D /L)act ] [1 − ( D /L)act ]= 1.79 ×10−3 × earplug age (year) + 0.0268,∴ p < 0.001, r 2 = 0.890, kAsp = 8.94 ×10−4 ,SE (2kAsp ) = 1.52 ×10−4 .

(2)In Eq. (3) linear regression analysis was performed todetermine kAsp and (D/L)0 in Eq. (1) using dataset of the(D/L)act and the earplug ages in the 17 whales as follows:11

Technical Reports of the Institute of Cetacean Research (2019)
Table 1
The actual D/L ratios of aspartic acid in lens and AAR ages of Antarctic minke whales.
Sample No.

Sex

Earplug Age(D/L)actLoge[(1+D/L)/(1−D/L)]

05/06-AM348
05/06-AM349
05/06-AM352
05/06-AM361
05/06-AM372
05/06-AM382
05/06-AM386
05/06-AM398
05/06-AM488
05/06-AM498
05/06-AM517
05/06-AM539
05/06-AM565
05/06-AM592
05/06-AM603
05/06-AM615
05/06-AM630
05/06-AM634

F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F

14
21
9
26
40
7
8
7
4
4
3
1
2
4
6
7
5
3

0.02230.03280.02220.04320.043
0.01730.019
0.01640.01360.01510.01060.01240.01740.01690.01730.01670.01520.01250.0446
0.06560.04440.08650.086
0.03470.038
0.03290.02720.03020.02120.02490.03480.03370.0346
0.03330.03050.025

Age estimated by the AAR*
Age

SE

95% CI

10.6
19.8
10.6
28.9

1.5
2.2
1.5
2.9

8.1–14.2
16.1–25.0
8.2–14.2
24.2–35.7

6.3
7.8
5.6
3.1
4.4
0.5
2.1
6.4
5.9
6.3
5.8
4.5
2.2

1.2
1.3
1.2
1
1.1
0.8
0.9
1.2
1.2
1.2
1.2
1.1
0.9

4.4–9.1
5.6–10.8
3.7–8.2
1.4–5.3
2.6–6.8−0.9–2.3
0.5–4.1
4.4–9.1
4.0–8.6
4.3–9.1
3.8–8.5
2.8–7.0
0.7–4.2* Ages estimated by the AAR were derived from Eq. (3)Figure 6.

Relationship between age indexes, Loge {[1+(D/L)act]/[1−(D/L)act]}, and ages of earplugs of Antarctic minke
whales: open circle was excluded from simple
linear regression analysis as an outlier, and a solidand broken line is calculated by Eq. (2) and Eq. (3),respectively.

{}

Log e [1+ (D /L)act ] [1 − ( D /L)act ]= 2.30 ×10−3 × earplug age (year) + 0.0201,
2−3∴ p < 0.001, r = 0.918, kAsp = 1.15 ×10 ,SE (2kAsp ) = 1.71×10−4 , SE (intercept) = 1.72 ×10−3 . (3)Squared correlation coeﬃcient of the Eq. (3) was
higher than that of the Eq. (2), and the SE of 2kAsp andintercept of the Eq. (3) were lower than those of the Eq.
12

Figure 7.

Relationship between ages estimated by AAR andearplugs (averages and SEs estimated by bootstrap
simulation) in Antarctic minke whales.

(2). Therefore, Eq. (3) is considered more precise and accurate to estimate ages of whales than Eq. (2).
Finally, the standard errors were calculated for theages estimated by AAR. Ages estimated from Eq. (3) and(D/L)act in each whale, including their SEs and 95% conﬁdence intervals estimated by bootstrap simulation, areshown in Table 1. Figure 7 shows the relationships be-Age estimation of Antarctic minke whales based on aspartic acid racemization

tween ages estimated from earplugs, and ages (including
SEs and 95% conﬁdence intervals), estimated by the AAR.
The range of SEs of the AAR-based age estimates was 0.9
and 2.9 years, and they were within the 95% conﬁdence
interval, except for one case.

CONCLUSIONSThis study was successful in developing the AAR technique for the Antarctic minke whale. The application ofthis technique can complement the age estimation ofindividuals of this species based on earplug reading, especially for young animals with unreadable earplugs. A
few issues including bias due to cataracts require further
consideration in the future.

ACKNOWLEDGEMENTS
I would like to thank the captains, crews and scientists involved in the 2005/2006 and 2007/2008 JARPAII surveys.
Thanks are also due to Noriko Fujii (Research Reactor Institute, Kyoto University), for providing HCLP analysis, andTakeharu Bando (ICR) for earplug-based age data.

REFERENCES
Bada, J.L., Brown, S.E. and Masters, P.M. 1980. Age determination of marine mammals based on aspartic acid racemizationin the teeth and lens nucleus. Rep. int. Whal. Commn (special
issue) 3: 113–118.
Christensen, I. 1995. Interpretation of growth layers in periosteal zone of tympanic bulla from minke whales Balaenoptera
acutorostrata. pp. 413–423. In: A.S. Brix, L. Walløe and Ø.
Ulltang (eds.) Whales, seals, ﬁsh and man. Elsevier Science,
Amsterdam. 717 pp.
George, J.C., Bada, J., Zeh, J., Scott, L., Brown, S.E., OʼHara, T.
and Suydam, R. 1999. Age and growth estimates of bowhead
whales (Balaena mysticetus) via aspartic acid racemization.
Can. J. Zool. 77: 571–580.
Goto, M. and Inoue, S. 2018. Results of feasibility studies onnovel non-lethal techniques to address the main objectivesof NEWREP-A. Technical Reports of the Institute of Cetacean

Research (TEREP-ICR) No. 2: 56–63.
Helfman, P.M. and Bada, J.L. 1975. Aspartic acid racemization in
tooth enamel from living humans. Proc. Nat. Acad. Sci. USA
72 (8): 2891–2894.
Lockyer, C. 1984. Review of baleen whale (Mysticeti) reproduction and implications for management. Rep. int. Whal.
Commn 6: 27–50.
Maeda, H., Kawamoto, T. and Kato, H. 2013. A study on the improvement of age estimation in common minke whales using
the method of gelatinized extraction of earplug. NAMMCO
Sci. Publ. 10: 17 pp.
Masters, P.M., Bada, J.L. and Zingler Jr., J.S. 1977. Aspartic acidracemisation in the human lens during ageing and in cataract
formation. Nature 268: 71–73.
Nishiwaki, M. 1951. On the periodic mark on the baleen plates
as the sign of annual growth. Sci. Rep. Whales Res. Inst. 6:
133–152.
Olsen, M.T., Bérubé, M., Robbins, J. and Palsboll, P.J. 2012.
Empirical evaluation of humpback whale telomere length
estimates; quality control and factors causing variability inthe singleplex and multiplex qPCR methods. BMC Genetics
13: 77.
Polanowski, A.M., Robbins, J., Chandler, D. and Jarman, S.N.
2014. Epigenetic estimation of age in humpback whales. Mol.
Ecol. Resour. 14 (5): 976–87.
Rosa, C. 2006. Health assessment in the bowhead whale. PhD
thesis, University of Alaska Fairbanks, 213 pp.
Severin, F.F., Feniouk, B.A. and Skulachev, V.P. 2013. Advanced
Glycation of Cellular Proteins as a Possible Component of
the “Master Biological Clock”. Biochemistry (Moscow) 78 (9):1043–1047.
Yasunaga, G., Pastene, L.A., Bando, T., Hakamada, T. andFujise, Y. 2017. Age estimation of Antarctic minke whales
Balaenoptera bonaerensis based on aspartic acid racemization technique. Fish Sci 83 (6): 947–954.
Zenitani, R. and Kato, H. 2010. The growth of baleen plates in
Antarctic minke whales, with special reference to the V-shapenotch appearing at the outer edge of the plates. Nippon
Suisan Gakkaishi 76: 870–876 (in Japanese with English abstract).

13

Technical Reports of the Institute of Cetacean Research (2019)

pp. 14–20

Technical Report (not peer reviewed)

A note on g(0) estimates derived from vessel-based sighting surveys
Megumi Takahashi*
Institute of Cetacean Research, 4–5 Toyomi-cho, Chuo-ku, Tokyo 104–0055, Japan*Contact e-mail: takahashi@cetacean.jp

ABSTRACTThis article introduces the concept of g(0), the probability of detection of animals at zero distance from thetrackline, in the development of abundance estimates of large whales. In the conventional line transect
method, it is assumed that g(0)=1, meaning that all animals on the trackline are detected. However, this assumption is sometimes violated, which causes underestimation of the abundance. Also this article provides
overviews of the methods used to estimate g(0) for large baleen whales, and of the current work of the Institute of Cetacean Research to estimate g(0) based on dedicated sighting surveys in the Antarctic.

INTRODUCTION
Abundance estimates of animals can be based on total
counts (census), sample counts, index counts, among
others. The method producing the most accurate estimate is probably the total census of animals in a given
area. This is possible when the area is small, the visibility
is good, the target species is easily detectable, and when
there is no emigration and immigration. However, these
conditions are diﬃcult to meet for most of the large
whale species. In such cases, the sample counts approach
is more appropriate. Under this approach, the abundance
estimate is extrapolated from data obtained from a partof the total research area.
Distance Sampling (DS) methods (Buckland et al., 2001)

Figure 1.

14

are widely used for estimating whale abundance in large
areas. The line transect method is one of those methods,
in which detailed surveys are conducted along a tracklinethat covers part of the entire survey area (Figure 1A).
The detection probability of whales is not constant but
decreases with the distance from the trackline (Figure
1B). Hence, in conventional line transect methods it isassumed that the detection probability on the trackline,g(0), is equal to 1. This means that all whales on the trackline are detected (Buckland et al., 2001).
However, whale schools are not always detected even
if they are on the trackline because whales dive and because observers could miss the schools on the trackline.
In such cases a g(0) estimate is required for correction ofabundance estimates.

Diagram showing the zigzag tracklines in part of the total research area under the line transect survey (A);and the pattern of detection probability in relation to perpendicular distances (B).

A note on g(0) estimates derived from vessel-based sighting surveys

The objective of this article is to introduce the conceptof g(0) in the development of abundance estimates oflarge whales. Also this article provides overviews of themethods used to estimate g(0) for large baleen whales,
and of the current work of the Institute of Cetacean Research (ICR) to estimate g(0) based on dedicated sighting
surveys in the Antarctic.

AVAILABILITY AND PERCEPTION BIASES
Under the conventional DS methods (Buckland et al.,
1993; 2001), g(0) is assumed as equal to 1. However,when this assumption is violated, conventional DS estimators result in density and abundance being underestimated. In the case of whales, they are not always detected because they spend time underwater. This is known
as ʻavailability biasʼ (Figure 2). This bias is potentially thelargest problem for long-diving species that spend little
time at the surface when the boat or ship surveys are
conducted. For diving species, it may be necessary tomodel diving behavior to estimate the availability bias
(e.g. Barlow, 1999).
Also, the observers could miss some whales available
at the surface for a variety of reasons including visibility
such as glare and mist, fatigue or moments of inattention. This is known as ʻperception biasʼ (Figure 2). Thisbias is potentially largest for species that occur as single
animals or in small groups and do not show much of theirbody when surfacing, such as Hectorʼs dolphin and minke
whales (Dawson et al., 2004).
Both availability and perception biases may reduce thedetection probability. In many cases, there is a combined
eﬀect of these on estimates of abundance and density
for target species. The term ʻvisibility biasʼ is used generi-

Figure 2.

cally to refer to either or both types of biases (Laake andBorchers, 2004).
If the assumption of g(0)=1 is violated then the abundance estimates of the target species will be underestimated. For example, Marsh and Sinclair (1989) estimatedthat 83.3% of dugons (Dugong dugon) were beneath thewater surface and unavailable for detection, while theobserver team only missed 2–17% of the visible dugongs
within a 200 m strip. Laake and Borchers (2004) notedthat the availability bias should not be ignored if it occurs,
because it can be a substantial source of bias that may bemuch larger than perception bias.
Therefore estimates of g(0) for cases of availability andperception biases are important and data required forsuch estimates should be collected.

DATA REQUIRED FROM THE FIELD TO ESTIMATEg(0) IN CASE OF LARGE WHALESThe ICR conducts sighting surveys based on the distancesampling for estimating abundance of large whales. In
general, the surveys follow the Requirements and Guidelines for Conducting Surveys and Analysing Data within
the Revised Management Scheme of the International
Whaling Commission Scientiﬁc Committee (IWC SC)(IWC, 2012). Details of the procedures are found in Hakamada and Matsuoka (2017).
These surveys have been implemented on predetermined zigzag tracklines. The start point is randomly
selected for each survey. The design takes care not tofollow physical features such as isobaths that may be correlated with whale distribution and their migration. For
each whale school sighted, the species is identiﬁed andother data are recorded such as sighting position, school

Diagram showing the detection probability with assumed g(0)=1 (A); and the case of considering availability
and perception biases when g(0) is diﬀerent from 1 (B) (modiﬁed from https://workshops.distancesampling.
org/stand-intermed-2018/slides/mrds1-g0.pdf).
15

Technical Reports of the Institute of Cetacean Research (2019)

size, weather information, etc.
Sighting data are collected from two platforms available in the same vessel, which allows accounting foranimals missed on the trackline. Sighting surveys are
conducted by using a top barrel platform (TOP) and an independent observer platform (IOP). Sighting surveys are
conducted from two platforms independently, following
established procedure protocols (Butterworth and Borchers, 1988; Palka, 1995; Matsuoka et al., 2003; IWC, 2012).
Under the IO mode, sighting surveys are conductedfrom the TOP and the IOP. Personnel at the upper bridgeof the vessels record the sighting information from thetwo platforms and determine if the same sighting is madefrom the two platforms or if some sightings are missedfrom one of the platforms.
Figure 3 shows the research vessel Kaiyo-Maru No.7
(KY7) equipped with TOP, IOP and upper bridge. The vessel has instruments allowing contact between TOP andupper bridge, and between IOP and upper bridge.
During the survey, one or more observers are always in
the TOP, and one observer is in the IOP. Other observers
are in the upper bridge getting sighting information fromthe two platforms. Observers in the top barrel and IOP report the sightings to the upper bridge observers, but that
information is not interchanged between TOP and IOP.
Figure 4 shows a diagram of double-platform sighting
survey and judgment of duplicate status. Here, a single

whale appears three times, which is detected by platform
A (TOP). On the other hand, platform B (IOP) detects thesame whale only during the last surfacing (A3). Observers in the upper bridge receive sighting information (e.g.
distance, angle, species and school size) from platform A
at the ﬁrst sighting (A1) and track this single whale until
platform B observed it. They make a judgment concerning the duplicate status (same whale sighted by the two
platforms).

ANALYTICAL APPROACHES TO ESTIMATE g(0)MRDS method
The method called ʻMark-Recapture Distance Samplingʼ
(MRDS) is one of the methods employed to estimate g(0),which consists of two models: a multiple covariate MarkRecapture (MR) model (for estimating observer detection
rates) and a multiple covariate Distance Sampling (DS)model (for estimating the variation of detection probabilities with distance from the vessel) (Buckland andTurnock, 1992; Alpizar-jara and Pollock, 1996; Quang andBecker, 1997; Borchers et al., 1998; Innes et al., 2002;
Laake and Borchers, 2004; Borchers et al., 2006, Burtet al., 2014). The MRDS method deals only with perception bias.
The probability that either or both observers detect aschool (or animals) is given by:Pˆ .( y, z ) = Pˆ1 ( y , z ) + Pˆ2 ( y , z ) − Pˆ1 ( y, z ) Pˆ2 ( y, z ) ,where y is the perpendicular distance corrected and z
denotes the covariate. Although observers 1 and 2 areconsidered independent from each other under the IO
mode survey, the detection probability of observers canbe correlated because of factors such as school size. This
heterogeneity is denoted in the probabilities of detection
using a logistic form for the detection function:
Pl |3−l( β z) ,( y, z ) =1+ exp ( β + β y +  β z )exp β0 + β1 y +0Figure 3.

Survey vessel equipped with three platforms for
conducting surveys required for g(0) estimate.

Figure 4.
16

1

K
k=1 k+1 k

K
k=1 k+1 k

where, l can take the values 1 or 2 to represent the observers, β 0, β 1…β K represent the parameters to be esti-

Diagram of the double-platform sighting survey conducted by the ICR.

A note on g(0) estimates derived from vessel-based sighting surveys

mated, and K is the number of covariates. When perpendicular distance diﬀered between duplicates, the average
distance of the duplicate pair are used.
On the other hand, the detection probability awayfrom the trackline is described and estimated by the DSmodel as follows:u (u=A or B) is assumed as:12
  x   y  −,
Qu ( x, y ) = μu exp − σ  σ    u   u  

γ

γ


y2 
Half-normal: f ( y, z ) = exp  −,2 
 2σ ( z ) where 0<μ u ≤1, σ u >0, γ 1, γ 2 >0, μ u is the level parameterof the hazard probability function, σ u is the scale parameter, and γ 1 and γ 2 are the shape parameters (Skaug andSchweder, 1999). The corresponding detection function
from this hazard function is explicitly expressed as: − y  − b 
Hazard-rate: f ( y, z ) = 1 − exp ,σ ( z )   λ ∞
gu ( x) = 1 − exp −   Qu ( x, y ) dy 
v
0
  


where σ and b are the parameters of each functional
form.
Both models can include covariates (e.g. school size,
Beaufort, etc.). In addition, the likelihoods can be treatedas MR model and DS model separately or as combinationof those models. The best model usually is selected using
the Akaike Information Criterion (AIC; Akaike, 1973).
The MRDS method do not consider the availability
bias. Hence, the availability bias should be accounted byanalyses of data from additional experiments (e.g. HeideJørgensen et al., 2010).
Hazard probability model: ʻOKʼ method
This method deals with both availability and perception
biases. The method, called the ʻOKʼ method, was developed by Okamura et al. (2003) by extending the modelof Skaug and Schweder (1999), and by combining themerits of the models of Schweder et al. (1997) and Cooke(2001). Okamura et al. (2003) expanded the concept of
the hazard probability model (Skaug and Schweder, 1999)
to avoid the use of external information for considering
diving behavior (the conventional and simple hazard
probability models require an estimate of the surfacing
rate based on external data).
The hazard probability function Q(x,y) for an observer

Figure 5.

γ1  x  = 1 − exp  − λv −1c2u exp − ,σ u  







where λ is surfacing intensity, ν is constant vessel speed
and c 2u =σ u μ u γ 2−1 Γ(γ 2−1), with Γ being the gamma function.
The ʻOKʼ method is a more general and comprehensive
method that integrates the merits of previous hazard
probability models.

ONGOING STUDIES IN THE ANTARCTICThe ʻOKʼ method explained above (Okamura et al., 2003;
Okamura and Kitakado, 2012) was used previously for
estimating Antarctic minke whale (Balaenoptera bonaerensis) abundance from the IDCR/SOWER data collectedfrom the 1985/86 to the 2003/04 austral summer season.
In that study g(0) was estimated less than 1 for Antarctic
minke whales (0.327 to 0.793). Using this result, theabundance estimates of Antarctic minke whale based on
JARPA data were corrected by application of a regression
model (Hakamada et al., 2013).
Preliminary results of the MRDS method on Antarctic
minke whales
Data were obtained during the surveys conducted from

Research area of the study to estimate g(0) of Antarctic minke whale based on MRDS.
17

Technical Reports of the Institute of Cetacean Research (2019)

December to February from the 2014/15 to the 2017/18
austral summer seasons in Antarctic Area IV, V, and VI(Figure 5). As indicated above, the MRDS method for estimating g(0) requires data collected from IO mode survey.
The data comprised a total of 215 schools, including 63
schools which were observed from TOP and IOP (Figure
6, Table 1). Mean school size was 2.23. Also sightings withperpendicular distance of more than 1.5 n.miles, andthose observed when Beaufort status was higher than six,
were excluded from the dataset.
Table 2 shows the AIC values after ﬁtting explanatory
variables to the DS and MR models. For the DS model,
school size and cue were the most important explanatory
variables. For the MR model, platform and school size
were the most important explanatory variables. For thebest model, detection probability on the trackline was
0.676 (CV=0.092) for the TOP, 0.429 (CV=0.145) for the
IOP, and 0.810 (CV=0.066) for the pooled platforms. The
estimated detection function plots are shown in Figure 7.
The detection probability on the trackline for the Antarctic minke whale was similar to the result from the previous
study based on the ʻOKʼ method and IDCR-SOWER datasets (Okamura and Kitakado, 2012). In addition, this result
was similar to that found for North Paciﬁc common minke
whale. For this species the g(0) for TOP and upper bridge
was estimated at 0.798 by the ʻOKʼ method using the IO
passing mode sighting survey data (Okamura et al., 2010).
Future studies
The estimate of g(0) for Antarctic minke whale based on
the MRDS method was similar to that obtained by the ʻOKʼ
method. The estimate considered covariates that aﬀect thedetection functions. However, the analysis only accounts
for perception bias and did not account for availability bias.
Hence, some additional investigations are needed to esti-

Figure 6.

18mate whale diving pattern as in the case of Heide-Jørgensen
et al. (2010). They considered availability correction factors
using data collected from external experiment survey. Also,model development is needed, for example, correction for
non-uniform density of animals within strata using datacollected from external experiment survey, and the use of
the Bayesian hierarchical approach to incorporate habitat
use into a detection model within a mark-recapture distance sampling framework (Oyster et al., 2018), is required.
These studies are ongoing at the ICR.

ACKNOWLEDGEMENTS
I thank the researchers, captains, oﬃcers and crew
members who have participated in all surveys. This work
would not have been possible without the substantial efforts of all of them.
Table 1
Number of sightings of Antarctic minke whales made by eachplatform in each survey. Note that the number of unique sightings is the number of sightings seen by observer 1 plus thenumber seen by observer 2, minus duplicates.
Number of sightings by observers

NumberSurvery ID Platform A Platform B Detected by of uniquebothsightings
(TOP)
(IOP)
(Duplicate)
YS1_1415
YS2_1415
YS3_1516
KY7_1617
YS3_1617
KY7_1718
YS2_1718
Total

14
6
47
6
14
10
79
176

10
1
22
6
10
11
42
102

6
1
14
3
4
5
30
63

18
6
55
9
20
16
91
215

Tracklines and sighting position of Antarctic minke whale observed by each platform (left: TOP; right: IOP).
Gray lines indicate tracklines.

A note on g(0) estimates derived from vessel-based sighting surveys
Table 2
Akaike Information Criterion (AIC) values after ﬁtting explanatory variables to the Distance Sampling (DS) and Mark-Recapture (MR)models. This table shows a part of all result of model ﬁtted for reference. The ﬁnal models chosen are given in bold.
Model ID
35
37
31
32
33
47
103
131
145
54
61
68
40
159

DS modelKey*

Covariate

hn
hn
hn
hn
hn
hn
hn
hn
hn
hn
hn
hn
hr
hr

beaufortcue
size
size+beaufort
size+cuesize+cuesize+cuesize+cuesize+cuesize+cuesize+cuesize+cuesize+cuesize+cue

MR modelCovariate
distance
distance
distance
distance
distance
distance+platform
distance+size
distance+beaufort
distance+cue
distance+platform+size
distance+platform+beaufort
distance+platform+cue
distance
distance+platform+size

AICDS

AICMR

AIC

ΔAIC

141.03134.88126.90128.65115.75115.57115.57115.57115.57115.57115.57115.57118.10118.10472.79472.79472.79472.79472.79437.56469.05473.72474.53434.11438.48439.53472.79434.11613.82607.67599.69601.44588.54553.13584.63589.30590.11
549.69554.06555.10590.89552.21

64.13
57.98
50.01
51.76
38.85
3.44
34.94
39.61
40.42
0.00
4.37
5.42
41.21
2.53

*: hn denotes a Half-normal function; hr denotes a Hazard-rate function.

Figure 7.

Detection function plots for the TOP (A), IOP (B) and both platforms pooled (C) by the MRDS method.

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Technical Reports of the Institute of Cetacean Research (2019)

pp. 21–31

Technical Report (not peer reviewed)

Dedicated whale sighting vessels as a platform for krill andoceanographic research in the Indo-Paciﬁc region of the Antarctic
Atsushi Wada*
Institute of Cetacean Research, 4–5 Toyomi-cho, Chuo-ku, Tokyo 104–0055, Japan*Contact e-mail: wada@cetacean.jp

ABSTRACTThe Institute of Cetacean Research has conducted research on the ecosystem in the Indo-Paciﬁc sector of the
Antarctic, as part of the JARPA, JARPAII and NEWREP-A whale research programs. As part of the ecosystem
research, oceanographic and krill surveys have been carried out in a systematic manner using dedicated sighting surveys as platform. Krill are key species in the Antarctic ecosystem and changes in its abundance have effects on predators and the whole ecosystem. Changes in the oceanographic conditions will aﬀect distribution
and krill biomass and in turn the abundance and distribution of whales. Changes in oceanographic conditions
might indicate eﬀects of climate changes. This paper describes the technical aspects of the krill and oceanographic surveys conducted by the Institute of Cetacean Research from dedicated sighting vessels.

INTRODUCTION
The Institute of Cetacean Research (ICR) has conducted
research on the ecosystem in the Indo-Paciﬁc sector of
the Antarctic in a systematic manner for a considerable
number of austral summer seasons. The ecosystem research involved oceanographic and krill surveys, whichwere conducted as part of the JARPA (1987/88–2004/05),
JARPAII (2005/06–2013/14) and NEWREP-A (2015/16–
2018/19) whale research programs.
Oceanographic and krill research is important tounderstand changes in the Antarctic ecosystem. Krill
are key species in the Antarctic ecosystem and changes
in their abundance have eﬀects on predators and thewhole ecosystem. Changes in the oceanographic conditions will aﬀect distribution and krill biomass and inturn the abundance and distribution of whales. Changes
in oceanographic conditions might indicate eﬀects ofclimate changes. Fujise and Pastene (2018) presented
scientiﬁc evidence for historical and current changes in
the Antarctic ecosystem. Historical changes were consistent with the ʻkrill surplus hypothesisʼ (Laws, 1977; 1985)
while current changes were interpreted as the reverse ofthis hypothesis.
This paper describes the technical aspects of the krill
and oceanographic surveys conducted by the ICR fromdedicated sighting vessels. Oceanographic and krill survey plans and results have been presented and discussed
at annual meetings of the International Whaling Commis-

sion Scientiﬁc Committee (IWC SC) as well the Convention
for the Conservation of Antarctic Marine Living Resources
Working Group on Ecosystem Monitoring and Management (CCAMLR-EMM). Surveys have been designed andconducted by following technical advice of experts fromthese meetings. Also this paper shows as an example, theresults of the oceanographic and krill surveys conductedby NEWREP-A in the 2018/19 austral summer season.

DEDICATED SIGHTING VESSELS
Oceanographic and krill surveys were conducted fromdedicated whale sighting surveys. A total of three research vessels were used during the NEWREP-A, which
covered the IWC management Areas using zigzag
tracklines (Figure 1, Table 1): Yushin-Maru No.2 (YS2;
747GT, Figure 2), Yushin-Maru No.3 (YS3; 742GT, Figure 3)
and Kaiyo-Maru No.7 (KY7; 649GT, Figure 4). The transducers of Quantitative Echosounder (EK80; Simrad, Norway) were hull-mounted at a depth of 4.3 m below thesea surface in the case of YS2 and YS3. The transducers of
Quantitative Echosounder (EK60; Simrad, Norway) were
hull-mounted at a depth of 4.7 m below the sea surface inthe case of KY7. The electrical winch (TS-F2, Tsurumi-Seiki
Co., Ltd., Japan, Figure 5) was set at the right side deck inthe case of YS2 and YS3.

INSTRUMENTS USED FOR KRILL SURVEY
All three survey vessels were mounted with Quantitative
Echosounders for acoustic data recording. These data are21

Technical Reports of the Institute of Cetacean Research (2019)

Figure 1.

Research area and tracklines. Blue line: surveyed trackline of Yushin-Maru No. 2, Green line: surveyed
trackline of Yushin-Maru No.3, Red line: surveyed trackline of Kaiyo-Maru No.7, Gray line: boundary between northern and southern research area, Turquoise line: ice edge, Brown: Antarctic continent.

Table 1
Research area and vessels covered by NEWREP-A. YS2: Yushin-Maru
No. 2, YS3: Yushin-Maru No. 3, KY7: Kaiyo-Maru No. 7.
Area

Season2015/162016/172017/18

2018/19

III-NE
III-SE

YS2
YS2

IV-NW
IV-SW
Prydz Bay
IV-NE
IV-SE

KY7
KY7
KY7
KY7
KY7

YS3
YS3

V-NW
V-SW
V-NE
V-SE
VI-NW
VI-SW
VI-SW*

Figure 2.

Yushin-Maru No.2 (YS2).

Figure 3.

Yushin-Maru No.3 (YS3).

YS3, KY7
YS3, KY7
YS2, KY7
YS2
YS2, KY7
YS2, KY7YS2*Southern of 69°S

used to estimate distribution and biomass of krill in the
research area. Such estimate requires information on krill
species and krill body length, which is obtained from net
sampling. Two types of net sampling were used, IsaacsKidd Midwater Trawl (IKMT) and small ring net sampling.
The IKMT sampling was carried out by KY7 while thesmall ring net was used by YS2 and YS3. Due to its small
size, the small ring net cannot be used for obtaining representative information of some quantitative traits (e.g.
number of individuals and length frequency distribution
22of krill in the area) but the qualitative information (e.g.
the species occurring in the echo-signs) can be obtained.
Quantitative Echosounder
All three vessels steamed on the predeterminedtracklines and acoustic data were recorded continuously.
The usual navigation speed of YS2 and YS3 was approxi-

Dedicated whale sighting vessels as a platform for krill and oceanographic research in the Indo-Pacific region of the Antarctic

Figure 6.

Figure 4.

Procedure for the calibration of EK80 and EK60
Quantitative Echosounders (Based on Simmonds
and MacLennan, 2005).

Kaiyo-Maru No.7 (KY7).

Figure 7.

Figure 5.

The electrical winch at Yushin-Maru No. 3.

mately 11.5 knots. The speed of KY7 was 11.0 knots. All
Quantitative Echosounders operated with frequencies at
38 kHz, 120 kHz and 200 kHz. Maximum data recording
depth was set at 500 m.
Standard calibration of Quantitative Echosounders wasmade using a standard method (Demer et al., 2015) inthe vicinity of Japan and also at the research area before
starting the research. This was done for every survey todetermine the likely eﬀective acoustic sampling range
and the potential for detecting krill for multiple frequencies over the required survey depth.
Also calibration between EK80 (YS2, YS3) and EK60
(KY7) Quantitative Echosounders was conducted when
YS3, YS2 and KY7 passed nearby following the procedureof Simmonds and MacLennan (2005) (Figure 6).

IKMT sampling net at the Kaiyo-Maru No. 7.

IKMT sampling
As noted above, the KY7 was equipped with an IKMT
designed by Nippon-Kaiyo Co., Ltd. Japan (Figure 7). The
purpose of IKMT sampling was the collection of qualitative and quantitative information for krill (e.g. determination of the species occurring in echo signs andrepresentative numbers and krill length frequencies). The
sampling was conducted during day time. The IKMT was
3.66 m in mouth diameter and 18.43 m length. For comparative purposes with the small ring net, 0.5 mm meshsize was used for IKMT.
Data Storage Tag (DST) was installed at the mouth of
the IKMT to record actual depth of the net. On average,
it took approximately 11 minutes per haul excludingtime for setting. The target depth of net sampling was
set based on depth of echo sign but the maximum depth
was 200 m. The depth of the mouth was monitored at thebridge by PI sensor (PI32; Simrad, Norway). Towing speedof IKMT was 1.0 m/s.
Small ring net sampling
All three vessels were equipped with a small ring net that
had a mouth opening of 1.0 m across, and 2.4 m or 3.0 m
length. Mesh size was 0.5, 1.5 or 4.5 mm (Nippon-Kaiyo
Co., Ltd. Japan, Rigosha & Co., Ltd. Japan, Figure 8) (Tra23

Technical Reports of the Institute of Cetacean Research (2019)

than et al., 2001). At the time of the sampling the vessels
stopped their engines.
The target depth of net sampling followed echo backscattering to a maximum of 200 m. If a Light Emitting
Diode (LED) and digital compact camera were attachedto the net, the maximum depth was switched to 100 m
because of their pressure capacity. The depth of themouth was estimated visually from the angel of the wirewith a protractor. The accurate depth of the mouth was
conﬁrmed by DST record in the laboratory. If DST were
not used, the accurate depth of the mouth was checkedby PI sensor at the ﬁeld. Hauling speed of the net was approximately 1.0 m/s depending on sea state.
The small ring net sampling was conducted to identify
the species targeted by echo signs. Notably, the purposeof using this net in KY7, was to check eﬃciency of thesmall ring net by comparing the samples with those obtained by IKMT. If the small ring net samples collected sufﬁcient amount of samples to examine length frequency ofkrill and the composition of plankton samples was similar
to those collected by IKMT, the result of the small ring
net are useful. The small ring net hauls were carried out
as in YS2 and YS3, but were only conducted where IKMT
collected swarms of krill.
Sample treatment
All plankton samples were kept in bottles with 10% formalin and/or frozen at −20°C for further analysis in thelaboratory. Preliminary standard measurements (AT) of
krill sampled, were carried out onboard the vessels. The
AT is measured from the front of the eye to the tip of thetelson, the thin, tapered triangular plate at the end of theabdomen (CCAMLR, 2011, Figure 9).
Recording depth of net
A Data Storage Tag (DST Centi-ex, Star Oddi Co., Ltd.,
Iceland, Figure 10) was put at the mouth of the small
ring nets and IKMT for recording temperature and depth
at one second intervals. Temperature Depth Recorders(TDR, AL1, Ishida Engineering, Japan, Figure 11) and PI
sensors were used as an alternative to DST in 2015/16
and 2017/18 NEWREP-A, respectively. The TDR was put inmouth of the net for recording temperature and hydraulic pressure. The PI sensor was put on the small ring net

Figure 9.

Measurement of total body length (AT) of krill(CCAMLR, 2011).

Figure 10.

Figure 8.
24

Small ring net at the Yushin-Maru No. 2.

Figure 11.

The Data Storage Tag (DST).

The Temperature Depth Recorder (TDR).

Dedicated whale sighting vessels as a platform for krill and oceanographic research in the Indo-Pacific region of the Antarctic

Figure 12.

LED with camera used for attracting krill in thesmall sampling net.

and depth read from the display directly at one minuteintervals.
Attracting krill
In some surveys small net sampling was conducted with
LED and a movie recorded the appearance of the mouth.
Almost in all net sampling, a maximum 3,000 lumen LED(FIX NEO 3000 DX, Fisheye Co., Ltd., Japan), digital compact camera (TG-4 Tough, Olympus Co., Ltd., Japan) andhousing system (Nauticam TG3, Fisheye Co., Ltd., Japan)(Figure 12) was put in mouth of net (Wiebe et al., 2004).
The lighting system was not used after the 2015/16
NEWREP-A following recommendations by CCAMLR specialists (CCAMLR, 2016).

INSTRUMENTS USED FOR OCEANOGRAPHICSURVEYS
Oceanographic observations were based on Japan Meteorological Agency (1999) standards and conducted inparallel with krill surveys.
CTD casting
Hydraulic pressure, temperature, salinity, chlorophyll-aand dissolved oxygen were recorded from sea surface
to 500 m depth using Conductivity-Temperature-Depth
proﬁler (CTD). The CTD SBE 19 plus V2 SeaCAT (Sea-Bird
Scientiﬁc Inc., USA, Figure 13) was used by the YS2 andYS3, and the SBE 19 plus SeaCAT (Sea-Bird Scientiﬁc Inc.,
USA) was used by the KY7. The instruments were descended using an electrical winch with diameter of 3 mm
and an overall length of 1,000 m wire. Normally CTD wasdescended to 500 m. The data from the CTD was uploaded for conversion by following the manual. All CTD were
calibrated before every cruise by Sea-Bird Scientiﬁc Inc.

Figure 13.

CTD at Yushin-Maru No. 2.

Seawater sampling
The seawater sampling was carried out for calibrating the
CTD sensors. Niskin water sampling bottles Model-1010
1.2L (General Oceanics, Inc., USA, Figure 14) were used
by YS2 and YS3 and Model-1010 1.7L (General Oceanics,
Inc., USA, Figure 15) was used by KY7. The bottles were
dropped to depths from 0 to 200 m and sampling was
conducted every 20 m. Depth information of samplingbottles was based on the angle of the wire while operating. Accurate depths of sampling bottle were recorded at
the laboratory from the DST or PI sensor.
The seawater was kept in freezers for subsequent
analysis in the laboratory. The sea water was kept in twobottles. One was a 250 mL clarity seawater bottle (WOCE
type 5419-C, Rigosha & Co. Ltd., Japan) for salinity calibration, which was stored at 4°C. The other bottle was forchlorophyll-a calibration. 118 mL of seawater from thebottles was ﬁltrated (Whatman 233303 GF/F 25 mm, GE
Healthcare, USA) (Figure 16). The ﬁlter paper was kept in
8 mL centrifugal tubes (60.452, Sarstedt AG & Co., Germany) ﬁlled with dimethylformamide. The tubes were
stocked in freezer about −20°C (Saito, 2007). After thecruises, salinity was measured by Autosal Salinometer
OSIL 8400B (Ocean Scientiﬁc International Ltd, UK) and
chlorophyll-a was measured by TURNER 10AU Field andLaboratory Fluorometer (Turner Designs, Inc., USA).

25

Technical Reports of the Institute of Cetacean Research (2019)

HOW THE KRILL AND OCEANOGRAPHIC SURVEYS
ARE CONDUCTED FROM A WHALE SIGHTINGVESSEL?

Figure 14.

Niskin water sampling bottle at Yushin-Maru No. 2.

Figure 15.

Niskin water sampling bottle at Kaiyo-Maru No. 7.

Figure 16.

26

Filtrating seawater with ﬁlter paper.

The trackline was designed for the main purpose of abundance estimates of large whales based on the DISTANCE
sampling (Buckland et al., 2015). It followed the accepted
guidelines by the IWC SC for the International Decadefor Cetacean Research/Southern Ocean Whale andEcosystem Research (IDCR/SOWER) cruises (Matsuoka
et al., 2003). The trackline consisted of a zigzag coursechanging direction at each 5°00ʼ longitudinal degree intervals in the northern stratum and at 2°30ʼ longitudinal
degree intervals in the southern stratum. The trackline in
the Ross Sea was set zigzag in north and south to westward or eastward. The zigzag course changed direction at
1°30ʼ latitudinal degree intervals. Also the trackline in the
Prydz Bay changed direction in northward or southward
at 2°30ʼ longitudinal degree intervals. A randomized startpoint was determined based on the IWC SC guidelines(IWC, 2012).
The sighting surveys were conducted during the daytime from an hour after sunrise to an hour before sunset.
The vessel would move through the tracklines at a speedof 11.0–11.5 knots. The survey stopped when the sea
conditions and weather were not appropriate for sighting activities. When the conditions improved, the vessel restarted the survey from the same position on the
trackline. Three researchers participated onboard thevessels, two in charge of the sighting survey and one incharge of the krill and oceanographic surveys.
Details of the sighting survey procedures used by the
ICR can be found in Hakamada and Matsuoka (2017).
Krill survey
The Quantitative Echosounder data were recorded continuously while vessels steamed on the predeterminedtracklines, day and night. Only the acoustic data obtained
when the vessels were on the trackline are used for krill
abundance estimates.
All net sampling was conducted following the echo
sign by the Quantitative Echosounder (Figure 17). Whenthe researcher conﬁrmed a swarm of krill and decided to
tow the net, the sighting survey was stopped and preparation for net sampling was made as soon as possible. In
principle, net sampling was conducted once a day in the2015/16 and 2016/17 NEWREP-A. In order to increase
the number of samples, net sampling was conducted
after each conﬁrmation of echo signs in the 2017/18 and2018/19 NEWREP-A.

Dedicated whale sighting vessels as a platform for krill and oceanographic research in the Indo-Pacific region of the Antarctic

2018/19 NEWREP-A in management Areas III-E and IV.
The surveys were conducted by the research vessels YS2and KY7.

Figure 17.

Echo sign of Antarctic krill by the EK80 of
Yushin-Maru No. 3.

During the IKMT sampling, the vessel steamed approximately at 2.0 knots. In the case of small ring net sampling,
the vessels stopped their engines when reconﬁrming
echo sign. Both sampling was conducted with careful
conﬁrmation of krill swarm location by monitoring of the
Quantitative Echosounder. When the net sampling wascompleted, the vessel re-started sighting surveys fromthe same position on the trackline that had stopped forthe sampling. Preliminary analyses of the sample werecarried out immediately after sampling.
Oceanographic survey
It was planned that oceanographic observations using
CTD casting would cover the whole area, and for this reason the geographical position of the CTD casting stations
would not necessarily coincide with the position of the
net sampling. The CTD casting stations were positioned
at approximately 60 n.miles on the trackline. The vessels stopped their engines when they arrived at the CTD
casting station. Once observations were completed, they
re-started the sighting surveys from the same positionon the tracklines where the vessels had stopped theirengines.
To calibrate the CTD sensors, the stations for seawater
sampling were the same as some CTD casting station.
Each station was positioned approximately within a radius of 120 n.miles in entire research area for covering
the entire area.
Net sampling, CTD casting and seawater sampling wereconducted during day time and smooth sea states.

RESULTS OF THE 2018/19 KRILL AND OCEANOGRAPHIC SURVEY
As an example, this section shows the results of the

Quantitative Echosounder
Calibrations of Quantitative Echosounders were madeon 30 October 2018 by YS2 and on 7 November 2018 by
KY7 in the vicinity of Japan before departure for the Antarctic. During the calibrations, the vesselʼs engines were
stopped for anchoring at sea bottom 37 m for YS2 and48 m for KY7. Calibrations in the survey area were madeon 13 December 2018 by YS2 and on 6 December 2018 by
KY7 before starting the survey on the tracklines. During
the calibrations, the vesselʼs engines were stopped andthe drifting speed was approximate 0.7 knots because
anchoring at that depth could not be achieved in the Antarctic. The data from the Quantitative Echosounders wasrecorded according to setting of calibration in Antarctic.
The Quantitative Echosounders calibration (EK80 in
YS2 and EK60 in KY7) was conducted on 12 November
2018 in Japanese coastal areas. The methodology of
Simmonds and MacLennan (2005) was followed. The
Quantitative Echosounder data were recorded by YS2
and KY7 moving in formation with one in the lead and theanother about 400 m astern, far enough to the side to beclear of the leader vessel's wake. The two vessels took thelead in turns and exchanged positions at the end of eachtransect. Both research vessels recorded Quantitative
Echosounders data while shifting the leaders every 30
minutes four times for two hours. As a result, calibrations
between EK80 and EK60 were recorded shallow over
200 m sea bottom backscattering constantly by all threefrequencies, 38 kHz, 120 kHz and 200 kHz.
Table 2 shows a summary of the total eﬀort spent on
the Quantitative Echosounder survey. This survey was
conducted for a total of 7,195 n.miles along the tracklines(3,365 n.miles in Area III-E, 2,267 n.miles in Area IV-W,
509 n.miles in Prydz Bay and 1,055 n.miles in Area IV-E).
IKMT sampling
IKMT sampling was conducted at a total of 22 stations
by KY7 (10 stations in Area IV-W, seven stations in the
Prydz Bay and ﬁve stations in Area IV-E, Tables 2, 3 andFigure 18). Logistical considerations were also taken into
account to decide whether to proceed with net samplingsuch as the sea state, sea ice as well as other survey priorities.
Small ring net sampling
The small ring net sampling was conducted at a total of 54
27

Technical Reports of the Institute of Cetacean Research (2019)
Table 2
Research item and summary in the 2018/19 NEWREP-A.
Quantitative
Echosounder

Area

IKMT
stations

Small ring net
stations

CTD castingstations

Seawatersampling
stations

DST
stations

Days

n.miles

III-NE
III-SE

39
32

2,175
1,191

—
—

17
28

42
27

5
2

17
28

IV-NW
IV-SW
Prydz Bay
IV-NE
IV-SE

15
17
6
8
9

1,254
1,013
509
587
468

3
7
7
1
4

0
6
1
2
0

19
23
11
8
14

3
2
2
1
1

3
14
7
3
4

Total

72*

7,195

22

54

144

16

76

*The survey was conducted some areas at same day
Table 3
Summary of IKMT sampling in 2018/19NEWREP-A.
Antarctic krill

Area

Ice krill

Bigeye krill

Euphausiids

Copepoda

Other
Zooplankton

FishStations%

Stations%

Stations%

Stations%

Stations%

Stations%

Stations

%

IV-NW
IV-SW
Prydz Bay
IV-NE
IV-SE

2
6
6
0
2

67
86
86
0
50

0
0
1
0
0

0
0
14
0
0

1
0
0
0
0

33
0
0
0
0

0
1
0
0
3

0
14
0
0
75

0
0
1
1
1

0
0
14
100
25

0
2
1
1
2

0
29
14
100
50

1
0
1
0
0

33
0
14
0
0

Total

16

73

1

5

1

5

4

18

3

14

6

27

2

9

YS2 and on 6 December 2018 and 30 January 2019 by KY7
respectively.
Sample contents of the net
A total of 11 species, including three euphausiid species:
Antarctic krill (Figure 20), ice krill E. crystallorophias (Figure 21) and bigeye krill Thysanoessa macrura (Figure 22)
and ﬁsh (Figure 23 and 24), were identiﬁed in the 73 net
sampling contents. Several other species, Hydromedusae,
Siphonophorae, Polychaeta, Pteropoda, Copepoda (Figure 25), Amphipoda and Chaetognatha were conﬁrmed
by small ring net sampling and IKMT sampling. There
were no contents at three net sampling stations.
Figure 18.

Antarctic krill sample of IKMT.

stations by YS2 and KY7 (45 stations in Area III-E, six stations in Area IV-W, one station in the Prydz Bay and two
stations in Area IV-E, Tables 2, 4 and Figure 19). Becauseof weather, sea ice conditions or survey priority reasons,some net sampling stations were skipped. Calibration of
the ﬂow meters was conducted on 10 December 2018 by
28

Distribution of krill
Tables 3 and 4 show the summary of frequencies of occurrence of krill species and Copepoda sampled by the
IKMT and small ring nets, respectively. Antarctic krill was
sampled at 48 stations in entire of survey area. Distribution of surface water temperature was in the range of−1.7°C to 1.9°C. The Antarctic krill were sampled at depths

Dedicated whale sighting vessels as a platform for krill and oceanographic research in the Indo-Pacific region of the Antarctic
Table 4
Summary of small ring net sampling in 2018/19NEWREP-A.
Area

Antarctic krill

Ice krill

Euphausiids

Bigeye krill

Other
Zooplankton

Copepoda

Stations%

Stations%

Stations%

Stations%

Stations%

Stations%

III-NE
III-SE

7
21

41
75

0
0

0
0

6
3

35
11

0
0

0
0

12
18

71
64

16
20

94
71

IV-NW
IV-SW
Prydz Bay
IV-NE
IV-SE

—
4
0
0
—

—
67
0
0
—

—
0
0
0
—

—
0
0
0
—

—
0
0
0
—

—
0
0
0
—

—
0
0
0
—

—
0
0
0
—

—
0
0
1
—

—
0
0
50
—

—
1
1
1
—

—
17
100
50
—

Total

32

59

0

0

9

17

0

0

31

57

39

72

Figure 19.

Antarctic krill sample of small ring net.
Figure 21.

Ice krill.

Figure 20.

Antarctic krill.
Figure 22.

of 19 m to 146 m, depth of sea bottom range was 178 m
to 5,240 m. The range of body length was from 12 mm to59 mm. The incubating Antarctic krill was sampled at two
stations in Area III-SE. Ice krill was sampled at a station in

Bigeye krill.

the Prydz Bay, distribution of surface water temperature
was 1.6°C. They were sampled at depths of 130 m, depthof sea bottom was 670 m. Bigeye krill were sampled atten stations, distribution of surface water temperature
29

Technical Reports of the Institute of Cetacean Research (2019)

Figure 23.

Antarctic silverﬁsh (Pleuragramma antarcticum).

Figure 24.

Myctophidae.

Comparison of IKMT and small ring net
Simultaneous samplings with the small ring net and
IKMT were conducted at seven stations by KY7. In threecases, Antarctic krill was sampled by both IKMT and small
ring net. However, for the other four cases, the resultsfrom both nets were not consistent. In the 2016/17 and2017/18 NEWREP-A, a total of seven cases of simultaneous sampling occurred, two cases were consistent for
both nets (Wada et al. 2017; 2018). These results indicatethat it is diﬃcult to collect representative krill samples
by the small ring net. However, the small ring net cancontribute to obtaining qualitative information on the
distribution of krill species and it requires less time incomparison to IKMT sampling.
Oceanographic observation
The oceanographic observation by CTD casting was
conducted at 144 stations by YS2 and KY7 (69 stations
in Area III-E, 42 stations in Area IV-W, 11 stations in the
Prydz Bay and 22 stations in Area IV-E, Table 2). The
seawater sampling was conducted at 16 stations at thesame locality where CTD castings were taken. Seven stations in Area III-E and ﬁve stations in Area IV-W, two stations in the Prydz Bay and two stations in Area IV-E were
sampled (Table 2). A total of 176 seawater samples weretaken then kept in clear bottles for salinity calibration.
For chlorophyll-a calibration samples were ﬁltered andstored with dimethylformamide.

ANALYSES OF DATA

Figure 25.

Copepoda.

was in the range of −1.4°C to 1.0°C. They were sampled at
depths of 35 m to 146 m, depth of sea bottom range was
2,100 m to 5,240 m. The range of body length was from
10 mm to 25 mm.

30

The main objective of krill and oceanographic surveys
was to estimate the abundance of Antarctic krill acoustically, and to obtain the length frequency distribution andmaturity stage of Antarctic krill in the survey area.
Quantitative Echosounder data is used for estimating
krill abundance. The software Echoview 9 (Echoview Software Pty. Ltd., Australia) is used for calculating backscattering of krill after noise removal. Estimate value of krill
abundance is obtained from this backscattering in eachresearch area. This estimate requires identiﬁcation of krill
species and body length obtained by the IKMT samplingand small net sampling.
The oceanographic data is used for identifying structure of ocean currents likely Upper Circumpolar Deep
Water, Lower Circumpolar Deep Water and Shelf Water
based on CTD data. These currents are assumed in relation to the distribution of krill and predators.
The analyses are being conducted by the ICR and several external research organizations.

Dedicated whale sighting vessels as a platform for krill and oceanographic research in the Indo-Pacific region of the Antarctic

ACKNOWLEDGEMENTS
I would like to thank the Government of Japan for providing support for this survey, and the captains and crew
members of YS2, YS3 and KY7 for their eﬀort at the ﬁeld.
I also thank several scientists that supported the designand development of the krill and oceanographic surveys.

REFERENCES
Buckland, S.T., Rexstad, E.A., Marques, T.A. and Oedekoven, C.S.
2015. Distance sampling: Methods and applications. Springer
International, Switzerland. 277 pp.
Commission for the Conservation of Antarctic Marine Living
Resources. 2011. The CCAMLR—Scientiﬁc observers manual(Observation guidelines and reference materials): 16.
Commission for the Conservation of Antarctic Marine Living
Resources. 2016. Report of the working group on Statistics,
Assessments and Modelling, June 2016: 3–4.
Demer, D.A., Berger, L., Bernasconi, M., Bethke, E., Bowswell,K., Chu, D., Domokos, R., Dunford, A., Fässler, S., Gauthier, S.,
Hufnagle, L.T., Jech, J.M., Bouﬀant, N., Dhaussy, A.L., Lurton,
X., Macaulay, G.J., Perrot, Y., Ryan, T., Stetter, S.P., Stienessen,S., Weber, T. and Williamson, N. 2015. Calibration of acoustic
instruments. ICES Cooperative Res. Rep. No. 326: 1–87.
Fujise, Y. and Pastene, L.A. 2018. Cetaceans as indicators ofhistorical and current changes in the Antarctic ecosystem.
Technical Reports of the Institute of Cetacean Research(TEREP-ICR) No.2: 1–13.
Hakamada, T. and Matsuoka, K. 2017. Sighting survey procedures for abundance estimates of large whales in JARPA and
JARPAII, and results for Antarctic minke whales. Technical
Reports of the Institute of Cetacean Research (TEREP-ICR)
No.1: 28–36.
International Whaling Commission. 2012. Requirements andguidelines for conducting surveys and analysing data within
the Revised Management Scheme. J. Cetacean Res. Manage.
(Suppl.) 13: 509–517.

Japan Meteorological Agency. 1999. Manual on oceanographic
observation part 1. Japan Meteorological Business Support
Center, Tokyo. 200 pp (in Japanese).
Laws, R.M. 1977. Seals and whales of the Southern Ocean.
Philos. Trans. R. Soc. Lond. B 279: 81–96.
Laws, R.M. 1985. The Ecology of the Southern Ocean. Am. Sci.
73: 26–40.
Matsuoka, K., Ensor, P., Hakamada, T., Shimada, H., Nishiwaki,S., Kasamatsu, F. and Kato, H. 2003. Overview of minke
whale sighting surveys conducted on IWC/IDCR and SOWER
Antarctic cruises from 1978/79 to 2000/01. J. Cetacean Res.
Manage. 5: 173–201.
Saito, H. 2007. Nihonkai Shuhen Kaiiki Ni Okeru Teiji Seitaikei
Monitoring Ni Okeru Keikoho Ni Yoru Chlorophyll-a Bunseki
Manual version 1d. Tohoku National Fisheries Res. Inst. (unpublished). 12 pp (in Japanese).
Simmonds, J. and MacLennan, D. 2005. Fisheries acoustics
theory and practice second edition. Blackwell Sci.: 326–328.
Trathan, P.N., Watkins, J.L., Murray, A.W.A., Brierley, A.S.,
Everson, I., Goss, C., Priddle, J., Reid, K., Ward, P., Hewitt,
R., Demer, D., Naganobu, M., Kawaguchi, S., Sushin, V.,
Kasatkina, S.M., Headley, S., Kim, S. and Pauly, T. 2001. The
CCAMLR-2000 krill synoptic survey: a description of the rationale and design. CCAMLR Sci. Vol. 8: 23 pp.
Wada, A., Konishi, K., Bansho, S., Kasai, H., Igarashi, Y. andTamura, T. 2017. Result of the krill and oceanographic survey under the NEWREP-A in the Antarctic in 2016/17. Paper
SC/67a/EM9 presented to the IWC Scientiﬁc Committee, May
2017 (unpublished). 9 pp. [Available from the IWC Secretariat].
Wada, A., Mogoe, T., Bansho, S., Kasai, H., Sasaki, Y. and Tamura,T. 2018. Result of the krill and oceanographic survey under the
NEWREP-A in the Antarctic in 2017/18. Paper SC/67b/EM5
presented to the IWC Scientiﬁc Committee, April 2018 (unpublished). 12 pp. [Available from the IWC Secretariat].
Wiebe, P.H., Ashjian, C.J., Gallager, S.M., Davis, C.S., Lawson,
G.L. and Copley, N.J. 2004. Using a high-powered strobe
light to increase the catch of Antarctic Krill. Mar. Biol. 144:
493–502.

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Technical Reports of the Institute of Cetacean Research (2019)

pp. 32–40

Technical Report (not peer reviewed)

Genetic study of stock structure in North Paciﬁc sei whales
Mioko Taguchi*
Institute of Cetacean Research, 4–5 Toyomi-cho, Chuo-ku, Tokyo 104–0055, Japan*Contact e-mail: taguchi@cetacean.jp

ABSTRACTThe Institute of Cetacean Research has conducted genetic analyses of stock structure in North Paciﬁc sei
whales based on historical genetic samples, and samples collected more recently by the IWC-POWER (biopsy samples) and JARPNII program. Results have contributed to the in-depth assessment of North Paciﬁc sei
whales conducted by the IWC Scientiﬁc Committee. This paper presents details of the research area, samples,
genetic approaches, and main results of the genetic analyses of stock structure of sei whales in the pelagicarea of the North Paciﬁc. Results of the genetic analyses are consistent with the hypothesis of a single stock of
sei whales in the pelagic area of the North Paciﬁc surveyed (140°E–130°W).

INTRODUCTION
Sei whale, Balaenoptera borealis, (Figure 1) is a large
baleen whale species inhabiting all of the major open
oceans (Horwood, 1987; Rice, 1998). Sei whales live up to
60 years of age and their maximum body length is 20 m.
Sei whales migrate from winter breeding grounds in low
latitude to high latitudinal areas in summer, where they
feed on various prey species (e.g. Nemoto, 1959; Nemoto
and Kawamura, 1977).
This species was one of the major targets of commercial whaling worldwide (Horwood, 1987). In the North
Paciﬁc the main period of exploitation was from 1963
to 1973 (Allen, 1980), and they were caught in watersoﬀ California, Canada, Japan, Kamchatka and the Kuril
Islands by pelagic ﬂeets (Horwood, 2018).
Delineation of the stock structure of the species andthe estimation of abundance by stock are key information
required for management and conservation. A pioneering work on stock structure of North Paciﬁc sei whales
was carried out by Wada and Numachi (1991) using
three polymorphic allozyme loci. The study reported no

Figure 1.
32

evidence of temporal and spatial genetic heterogeneity
in samples collected in the area east of 160°E, suggesting
the existence of only a single stock in the area.
The most comprehensive genetic study was performedby Kanda et al. (2009) using 17 microsatellite DNA lociand 487bp of mitochondrial DNA (mtDNA) control region
sequences. The study used a total of 790 specimens collected during the past commercial whaling in 1972–1973
and during the JARPNII surveys in 2002–2007. Results ofthe study showed no evidence of signiﬁcant genetic differences in areas between 140°E and 135°W of the North
Paciﬁc.
Subsequently, Kanda et al. (2013) examined not only
spatial but also temporal genetic diﬀerences of theNorth Paciﬁc sei whales. The study showed no evidenceof temporal (40 years apart between recent and pastsamples) and spatial (the research area divided into western (140°–170°E), central (170°E–150°W) and eastern(150°–130°W) areas) genetic diﬀerences. Results wereconsistent with those found by Kanda et al. (2009). Furthermore, Kanda et al. (2015a) considered that spatial
genetic diﬀerentiation should be tested using samples

North Paciﬁc sei whale (Balaenoptera borealis).

Genetic study of stock structure in North Pacific sei whales

collected in the same year in order to eliminate temporal
negative biases. Consequently, they examined genetic
variations at 16 microsatellite loci using only samples
collected during summer in 2010, 2011 and 2012. Again,
the results of the study failed to ﬁnd evidence of multiple
stocks of sei whales in the North Paciﬁc.
This paper presents details of the research area,samples, genetic approaches, and main results of thegenetic analyses of stock structure of sei whales in the pelagic area of the North Paciﬁc, updated after the work by
Kanda et al. (2015a). This paper also provides information
on some basic concepts of population genetic statistics.

MATERIALS AND METHODS
Research area
The genetic analyses were conducted based on threesampling areas in the pelagic region of the North Paciﬁc:western (140°–150°E), central (150°E–180°) and eastern(180°–130°W) areas (Figure 2). Genetic samples were collected from whales taken during past commercial whaling operations as well during more recent surveys of the
JARPNII research program. Biopsy samples obtained during the IWC-Paciﬁc Ocean Whale and Ecosystem Research(IWC-POWER) were also used (see details below).
Samples and laboratory procedures
Samples and DNA extraction
A total of 1,748 genetic samples of sei whales obtained
during past commercial whaling in 1972–1973 (n=312),
the JARPNII in 2002–2016 (n=1,354) and the IWC-POWER(biopsy samples) in 2010–2013 (n=82) was subjected to
DNA extraction (Table 1).
Total genomic DNA was extracted from 0.05 g of skintissue, preserved in 99% ethanol at room temperatureor stored frozen at −20°C, using the standard phenol-

Figure 2.

chloroform method (Sambrook et al., 1989) or using Gentra Puregene kits (QIAGEN). Extracted DNA was stored in
TE buﬀer (10 mM Tris-HCl, 1 mM EDTA, pH 8.0).
MtDNA sequencing
See an explanation of mtDNA sequencing analyses in Taguchi et al. (2017).
Approximately 500 base pairs of partial control region
were ampliﬁed by the polymerase chain reaction (PCR)
using a set of primers MT4 (Árnason et al., 1993) and Dlp
5R (5ʹ-CCA TCG AGA TGT CTT ATT TAA GGG GAA C-3ʹ).
PCR was performed with an initial denaturation step at
95°C for 5 minutes, followed by 30 cycles of 30 seconds
at 94°C, 30 seconds at 50°C and 30 seconds at 72°C, witha ﬁnal extension step at 72°C for 10 minutes. PCR products were puriﬁed using MicroSpin S-400HR columns(Pharmacia Biotech). Cycle sequencing was performed
using BigDye terminator cycle sequence Kit (Applied Biosystems) and the PCR primers, following the protocols of
the manufacturer. The cycle sequencing products were
puriﬁed using AutoSeq G-50 spin Columns (Pharmacia
Biotech). The labeled sequencing fragments from tissue
samples collected until 2004, during 2005–2010, andTable 1
Number of genetic samples of North Paciﬁc sei whales used inthis study. Sample size for the present data analyses is shown inparenthesis (mtDNA sequences, microsatellite genotypes).
Sample source
Past commercial whaling
JARPNII
IWC-POWER
Total

Sampling area
Western

CentralEastern

181 ( 175, 177) 131 (128, 121)
30 (30, 30) 1324 (1322, 1323)
3(3,3) 79 ( 75, 75)

30 (30, 30) 1508 (1500, 1503) 210 (203, 196)

Sampling position of sei whales used in the genetic analyses. Color indicates sample source: yellow: pastcommercial whaling; red: JARPNII; and blue: IWC-POWER.
33

Technical Reports of the Institute of Cetacean Research (2019)from 2011 were resolved using an ABI PRISM 377, ABI
PRISM 3100 and ABI3500 Genetic Analyzers (Applied Biosystems), respectively.
Microsatellite DNA genotyping
See an explanation of microsatellite DNA analyses in Taguchi et al. (2017).
All individuals sampled in JARPNII and IWC-POWER
surveys were genotyped at 17 nuclear microsatellite loci: EV1, EV14, EV21, EV94, EV104 (Valsecchi
and Amos, 1996), GT011 (Bérubé et al., 1998), GT23,
GT211, GT271, GT310, GT575 (Bérubé et al., 2000),
GATA28, GATA53, GATA98, GATA417, GGAA520 (Palsbøll
et al., 1997), and DlrFCB17 (Buchanan et al., 1996). The
past commercial whaling samples were genotyped at 15
microsatellite loci (EV14 and GATA417 were not used).
Primer sequences and PCR cycling proﬁles generally followed those of the original authors. The multiplex PCR
ampliﬁcations were performed in 15 µl reaction mixturescontaining 10–100 ng of DNA, 5 pmole of each primer,
0.625 units of Ex Taq DNA polymerase (Takara Shuzo),
2mM of each dNTP, and 10x reaction buﬀer containing
20mM MgCl2 (Takara Shuzo), with 94°C for 2 minutes, followed by 30 cycles at 94°C for 20 seconds/54–61°C for 45
seconds/72°C for 1 minute, and a post-cycling extension
at 72°C for 10 minutes.
PCR products from tissue samples collected until 2013
were run on a 6% polyacrylamide denaturating gel (Long
Ranger) with internal size standard (GENESCAN400HD,
Applied Biosystems) using BaseStation100 DNA fragment analyzer (Bio-Rad). Although alleles were visualizedusing Cartographer software speciﬁcally designed for the
BaseStation, allelic sizes were determined manually in relation to the internal size standard and sei whaleʼs DNA of
known size that were rerun on each gel. The PCR productsof samples collected after 2013 were electrophoresed on
an ABI 3500 DNA Analyzer (Applied Biosystems), and allele sizes were determined using a 600 LIZ size standard(Applied Biosystems) and GeneMapper v. 4.0 (Applied
Biosystems). Microsatellite scores from the latter platform were standardized according to those from theformer for each locus.
Data analyses
Three whales re-sampled (two genetic samples obtained
from the same individual whale) were excluded fromthe analysis. Three calves accompanied by their mothers
were also excluded from all subsequent analyses, to ensure an independence of the dataset. In addition to this,nine mtDNA sequences data and thirteen microsatellite
34

genotype data sets were also excluded from the present
data set due to their low data qualities.
FDR correction (Benjamini and Hochberg, 1995) wasused to adjust the signiﬁcance level for all multiple comparisons in this study.
Considering a long time series of sample collection ofover 40 years, annual genetic variations were preliminary
examined in each of the sampling areas, which consistently showed no signiﬁcant genetic diﬀerences. Therefore, the genetic data from several years were combinedin each sampling area in all subsequent analyses. Moredetailed descriptions of the temporal analyses were provided in Appendix 7 in Tamura et al. (2019).
Genetic diversities
For microsatellite DNA, the departure from Hardy–
Weinberg equilibrium (HWE: see Box 1) was tested ineach locus using the R package ʻHWxtestʼ (Engels, 2009).
A global test across loci combining the observed P-values
in each locus by Fisherʼs method was performed using
the R package ʻmetapʼ (Dewey, 2018). The inbreeding coeﬃcient (FIS; Weir and Cockerham, 1984) in eachlocus and across loci was estimated using the R package ʻDemerelateʼ (Kraemer and Gerlach, 2017). The
number of alleles (A) and expected heterozygosity (HE:see Box 2) in each locus and across loci were estimatedusing the program ARLEQUIN v. 3.5.1.2 (Excoﬃer andLischer, 2010).
For mtDNA, haplotype (h) and nucleotide (π) diversities (Nei, 1987) (see Box 2) with sample standard deviations were estimated using the program ARLEQUIN.
Genetic diﬀerentiation and structuring
The FST-like estimates for microsatellites and conventional
pairwise FST for mtDNA (see Box 3) were calculated tomeasure the genetic diﬀerentiation between samplingareas using 10,000 random permutations of the original
dataset in the program ARLEQUIN. A probability test
implemented in the program GENEPOP (Rousset, 2008)
was used to detect the genetic heterogeneity in microsatellite allele frequency among sampling areas. Diﬀerence
in mtDNA haplotype frequency among sampling areas
was also tested using the Monte Carlo simulation-based
chi-square test of independence (Roﬀ and Bentzen, 1989)
in R.
Bayesian clustering analysis was performed using microsatellite data to infer the most likely number of clusters
using STRUCTURE 2.3.4 (Pritchard et al., 2000). The analysis was conducted with ten independent runs for K=2–3.
All runs were performed with 100,000 Markov chain

Genetic study of stock structure in North Pacific sei whales

Box 1. Hardy–Weinberg equilibrium
The genetic composition of a population is usually described in terms of allele frequency, number of alleles and heterozygosity. Allele and genotype frequencies attain an equilibrium, referred to as the Hardy–Weinberg equilibrium (HWE), in the next
generation in inﬁnitely large and random mating populations when there are no mutation, immigration or selection. When anyof the assumptions underlying HWE are violated, then deviations from the equilibrium genotype frequencies will be observed.
Thus, the HWE are widely used to detect if the population has non-random mating, migration or selection.
For a single locus with two alleles, HWE genotype frequencies can be expected according to the relationship:

p 2 + 2pq + q 2 =1
where p and q are the respective allele frequencies; p2 =frequency of one allele homozygotes, q2 =frequency of the other allele
homozygotes, and 2pq=frequency of heterozygotes.
To determine if the observed genotype frequencies deviate from the frequencies expected from the HWE relationship statistically, the diﬀerence in number of genotypes between them is tested using a χ 2 test.
As an example, consider a single microsatellite locus GATA53 with alleles 198 and 202 in ten sei whales (See Table 2.1 inBox 2), hence three genotypes (198/198, 202/198, 202/202) are found. From the observed number of respective genotypes, it
is possible to calculate p and q, and to estimate the HWE genotype frequencies based on the allele frequencies calculated fromthe observed genotype frequencies, as shown in Table 1.1.
Table 1.1
Calculation of allele frequencies based on the observed number of genotypes, and the genotype frequencies expected from the
HWE in a microsatellite locus GATA53 of sei whales.
Observed
Genotypes

Expected

Number ofallelesAllelefrequency

198

198

Number of genotypes (O)Genotype
frequency

198/198

1

1/10
0.1

2×1
2

202/198

4

4/10
0.4

1×4
4

202/202

5

5/10
0.5

Total

10

1.0

202

Number of genotypes (E)p2 =0.3×0.3
0.09

0.09×10
0.9

4/20
0.2

2pq=2×0.3×0.7
0.42

0.42×10
4.2

10/20
0.5

q2 =0.7×0.7
0.49

0.49×10
4.9

q=0.7

1.00

10.0

202

2/20
0.1
1×4
4

4/20
0.2

2×5
10
6

Genotype
frequency

14

Monte Carlo repetitions and 10,000 burn-in length using
the admixture model with correlated allele frequencies.
The web-based program STRUCTURE HARVESTER (Earland vonHoldt, 2012) was used to estimate the mean posterior probability of the data (Also see Goto et al. (2017)
for detailed basic concept of the STRUCTURE analysis).

RESULTS AND DISCUSSION
All 17 microsatellite loci were polymorphic in the entire
dataset of 1,729 sei whales from the North Paciﬁc, whichranged from 22 alleles at EV14 to 3 alleles at GATA53(Table 2). The mtDNA control region sequences of 1,733
sei whales from the North Paciﬁc contained 39 variablenucleotide sites and a single alignment gap deﬁning 84
haplotypes.

p=0.3

Genetic diversities
The HE at each locus and across loci were not largely different among sampling areas (Table 2), and the estimatesacross loci ranged from 0.632 in the western area to0.639 in the eastern area (Table 2). Signiﬁcant deviations
from HWE were not observed at any loci and across loci ineach sampling area after FDR correction (Table 2), whichsuggested that North Paciﬁc sei whales in each of thesampling areas derived from a single breeding population.
Regarding mtDNA, both h and π were similar among
sampling areas, which ranged from 0.908 in the westernarea to 0.927 in the eastern area, and from 0.789% in thewestern area to 0.803% in the central area, respectively(Table 3). These observations were consistent with the35

Technical Reports of the Institute of Cetacean Research (2019)

Box 2. Estimating genetic diversity
Genetic diversity is characterized by allele frequencies at each locus, which can be inﬂuenced by population size, gene ﬂow,
reproductive system, natural selection, genetic mutation or genetic linkage. In natural environment, populations are commonly
fragmented into subpopulations in diﬀerent size partly separated from each other by barriers to migration, and this may change
the genetic diversity among populations.
Observed heterozygosity (HO) is deﬁned as the proportion of individuals heterozygous across a set of loci (hj), or the proportionof loci for which an individual is heterozygous (hi). This estimate can be obtained by direct count of heterozygotes, as shown in
Table 2.1. Overall estimates are averages across the loci used in the study.
Table 2.1
Sub-set of data used in this study involving seventeen microsatellite loci genotyped in each of ten sei whales.
Individual (i)Microsatellite
loci (j)SEI-001

SEI-002

SEI-003

SEI-004

SEI-005

SEI-006

SEI-007

SEI-008

SEI-009

SEI-010EV21
GGAA520GATA98GT211
EV14GATA53
EV1
EV94
GT23
GT575
GATA417GT310
EV104
GATA28
GT271
GT011
DlrFCB17

120124217221102110115115155167202202130146219221116118140146220220108110134140228232096096123127
199203120120221221094098115115159179198198130146217217116126138146224224108108134144228232096096123123203207120120217229098106115117155167
198202144162217219116116146148212240108110134140224232096096123123205221118120225229102102115117157167202202146146213221116116138138216232108108140140216236096096123123
199215120126225229102102115115155167202202148152217225112116138138216224108110140144232232096096123129199207120122217233094102115115161161202202146146217219116116138146212228110110134134212220094096123129199203120120213225098102115115155155198202148158217219116116138148220224108108134142224232094096123123209215120124221229102102115115155159202202148152221223116118146146224224108108140142216232094096123127
183205118122217229094106115119155155198202146148217219116116138148212220108108140144232232096096123123
201203120124221225098102115121155155198202130138217221116120138138216220108114140142212232096096123123203211

0.7
0.9
0.7
0.4
0.6
0.4
0.8
0.9
0.5
0.6
0.7
0.4
0.8
0.8
0.3
0.4
1.0

hi

0.765

0.471

0.765

0.471

0.647

0.588

0.647

0.647

0.647

0.765

0.641

hj

Genotypes are represented by 6-digits codes (each allele is coded by 3-digits), and heterozygotes are indicated with red color.
In this example, 109 of 170 assayed genotypes are heterozygous (overall HO =0.641).
Expected heterozygosity (HE) is deﬁned as the expected proportion of individuals heterozygous from observed allele frequencies, assuming the population is in HWE (see Box 1), as shown in Table 2.2. In the case of two alleles at a locus with their respective frequencies of p and q, the expected heterozygosity HE =2pq. When there are more than two alleles, it is simpler to calculate
HE as follows:

H E =1 −

k

p

2
i

i=1

where pi is the frequency of the i-th allele, and k is the number of alleles. HE is normally used rather than HO since it is less affected by sampling.

comparable genetic diversities among sampling areas
observed in microsatellite DNA.
Genetic diﬀerentiations and structuring
Pairwise FST-like estimates for microsatellites did not
36

show any genetic diﬀerentiations between samplingareas (Table 4), which was consistent with the pairwise
conventional FST estimates for mtDNA (Table 4). Heterogeneity tests also showed no diﬀerences in microsatellite
allele (P=0.679, d.f.=34, χ 2 =29.69) and mtDNA haplotype

Genetic study of stock structure in North Pacific sei whales

Table 2.2
Allele frequencies and three statistics of genetic diversity, i.e. number of alleles (A), observed (HO) and expected (HE)heterozygosity, per microsatellite loci based on the data set in Table 1.1
Alleles (i)MicrosatelliteA
lociallele 1 allele 2 allele 3 allele 4 allele 5 allele 6 allele 7 allele 8 allele 9 allele 10
EV21
GGAA520GATA98GT211
EV14GATA53
EV1
EV94
GT23
GT575
GATA417GT310
EV104
GATA28
GT271
GT011
DlrFCB17

0.10
0.05
0.15
0.80
0.50
0.30
0.15
0.05
0.05
0.50
0.15
0.70
0.30
0.10
0.15
0.80
0.05

0.60
0.20
0.20
0.10
0.05
0.70
0.05
0.40
0.75
0.05
0.15
0.25
0.40
0.10
0.85
0.10
0.20

0.10
0.25
0.50
0.05
0.10

0.15
0.20
0.10
0.05
0.10

0.05
0.25
0.05

0.05

0.20

0.05

0.05
0.25
0.10
0.30
0.25
0.05
0.15
0.05

0.35
0.20
0.05
0.15
0.30

0.20
0.05
0.05

0.10
0.05

0.05

0.05

0.05

0.05

0.15
0.10

0.10

0.50

0.05

0.10
0.05

0.25

0.10

0.10

0.05

0.05

0.05

0.10

0.05

Means

HO

HE

0.7
0.9
0.7
0.4
0.6
0.4
0.8
0.9
0.5
0.6
0.7
0.4
0.8
0.8
0.3
0.4
1.0

0.60
0.79
0.68
0.35
0.69
0.42
0.80
0.73
0.42
0.64
0.80
0.45
0.71
0.71
0.26
0.34
0.86

5.1 0.64

0.60

5
6
5
4
6
2
8
6
5
4
7
3
4
7
2
3
10

The averaged statistics over the seventeen loci were shown at the bottom (overall H E =0.60).
For haplotypic data such as mitochondrial DNA, a simple estimate of diversity, which is equivalent to HE for diploid data,
called as haplotype diversity (H) can be also calculated as H=1−∑ki=1p2i, where k is the number of haplotypes, and pi is the frequency of haplotype i (Nei, 1987). In the case of full sequence comparison, nucleotide diversity (π), which is equivalent to H
at the nucleotide level, is given by π=∑ijxixj π ij, where pij is the proportion of diﬀerent homologous nucleotide sites between
haplotypes i and j, and xi and xj are the frequencies of haplotypes i and j, respectively (Nei, 1987).

Box 3. Measuring genetic diﬀerentiation
F-statistics, which is ﬁrst introduced by Wright (1951), is one of important estimators to describe population genetic structure.
This statistics partitions overall genetic diversities into components within and among populations, and can be calculated using
heterozygosity as the following equations (Nei, 1987):

FIS =(hs − hi ) / hs
FIT = (ht − hi ) / ht
FST = (ht − hs ) / ht
where hi is the HO averaged across all populations, hs is the HE averaged across all populations, and ht is the HE for the total population. Two of which, i.e. FIS and FST, are widely used as estimators to describe genetic structure. The FIS (inbreeding coeﬃcient)can be positive indicating a deﬁciency of heterozygotes when inbreeding or population subdivision occur within populations,while negative values indicating an excess of heterozygotes will be observed when outbreeding occurs within populations. The
FST (ﬁxation index) is a common estimator for genetic diﬀerentiation among populations, and varies from 0 (no diﬀerentiation
between populations) to 1 (ﬁxation of diﬀerent alleles in populations).

37

Technical Reports of the Institute of Cetacean Research (2019)
Table 2
Summary statistics for 17 microsatellite loci in North Paciﬁc sei whale in each sampling area.
Microsatellite
loci
EV21
GGAA520GATA98GT211
EV14GATA53
EV1
EV94
GT23
GT575
GATA417GT310
EV104
GATA28
GT271
GT011
DlrFCB17
OverallWestern
n

A

30 5
30 7
30 5
30 4
30 12
30 3
30 12
30 6
30 6
30 4
30 7
30 3
30 5
30 9
30 3
30 4
30 14
6.41

CentralEastern

HE

HWE

FIS

n

A

HE

HWE

FIS

n

A

HE

HWE

FIS

0.706
0.789
0.686
0.295
0.818
0.413
0.814
0.655
0.554
0.603
0.791
0.513
0.743
0.821
0.242
0.415
0.890
0.632

0.667
0.648
0.441
1.000
0.625
0.291
0.814
0.222
0.335
0.378
0.956
1.000
0.847
0.082
1.000
0.889
0.310
0.939

−0.136−0.014−0.0700.099
0.105−0.0500.017
0.085−0.146−0.108−0.0550.026−0.0780.027−0.105−0.128−0.049−0.034

1501
1499
1485
1503
1326
1500
1502
1502
1503
1503
1326
1502
1500
1503
1503
1503
1502

6
9
7
6
22
3
16
8
14
5
9
5
10
11
4
6
20
9.47

0.644
0.802
0.734
0.308
0.865
0.494
0.836
0.685
0.606
0.593
0.782
0.483
0.726
0.812
0.140
0.449
0.872
0.637

0.867
0.965
0.792
0.019
0.846
0.990
0.583
0.519
0.308
0.657
0.449
0.160
0.878
0.559
0.579
0.899
0.106
0.790

−0.0040.004−0.005
0.016
0.001
0.003
0.010
−0.0230.017
0.024−0.005−0.020
0.003
0.016
0.006
0.006
0.012
0.003

196
193
159
194
74
192
196
196
195
190
75
196
191
196
196
196
188

6
9
6
4
14
3
17
6
11
6
8
4
8
10
3
4
17
8.00

0.651
0.792
0.748
0.316
0.861
0.508
0.835
0.702
0.600
0.577
0.785
0.483
0.703
0.825
0.130
0.458
0.882
0.639

0.295
0.833
0.043
0.124
0.862
0.819
0.407
0.287
0.741
0.816
0.561
0.364
0.678
0.719
1.000
0.751
0.165
0.753

−0.0110.059
0.050−0.078−0.0200.015
0.034−0.032
0.008
0.061
0.049
−0.0770.017−0.015
0.022
0.020
0.023
0.007

Table 3
Summary statistics for mtDNA control region in North Paciﬁc sei whale in each sampling area.
Western
mtDNA

CentralEastern

n

h

S.D.

π (%)

S.D.

n

h

S.D.

π (%)

S.D.

n

h

S.D.

π (%)

S.D.

30

0.908

0.036

0.789

0.454

1500

0.925

0.004

0.803

0.446

203

0.927

0.010

0.797

0.445

Table 4
Pairwise FST between sampling areas. Upper and below diagonals indicate results from microsatellite and mtDNA.
Sampling area

Western

Western
CentralEastern−0.00070.0004

CentralEastern−0.0002−0.0010−0.00140.0002(P=0.699, χ 2 =142.09) frequencies among sampling areas.
The clustering patterns in each K estimated by the
program STRUCTURE also did not infer a distinct genetic
structuring of this species (Figure 3). These results suggested absence of genetic structure among sei whales
distributed in the pelagic area of the North Paciﬁc investigated in this study, which was also supported by thefact that genetic diversities were not diﬀerent among
sampling areas in both markers, and there were no departures from HWE in each of sampling areas.

38

Figure 3.

Bar plot of membership probabilities in STRUCTURE
analyses at K=2–3 for North Paciﬁc sei whales. Eachindividual is characterized by a thin vertical line,
which is divided into K colored segments on the basisof the individualʼs membership fractions in K clusters.

Genetic study of stock structure in North Pacific sei whales

CONCLUSIONSThe present pairwise FST estimates and heterogeneity
tests did not show any signiﬁcant genetic diﬀerentiations
among the three sampling areas for both genetic markers. This was also supported by the STRUCTURE analysis
suggesting a lack of genetic structure of this species.
These ﬁndings implied that the North Paciﬁc sei whale
consists of a single breeding population at least in the pelagic areas surveyed. This inference was consistent withthe comparable genetic diversities, i.e. h, π, HE, among
sampling areas as well as the results from the tests of
HWE and FIS estimates in this study. Kanda et al. (2015b)
suggested that a single stock of sei whale occurs in theentire North Paciﬁc based on genetic and non-genetic
evidence. However, this study did not covered the coastal
areas in both sides of the North Paciﬁc. Additional genetic
samples from the coastal areas are required to conﬁrm
this hypothesis.

ACKNOWLEDGEMENTS
Thanks are due to the researchers and crew membersthat participated in JARPNII and IWC-POWER surveys
for the collection of genetic samples of the sei whales,to Hiroyuki Oikawa and Tomonari Iida (ICR) for theirlaboratory work and to Naohisa Kanda (JANUS-Japan) for
preparing most of the microsatellite data set used in thisstudy.

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Technical Reports of the Institute of Cetacean Research (2019)

pp. 41–51

Technical Report (not peer reviewed)

Distribution of blue, ﬁn, humpback and North Paciﬁc right whalesin the western North Paciﬁc based on JARPN and JARPNII surveys(1994–2014)
Koji Matsuoka* and Takashi Hakamada
Institute of Cetacean Research, 4–5 Toyomi-cho, Chuo-ku, Tokyo 104–0055, Japan*Contact e-mail: matsuoka@cetacean.jp

ABSTRACTThis paper examines the geographical and temporal patterns of distribution of blue, ﬁn, humpback and North
Paciﬁc right whales in the western North Paciﬁc. The analyses were based on sighting data collected systematically by JARPN and JARPNII surveys during May to September in the years 1994–2014. A total of 269,728.1 n.
miles was surveyed in the entire research period. The Density Index (No. of individual whales sighted/100 n.
miles) was calculated and its geographical and temporal (monthly) distribution plotted for each individual species. Fin whale was the species most frequently sighted, followed by humpback, blue and right whales. The
geographical and temporal pattern of distribution was described for each whale species. The large sighting
data set collected systematically by JARPN and JARPNII has made a substantial contribution to understanding
the pattern of geographical distribution and habitat use of whales in the western North Paciﬁc ecosystem.

INTRODUCTION
One of the main sources of sighting data for assessing the
population status of whale species in the western North
Paciﬁc was the JARPN, which was conducted between
1994 and 1999, and its second phase JARPNII conducted
between 2000 and 2014.
The sighting data collected by JARPN and JARPNII havebeen used for studying the distribution pattern and abundance estimation of several large whale species in thewestern North Paciﬁc (Okamura et al., 2001; Matsuoka
et al., 2009). Details of the sighting survey proceduresin JARPN and JARPNII are available in Fujise (2000) andTamura et al. (2009), respectively.
This technical report summarizes the Institute of
Cetacean Research (ICR)ʼs investigation of the pattern of geographical and temporal distribution of blue
(Balaenoptera musculus), ﬁn (B. physalus), humpback(Megaptera novaeangliae) and North Paciﬁc right(Eubalaena japonica) whales in the western North Paciﬁc.
The investigation was based on sighting data collected
systematically by JARPN and JARPNII surveys in the period
1994–2014.

MATERIALS AND METHODS
Research area
The research area comprised the western part of theNorth Paciﬁc, speciﬁcally the International Whaling
Commission (IWC) management sub-areas 7, 8, 9 and
11 (used for management of the common minke whale),north of 35°N, excepting the 200 n.mile EEZʼs of foreigncountries (Figure 1).
Sighting data
Primary sighting and eﬀort data were collected by JARPN(1994–1999) and JARPNII (2000–2014) systematic surveys. Surveys were conducted by sighting and sampling
vessels (SSV) (vessels engaged in sighting and sampling ofwhales) and dedicated sighting vessels (SV) (vessels engaged only in sighting of whales). Sighting data obtainedby SSVs and SVs were combined for the calculation of theDensity Index (see below).
Sighting procedures
The sighting procedures for SSVs and SVs in JARPNII(2000–2014) was not signiﬁcantly changed with regard the procedures in JARPN (1994–1999) with only
some minor changes made (see details in Matsuoka
et al., 2016). The research vessels were equipped with a
top barrel, where three top men conducted sightings. On
the upper bridge, a captain, a gunner, a helmsman anda researcher also conducted the sightings. The sighting
activity was conducted under acceptable weather conditions (see below), from 60 minutes after sunrise to 60
41

Technical Reports of the Institute of Cetacean Research (2019)

Figure 1.

Research area in the western North Paciﬁc indicating the sub-areas used for management of common
minke whale.

minutes before the sunset.
Survey modes
SSV
Searching was conducted under two survey modes: NSC(Normal Search Closing) mode and NSS (Normal Search
Closing Special). The NSC mode corresponds to ʻclosingmodeʼ conducted under the normal weather conditions
deﬁned as visibility of 2 n.miles or more and wind velocity 4 or below. The NSS corresponds to ʻclosing modeʼ
conducted under more unfavorable weather conditions
but under which, the collection of whale samples was
possible (Tamura et al., 2009).
SV
Searching was conducted under two survey modes: ASP
and NSP modes. The ASP mode corresponds to ʻclosingmodeʼ conducted under normal weather conditions deﬁned as visibility of 2 n.miles or more and wind velocity 4
or below. The NSP mode corresponds to ʻpassing modeʼ
conducted under the normal weather conditions deﬁned
above (Matsuoka et al. 2016).
Cruise track design
For the main survey, the zigzag-shaped track line wasestablished to cover the survey area. Furthermore, theʻSpecial Monitoring Survey (SMS)ʼ was adopted in areas
where the density of whales was expected to be high (seeFujise, 2000; Tamura et al., 2009). The vessels conducted
sighting surveys 6 and 4 n.miles apart from each other in42

the main and SMS surveys, respectively. These data werecombined for the analyses.
Conﬁrmation of the sightings
When a sighting was made, the vessels closed the school
immediately in order to identify the species, estimate theschool size and get other biological information such as
the number of calves, estimated body length, etc. Surface temperatures were recorded at the location of eachwhale sighting.
Density Index of Whales
The Density Index of Whales (DIW) (the number of individual whales sighted by 100 n.miles) was calculated
by each Lat.1°× Long.1°grid squares, for each species.
Calculations were made for the entire research period(1994–2014) as well by month. For the calculation sighting data collected by the SSV and SV were combined.

RESULTS AND DISCUSSION
Searching eﬀorts
A total of 269,728.1 n.miles were surveyed in sub-areas
7, 8, 9 and 11 (Figure 1) between 1994 and 2014 (including transit surveys in the Sea of Japan). Figure 2 show the
research area and the primary searching eﬀort (n. miles)
by Lat.1°×Long.1° grid square.
Geographical and temporal distribution pattern ofwhalesTable 1 shows the summary of all primary whale sightings

Distribution of blue, fin, humpback and North Pacific right whales in the western North Pacific based on JARPN and JARPNII surveys (1994–2014)

Figure 2.

The searching eﬀort by each Lat.1°× Long.1° grid square by JARPN and JARPNII surveys during 1994 to 2014
(including transit surveys in the Sea of Japan).

Table 1
Summary of all primary sightings of blue, ﬁn, humpback and North Paciﬁc right whales during the JARPN and JARPNII in the entire
period (1994–2014) including transit surveys to and from the research areas.
SpeciesBlue whale
Fin whale
Humpback whale
N.P. right whale

Indices
Sch.

Ind.

Calf

Mss

DIS

DIW

WT

374
799
492
48

508
1,125
685
68

23
37
42
9

1.36
1.41
1.39
1.42

0.14
0.30
0.18
0.02

0.19
0.42
0.25
0.03

3.0–25.8°C
2.9–26.9°C
2.8–24.1°C
2.7–17.0°C

Sch.: number of the primary sightings of schools; Ind.: number of the primary sightings of individuals; Calf: number of calves;
Mss: mean school size (Ind./Sch.); DIS: Density Index of Schools (schools/100 n.miles); DIW: Density Index of Whales (individual
whales/100 n.miles); WT: range of surface temperature of the species sighting positions.

for blue, ﬁn, humpback and North Paciﬁc right whales inthe entire period (1994–2014), including transit survey in
the Sea of Japan. Fin whale (799 schools/1,125 individuals including 37 calves) was the species most frequently
sighted (DIW: 0.42). Next was the humpback whale (492schools/685 individuals including 42 calves) (DIW: 0.25).
It was followed by the blue whale (374 schools/508 individuals including 23 calves) (DIW: 0.19) and North Paciﬁcright whale (48 schools/68 individuals including 9 calves)(DIW: 0.03).

Pattern of geographical distribution
Figures 3a, 3b, 3c and 3d show the geographical distribution of the DIW of blue, ﬁn, humpback and North
Paciﬁc right whales, respectively, for the entire period(1994–2014).
Blue whale (Figure 3a)Blue whales were widely distributed mainly north of 35°N
in sub-areas 8 and 9 from May to September. Surface
temperature ranged from 3.0°C to 25.8°C (Table 1). A
high-density area was observed north of 45°N, southeast
oﬀ the Kamchatka Peninsula in sub-area 9.
43

Technical Reports of the Institute of Cetacean Research (2019)44

Figure 3a.

Distribution of DIW of blue whales by Lat.1°× Long.1° grid squares. The DIW was calculated using JARPN
and JARPNII sighting data in the entire period (1994 to 2014).

Figure 3b.

Distribution of DIW of ﬁn whales by Lat.1°× Long.1° grid squares. The DIW was calculated using JARPN
and JARPNII sighting data in the entire period (1994 to 2014).

Distribution of blue, fin, humpback and North Pacific right whales in the western North Pacific based on JARPN and JARPNII surveys (1994–2014)

Figure 3c.

Distribution of DIW of humpback whales by Lat.1°×Long.1° grid squares. The DIW was calculated using
JARPN and JARPNII sighting data in the entire period (1994 to 2014).

Figure 3d.

Distribution of DIW of North Paciﬁc right whales by Lat.1°×Long.1° grid squares. The DIW was calculatedusing JARPN and JARPNII sighting data in the entire period (1994 to 2014).

45

Technical Reports of the Institute of Cetacean Research (2019)Blue whales were caught in the past around the rim of
the western North Paciﬁc. In summer, they concentrated
along the edge of the continental shelf and along thesouth side of the Aleutian Archipelago. The catch data
showed a distribution gap between sub-areas 7 and 9
in summer (Nishiwaki, 1966). However, JARPNII data
showed no such gap. The previous gap may have beencaused by regulation of the whaling operations between
coastal (land base type) and oﬀshore (mother ship type)whaling. Further, according to sighting data collected by
the Japanese Scouting Vessel (JSV) between 1966 and1990, blue whales were not sighted in sub-areas 7, 8 and
9 in June. However, JARPN and JARPNII sighting data suggested that this species was widely distributed in thosesub-areas in June in the period 1994–2014.
The design-based abundance of this species in subareas 7, 8 and 9 was estimated as 38 whales during May
to June (2009) and as 958 whales during July to August(2008) (Hakamada and Matsuoka, 2016).
Fin whale (Figure 3b)
Fin whale was the most frequently sighted species. This
species was mainly sighted in sub-areas 8 and 9, and the
distribution pattern was similar to that of the blue whale.
They were mainly distributed north of 37°N in sub-areas
7, 8 and 9 from May to September. Surface temperature
ranged from 2.9°C to 26.9°C (Table 1). A high-density area
was observed north of 45°N in sub-area 9.
Fin whales were caught in the past along the outer
shelf and south of the Aleutian Islands. A distribution gap
between sub-areas 7 and 9 was previously observed forthis species in summer (Nishiwaki, 1966). However, as in
the case of the blue whale, the present results showedno such gap. The previous gap may have been causedby regulation of the whaling operations between coastal(land base type) and oﬀshore (mother ship type) whaling.
The design-based abundance of this species in subareas 7, 8 and 9 was estimated as 413 whales during May
to June (2009) and as 3,958 whales during July to August(in 2008) (Hakamada and Matsuoka, 2016).
Humpback whale (Figure 3c)
Humpback whales were mainly distributed north of 37°N
in sub-areas 7, 8 and 9 from May to September. Surface
temperature ranged from 2.8°C to 24.1°C (Table 1). Highdensity areas were observed north of 35°N in sub-areas 7
and 8, and north of 45°N in sub-area 9.
The design-based abundance of this species in subareas 7, 8 and 9 was estimated as 1,136 whales during
May–June (2009) and as 392 whales during July–August46(2008) (Hakamada and Matsuoka, 2016).
North Paciﬁc right whale (Figure 3d)
North Paciﬁc right whale was the least frequently sighted
species. This species was mainly distributed north of 37°N
in sub-areas 7, 8 and 9 from May to September. Surface
temperature ranged from 2.7°C to 17.0°C (Table 1).
According to Miyashita et al. (1995), there were nosightings in waters outside of the Okhotsk Sea, north of
40°N. However, present results conﬁrmed the existenceof this species in the oﬀshore region during 1994–2014
from May to September.
The design-based abundance of this species in subareas 7, 8 and 9 was estimated as 1,147 whales during
May–June (2011–2012) and 416 whales during July–August (2008) (Hakamada and Matsuoka, 2016).
Pattern of temporal distribution
A more detailed description of the monthly distributionof the species is presented here based on Figures 4a, 4b,4c and 4d, which show the monthly changes in the density index of blue, ﬁn, humpback and North Paciﬁc rightwhales, respectively. As a whole, the main distribution ofblue, ﬁn, humpback and North Paciﬁc right whales moved
northward from 35°N to 45°N from May–August, whichcoincided with the results of previous large-scale distribution pattern reported by Miyashita et al. (1995).
Blue whale (Figure 4a)
A northward migration pattern was observed for this species. The main distribution from 35°N to 40°N in May toJune moved north of 40°N in July to August in sub-areas
8 and 9.
Fin whale (Figure 4b)
A northward migration pattern of ﬁn whale was also observed. The main distribution from 35°N to 40°N during
May–June moved north of 40°N during July–August in
sub-areas 8 and 9. There were almost no ﬁn whale sightings in the west of 144°E in June, and west of 150°E in
July.
Humpback whale (Figure 4c)
A northward migration pattern of humpback whales was
also observed. The main distribution from 37°N to 43°N
in sub-area 7 during May to June moved to north of 45°N
during July–August in sub-areas 8 and 9.
The present results revealed that the distribution
pattern of this species changed from that reported inprevious studies. Humpback whales were not sighted inDistribution of blue, fin, humpback and North Pacific right whales in the western North Pacific based on JARPN and JARPNII surveys (1994–2014)

Figure 4a.

Monthly change of DIW of blue whales during JARPN and JARPNII from 1994 to 2014 surveys, by Lat.1°×Long.1°square.
Top left: April; Top right: May; Middle left: June; Middle right: July; Bottom left: August; Bottom right: September.

sub-areas 7 and 8 in May and June by the JSV surveys(1966–1990), however they were present in those subareas and period by the JARPN and JARPNII surveys in
1994–2014.
North Paciﬁc right whale (Figure 4d)
A northward migration pattern of this species was observed. The main distribution area was north of 42°N dur-ing July to August in sub-area 9. The distribution patternof this species was reported using historical catch and JSV
data (Omura, 1986; Miyashita and Kato, 1998; Clapham
et al., 2004). The present results conﬁrm the existenceof this species in sub-areas 7, 8 and 9 during 1994–2014,
and the distribution pattern in May–September is similar
to that reported previously.
There are two migration routes along both sides of the47

Technical Reports of the Institute of Cetacean Research (2019)

Figure 4b.

Monthly change of DIW of ﬁn whales during JARPN and JARPNII from 1994 to 2014 surveys by Lat.1°× Long.1°square. Top
left: April; Top right: May; Middle left: June; Middle right: July; Bottom left: August; Bottom right: September.

Japanese main Island, based on historical whaling data
(Omura, 1986). Several scientists have suggested that the
Kuril Islands and Kamchatka coasts are likely to be major
summer feeding regions, based on historical and recent
new information (Matsuoka et al., 2009; Brownell et al.,
2001; Clapham et al., 2004; Sekiguchi et al., 2014). A
northward migration pattern was also observed from the
Paciﬁc to the Sea of Okhotsk during the winter to summer
48

in recent analyses using Japan and Russian sighting data
(Matsuoka et al., 2018).

CONCLUSIONS
Sighting data of large whales in the western North Paciﬁc,collected systematically by JARPN and JARPNII for a long
period of time, were valuable in providing information on
the geographical and temporal pattern of distribution of

Distribution of blue, fin, humpback and North Pacific right whales in the western North Pacific based on JARPN and JARPNII surveys (1994–2014)

Figure 4c.

Monthly change of DIW of humpback whales during JARPN and JARPNII from 1994 to 2014 surveys by
Lat.1°×Long.1°square. Top left: April; Top right: May; Middle left: June; Middle right: July; Bottom left: August; Bottom
right: September.

blue, ﬁn, humpback and North Paciﬁc right whales in thisoceanic basin. The data indicate that some species havebeen expanding their distribution in recent years. The
same sighting data have been used for abundance estimates of these species, however, future studies on distribution and abundance should take into consideration theavailable information on stock structure.

ACKNOWLEDGEMENTS
We thank all cruise leaders, captains, oﬃcers, crew andresearchers involved on the JARPN and JARPNII surveys
for their eﬀort to collect sighting data.

49

Technical Reports of the Institute of Cetacean Research (2019)

Figure 4d.

Monthly change of the Density Index (number of primary sightings of whales/100 n.mile) of North Paciﬁc right whales
during JARPN and JARPN II from 1994 to 2014 surveys by Lat.1°× Long.1°square. Top left: April; Top right: May; Middle
left: June; Middle right: July; Bottom left: August; Bottom right: September.

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[Available from the IWC Secretariat].
Nishiwaki, M. 1966. Distribution and migration of the larger cetaceans in the North paciﬁc as shown by Japanese whaling results. pp. 171–191. In: K.S. Norris (ed.) Whales, dolphins, andporpoises. University of California Press, Berkely. CA. 789 pp.
Okamura, H., Matsuoka, K., Hakamada, T., Okazaki, M. andMiyashita, T. 2001. Spatial and temporal structure of thewestern North Paciﬁc minke whale distribution inferred fromJARPN sightings data. J. Cetacean Res. Manage. 3: 193–200.
Omura, H. 1986. History of right whale catches in the waters
around Japan. Rep. int. Whal. Commn (special issue) 10:
35–41.
Sekiguchi, K., Ohnishi, H., Sasaki, H., Haba, S., Iwahara, Y.,
Mizuguchi, D., Otsuki, M., Saijo, D., Nishizawa, B., Mizuno, H.,
Hoshi, N. and Kamito, T. 2014. Sightings of the western stockof North Paciﬁc right whales (Eubalaena japonica) in thefar southeast of the Kamchatka Peninsula. Marine Mammal
Science 30 (3): 1199–1209.
Tamura, T., Matsuoka, K. and Fujise, Y., 2009. Methodology
and survey procedure under the JARPNII—oﬀshore component—with special emphasis on whale sampling procedures.
Paper SC/J09/JR4 presented to the JARPNII Review Meeting,January 2009 (unpublished). 16 pp. [Available from the IWC
Secretariat].

51

Technical Reports of the Institute of Cetacean Research (2019)

pp. 52–54

Technical Report-Note (not peer reviewed)

The platform and equipment for satellite-monitored tagging
experiments in NEWREP-A and NEWREP-NP
Kenji Konishi* and Tatsuya Isoda
Institute of Cetacean Research, 4–5 Toyomi-cho, Chuo-ku, Tokyo 104–0055, Japan*Contact e-mail: konishi@cetacean.jp
In recent years, satellite monitored tags have been recognized as crucial tools for behavioural studies of wild
animals. These tools have been used for monitoring
movement patterns of free-ranging animals such as marine mammals and sea turtles (e.g. Hoenner et al., 2012;
Mclntyre, 2014; Lee et al., 2017). However, the attachment of the tags on the body of large whales is a challenging issue, as attachment of the tag needs to be made frommoving vessels on moving whales.
Recently satellite tags housed in stainless steel and airpressured tagging guns have been used successfully for the
long-term tracking of large whales to investigate their migration routes (e.g. Kennedy et al., 2014; Garrigue et al., 2015;
Panigada et al., 2017). From the analysis of time series location data, the changes of movement speed and the swimming angle can be calculated, and the latest modelling approach enables the deﬁnition of behaviour of the animals,
such as foraging or migrating (Jonsen et al., 2005; 2013; Silva
et al., 2013; 2014; Prieto et al., 2014; Dulau et al., 2017).
Satellite tracking of baleen whales was part of the objectives of NEWREP-A and NEWREP-NP, and the Instituteof Cetacean Research (ICR) have been working on thedevelopment of tags, and attachment systems to be usedfrom the platform of large vessels. This paper reports on
the platform and instruments of the satellite monitored
tagging experiments conducted during NEWREP-A and
NEWREP-NP surveys including a description of the tags,
the attachment system and the vessels from where theexperiments were conducted. Results of the experiments
will be summarized in future TEREP-ICR issues.

triangle stop plate; Wildlife Computers Inc.) (Figure 1).
SPOT177 was designed to track the positions of thewhales. The anchor was designed by ICR (ca. 100 mm in
ISOD-type ver.2) for stabilizing the tags at implantation,and it was screwed on the anterior of the tag-housing(Figure 1 and 2). The penetration into the body was almost 200 mm (from the stopper at the end of tags to the

Figure 1.

Satellite monitored tag SPOT177 (Wildlife Computers
Inc.)

Figure 2.

The anchors designed by the ICR for SPOT type tags.

Satellite monitored tags
The ICR used the so-called Type C tags. The anchoring
systems and electronic packages are consolidated andembedded in the body of the animals with an external antenna (IWC, NOAA and ONR, 2019). This Type C tags havebeen used for relatively large whales. Geographical locations are obtained by satellite transmissions, such as Argos
system operated by Collected Localisation Satellite (CLS).
Speciﬁcally the ICR used the SPOT177 tags (113 mm with52

The platform and equipment for satellite-monitored tagging experiments in NEWREP-A and NEWREP-NP

tip of the anchor). The ending part of the tag was connected to a pipe-like LK-Carrier (made of polycarbonate
designed by LK-ARTS, Skutvik, Norway) (Figure 3) with atiming release, and inserted into the barrel of the Airgun.
LK-Carrier also works as a ﬂoat in case deployment failure
occurs at sea. The anchors and tags were sterilized before
their use. Once deployment was conﬁrmed as successful,a saltwater sensor activated the tag that started transmitting when the dry switch sensor surfaced.

AirgunThe Air Rocket Transmitting System (LK-ARTS), which wasdeveloped by Lars Kleivane in cooperation with RestechNorway, was used for launching the tags in NEWREP-A
and NEWREP-NP (Figure 4). LK-ARTS is designed to launchsatellite tags, sensor packages, biopsy darts etc. by com-

Figure 3.

A set for SPOT177 attachment. Anchor, tag and LKCarrier are connected.

Figure 4.

pressed air. The entire body is made of alumite and thebarrel (launching tube) and the posterior stock (shoulder support) are detachable, so that the length can bechanged depending on the tag shapes. Total length is approximately 1,350 mm with a 780 mm launching tube. An
optical sight and a pressure manometer are connected.
The air cylinder with hose is connected to the valve of the
LK-ARTS in the Figure 4. Air pressure is easily controlled
by the valve on the base. This allows shooting at diﬀerent
distances.

Vessels
The tags were deployed from the bow deck (6.5 m heightfrom sea surface) of the R/V Yushin-Maru-type vessels(ca.720 GT) with length of about 70 m (Figure 5). The useof this type of vessels has the advantage of being able toconduct tag attachments far from shore and under roughsea condition. In parallel to tagging, skin biopsies werealso collected from the same individual whales for genetic analyses using a Larsen gun system (Larsen, 1998).
During the tagging experiments, the part of the whale
body where the tags were attached was recorded (Figure 6). Also, photos of the attached tags were taken to in-

The Air Rocket Transmitting System (LK-ARTS) launching system.

Figure 5.

Yushin-Maru-type vessel and its bow deck.
53

Technical Reports of the Institute of Cetacean Research (2019)

Figure 6.

Code of whale body area used for recording thelocation of tags deployment.

vestigate the relationship between the depth of penetration and the radio transmissions for modiﬁcation of theanchor and improvement of the attachment techniques.

Target whale species
The platform and equipment described in this note havebeen used in all NEWREP-A (2015/16–2018/19) and
NEWREP-NP (2017–2019) survey years. The satellitemonitored tags were deployed on the Antarctic minke
whales in the Indo-Paciﬁc region of the Antarctic, and oncommon minke, sei, ﬁn and blue whales in the western
North Paciﬁc. The tracking results will be reported in future TEREP-ICR issues.

ACKNOWLEDGEMENTS
We thank Lars Kleivane, Shingo Minamikawa andShigetoshi Nishiwaki for providing technical advice on thedevelopment and implementation of tagging equipment.
Thanks are also due to the crews on board of the vessels
for their assistance during the ﬁeld works.

REFERENCES
Dulau, V., Pinet, P., Geyer, Y., Fayan, J., Mongin, P., Cottarel, G.,
Zerbini, A. and Cerchio, S. 2017. Continuous movement behavior of humpback whales during the breeding season in thesouthwest Indian Ocean: on the road again! Mov. Ecol. 5: 11.
Garrigue, C., Clapham, P.J., Geyer, Y., Kennedy, A.S. and Zerbini,
A.N. 2015. Satellite tracking reveals novel migratory patterns
and the importance of seamounts for endangered South
Paciﬁc humpback whales. R. Soc. Open Sci. 2: 150489.
Hoenner, X., Whiting, S.D., Hindell, M.A. and Mcmahon, C.R.
2012. Enhancing the use of argos satellite data for homerange and long distance migration studies of marine animals.
PLoS ONE 7: 1–10.
International Whaling Commission, U.S. National Oceanic

54

and Atmospheric Administration and U.S. Oﬃce of Naval
Research. 2019. Report of the Joint U.S. Oﬃce of Naval
Research, International Whaling Commission and U.S.
National Oceanic and Atmospheric Administration Workshop
on Cetacean Tag Development, Tag Follow-up and Tagging
Best Practices. Paper SC/68a/Rep03 presented to the IWC
Scientiﬁc Committee, April 2019 (unpublished). 35 pp.
[Available from the IWC Secretariat].
Jonsen, I.D., Flemming, J.M. and Myers, R.A. 2005. Robust
State-Space Modeling of Animal Movement Data. Ecology 86:
2874–2880.
Jonsen, I.D., Basson, M., Bestley, S., Bravington, M.V., Patterson,
T.A., Pedersen, M.W., Thomson, R., Thygesen, U.H. andWotherspoon, S.J. 2013. State-space models for bio-loggers:
A methodological road map. Deep-Sea Res Part II. 88–89:
34–46.
Kennedy, A.S., Zerbini, A.N., Rone, B.K. and Clapham, P.J. 2014.
Individual variation in movements of satellite tracked humpback whales Megaptera novaeangliae in the Eastern AleutianIslands and Bering Sea. Endang Species Res 23: 187–195.
Larsen, F. 1998. Development of a biopsy system primarily for use
on large cetaceans. Paper SC/50/O15 presented to the IWC
Scientiﬁc Committee, April 1998 (unpublished). 9 pp. [Available
from the IWC Secretariat].
Lee, J.F., Friedlaender, A.S., Oliver, M.J. and DeLiberty, T.L.
2017. Behavior of satellite-tracked Antarctic minke whales(Balaenoptera bonaerensis) in relation to environmental
factors around the western Antarctic Peninsula. Anim.
Biotelemetry 5: 23.
Mclntyre, T. 2014. Biologging and marine mammals review bibliography. African J. Mar. Sci. 36: 71–85.
Panigada, S., Donovan, G.P., Druon, J.N., Lauriano, G.,
Pierantonio, N., Pirotta, E., Zanardelli, M., Zerbini, A.N. anddi Sciara, G.N. 2017. Satellite tagging of Mediterranean ﬁnwhales: Working towards the identiﬁcation of critical habitats
and the focussing of mitigation measures. Sci. Rep. 7: 1–12.
Prieto, R., Silva, M., Waring, G. and Gonçalves, J. 2014. Sei whale
movements and behaviour in the North Atlantic inferred fromsatellite telemetry. Endang Species Res 26: 103–113.
Silva, M.A., Prieto, R., Jonsen, I., Baumgartner, M.F. and Santos,
R.S. 2013. North Atlantic blue and ﬁn whales suspend theirspring migration to forage in middle latitudes: building up
energy reserves for the journey? PLoS ONE 8: e76507.
Silva, M.A., Jonsen, I., Russell, D.J.F., Prieto, R., Thompson,
D. and Baumgartner, M.F. 2014. Assessing performance ofBayesian state-space models ﬁt to Argos satellite telemetry locations processed with kalman ﬁltering. PLoS ONE 9:e92277.

Technical Reports of the Institute of Cetacean Research (2019)

pp. 55–58

Commentary
The views expressed here are those of the author and do not necessarily reﬂect the views of the Institute of
Cetacean Research

Withdrawal of Japan from the International Convention for
the Regulation of Whaling: implications for the whale research
conducted by the Institute of Cetacean Research
Luis A. Pastene**Contact e-mail: pastene@cetacean.jp

INTRODUCTION
On 26 December 2018, Japan announced its withdrawal
from the International Convention for the Regulation of
Whaling (ICRW), which came into eﬀect on 30 June 2019.
From this same date Japan ceased its two whale research
programs under special scientiﬁc permit conductedunder Article VIII of the ICRW, the NEWREP-A (New Scientiﬁc Whale Research Program in the Antarctic Ocean) andthe NEWREP-NP (New Scientiﬁc Whale Research Programin the western North Paciﬁc). From 1 July 2019, Japan
started commercial whaling on common minke, Brydeʼs
and sei whales within its territorial sea and Exclusive Economic Zone (EEZ).
As reported by Tamura et al. (2017), the Institute of
Cetacean Research (ICR) was in charge of designing andimplementing both NEWREP-A and NEWREP-NP, and research under these two programs was the main and ﬁrst
priority of the ICR. Now that these research programs
have ceased, what is the future of the ICR and its researchon whales? This note attempts to respond to this question.
This authorʼs view is that the basis for responding to
the question above can be found i) in the statement fromJapan at the International Whaling Commission Scientiﬁc Committee (IWC SC) in 2019 regarding Japanʼs withdrawal from the IWC; and ii) in Japanʼs research activities
aimed to calculate sustainable catch limits for commercial
whaling in its EEZ.

STATEMENT FROM JAPAN AT THE IWC SCIENTIFICCOMMITTEE REGARDING JAPANʼS WITHDRAWALFROM THE IWC
At the 2019 annual meeting of the IWC SC, Japan made astatement regarding its future involvement in the work of
the IWC SC (IWC, 2019). The main points of the statement
are summarized below:• Japan will continue research programs with non-lethal methods in both the North Paciﬁc and theAntarctic Ocean.
• Japan will collect ﬁsheries-dependent scientiﬁcdata through commercial whaling within its EEZ.
• Japan will provide the IWC SC scientiﬁc ﬁndings derived from the activities described above.
• Japan will provide the IWC SC standard statistics inrelation to its commercial whaling.
• As for the data collected through its special permit programs (JARPA/JARPAII, NEWREP-A, JARPN/
JARPNII, NEWREP-NP), Japan will continue to beengaged in their analyses and provide the IWC SC
with scientiﬁc ﬁndings thereon.
• Japan will continue to provide information on its
DNA register for large whales on a voluntary basis.
• Japan is prepared to continue the IWC-POWER (Paciﬁc Ocean Whale and Ecosystem Research) in the
North Paciﬁc.
Given their previous experience with NEWREP-A and
NEWREP-NP, this author considers that ICR scientists
have the potential to play a substantial future role in the
research activities listed above.

CATCH LIMIT CALCULATION FOR SUSTAINABLE
WHALING IN THE WESTERN NORTH PACIFIC
In its IWC SC statement, Japan noted that catch limits ofcommon minke, Brydeʼs and sei whales will be calculated
in line with the Revised Management Procedure (RMP),
ʻtaking into account relevant scientiﬁc progress achievedby the IWC SC such as outputs from Implementation
Reviews and In-depth Assessment.ʼ While such scientiﬁcprogress should be taken into account, Japanʼs withdrawal from the ICRW means that it is now the sole mandate
and responsibility of Japan to calculate sustainable catch
limits for the target whale species in the western North
Paciﬁc, and to allocate such quotas internally within
Japan.
In fact, Japan established an ad-hoc domestic group55

Technical Reports of the Institute of Cetacean Research (2019)

composed of scientists from several Japanese researchorganizations and oﬃcials from the Fisheries Agency ofJapan (FAJ) with the aim to carrying out the calculationsof catch limits of common minke, Brydeʼs and sei whales
in line with the RMP. The main work of the ad-hoc groupwas:i) to summarize the key information on stock structure (required to deﬁne management areas),abundance and catch history of the three speciesof baleen whales;ii) to run the Norwegian Catch Limit Algorithm (CLA)
computer code for a tuning level of 0.6;iii) to investigate the robustness of the catch limits
calculated by the CLA to some uncertainties by theso-called Implementation Simulation Trials (ISTs)
process (in the case of common minke and Brydeʼswhales where stock structure is complex).
The ﬁnal catch quotas were determined by the FAJ
after the calculations of catch limits by the domestic
ad-hoc group were reviewed by a team of international
experts. Based on those catch quotas, which were lower
than the calculated catch limits, commercial whaling operations started from 1 July 2019 in Japanʼs EEZ. Participation of ICR scientists was key in the successful work of the
ad-hoc group.
Japanʼs work on catch limits (including the ISTs) willcontinue to be based on the best available science;
hence, the catch limits will be revised from time to time
to reﬂect the latest scientiﬁc information. In this context,
a domestic Steering Group was recently established todeal with the required data and analyses associated with
future updates of the calculations of catch limits. The
Terms of References (TORs) of this Steering Group involve
among others, i) the identiﬁcation of relevant input data
to update the catch limit calculations in line with the RMP(i.e. abundance estimates, genetic and non-genetic datafor reﬁning the current stock structure hypotheses, etc.);ii) the identiﬁcation of biological data (i.e. age, reproductive data) and the process required to improve/optimize
the use of the current RMP and; iii) the research of alternative management procedures to the RMP.
This author considers that, given the contribution andexperience acquired by ICR scientists during the work of
the previous ad-hoc group, the contribution of ICR scientists to the work of the new Steering Group would remain
substantial.

IMPLICATIONS FOR THE WHALE RESEARCH CONDUCTED BY THE ICR
From the points made in Japanʼs statement at the IWC
56

SC and the TORs and activities proposed for the domestic
Steering Group on sustainable whaling in the western
North Paciﬁc it is possible to highlight some research activities relevant for the future work of the ICR.
1.

Research programs with non-lethal methods inboth the North Paciﬁc and the Antarctic Ocean
Japan presented the outline of a new research program in
the Indo-Paciﬁc region of the Antarctic at the 2019 IWC SC(GOJ, 2019a) and at the Convention on the Conservationof Antarctic Marine Living Resourcesʼs Working Group on
Ecosystem Monitoring and Management (CCAMLR EMM)
(GOJ, 2019b) meetings. The research program, called
JASS-A (Japanese Abundance and Stock structure Surveys
in the Antarctic), has two main research objectives i) the
study of the abundance and abundance trends of large
whale species, and ii) the study of the distribution, movement and stock structure of large whale species. JASS-A
also has several secondary research objectives related
to oceanographic conditions, marine debris and whale
biology. The research program will be based on systematic sighting surveys utilizing the line transect method, tobe conducted alternatively in IWC Areas III, IV, V and VI,
south of 60°S by one or two specialized vessels, during atentative period of eight austral summer seasons. Analyses related to main and secondary objectives will be conducted based on new as well previous data collected by
JARPA/JARPAII and NEWREP-A in the same research area.
In the western North Paciﬁc, dedicated sighting surveys are being planned with the aim of obtaining sighting
data for abundance estimation of large whale species,
with emphasis given to common minke, Brydeʼs and sei
whales, the species that are the current target of commercial whaling. Also the surveys will collect biopsy
samples, which are important for genetic analyses to
elucidate/reﬁne stock structure hypotheses.
Surveys of the IWC-POWER program have been conducted successfully until 2019. Japan in consultation with
the IWC should decide on the survey plan for 2020, andon the future of the POWER after 2020. The importanceof such surveys is that they provide sighting data (andbiopsy samples) from areas not covered by the Japanese
dedicated sighting surveys.
The ICR could play a key role in the research activities
based on non-lethal methods given the substantial experience of its scientiﬁc staﬀ in both ﬁeld sighting surveys
and in analytical procedures related to abundance estimates and stock structure research.

Withdrawal of Japan from the International Convention for the Regulation of Whaling

2.

Collection of ﬁsheries-dependent scientiﬁc data
through commercial whaling
Japanese scientists have already identiﬁed the dataand samples to be collected during commercial whaling
operations. The data involve data/samples relevant for
applying/optimizing the RMP as explained above (genetic
samples for stock structure analyses, biological samples
for age and reproductive status determination), andother data/samples for more generic use.
As is the case for non-lethal research noted above, ICR
scientists also have substantial experience in collecting
data and biological samples during past whale research
programs under special permit. To keep consistency andthe quality of the sampling process, ICR scientists should
be involved in sampling during commercial whaling operations in collaboration with scientists from the National
Research Institute of Far Seas Fisheries and government
inspectors.

of the Steering Group in areas of their expertise such as, i)the design of dedicated sighting surveys; ii) the estimatesof abundance; iii) collection and analyses of genetic
samples to reﬁne the information on stock structure of
the key species; and iv) running the CLA and designing/
implementing the ISTs.
Data accumulated by the ICR through its previous
whale research programs are likely to play a key role in
the process. Data available involve not only those key
for the application of the current RMP (stock structure,abundance, and catch history) but also some biological
data such as age and reproductive status, which can beused for the improvement or optimization of the current
RMP, and for developing of new catch limit calculation
methods.

3.

Japan will have observer status for its future participation in the work of the IWC SC. As usual, ICR scientists
should continue participating in the annual meetings andintersessional workshops of the IWC SC either as part ofJapanʼs observer delegation or as Invited Participants.
Following domestic consultation, ICR scientists may present results of the analyses mentioned above to the annual meetings.
ICR scientists have been engaged in meetings of otherinternational organizations related to the conservationand management of marine living resources i.e. in meetings of the North Atlantic Marine Mammal Commission
Scientiﬁc Committee (NAMMCO SC), CCAMLRʼs working groups, North Paciﬁc Marine Science Organization(PICES), etc. Their future participation in these international fora should be encouraged.

Analyses of data and samples from previous whale
research programs under special permit
In the case of the Antarctic the analyses by JASS-A under
its main and secondary objectives will be conducted onpooled data with those data/samples collected by JARPA/
JARPAII and NEWREP-A. The analyses of pooled data willcontribute with important information not only for theassessment of several large whale species but also forstudies on the ecosystem.
The analyses of samples and data obtained by JARPN,
JARPNII and NEWREP-NP in the western North Paciﬁc will
be continued, and those analyses should be conductedin conjunction with data and samples collected duringcommercial whaling operations. In this case emphasisshould be given to analyses relevant for assessment andmanagement of common minke, Brydeʼs and sei whales.
Because the whale research programs under special
permit were designed and implemented by the ICR, it isnatural to assume that the ICR would play an importantrole in this particular research activity in the future.
4. DNA registry of large whales
Given the expertise and accumulated experience, the ICR
should continue developing and implementing the DNA
registry of large whales for monitoring of the domestic
market under the supervision of the FAJ. Technical updates of the registry should be presented by the ICR to
the annual meetings of the IWC SC on a voluntary basis.
5. Catch limit calculations for sustainable whaling
ICR scientists have the potential to contribute to the work

FUTURE RELATIONSHIP BETWEEN JAPAN AND
THE IWC SCIENTIFIC COMMITTEE AND OTHER
RESEARCH ORGANIZATIONSCONCLUSIONThe ICR and its scientists can play an important role in
the future whale research activities of Japan. The basis
for this conclusion are given in the research plans andguidelines outlined at Japanʼs statement regarding its
withdrawal from the IWC, and on the TORs of the recently
established Steering Group on sustainable commercial
whaling in Japanʼs EEZ. This conclusion is not surprising
given the ICRʼs substantial accumulated experience ofapproximately 30 years investigating whales and theirecosystem in both the Antarctic and the western North
Paciﬁc. The ICR scientists have the ﬁeld and analyticalexpertise (based on lethal and non-lethal methods) tocontinue responding to biological and ecological ques57

Technical Reports of the Institute of Cetacean Research (2019)

tions on whales, and contribute in this way to the futureconservation and management of this group of animals.

REFERENCES
Government of Japan. 2019a. Outline of a research program
to investigate the abundance, abundance trends and stock
structure of large whales in the Indo-Paciﬁc region of the
Antarctic, including a survey plan for the 2019/20 australsummer season. Paper SC/68a/ASI08 presented to the
IWC Scientiﬁc Committee, May 2019 (unpublished). 16 pp.
[Available from the IWC Secretariat].
Government of Japan. 2019b. Outline of a research program
to investigate the abundance, abundance trends and stock

58

structure of large whales in the Indo-Paciﬁc region of the
Antarctic, including a survey plan for the 2019/20 australsummer season. Paper WG-EMM-2019/68 presented to
the CCAMLR Working Group on Ecosystem Monitoring andManagement, July 2019 (unpublished). 16 pp.
International Whaling Commission. 2019. Report of the
Scientiﬁc Committee. Annex U: Statement from Japan regarding Japanʼs withdrawal from the IWC: https://archive.iwc.int/
pages/search.php?search=!collection73&bc_from=themes.
Tamura, T., Matsuoka, K. and Pastene, L.A. 2017. An overview
of the research programs on large whales conducted by
the Institute of Cetacean Research. Technical Reports of theInstitute of Cetacean Research (TEREP-ICR) No. 1: 1–14.

Technical Reports of the Institute of Cetacean Research (2019)

pp. 59–62

International meetings

Participation of scientists of the Institute of Cetacean Research inInternational Meetings in 201934th International Symposium on the Okhotsk
Sea & Polar Oceans, 2019The Okhotsk Sea & Polar Oceans Symposium is organizedannually by the City of Mombetsu. This symposium promotes the advancement of all ice-related studies including biology and ﬁsheries, in the Sea of Okhotsk.
The 2019 symposium was held at the Mombetsu
Culture Hall, Mombetsu, Hokkaido, Japan from 17 to 20
February. Two scientists from the Institute of Cetacean
Research (ICR) (Kato and Tamura) participated in the symposium by presenting an ʻOutline of the second whale
scientiﬁc permit survey oﬀ the coast of the Okhotsk Sea
under the NEWREP-NP program.ʼ

documents at the Ad hoc Working Group on Abundance
Estimates, Stock Status and International Cruises, two
documents at the Working Group on Ecosystem Modelling, two documents at the Working Group on Environmental Concerns, one document at the Working Groupon Stock Deﬁnition and DNA Testing, and two documents
at the Sub-Committee on Other Southern Hemisphere
Whale Stocks.
The report of the IWC SC meeting can be found in thewebsite of the IWC (https://iwc.int/home).

Safari Park Hotel & Casino, Nairobi, Kenya.

Mombetsu Culture Hall, Mombetsu, Japan.

Annual meeting of the International Whaling
Commission Scientiﬁc Committee (IWC SC)
The International Whaling Commission (IWC) is an international body set up by the terms of the International
Convention for the Regulation of Whaling (ICRW), which
was signed in Washington, D.C., United States, on 2 December, 1946 to ʻprovide for the proper conservation ofwhale stocks and thus make possible the orderly development of the whaling industry.ʼ One of the importantcomponents of the IWC is the Scientiﬁc Committee (SC),which meets annually.
The 2019 meeting of the IWC SC was held at the Safari Park Hotel & Casino, Nairobi, Kenya from 10 to 23
May. A total of ten scientists from the ICR participated in
the meeting (Fujise, Kato, Pastene, Tamura, Matsuoka,
Goto, Hakamada, Yasunaga, Taguchi and Takahashi).
They presented ﬁve documents at plenary sessions, ﬁve

In 2019, ICR scientists also participated in the FirstIntersessional Workshop on the Implementation Review
for western North Paciﬁc common minke whales, held at
the Fisheries Agency of Japan (FAJ)ʼs Crew House, Tokyo,
Japan from 25 February to 1 March. Pastene, Goto, Hakamada, Taguchi, Inoue and Takahashi from the ICR participated in the workshop
The report of this meeting can be found in the websiteof the IWC (https://iwc.int/home).

Annual meeting of the Convention on the Conservation of Antarctic Marine Living Resources—
Working Group on Ecosystem Monitoring andManagement (CCAMLR-EMM)
The Convention on the Conservation of Antarctic Marine
Living Resources (CCAMLR) is part of the Antarctic Treaty
System. The Convention was opened for signature on
1 August 1980 and entered into force on 7 April 1982
thereby establishing the Commission for the Conservation of Antarctic Marine Living Resources. The goal is topreserve marine life and environmental integrity in and59

Technical Reports of the Institute of Cetacean Research (2019)near Antarctica. It was established in large part in response to concerns that an increase in krill catches in theSouthern Ocean could have a serious impact on populations of other marine life which are dependent upon krill
for food. The CCAMLR has a Scientiﬁc Committee andseveral Working Groups including the Working Group on
Ecosystem Monitoring and Management (EMM), whichmeet annually.
The 2019 meeting of the CCAMLR-EMM was held at
the Concarneau Marine Station, Concarneau, France
from 24 June to 5 July. One scientist from ICR participatedin the meeting (Pastene). He presented the documents
ʻDistribution and possible areas of spatial mixing of two
stocks of humpback whales, a krill predator, in the IndoPaciﬁc region of the Antarctic revealed by genetic analysesʼ and ʻOutline of a research program to investigate
the abundance, abundance trends and stock structure oflarge whales in the Indo-Paciﬁc region of the Antarctic,
including a survey plan for the 2019/20 austral summer
season.ʼ The presentations of these documents weremade under the agenda item ʻKrill predator biology, ecology and population dynamics.ʼ
The report of the meeting can be found in the websiteof the CCAMLR (https://www.ccamlr.org/).

Agriculture and Consumer Protection, Economic andSocial Development, Fisheries and Aquaculture, Forestry,
Corporate Services, Human Resources and Finance andTechnical Cooperation.
The Expert Meeting to ʻDevelop technical guidelines toreduce bycatch of marine mammals in capture ﬁsheriesʼ
was held at the FAO headquarters in Rome, Italy on 17-19
September 2019. Twenty-nine ﬁsheries and bycatch experts and observers from FAO Members participated in
the Meeting: Argentina, Australia, Brazil, Canada, Chile,
Denmark, Iceland, Japan, Norway, Russian Federation,
Sweden, and the United States of America. The meeting
was also attended by experts from various regional andinternational organizations: Convention on the Conservation of Migratory Species of Wild Animals (CMS), International Council for the Exploration of the Seas (ICES),International Whaling Commission (IWC), North Atlantic
Marine Mammal Commission (NAMMCO), and NGOs,
including Marine Stewardship Council (MSC), Whale andDolphin Conservation (WDC), and the World Wildlife
Fund (WWF). Kato, Advisor of ICR, participated in themeeting as an expert.
The report of the meeting can be found in the website
of FAO (http://www.fao.org/home/en/).

Concarneau Marine Station, Concarneau, France.

FAO headquarters, Rome, Italy.

FAO Expert Meeting to Develop Technical Guidelines to Reduce Bycatch of Marine Mammals

Annual meeting of the North Paciﬁc Marine
Science Organization (PICES)The Food and Agriculture Organization of the United Nations (FAO) is a specialized agency of the United Nations
that leads international eﬀorts to defeat hunger. The FAO
was formed on 16 October 1945 and has its headquarters
in Rome, Italy. As of August 2018, the FAO has 197 member states. The agency is directed by the Conference ofMember Nations, which meets every two years. The Conference elects a council of 49 member states that acts as
an interim governing body, and the Director-General, thatheads the agency. FAO is composed of six departments:

The North Paciﬁc Marine Science Organization (PICES) isan intergovernmental science organization establishedin 1992 to promote and coordinate marine scientiﬁc research in the North Paciﬁc Ocean and its adjacent seas,
and to provide a mechanism for information and dataexchange among scientists in its member countries. Itspresent members are Canada, Japan, Peopleʼs Republic ofChina, Republic of Korea, the Russian Federation, and theUnited States of America.
The 2019 meeting of the PICES was held at the Victoria,

60

Participation of scientists of the Institute of Cetacean Research in International Meetings in 2019

BC, Canada from 16 to 27 October. One scientist from ICR
participated in the meeting (Tamura). He presented thestudy ʻEstimation of prey consumption by marine mammals in the PICES regions -Update of Hunt et al. (2000)-ʼ
as an oral presentation at the session ʻImplications of Prey
Consumption by Marine Birds, Mammals, and Fish in the
North Paciﬁc.ʼ Konishi, Matsuoka and Hakamada wereco-author in this study. Tamura, Hakamada and Matsuoka
were co-authors of another study ʻSpatial estimation of
prey consumption by sei, Brydeʼs and common minke
whales in the western North Paciﬁc during the summersof 2008–2009: Density surface model approach,ʼ that wasalso presented at the same session.
The report of the meeting can be found in the website
of PICES (https://meetings.pices.int/).

and stock structure of large whales in the Indo-Paciﬁcregion of the Antarctic (JASS-A).
The report of the meeting can be found in the websiteof NAMMCO (https://nammco.no/).

Tórshavn Marina, Faroe Islands.

19th World Marine Mammal Conference
Victoria Conference Centre, Victoria, Canada.

Annual meeting of the North Atlantic Marine Mammal Commission (NAMMCO) Scientiﬁc
Committee (SC)The North Atlantic Marine Mammal Commission(NAMMCO) is an international body for cooperation on
the conservation, management and study of marine
mammals in the North Atlantic. The NAMMCO Agreement was signed in Nuuk, Greenland on 9 April 1992 by
Norway, Iceland, Greenland and the Faroe Islands, andentered into force on 8 July 1992. The agreement focuseson modern approaches to the study of the marine ecosystem as a whole, and to better understanding the roleof marine mammals in the ecosystem. NAMMCO has a
Scientiﬁc Committee (SC) which meets annually.
The 2019 NAMMCO SC meeting was held at Tórshavn
Marina, Faroe Islands from 29 October to 1 November.
Three scientists from ICR participated in the meeting(Pastene, Isoda and Taguchi) as observers from Japan.
They presented the 2017–2019 Japan progress reporton cetacean research as well an outline of the research
program to investigate the abundance, abundance trends

The World Marine Mammal Conference (WMMC) is a
joint conference between the Society for Marine Mammalogy (SMM) and the European Cetacean Society (ECS).
The ECS was founded in January 1987 with the aim topromote and advance the scientiﬁc studies and conservation eﬀorts of marine mammals and disseminate
information about them to the society and the public.
The ECS convenes once a year in a European country,
alternating between southern and northern Europe asmuch as possible, with invited international authorities.
The SMM was founded in 1981 and is the largest international association of marine mammal scientists in theworld. The mission of the SMM is to promote the global
advancement of marine mammal science and contributeto its relevance and impact in education, conservationand management.
The 19th WMMC was held at the Centre de Convencions Internacional de Barcelona (CCIB), Barcelona, Catalonia, Spain from 7–12 December 2019. Two scientists
from the ICR participated in the conference (Konishi and
Takahashi) presenting the studies ʻChanges in sei whale
feeding habits in response to ﬁsh species replacement in
the western North Paciﬁc during 2002–2018,ʼ and ʻA com61

Technical Reports of the Institute of Cetacean Research (2019)

parison of the diet composition derived from skin stable
isotopes and stomach contents for two baleen whale species: sei and Brydeʼs whales in the western North Paciﬁcʼ
as posters at the session ʻForaging Ecology.ʼ
Konishi, Tamura and Bando were co-authors of thestudy ʻTracing life history of immature Antarctic minke
whales: stable isotope oscillation in baleen revealed ontogenetic diet shifts and seasonal migration,ʼ presented
as a poster at the session ʻForaging Ecology.ʼ Matsuoka
was co-author of the studies ʻEstimation of population dynamics for the Antarctic blue whale using Bayesian statespace modelsʼ and ʻEstimation of relationship between
density surface of humpback whales and environmental
factors in the North Paciﬁc ocean using IWC-POWER
data,ʼ presented as posters at the session ʻPopulation
Biology and Abundanceʼ and ʻHabitat and Distribution.ʼ
Katsumata and Kato submitted the study ʻExpansion of
wintering ground of the humpback whales in the North
Paciﬁc: Beginning of the seasonal migration to around
Hachijo Island, Izu Archipelago,ʼ which was presented asa poster at the session ʻHabitat and Distribution.ʼ

ʻEcopath 35 Years—Making Ecosystem-BasedManagement Operationalʼ ConferenceThis conference and associated workshops was held at
the Fish and Wildlife Research Institute, St. Petersburg,
Florida, USA from 4 to 11 December 2019, to showcase
35 years of progress using the Ecopath approach in ﬁelds
such as ﬁsheries management, marine conservation, ecosystem dynamics, climate impacts, and ecosystem-based
management, as well as to introduce new aspects of theapproach.
Tamura and Hakamada were the co-authors of a contributing study presented to the conference titled ʻEcosystem modeling in the western North Paciﬁc from 1994
to 2013 using Ecopath with Ecosim (EwE) with focus onforage ﬁsh and baleen whales.ʼ

The Fish and Wildlife Research Institute, St. Petersburg, Florida,USA.

The Centre de Convencions Internacional de Barcelona (CCIB),
Barcelona, Spain.

62

Technical Reports of the Institute of Cetacean Research (2019)

pp. 63–64

National meetings

Participation of scientists of the Institute of Cetacean Research in
National Meetings in 2019
Annual meeting of the Ecological Society ofJapan (ESJ)The Ecological Society of Japan was founded in 1953 topromote research in all aspects of ecology. The main
events organized by the society are the annual meetings held in spring in one of the main cities of Japan. The
ESJ currently has an enrollment of over 3,900 members
including students and non-professionals. The ESJ works
not only on science matters but it also puts eﬀort into
dissemination of information among the general public.
The 2019 meeting of the ESJ was held at the Kobe
Convention Center, Hyogo from 15 to 19 March. Konishi,
a scientist from the Institute of Cetacean Research (ICR)
participated in the meeting making an oral presentation of the study ʻRelationship between the Antarctic
minke whale and sea ice at Southern Ocean by satellite
monitored trackingʼ at the session on Behavior (Isoda andBando from the ICR were co-authors in this study).

ent their research activities, exchange information, andcreate partnerships in vital areas of research.
The 2019 spring meeting of the JSFS was held at theTokyo University of Marine Science and Technology,
Tokyo from 26 to 29 March. Three scientists from theICR (Bando, Tamura and Konishi) were co-authors in the
study ʻEstimation of feeding habits of the pregnant Antarctic minke whales from stable isotope ratios in baleen
plates,ʼ which was presented as a poster.

Tokyo University of Marine Science and Technology, Tokyo.

Annual Meeting of the Mammal Society of Japan(MSJ)

Kobe Convention Center, Hyogo.

Annual meeting of the Japanese Society ofFisheries Science (JSFS)
The Japanese Society of Fisheries Science (JSFS) was established in 1932. It is a non-proﬁt registered society dedicated to the promotion of all aspects of ﬁsheries science.
The society fulﬁlls its global commitment by promoting
science, striving to achieve sustainable development
while recognizing the crucial need of preserving the natural aquatic resources. It also strives to forge relationships
with the industry comprising both capture and cultureﬁsheries, the ﬁshing environment, and the concerned
trade. The main events organized by the society are thebiannual meetings held in spring and autumn in one of
the main cities of Japan. In this forum the members pres-

The Mammal Society of Japan (MSJ) was established in
1987 by uniting two academic organizations, the Mammalogical Society of Japan and the Research Group of
Mammalogists, which were founded in 1949 and 1955,
respectively. The MSJ currently has an enrollment of over
1,100 members including students and non-professionals.
The annual meeting of the society consists of academic
sessions (symposia, oral presentations, and poster papers), workshops, and a business meeting.
The 2019 autumn meeting of MSJ was held at Chuo
University, Tokyo, from 15 to 18 September. Several scientists from the ICR were co-authors in studies presented
to the meeting: ʻGrowth dependent changes of external morphology of fetus of the Antarctic minke whaleʼ
(Bando, Fujise and Kato) (poster presentation); ʻGut microbiome of baleen whale in the Antarctic and western
North Paciﬁcʼ (Tamura) (oral presentation at the session
Conservation and Management); ʻEstimation of population dynamics for the Antarctic blue whale using Bayesianstate-space modelsʼ (Matsuoka) (oral presentation at the63Technical Reports of the Institute of Cetacean Research (2019)

Chuo University, Tokyo.

session Conservation and Management); and ʻRelationship between density distribution of humpback whales
and environmental factors in the North Paciﬁc Ocean
using IWC-POWER dataʼ (Matsuoka) (oral presentation at
the session Conservation and Management).

64Technical Reports of the Institute of Cetacean Research (2019)

pp. 65–82

Peer-reviewed publications

List of peer-reviewed publications based on the Institute of
Cetacean Research (ICR)ʼs surveys up to 2019
This section presents a list of peer-reviewed publications
based on data collected by surveys conducted under
special scientiﬁc permit (JARPA/JARPAII/NEWREP-A and
JARPN/JARPNII/NEWREP-NP), including both lethal andnon-lethal techniques. Peer-reviewed publications basedon these surveys are focused mainly on topics related toassessment and management of large whales. However
samples and data collected by the surveys have also been
useful to carry out studies of a more academic-oriented
nature. Publications based on such studies are also listed
here.
This section also includes a list of peer-reviewed publications resulting from other surveys and research activities, diﬀerent from special scientiﬁc permit surveys.
Publications having as a ﬁrst author a non-ICR scientist commonly followed a data request or collaboration
research agreement with ICR. In a few cases, externalscientists used published data from ICR surveys in theiranalyses and publications, without a formal agreementwith ICR. These cases are indicated by an asterisk (*).

JARPA/JARPAII/NEWREP-A surveys
1989 (2)Kato, H., Hiroyama, H., Fujise, Y. and Ono, K. 1989.
Preliminary report of the 1987/88 Japanese feasibility study of the special permit proposal for Southern
Hemisphere minke whales. Rep. int. Whal. Commn 39:
235–248.
Nakamura, T., Ohnishi, S. and Matsumiya, Y. 1989. A
Bayesian cohort model for catch-at-age data obtained
from research takes of whales. Rep. int. Whal. Commn
39: 375–382.
1990 (8)Butterworth, D.S. and Punt, A.E. 1990. Some preliminary
examinations of the potential information content
of age-structure data from Antarctic minke whale research catches. Rep. int. Whal. Commn 40: 301–315.
Ichii, T. 1990. Distribution of Antarctic krill concentrations
exploited by Japanese krill trawlers and minke whales.
Proc. NIPR Symp. Polar Biol. 3: 36–56.
Itoh, S., Takenaga, F. and Tsuyuki, H. 1990. Studies on lipidsof the Antarctic minke whale. I. The fatty acid compositions of the minke whale blubber oils caught on 1987/88

season. Yukagaku 39 (7): 486–490 (in Japanese).
Kasamatsu, F., Kishino, H. and Hiroyama, H. 1990. Estimation of the number of minke whale (Balaenoptera
acutorostrata) schools and individuals based on the
1987/88 Japanese feasibility study data. Rep. int. Whal.
Commn 40: 239–247.
Kato, H., Fujise, Y., Yoshida, H., Nakagawa, S., Ishida, M.
and Tanifuji, S. 1990. Cruise report and preliminary
analysis of the 1988/89 Japanese feasibility study ofthe special permit proposal for southern hemisphereminke whales. Rep. int. Whal. Commn 40: 289–300.
Kato, H., Kishino, H. and Fujise, Y. 1990. Some analyses on
age composition and segregation of southern minke
whales using samples obtained by the Japanese feasibility study in 1987/88. Rep. int. Whal. Commn 40:
249–256.
Nagasaki, F. 1990. The Case for Scientiﬁc Whaling. Nature
334: 189–190.
Tanaka, S. 1990. Estimation of natural mortality coeﬃcient of whales from the estimates of abundance andage composition data obtained from research catches.
Rep. int. Whal. Commn 40: 531–536.
1991 (9)Bergh, M.O., Butterworth, D.S. and Punt, A.E. 1991. Further examination of the potential information content
of age-structure data from Antarctic minke whale
research catches. Rep. int. Whal. Commn 41: 349–361.
Ichii, T. and Kato, H. 1991. Food and daily food consumption of southern minke whales in the Antarctic. Polar
Biol 11 (7): 479–487.
Kasamatsu, F., Kishino, H. and Taga, Y. 1991. Estimationof southern minke whale abundance and school size
composition based on the 1988/89 Japanese feasibility
study data. Rep. int. Whal. Commn 41: 293–301.
Kato, H., Fujise, Y. and Kishino, H. 1991. Age structure andsegregation of southern minke whales by the data obtained during Japanese research take in 1988/89. Rep.
int. Whal. Commn 41: 287–292.
Kato, H. and Miyashita, T. 1991. Migration strategy ofsouthern minke whales in relation to reproductive
cycles estimated from foetal lengths. Rep. int. Whal.
Commn 41: 363–369.
Kato, H., Zenitani, R. and Nakamura, T. 1991. Inter-reader
calibration in age readings of earplugs from southern
65Technical Reports of the Institute of Cetacean Research (2019)minke whale, with some notes of age readability. Rep.
int. Whal. Commn 41: 339–343.
Kishino, H., Kato, H., Kasamatsu, F. and Fujise, Y. 1991.
Detection of heterogeneity and estimation of population characteristics from the ﬁeld survey data: 1987/88
Japanese feasibility study of the Southern Hemisphereminke whales. Ann. Inst. Statist. Math. 43 (3): 435–453.
Nakamura, T. 1991. A new look at a Bayesian cohortmodel for time-series data obtained from researchtakes of whales. Rep. int. Whal. Commn 41: 345–348.
Wada, S., Kobayashi, T. and Numachi, K. 1991. Genetic
variability and diﬀerentiation of mitochondrial DNA in
minke whales. Rep. int. Whal. Commn (special issue)
13: 203–215.
1992 (2)Nakamura, T. 1992. Simulation trials of a Bayesian cohortmodel for time-series data obtained from researchtakes of whales. Rep. int. Whal. Commn 42: 421–427.
Tanaka, S., Kasamatsu, F. and Fujise, Y. 1992. Likely precision of estimates of natural mortality rates fromJapanese research data for Southern Hemisphereminke whales. Rep. int. Whal. Commn 42: 413–420.
1993 (7)Fujise, Y., Ishikawa, H., Saino, S., Nagano, M., Ishii, K.,
Kawaguchi, S., Tanifuji, S., Kawashima, S. and Miyakoshi H. 1993. Cruise report of the 1991/92 Japanese research in Area IV under the special permit for Southern
Hemisphere minke whales. Rep. int. Whal. Commn 43:
357–371.
Hasunuma, R., Ogawa, T., Fujise, Y. and Kawanishi,
Y. 1993. Analysis of selenium metabolites in urine
samples of minke whale (Balaenoptera acutorostrata)
using ion exchange chromatography. Comp. Biochem.
Physiol. 104C (1): 87–89.
Itoh, S., Takenaga, F. and Tsuyuki, H. 1993. Studies onlipids of the Antarctic minke whale. II. The fatty acidcompositions of the blubber oils of minke whale anddwarf minke whale caught on 1988/89 and 1989/90
seasons. Yukagaku 42 (12): 1007–1011 (in Japanese).
Iwata, H., Tanabe, S., Sakai, N. and Tatsukawa, R. 1993.
Distribution of persistent organochlorines in the oceanic air and surface seawater and the role of ocean on
their global transport and fate. Environ. Sci. Technol.
27: 1080–1098.
Kasamatsu, F., Yamamoto, Y., Zenitani, R., Ishikawa, H.,
Ishibashi, T., Sato, H., Takashima, K. and Tanifuji, S.
1993. Report of the 1990/91 southern minke whale
research cruise under scientiﬁc permit in Area V. Rep.
66

int. Whal. Commn 43: 505–522.
Nakamura, T. 1993. Two-stage Bayesian cohort modelfor time-series data to reduce bias in the estimate ofmean natural mortality rate. Rep. int. Whal. Commn
43: 343–348.
Pastene, L.A., Kobayashi, T., Fujise, Y. and Numachi, K.
1993. Mitochondrial DNA diﬀerentiation in Antarctic
minke whales. Rep. int. Whal. Commn 43: 349–355.
1994 (3)Kimoto, H., Endo, Y. and Fujimoto, K. 1994. Inﬂuence ofinteresteriﬁcation on the oxidative stability of marine
oil triacylglycerols. JAOCS 71 (5): 469–473.
Pastene, L.A., Fujise, Y. and Numachi, K. 1994. Diﬀerentiation of mitochondrial DNA between ordinary anddwarf forms of southern minke whale. Rep. int. Whal.
Commn 44: 277–281.
Yoshioka, M., Okumura, T., Aida, K. and Fujise, Y. 1994. A
proposed technique for quantifying muscle progesterone content in the minke whales (Balaenoptera acutorostrata). Can. J. Zoo. 72: 368–370.
1995 (3)
Fukui, Y., Mogoe, T., Terawaki, Y., Ishikawa, H., Fujise,
Y. and Ohsumi, S. 1995. Relationship between physiological status and serum constituent values in minke
whales (Balaenoptera acutorostrata). Journal of Reproduction and Development 41 (3): 203–208.
Ishikawa, H. and Amasaki, H. 1995. Development andphysiological degradation of tooth buds and development of rudiment of baleen plate in Southern minke
whale, Balaenoptera acutorostrata. J. Vet. Med. Sci. 57(4): 665–670.
Kasamatsu, F., Nishiwaki, S. and Ishikawa, H. 1995. Breeding areas and southbound migrations of southernminke whales Balaenoptera acutorostrata. Mar. Ecol.
Prog. Ser. 119: 1–10.
1996 (7)Bakke, I., Johansen, S., Bakke, O. and El-Gewely, M.R.
1996. Lack of population subdivision among the minke
whales (Balaenoptera acutorostrata) from Icelandic
and Norwegian waters based on mitochondrial DNA
sequences. Marine Biology 125: 1–9.
Butterworth, D.S. and Geromont, H.F. 1996. On the provision of advice on the eﬀect on stock(s) of scientiﬁc
permit catches, with particular reference to proposed
research catches of minke whales from Antarctic Area
IV. Rep. int. Whal. Commn 46: 653–655.
Butterworth, D.S., Punt, A.E., Geromont, H.F., Kato, H. andList of peer-reviewed publications based on the Institute of Cetacean Research (ICR)ʼs surveys up to 2019

Miyashita, T. 1996. An ADAPT approach to the analysis
of catch-at-age information for Southern Hemisphereminke whales. Rep. int. Whal. Commn 46: 349–359.
Fukui, Y., Mogoe, T., Jung, Y.G., Terawaki, Y., Miyamoto, A.,
Ishikawa, H., Fujise, Y. and Ohsumi, S. 1996. Relationships among morphological status, steroid hormones,
and post-thawing viability of frozen spermatozoa ofmale minke whales (Balaenoptera acutorostrata).
Marine Mammal Science 12 (1): 28–37.
Iga, K., Fukui, Y., Miyamoto, A., Ishikawa, H. and Ohsumi,
S. 1996. Endocrinological observations of female minke
whales (Balaenoptera acutorostrata). Marine Mammal
Science 12 (2): 296–301.
Matsuoka, K., Fujise, Y. and Pastene, L.A. 1996. A sightingof a large school of the pygmy right whale, Caperea
marginata in the southeast Indian Ocean. Marine
Mammal Science 12 (4): 594–597.
Pastene, L.A., Goto, M., Itoh, S. and Numachi, K. 1996.
Spatial and temporal patterns of mitochondrial DNA
variation in minke whale from Antarctic Areas IV and V.
Rep. int. Whal. Commn 46: 305–314.
1997 (3)Aono, S., Tanabe, S., Fujise, Y., Kato, H. and Tatsukawa,R. 1997. Persistent organochlorines in minke whale(Balaenoptera acutorostrata) and their prey species
from the Antarctic and the North Paciﬁc. Environmental Pollution 98: 81–89.
Fukui, Y., Mogoe, T., Ishikawa, H. and Ohsumi, S. 1997a.
Factors aﬀecting in vitro maturation of minke whale(Balaenoptera acutorostrata) follicular oocytes. Biology of Reproduction 56: 523–528.
Fukui, Y., Mogoe, T., Ishikawa, H. and Ohsumi, S. 1997b.
In vitro fertilization of in vitro matured minke whale(Balaenoptera acutorostrata) follicular oocytes. Marine Mammal Science 13 (3): 395–404.
1998 (7)
Ichii, T., Shinohara, N., Fujise, Y., Nishiwaki, S. and Matsuoka, K. 1998. Interannual changes in body fat conditionindex of minke whales in the Antarctic. Mar. Ecol. Prog.
Ser. 175: 1–12.
Ito, S., Takenaga, F. and Tsuyuki, H. 1998. Lipids in Antarctic minke whales III. Site and sexual diﬀerences ofmuscle lipids. J. Jpn. Oil Chem. Soc. 47 (2): 191–194 (inJapanese).
Kida, M.Y. 1998. Morphology of the tracheobronchial
tree and the route of the pulmonary artery in the fetal
minke whale (Balaenoptera acutorostrata). Okajimas
Folia Anat. Jpn.75 (5): 251–258.

Mogoe, T., Fukui, Y., Ishikawa, H. and Ohsumi, S. 1998a.
Morphological observations of frozen-thawed spermatozoa of Southern minke whales (Balaenoptera acutorostrata). Journal of Reproduction and Development 44(1): 95–100.
Mogoe, T., Fukui, Y., Ishikawa, H. and Ohsumi, S. 1998b.
Eﬀects of diluent composition and temperature on
motility and viability after liquid storage and cryopreservation of minke whale (Balaenoptera acutorostrata) spermatozoa. Marine Mammal Science 14(4): 854–860.
Nagasawa, K., Yamada, T.K. and Ishikawa, H. 1998. Measurements of the skeleton of a minke whale (Balaenoptera acutorostrata) from the Antarctic Ocean. Bulletinof the Yamagata Prefectural Museum 20: 1–19.
Terabayashi, T. and Kawanishi, Y. 1998. Naturally occurring ganglioside lactones in minke whale brain. Carbohydrate Research 307 (3): 281–290.
1999 (4)Bannister, J.L., Pastene, L.A. and Burnell, S.R. 1999.
First record of movement of a southern right whale(Eubalaena australis) between warm water breeding
grounds and the Antarctic Ocean, South of 60°S. Marine Mammal Science 15 (4): 1337–1342.
Butterworth, D.S., Punt, A.E. Geromont, H.F., Kato, H. andFujise, Y. 1999. Inferences on the dynamics of Southern
Hemisphere minke whales from ADAPT analyses ofcatch-at-age information. J. Cetacean Res. Manage. 1(1): 11–32.
Ishikawa, H., Amasaki, H., Dohguchi, H., Furuya, A. andSuzuki, K. 1999. Immunohistological distributions ofﬁbronectin, tenascin, type I, III and IV collagens, andlaminin during tooth development and degeneration infetuses of minke whale, Balaenoptera acutorostrata. J.
Vet. Med. Sci. 61 (3): 227–232.
Thomson, R.B., Butterworth, D.S. and Kato, H. 1999. Has
the age at transition of southern hemisphere minke
whales declined over recent decades? Marine Mammal Science 15 (3): 661–682.
2000 (5)Asada, M., Horii, M., Mogoe, T., Fukui, Y., Ishikawa, H.
and Ohsumi, S. 2000. In vitro maturation and ultrastructural observation of cryopreserved minke whale(Balaenoptera acutorostrata) follicular oocytes. Biology of Reproduction 62 (2): 253–259.
Kasamatsu, F., Matsuoka, K. and Hakamada, T. 2000. Interspeciﬁc relationships in density among the whale
community in the Antarctic. Polar Biol 23 (7): 466–473.
67

Technical Reports of the Institute of Cetacean Research (2019)

Mogoe, T., Suzuki, T., Asada, M., Fukui, Y., Ishikawa, H. andOhsumi, S. 2000. Functional reduction of the Southernminke whale (Balaenoptera acutorostrata) testis during the feeding season. Marine Mammal Science 16(3): 559–569.
Rosenbaum, H.C., Brownell, R.L., Brown, M.W., Schaeﬀ, C.,
Portway, V., White, B.N., Malik, S., Pastene, L.A., Pateneude, N.J., Baker, C.S., Goto, M., Best, P.B., Clapham,
P.J., Hamilton, P., Moore, M., Payne, R., Rowntree, V.,
Tynan, C.T., Bannister, J.L. and DeSalle, R. 2000. Worldwide genetic diﬀerentiation of Eubalaena: questioning
the number of right whale species. Molecular Ecology
9: 1793–1802.
Wei, H. and Fukui, Y. 2000. Fertilizability of ovine, bovine
or minke whale (Balaenoptera acutorostrata) spermatozoa intracytoplasmically injected into bovine oocytes. Zygote 8 (3): 267–274.
2001 (3)Asada, M., Tetsuka, M., Ishikawa, H., Ohsumi, S. andFukui, Y. 2001. Improvement on in vitro maturation,
fertilization and development of minke whale (Balaenoptera acutorostrata) oocytes. Theriogenology 56 (4):521–533.
Asada, M., Wei, H., Nagayama, R., Tetsuka, M., Ishikawa,
H., Ohsumi, S. and Fukui, Y. 2001. An attempt at intracytoplasmic sperm injection of frozen-thawed minke
whale (Balaenoptera bonaerensis) oocytes. Zygote 9(3): 299–307.
Suzuki, T., Mogoe, T., Asada, M., Miyamoto, A., Tetsuka,
M., Ishikawa, H., Ohsumi, S. and Fukui, Y. 2001. Plasmaand pituitary concentrations of gonadotropins (FSHand LH) in minke whales (Balaenoptera acutorostrata)
during the feeding season. Theriogenology 55 (5):1127–1141.
2002 (6)Abe, H. and Goto, M. 2002. The application of microsatellite DNA for determining population structure of minke
whale. pp. 109–113. In: Nishimura, A. (Ed). Technical
Reports of the Hokkaido National Fisheries ResearchInstitute No.5. Hokkaido National Fisheries ResearchInstitute, Hokkaido.
Kunito, T., Watanabe, I., Yasunaga, G., Fujise, Y. and Tanabe, S. 2002. Using trace elements in skin to discriminate the populations of minke whale in southern hemisphere. Marine Environmental Research 53: 175–197.
Murase, H., Matsuoka, K., Ichii, T. and Nishiwaki, S. 2002.
Relationship between the distribution of euphausiids
and baleen whales in the Antarctic (35°E–145°W).
68

Polar Biol 25 (2): 135–145.
Pastene, L.A., Goto, M. and Kanda, N. 2002. The utility of
DNA analysis for the management and conservation oflarge whales. Fish Sci 68 (Suppl. I): 286–289.
Suzuki, M., Ishikawa, H., Otani, S., Tobayama, T., Katsumata, E., Ueda, K., Uchida, S., Yoshioka, M. and Aida,
K. 2002. The characteristics of adrenal glands and its
hormones in cetacean. Fish Sci 68 (Suppl. I): 272–275.
Urashima, T., Sato, H., Munakata, J., Nakamura, T., Arai, I.,
Saito, T., Tetsuka, M., Fukui, Y., Ishikawa, H., Lyndersen,
C. and Kovacs, K.M. 2002. Chemical characterization of
the oligosaccharides in beluga (Delphinapterus leucas)
and minke whale (Balaenoptera acutorostrata) milk.
Comparative Biochemistry and Physiology Part B 132:
611–624.
2003 (5)Hayashi, K., Nishida, S., Yoshida, H., Goto, M., Pastene,
L.A. and Koike, H. 2003. Sequence variation of the DQB
allele in the cetacean MHC. Mammal Study 28 (2):89–96.
Matsuoka, K., Watanabe, T., Ichii, T., Shimada, H. andNishiwaki, S. 2003. Large whale distributions (south of
60°S, 35°E–130°E) in relation to the Southern Boundary of the Antarctic Circumpolar Current. pp. 26–30.
In: Antarctic Biology in a Global Context. Proceedingsof the VIIIth SCAR International Biology Symposium, 27
August-1 September 2001. Vriji Universiteit, Amsterdam, The Netherlands, Backhuys Publisheres, Leiden.
Nishida, S., Hayashi, K., Pastene, L.A., Goto, M., Kanda, N.
and Koike, H. 2003. Polymorphic analysis of cetacean
MHC - A case study on the minke whales -. Mammalian
Science (Suppl.) 3: 75–78 (in Japanese).
Nishida, S., Pastene, L.A., Goto, M. and Kanda, N. 2003.
SRY gene structure and phylogeny in the cetacean species. Mammal Study 28 (1): 57–66.
Ohishi, K., Zenitani, R., Bando, T., Goto, Y., Uchida, K.,
Maruyama, T., Yamamoto, S., Miyazaki, N. and Fujise, Y.
2003. Pathological and serological evidence of Brucella-infection in baleen whales (Mysticeti) in the western
North Paciﬁc. Comp. Immun. Microbiol. Infect. Dis. 26(2): 125–136.
2004 (8)Amemiya, K., Iwanami, Y., Kobayashi, T., Terao, T., Fukui,Y., Ishikawa, H., Ohsumi, S., Hirabayashi, M. and Hochi,
S. 2004. Acquirement of oocyte-activating factor in
Antarctic minke whale (Balaenoptera bonaerensis)
spermatogenic cells, assessed by meiosis resumptionof microinseminated mouse oocytes. J. Mamm. Ova

List of peer-reviewed publications based on the Institute of Cetacean Research (ICR)ʼs surveys up to 2019

Res. 21: 149–156.
Branch, T.A., Matsuoka, K. and Miyashita, T. 2004. Evidence for increase in Antarctic blue whales based on
Bayesian modeling. Marine Mammal Science 20 (4):726–754.
Fujihira, T., Kinoshita, M., Sasaki, M., Ohnishi, M., Ishikawa, H., Ohsumi, S. and Fukui, Y. 2004. Comparative
studies on lipid analysis and ultrastructure in porcine
and southern minke whale (Balaenoptera bonaerensis)
oocytes. Journal of Reproduction and Development 50(5): 525–532.
Fukui, Y., Togawa, M., Abe, N., Takano, Y., Asada, M.,
Okada, A., Iida, K., Ishikawa, H. and Ohsumi, S. 2004.
Validation of the sperm quality analyzer and the hypoosmotic swelling test for frozen-thawed ram and minke
whale (Balaenoptera bonarensis) spermatozoa. Journal of Reproduction and Development 50 (1): 147–154.
Ikumi, S., Sawai, K., Takeuchi, Y., Iwayama, H., Ishikawa,
H., Ohsumi, S. and Fukui, Y. 2004. Interspecies somatic
cell nuclear transfer for in vitro production of Antarctic
minke Whale (Balaenoptera bonaerensis) Embryos.
Cloning and Stem Cells 6 (3): 284–293.
Iwayama, H., Hochi, S., Kato, M., Hirabayashi, M., Kuwayama, M., Ishikawa, H., Ohsumi, S. and Fukui, Y. 2004.
Eﬀects of cryodevice type and donorʼs sexual maturity
on vitriﬁcation of minke whale (Balaenoptera bonaerensis) oocytes at germinal vesicle-stage. Zygote 12 (4):333–338.
Muranishi, Y., Sasaki, M., Hayashi, K., Abe, N., Fujihira, T.,
Ishikawa, H., Ohsumi, S., Miyamoto, A. and Fukui, Y.
2004. Relationship between the appearance of preantral follicles in the fetal ovary of Antarctic minke whales(Balaenoptera bonaerensis) and hormone concentrations in the fetal heart, umbilical cord and maternal
blood. Zygote 12 (2): 125–132.
Tetsuka, M., Asada, M., Mogoe, T., Fukui, Y., Ishikawa, H.
and Ohsumi, S. 2004. The pattern of ovarian development in the prepubertal Antarctic minke whale (Balaenoptera bonaerensis). Journal of Reproduction andDevelopment 50 (4): 381–389.
2005 (6)Ishikawa, H. and Shigemune, H. 2005. Improvements
in more humane killing methods of Antarctic minke
whales, Balaenoptera bonaerensis, in the Japanese
Whale Research Program under Special Permit in the
Antarctic Sea (JARPA). Jpn. J. Zoo Wildl. Med. 10 (1):
27–34.
Iwayama, H., Ishikawa, H., Ohsumi, S. and Fukui, Y. 2005.
Attempt at in vitro maturation of minke whale (Balae-

noptera bonaerensis) oocytes using a portable CO2
incubator. Journal of Reproduction and Development
51 (1): 69–75.
Matsuoka, K., Pitman, R. and Marques, F. 2005. A note ona pigmy right whale (Caperea marginata) sighting inthe southwestern Paciﬁc Ocean. J. Cetacean Res. Manage. 7(1): 71–73.
Matsuoka, K., Hakamada, T., Kiwada, H., Murase, H. andNishiwaki, S. 2005. Abundance increases of large baleen whales in the Antarctic based on the sighting survey during Japanese Whale Research Program (JARPA).
Global Environmental Research 9 (2): 105–115.
Nikaido, M., Sasaki, T., Makino, H., Goto, M., Kanda, N.,
Pastene, L.A. and Okada, N. 2005. Phylogenetic reconstruction of baleen whales and detection of their pastextensive radiation event by the SINE insertion analysis. Fossils 77: 22–28 (in Japanese).
Sasaki, T., Nikaido, M., Hamilton, H., Goto, M., Kato, H.,
Kanda, N., Pastene, L.A., Cao, Y., Fordyce, R.E., Hasegawa, M. and Okada, N. 2005. Mitochondrial phylogenetics and evolution of mysticete whales. Systematic
Biology 54 (1): 77–90.
2006 (9)Fujihira, T., Kobayashi, M., Hochi, S., Hirabayashi, M.,
Ishikawa, H., Ohsumi, S. and Fukui, Y. 2006. Developmental capacity of Antarctic minke whale (Balaenoptera bonaerensis) vitriﬁed oocytes following in vitro
maturation, and parthenogenetic activation or intracytoplasmic sperm injection. Zygote 14 (2): 89–95.
Honda, K., Aoki, M. and Fujise, Y. 2006. Echochemical approach using mercury accumulation of Antarctic minke
whale, Balaenoptera bonaerensis, as tracer of historical change of Antarctic marine ecosystem during 1980–
1999. Bull. Environ. Contam. Toxicol. 76: 140–147.
Iwanami, K., Mita, H., Yamamoto, Y., Fujise, Y., Yamada,T. and Suzuki, T. 2006. cDNA-derived amino acid sequences of myoglobins from nine species of whales
and dolphins. Comparative Biochemistry and Physiology, Part B 145: 249–256.
Kobayashi, T., Amemiya, K., Takeuchi, K., Tsujioka, T.,
Tominaga, K., Hirabayashi, M., Ishikawa, H., Fukui,
Y. and Hochi, S. 2006. Contribution of spermatozoal
centrosomes to the microtubule-organizing centre in
Antarctic minke whale (Balaenoptera bonaerensis).
Zygote 14 (1): 45–51.
Konishi, K. 2006. Characteristics of blubber distribution
and body condition indicators for Antarctic minke
whale (Balaenoptera bonaerensis). Mammal Study 31(1): 15–22.
69

Technical Reports of the Institute of Cetacean Research (2019)

Mori, M. and Butterworth, D.S. 2006. A ﬁrst step towards
modelling the krill–predator dynamics of the Antarctic
ecosystem. CCAMLR Science 13: 217–277.
Nikaido, M., Hamilton, H., Makino, H., Sasaki, T., Takahashi, K., Goto, M., Kanda, N., Pastene, L.A. and Okada,N. 2006. Baleen whale phylogeny and a past extensive
radiation event revealed by SINE insertion analysis.
Mol. Biol. Evol. 23 (5): 866–873.
Rock, J., Pastene, L.A., Kaufman, G., Forestell, P., Matsuoka, K. and Allen, J. 2006. A note on East Australia
Group V Stock humpback whale movement between
feeding and breeding areas based on photo-identiﬁcation. J. Cetacean Res. Manage. 8 (3): 301–305.
Yabuki, T., Suga, T., Hanawa, K., Matsuoka, K., Kiwada, H.
and Watanabe, T. 2006. Possible source of the Antarctic bottom water in the Prydz Bay Region. Journal of
Oceanography 62 (5): 649–655.
2007 (7)Asada, M., Tetsuka, M., Ishikawa, H., Ohsumi, S. andFukui, Y. 2007. Ultrastructural changes during maturation and cryopreservation of follicular oocytes of Antarctic minke whales (Balaenoptera bonaerensis). Jpn. J.
Zoo. Wildl. Med. 12 (1): 51–66.
Branch, T.A., Staﬀord, K.M., Palacios, D.M., Allison, C.,
Bannister, J.L., Burton, C.L.K., Cabrera, E., Carlson, C.A.,
Galletti Vernazzani, B., Gill, P.C., Hucke-Gaete, R., Jenner, K.C.S., Jenner, Mn. M., Matsuoka, K., Mikhalev,
Y.A., Miyashita, T., Morrice, M.G., Nishiwaki, S., Sturrock, V.J., Tormosov, D., Anderson, R.C., Baker, A.N.,
Best, P.B., Borsa, P., Brownell Jr, R.L., Childerhouse,
S., Findlay, K.P., Gerrodette, T., Ilangakoon, A.D., Joergensen, M., Kahn, B., Ljungblad, D.K., Maughan, B.,
Mccauley, R.D., Mckay, S., Norris, T.F., Oman Whaleand Dolphin Research Group, Rankin, S., Samaran, F.,
Thiele, D., Van Waerebeek, K. and Warneke, R.M. 2007.
Past and present distribution, densities and movements of blue whales in the Southern Hemisphere andadjacent waters. Mammal Rev. 37 (2): 116–175.
LeDuc, R.G., Dizon, A.E., Goto, M., Pastene, L.A., Kato,
H., Nishiwaki, S. and Brownell, R.L. 2007. Patterns ofgenetic variation in southern hemisphere blue whales,
and the use of assignment test to detect mixing on
the feeding grounds. J. Cetacean Res. Manage. 9 (1):73–80.
Nagai, H., Mogoe, T., Ishikawa, H., Hochi, S., Ohsumi, S.
and Fukui, Y. 2007. Follicle size-dependent changes
in follicular ﬂuid components and oocyte diameter in
Antarctic minke whales (Balaenoptera bonaerensis).
Journal of Reproduction and Development 53 (6):701265–1272.
Nishida, S., Goto, M., Pastene, L.A., Kanda, N. and Koike,
H. 2007. Phylogenetic relationships among cetaceansrevealed by Y-chromosome sequences．Zoological Science 24 (7): 723–732．
Onbe, K. Nishida, S., Sone, E., Kanda, N., Goto, M., Pastene, L.A., Tanabe, S. and Koike, H. 2007. Sequence variation in the Tbx4 gene in marine mammals．Zoological
Science 24 (5): 449–464.
Pastene, L.A., Goto, M., Kanda, N., Zerbini, A.N., Kerem,D., Watanabe, K., Bessho, Y., Hasegawa, M., Nielsen,
R., Larsen, F. and Palsbøll, P.J. 2007. Radiation andspeciation of pelagic organisms during periods ofglobal warming: the case of the common minke whale,
Balaenoptera acutorostrata. Molecular Ecology 16:1481–1495.
2008 (4)Ishikawa, H. and Shigemune, H. 2008. Comparative experiment of whaling grenades in the Japanese Whale
Research Program under Special Permit (JARPA and
JARPN). Jpn. J. Zoo Wildl. Med. 13 (1): 21–28.
Konishi, K., Tamura, T., Zenitani, R., Bando, T., Kato, H. andWalløe, L. 2008. Decline in energy storage in the Antarctic minke whale (Balaenoptera bonaerensis) in theSouthern Ocean. Polar Biol 31 (2): 1509–1520.
Ohishi, K., Fujise, Y. and Maruyama, T. 2008. Brucella spp.
in the western North Paciﬁc and Antarctic cetaceans: areview. J. Cetacean Res. Manage. 10 (1):67–72.
Yunoki, K., Ishikawa, H., Fukui, Y. and Ohnishi, M. 2008.
Chemical properties of epidermal lipids, especiallysphingolipids, of the Antarctic minke whale. Lipids 43(2): 151–159.
2009 (2)Ono, N., Yamaguchi, T., Ishikawa, H., Arakawa, M.,
Takahashi, N. Saikawa, T. and Shimada, T. 2009. Morphological varieties of the Purkinje ﬁber network inmammalian hearts, as revealed by light and electron
microscopy. Arch Histol Cytol 72 (3): 139–149.
Tamura, T. and Konishi, K. 2009. Feeding habits and prey
consumption of Antarctic minke whale (Balaenoptera
bonaerensis) in the Southern Ocean. J. Northw. Atl.
Fish. Sci. 42: 13–25.
2010 (15)
Fujise, Y., Nishiwaki, S. and Ishikawa, S. 2010. Overview of
the Japanese Whale Research Program under Special
Permit in the Antarctic (JARPA). Bull. Jpn. Soc. Fish.
Oceanogr. 74: 43–44 (in Japanese).

List of peer-reviewed publications based on the Institute of Cetacean Research (ICR)ʼs surveys up to 2019

Fujise, Y., Hatanaka, H. and Ohsumi, S. 2010. Changes
in the Antarctic marine ecosystem as revealed by the
JARPA research: What has happened to the Antarctic
minke whale stocks? Ottar (Tromsø Museum) 280:
29–34 (in Norwegian).
Glover, K.A., Kanda, N., Haug, T., Pastene, L.A., Øien, N.,
Goto, M., Seliussen, B.B. and Skaug, H.J. Migration of
Antarctic minke whales to the Arctic. PLoS ONE 5 (12):e15197.
Ishikawa, H. 2010. Animal Welfare - Introduction -. Jpn. J.
Zoo. Wildl. Med. 15 (1): 1–3 (in Japanese).
Ishikawa, H. 2010. Lethal Research for Wildlife. Jpn. J.
Zoo. Wildl. Med. 15 (1): 9–14 (in Japanese).
Kokubun, N., Yasuma, H., Murase, H. and Naganobu, M.
2010. Distribution of seabirds in the Ross Sea, Antarctica. Bull. Jpn. Soc. Fish. Oceanogr. 74: 42–43 (inJapanese).
Matsuoka, K., Kiwada, K., Murase, H. and Nishiwaki, S.
2010. Whale species composition and their distribution patterns in the Ross Sea, Antarctica. Bull. Jpn. Soc.
Fish. Oceanogr. 74: 44–45 (in Japanese).
Murase, H., Matsuoka, K., Hakamada, T., Nishiwaki, S.,
Naganobu, M. and Kitakado, T. 2010. Estimation of
spatial distribution pattern of cetacean using environmental covariates in the Ross Sea, Antarctica. Bull. Jpn.
Soc. Fish. Oceanogr. 74: 47–48 (in Japanese).
Naganobu, M. and Murase, H. 2010. Ecological linkage
between oceanographic environment and distributionof top predators and their preys in the Ross Sea region.
Bull. Jpn. Soc. Fish. Oceanogr. 74: 48–49 (in Japanese).
Naganobu, M., Murase, H., Nishiwaki, S., Yasuma, H.,
Matsukura, R., Takao, Y., Taki, K., Hayashi, T., Watanabe,Y., Yabuki, T., Yoda, Y., Noiri, Y., Kuga, M., Yoshikawa, K.,
Kokubun, N., Iwami, T., K., Itoh, K., Goto, M., Isoda, T.,
Matsuoka, K., Tamura, T. and Fujise, Y. 2010. Structureof marine ecosystem of the Ross Sea, Antarctica—overview and synthesis of the results of the Japanese multidisciplinary study by Kaiyo-Maru and JARPA—. Bull.
Jpn. Soc. Fish. Oceanogr. 74: 1–12.
Naganobu, M., Nishiwaki, S., Nagai, N. and Tohyama, D.
2010. Multidisciplinary ecological survey by the R/V
Kaiyo Maru and JARPA in the Ross Sea, Antarctica. Bull.
Jpn. Soc. Fish. Oceanogr. 74: 34–35 (in Japanese).
Pastene, L. A., Acevedo, J., Goto, M., Zerbini, A.N., Acuna,
P. and Aguayo-Lobo, A. 2010. Population structure andpossible migratory links of common minke whales,
Balaenoptera acutorostrata, in the Southern Hemisphere. Conserv Genet 11 (4): 1553–1558．
Tamura, T., Konishi, K., Nishiwaki, S., Taki, K., Hayashi, T.
and Naganobu, M. 2010. Feeding ecology of the Ant-arctic minke whales in the Ross Sea, Antarctica. Bull.
Jpn. Soc. Fish. Oceanogr. 74: 46–47 (in Japanese).
Yabuki, T., Noiri,Y., Murase, H., Kiwada, H., Matsuoka, K.
and Naganobu, M. 2010. Physical and chemical studyof hydrographic feature based on the R/V Kaiyo Maru
cruise and JARPA in the Ross Sea, Antarctica. Bull. Jpn.
Soc. Fish. Oceanogr. 74: 35–36 (in Japanese).
Zenitani, R. and Kato, H. 2010. The growth of baleen
plates in Antarctic minke whales, with special reference to the V-shape notch appearing at the outer edgeof the plates. Nippon Suisan Gakkaishi 76 (5): 870–876(in Japanese with English abstract).
2011 (1)Matsuoka, K., Hakamada, T., Kiwada, H., Murase, H. andNishiwaki, S. 2011. Abundance estimates and trends
for humpback whales (Megaptera novaeangliae) in
Antarctic Areas IV and V based on JARPA sighting data.
J. Cetacean Res. Manage. (special issue) 3: 75–94.
2012 (1)*Sremba, A.L., Hancock-Hanser, B., Branch, T.A., LeDuc,
R.L. and Baker, C.S. 2012. Circumpolar diversity andgeographic diﬀerentiation of mtDNA in the criticallyendangered Antarctic blue whale (Balaenoptera musculus intermedia). PLoS ONE 7 (3): e32579.
2013 (6)Glover, K.A., Kanda, N., Haug, T., Pastene, L.A., Øien, N.,
Seliussen, B.B., Sørvik, A.G.E. and Skaug, H.J. 2013.
Hybrids between common and Antarctic minke whales
are fertile and can back-cross. BMC Genetics 14: 25.
Hakamada, T., Matsuoka, K., Nishiwaki, S. and Kitakado,
T. 2013. Abundance estimates and trends for Antarctic
minke whales (Balaenoptera bonaerensis) in Antarctic
Areas IV and V for the period 1989/90–2004/05. J. Cetacean Res. Manage. 13 (2): 123–151.
Kitakado, T., Lockyer, C. and Punt, A.E. 2013. A statisticalmodel for quantifying age-reading errors and its application to the Antarctic minke whales. J. Cetacean Res.
Manage. 13 (3): 181–190.
Murase, H., Kitakado, T., Hakamada, T., Matsuoka, K.,
Nishiwaki, S. and Naganobu, M. 2013. Spatial distribution of Antarctic minke whales (Balaenoptera bonaerensis) in relation to spatial distributions of krill in theRoss Sea, Antarctica. Fish. Oceanogr. 22 (3): 154–173.
Sasaki, M., Amano, Y., Hayakawa, D., Tsubota, T., Ishikawa,
H., Mogoe, T., Ohsumi, S., Tetsuka, M., Miyamoto, A.,
Fukui, Y., Budipitojo, T. and Kitamura, N. 2013. Structure and steroidogenesis of the placenta in the Antarc71

Technical Reports of the Institute of Cetacean Research (2019)tic minke whale (Balaenoptera bonaerensis). Journal of
Reproduction and Development 59 (2): 159–167.
Shibata, Y., Matsuishi, T., Murase, H., Matsuoka, K.,
Hakamada, T., Kitakado, T. and Matsuda, H. 2013. Effects of stratiﬁcation and misspeciﬁcation of covariates
on species distribution models for abundance estimation from virtual line transect survey data. Fish Sci 79(4): 559–568.
2014 (3)Konishi, K., Hakamada, T., Kiwada, H., Kitakado, T. andWalløe, L. 2014. Decrease in stomach contents in the
Antarctic minke whale (Balaenoptera bonaerensis) in
the Southern Ocean. Polar Biol 37 (2): 205–215.
Punt, A.E. 2014. A summary history of the applicationof statistical catch-at-age analysis (SCAA) to Antarctic
minke whales. J. Cetacean Res. Manage. 14: 81–92.
Punt, A.E., Hakamada, T., Bando, T. and Kitakado, T. 2014.
Assessment of Antarctic minke whales using statisticalcatch-at-age analysis (SCAA). J. Cetacean Res. Manage.
14: 93–116.
2015 (2)Konishi, K. and Walløe, L. 2015. Substantial decline inenergy storage and stomach fullness in Antarctic minke
whales (Balaenoptera bonaerensis) during the 1990ʼs.
J. Cetacean Res. Manage. 15: 77–92.
Yasunaga, G., Fujise, Y., Zenitani, R., Tanabe, S. and Kato,
H. 2015. Spatial and temporal variation of PCBs and organochlorine pesticides in the Antarctic minke whales,
Balaenoptera bonaerensis, in the period 1987–2005.
Chemosphere 126: 11–17.
2016 (2)Pastene, L.A. and Goto, M. 2016. Genetic characterization and population genetic structure of the Antarctic
minke whale Balaenoptera bonaerensis in the IndoPaciﬁc region of the Southern Ocean. Fish Sci 82 (6):873–886.
Wada, N., Yamanaka, S., Shibato, J., Rakwal, R., Hirako, S.,
Iizuka, Y., Kim, H., Matsumoto, A., Kimura, A., Takenoya,F., Yasunaga, G. and Shioda, S. 2016. Behavioral andomics analyses study on potential involvement of
dipeptide balenine through supplementation in dietof senescence-accelerated mouse prone 8. Genomics
Data 10: 38–50.
2017 (3)Isoda, T. and Tamura, T. 2017. Report of a White Adélie
Penguin Pygoscelis adeliae in the Antarctic Ocean. J.
72

Yamashina Inst. Ornithol. 48 (2): 74–77.
*Leduc, R.G., Archer, F.I., Lang, A.R., Martien, K.K., Hancock-Hanser, B., Torres-Florez, J.P., Hucke-Gaete, R.,
Rosenbaum, H.C., VanWaerebeek, Bownell, R.L. andTaylor, B.L. 2017. Genetic variation in blue whales inthe eastern paciﬁc: implications for taxonomy and useof common wintering grounds. Molecular Ecology 26:
740–751.
Yasunaga, G., Pastene, L.A., Bando, T., Hakamada, T. andFujise, Y. 2017. Age estimation of Antarctic minke
whales Balaenoptera bonaerensis based on aspartic
acid racemization technique. Fish Sci 86 (6): 947–954.
2019 (2)Inoue, S., Yasunaga, G. and Pastene, L.A. 2019. Comparison of progesterone concentrations in blubber
and plasma among female Antarctic minke whales ofknown reproductive status. Fish Sci 85 (6): 971–977.
Tanabe, A., Shimizu, R., Osawa, Y., Suzuki, M., Ito, S.,
Goto, M., Pastene, L.A., Fujise, Y. and Sahara, H.
2019. Age estimation by DNA methylation in Antarctic minke whales. Fish Sci: https://doi.org/10.1007/
s12562-019-01371-7.

JARPN/JARPNII/NEWREP-NP surveys
1996 (3)Butterworth, D.S., Geromont H.F. and Wada S. 1996.
Further analysis of allele frequency data to provide
estimates of the extent of mixing between the various
North Paciﬁc minke whale stocks, and their implications for the status of the “O”stock. Rep. int. Whal.
Commn 46: 443–451.
Kuramochi, T., Machida, M., Araki, J., Uchida, A., Kishiro,
T. and Nagasawa, K. 1996. Minke whales (Balaenoptera acutorostrata) are one of the major ﬁnal hosts ofAnisakis simplex (Nematoda: Anisakidae) in the Northwestern North Paciﬁc Ocean. Rep. int. Whal. Commn
46: 415–419.
Miyashita, T. and Fujise, Y. 1996. Abundance estimate of
the western North Paciﬁc minke whale in sub-area 9
with notes on the results of dedicated surveys. Rep. int.
Whal. Commn 47: 543–551.
1997 (6)Aono, S., Tanabe, S., Fujise, Y., Kato, H. and Tatsukawa,R. 1997. Persistent organochlorines in minke whale(Balaenoptera acutorostrata) and their prey species
from the Antarctic and the North Paciﬁc. Environmental Pollution 98: 81–89.
Araki, J., Kuramochi, T., Machida, M., Nagasawa, K. andList of peer-reviewed publications based on the Institute of Cetacean Research (ICR)ʼs surveys up to 2019

Uchida, A. 1997. A note on the parasite fauna of thewestern North Paciﬁc minke whale (Balaenoptera acutorostrata). Rep. int. Whal. Commn 47: 565–567.
Goto, M. and Pastene, L.A. 1997. Population structureof western North Paciﬁc minke whale based on an
RFLP analysis of mtDNA control region. Rep. int. Whal.
Commn 47: 531–537.
Hatanaka, H. and Miyashita, T. 1997. On the feeding migration of the Okhotsk Sea-West Paciﬁc stock of minke
whales, estimates based on length composition data.
Rep. int. Whal. Commn 47: 557–564.
Hatanaka, H. 1997. A short review of hypotheses onminke whale stock structure in the Northwesternpart of the North Paciﬁc. Rep. int. Whal. Commn 47:
553–555.
Pastene, L.A., Goto, M., Itoh, S., Wada, S. and Kato, H.
1997. Intra- and inter-oceanic patterns of mitochondrial DNA variation in the Brydeʼs whale, Balaenoptera
edeni. Rep. int. Whal. Commn 47: 569–574.
1998 (4)
Lindstrøm, U., Fujise, Y., Haug, T. and Tamura, T. 1998.
Feeding habits of western North Paciﬁc minke whales,
Balaenoptera acutorostrata, as observed in JulySeptember 1996. Rep. int. Whal. Commn 48: 463–469.
Pastene, L.A., Goto, M. and Kishino, H. 1998. An estimateof mixing proportion of ʻJʼ and ʻOʼ stocks minke whales
in sub-area 11 based on mitochondrial DNA haplotype
data. Rep. int. Whal. Commn 48: 471–474.
Tamura, T., Fujise, Y. and Shimazaki, K. 1998. Diet of minke
whales Balaenoptera acutorostrata in the Northwestern part of the North Paciﬁc in summer 1994 and 1995.
Fish Sci 64 (1): 71–76.
Uchida, A., Kawakami, Y., Yuzu, S., Kishikawa, S., Kuramochi, T., Araki, J., Machida, M. and Nagasawa, K.
1998. Prevalence of parasites and histopathology ofparasitisation in minke whales (Balaenoptera acutorostrata) from the western North Paciﬁc Ocean andSouthern Sea of Okhotsk. Rep. int. Whal. Commn 48:
475–479.
1999 (2)Le, T.H.L., Takahashi, S., Saeki, K., Nakatani, N., Tanabe,S., Miyazaki, N. and Fujise, Y. 1999. High percentage ofbutyltin residues in total tin in the livers of cetaceansfrom Japanese coastal waters. Environmental Science& Technology 33 (11): 1781–1786.
Martinez, I. and Pastene, L.A. 1999. RAPD-typing ofcentral and eastern North Atlantic and western North
Paciﬁc minke whales, Balaenoptera acutorostrata. ICES

Journal of Marine Science 56 (5): 640–651.
2000 (2)Punt, A.E., Butterworth, D.S. and Wada, S. 2000. On theuse of allele frequency data within a Bayesian framework: evaluation of relative probabilities of alternative
stock structure hypotheses for North Paciﬁc minke
whales. J. Cetacean Res. Manage. 2 (2): 151–158.
Uchida, A. and Araki, J. 2000. The ectoparasites and endoparasites in the minke whale, Balaenoptera acutorostrata from the western North Paciﬁc Ocean. J. Jpn.
Vet. Med. Assoc. 53 (2): 85–88 (in Japanese).
2001 (1)Okamura, H., Matsuoka, K., Hakamada, T., Okazaki, M.
and Miyashita, T. 2001. Spatial and temporal structureof the western North Paciﬁc minke whale distribution
inferred from JARPN sightings data. J. Cetacean Res.
Manage. 3 (2): 193–200.
2002 (5)Abe, H. and Goto, M. 2002. The application of microsatellite DNA for determining population structure of minke
whale. pp. 109–113. In: Nishimura, A. (Ed). Technical
Reports of the Hokkaido National Fisheries ResearchInstitute No.5. Hokkaido National Fisheries ResearchInstitute, Hokkaido.
Cui, G., Punt, A.E., Pastene, L. A. and Goto, M. 2002.
Bayes and Empirical Bayes approaches to addressing
stock structure questions using mtDNA data, with anillustrative application to North Paciﬁc minke whales. J.
Cetacean Res. Manage. 4 (2): 123–134.
Ohsumi, S. and Tamura, T. 2002. Dietary studies on baleen whales in the North Paciﬁc. Fish Sci 68 (Suppl. I):
260–263.
Pastene, L.A., Goto, M. and Kanda, N. 2002. The utility of
DNA analysis for the management and conservation oflarge whales. Fish Sci 68 (Suppl. I): 286–289.
Tamura T. and Fujise Y. 2002. Geographical and seasonalchanges of the prey species of minke whale in the
Northwestern Paciﬁc. ICES Journal of Marine Science59 (3): 516–528.
2003 (4)Hayashi, K., Nishida, S., Yoshida, H., Goto, M., Pastene,
L.A. and Koike, H. 2003. Sequence variation of the DQB
allele in the cetacean MHC. Mammal Study 28 (2):89–96.
Nishida, S., Pastene, L.A., Goto, M. and Kanda, N. 2003.
SRY gene structure and phylogeny in the cetacean spe73

Technical Reports of the Institute of Cetacean Research (2019)cies. Mammal Study 28 (1): 57–66.
Nishida, S., Hayashi, K., Pastene, L.A., Goto, M., Kanda, N.
and Koike, H. 2003. Polymorphic analysis of cetacean
MHC - A case study on the minke whales -. Mammalian
Science (Suppl.) 3: 75–78 (in Japanese).
Ohishi, K., Zenitani, R., Bando, T., Goto, Y., Uchida, K.,
Maruyama, T., Yamamoto, S., Miyazaki, N. and Fujise, Y. 2003. Pathological and serological evidence of
Brucella-infection in baleen whales (Mysticeti) in thewestern North Paciﬁc. Comp. Immun. Microbiol. Infect.
Dis 26 (2): 125–136.
2004 (5)Kim, E.Y., Iwata, H., Fujise, Y. and Tanabe, S. 2004. Searching for novel CYP members using cDNA library from aminke whale liver. Marine Environmental Research 58:
495–498.
Ohishi. K., Takishita, K., Kawato, M., Zenitani, R., Bando,T., Fujise, Y., Goto, Y., Yamamoto, S. and Maruyama,
T. 2004. Molecular evidence of new variant Brucellain North Paciﬁc common minke whales. Microbes andInfection 6: 1199–1204.
Ohishi, K., Takishita, K., Kawato, M., Maruyama, T.,
Zenitani, R., Bando, T., Fujise, Y., Goto, Y. and Yamamoto, S. 2004. Molecular characterization of Brucellafrom North Paciﬁc common minke whale. Oceans'04:
499–504.
Watanabe, H., Mogoe, T., Asada, M., Hayashi, K., Fujise,Y., Ishikawa, H., Ohsumi, S., Miyamoto, A. and Fukui,
Y. 2004. Relationship between serum sex hormone
concentrations and histology of seminiferous tubulesof captured baleen whales in the western North Paciﬁcduring the feeding season. Journal of Reproduction andDevelopment 50 (4): 419–427.
Zharikov, K., Fujise, Y., Tamura, T., Kiwada, H., Bando, T.,
Konishi, K. and Isoda, T. 2004. Distribution and feedingof large cetaceans based on the data of JARPN II - 2003
May, 17-July, 9. Marine Mammals of the Holarctic
2004: 207–210.
2005 (5)Birukawa, N., Ando, H., Goto, M., Kanda, N., Pastene, L.A.,
Nakatsuji, H., Hata, H. and Urano, A. 2005. Plasma andurine levels of electrolytes, urea and steroid hormones
involved in osmoregulation of cetaceans. Zoological
Science 22 (11): 1245–1257.
Nikaido, M., Sasaki, T., Makino, H., Goto, M., Kanda, N.,
Pastene, L.A. and Okada, N. 2005. Phylogenetic reconstruction of baleen whales and detection of their pastextensive radiation event by the SINE insertion analy74

sis. Fossils 77: 22–28 (in Japanese).
Niimi, S., Watanabe, M.X., Kim, E.Y., Iwata, H., Yasunaga,G., Fujise, Y. and Tanabe, S. 2005. Molecular cloning
and mRNA expression of cytochrome P4501A1 and
1A2 in the liver of common minke whales (Balaenoptera acutorostrata). Marine Pollution Bulletin 51 (8):784–793.
Ohishi, K., Takishita, K., Kawato, M., Zenitani, R., Bando,T., Fujise, Y., Goto, Y., Yamamoto, S. and Maruyama,
T. 2005. Chimeric structure of omp2 of Brucella from
North Paciﬁc common minke whales (Balaenoptera
acutorostrata). Microbiol. Immunol. 49 (8): 789–793.
Sasaki, T., Nikaido, M., Hamilton, H., Goto, M., Kato, H.,
Kanda, N., Pastene, L.A., Cao, Y., Fordyce, R.E., Hasegawa, M. and Okada, N. 2005. Mitochondrial phylogenetics and evolution of mysticete whales. Systematic
Biology 54 (1): 77–90.
2006 (5)
Iwanami, K., Mita, H., Yamamoto, Y., Fujise, Y., Yamada,T. and Suzuki, T. 2006. cDNA-derived amino acid sequences of myoglobins from nine species of whales
and dolphins. Comparative Biochemistry and Physiology, Part B 145: 249–256.
Kanda, N., Goto, M. and Pastene, L.A. 2006. Genetic
characteristics of western North Paciﬁc sei whales,
Balaenoptera borealis, as revealed by microsatellites.
Marine Biotechnology 8: 86–93.
Mitani, Y., Bando., T., Takai., N. and Sakamoto, W. 2006.
Patterns of stable carbon and nitrogen isotopes in thebaleens of common minke whale Balaenoptera acutorostrata from the western North Paciﬁc. Fish Sci 72(1): 69–76.
Nikaido, M., Hamilton, H., Makino, H., Sasaki, T., Takahashi, K., Goto, M., Kanda, N., Pastene, L.A. and Okada,N. 2006. Baleen whale phylogeny and a past extensive
radiation event revealed by SINE insertion analysis.
Molecular Biology and Evolution 23 (5): 866–873.
Ohishi, K., Maruyama, T., Ninomiya, A., Kida, H., Zenitani,
R., Bando, T., Fujise, Y., Nakamatsu, K., Miyazaki, N. and
Boltunov, A.N. 2006. Serologic investigation of inﬂuenza a virus infection in cetaceans from the western
North Paciﬁc and the Southern Oceans. Marine Mammal Science 22 (1): 214–221.
2007 (11)
Fukui, Y., Iwayama, H., Matsuoka, T., Nagai, H., Koma,
N., Mogoe, T., Ishikawa, H., Fujise, Y., Hirabayashi, M.,
Hochi, S., Kato, H. and Ohsumi, S. 2007. Attempt at
intracytoplasmic sperm injection of in vitro matured

List of peer-reviewed publications based on the Institute of Cetacean Research (ICR)ʼs surveys up to 2019oocytes in common minke whales (Balaenoptera acutorostrata) captured during the Kushiro coast survey.
Journal of Reproduction and Development. 53 (4):945–952.
Kanda, N., Goto, M., Kato, H., McPhee, M.V. and Pastene,
L.A. 2007. Population genetic structure of Brydeʼswhales (Balaenoptera brydei) at the inter-oceanic andtrans-equatorial levels. Conservation Genetics 8 (4):853–864.
Konishi, K. and Tamura, T. 2007. Occurrence of the minimal armhook squids Berryteuthis anonychus (Cephalopoda: Gonatidae) in the stomachs of common minke
whales Balaenoptera acutorostrata in the western
North Paciﬁc. Fish Sci 73 (5): 1208–1210.
Murase, H., Tamura, T., Kiwada, H., Fujise, Y., Watanabe,
H., Ohizumi, H., Yonezaki, S., Okamura, H. and Kawahara, S. 2007. Prey selection of common minke (Balaenoptera acutorostrata) and Brydeʼs (Balaenoptera
edeni) whales in the western North Paciﬁc in 2000 and
2001. Fish. Oceanogr. 16 (2): 186–201.
Niimi, S., Kim, E.Y., Iwata, H., Watanabe, M.X., Yasunaga,G., Fujise, Y. and Tanabe, S. 2007. Identiﬁcation andhepatic expression proﬁles of cytochrome P450 1–4
isozymes in common minke whales (Balaenoptera acutorostrata). Comparative Biochemistry and Physiology,
Part B 147: 667–681.
Nishida, S., Goto, M., Pastene, L.A., Kanda, N. and Koike,
H. 2007. Phylogenetic relationships among cetaceansrevealed by Y-chromosome sequences. Zoological
Science 24 (7): 723–732.
Onbe, K. Nishida, S., Sone, E., Kanda, N., Goto, M., Pastene, L.A., Tanabe, S. and Koike, H. 2007. Sequencevariation in the Tbx4 Gene in marine mammals. Zoological Science 24 (5): 449–464.
Pastene, L.A., Goto, M., Kanda, N., Zerbini, A.N., Kerem,D., Watanabe, K., Bessho, Y., Hasegawa, M., Nielsen,
R., Larsen, F. and Palsbøll, P.J. 2007. Radiation andspeciation of pelagic organisms during periods ofglobal warming: the case of the common minke whale,
Balaenoptera acutorostrata. Molecular Ecology 16:1481–1495.
Urashima, T., Kobayashi, M., Asakuma, S., Uemura, Y.,
Arai, I., Fukuda, K., Saito, T., Mogoe, T., Ishikawa, H. andFukui, Y. 2007. Chemical characterization of the oligosaccharides in Brydeʼs whale (Balaenoptera edeni) andSei whale (Balaenoptera borealis) milk. Comparative
Biochemistry and Physiology, Part B 146: 153–159.
Watanabe, H., Tateno, H., Kusakabe, H., Kamiguchi, Y.,
Fujise, Y., Ishikawa, H., Ohsumi, S. and Fukui, Y. 2007.
Fertilizability and chromosomal integrity of frozen-

thawed Brydeʼs whale (Balaenoptera edeni) spermatozoa intracytoplasmically injected into mouse oocytes.
Reproduction, Fertility and Development 19 (1): 306.
Watanabe, H., Tateno, H., Kusakabe, H., Matsuoka, T.,
Kamiguchi, Y., Fujise, Y., Ishikawa, H., Ohsumi, S. andFukui, Y. 2007. Fertilizability and chromosomal integrityof frozen-thawed Brydeʼs whale (Balaenoptera edeni)
spermatozoa intracytoplasmically injected into mouse
oocytes. Zygote 15 (1): 9–14.
2008 (3)Birukawa, N., Ando, H., Goto, M., Kanda, N., Pastene,
L.A. and Urano, A. 2008. Molecular cloning of urea
transporters from the kidneys of baleen and toothed
whales. Comparative Biochemistry and Physiology,
Part B 149: 227–235.
Ishikawa, H. and Shigemune, H. 2008. Comparative experiment of whaling grenades in the Japanese Whale
Research Program under Special Permit (JARPA and
JARPN). Jpn. J. Zoo Wildl. Med. 13 (1): 21–28.
Ohishi, K., Fujise, Y. and Maruyama, T. 2008. Brucella spp.
in the western North Paciﬁc and Antarctic cetaceans: areview. J. Cetacean Res. Manage. 10 (1): 67–72.
2009 (9)Bhuiyan, M.M.U., Suzuki, Y., Watanabe, H., Hirayama, H.,
Matsuoka, K., Fujise, Y., Ishikawa, H., Ohsumi, S. andFukui, Y. 2009. Attempts at in vitro fertilization andculture of in vitro matured oocytes in sei (Balaenoptera
borealis) and Brydeʼs (B. edeni) whales. Zygote 17 (1):19–28.
Fujita, H., Honda, K., Hamada, N., Yasunaga, G and Fujise,
Y. 2009. Validation of high-throughput measurement
system with microwave-assisted extraction, fully automated sample preparation device, and gas chromatography-electron capture detector for determinationof polychlorinated biphenyls in whale blubber. Chemosphere 74: 1069–1078.
Hiwasa, M., Suzuki, Y., Watanabe, H., Bhuiyan, M.M.U.,
Matsuoka, K., Fujise, Y., Ishikawa, H., Ohsumi, S. andFukui, Y. 2009. Eﬀects of semen extenders and storage temperatures on characteristics of frozen-thawed
Brydeʼs (Balaenoptera edeni) whale spermatozoa. Journal of Reproduction and Development 55: 599–606.
Konishi, K., Tamura T., Isoda, T. Okamoto, R., Hakamada,T., Kiwada, H. and Matsuoka, K. 2009. Feeding strategies and prey consumption of three baleen whale species within the Kushiro-Current Extension. J. Northw.
Atl. Fish. Sci. 42: 27–40.
Lee, E., Bhuiyan, M.M.U., Watanabe, H., Matsuoka, K.,
75

Technical Reports of the Institute of Cetacean Research (2019)

Fujise, Y., Ishikawa, H. and Fukui. Y. 2009. Production ofcloned sei whale (Balaenoptera borealis) embryos byinterspecies somatic cell nuclear transfer using enucleated pig oocytes. J. Vet. Sci. 10 (4): 285–292.
Matsukura, R., Yasuma, H., Murase, H., Yonezaki, S., Funamoto, T., Honda, S. and Miyashita, K. 2009. Measurements of density contrast and sound-speed contrast
for target strength estimation of Neocalanus copepods(Neocalanus cristatus) in the North Paciﬁc Ocean. FishSci 75 (6): 1377–1387.
Murase, H., Ichihara, M., Yasuma, H., Watanabe, H., Yonezaki, S., Nagashima, H., Kawahara, S. and Miyashita, T.
2009. Acoustic characterization of biological backscatterings in the Kuroshio-Oyashio inter-frontal zone andsubarctic waters of the western North Paciﬁc in spring.
Fish. Oceanogr. 18 (6): 386–401.
Murase, H., Nagashima, H., Yonezaki, S., Matsukura, R.
and Kitakado, T. 2009. Application of a generalized additive model (GAM) to reveal relationships between
environmental factors and distributions of pelagic ﬁsh
and krill: a case study in Sendai Bay, Japan. ICES Journalof Marine Science 66 (6): 1417–1424.
Tsuki, K., Sato, A., Kaneko, H., Yasunaga, G., Fujise, Y. and
Nomata, H. 2009. Comparison of physiologically signiﬁcant imidazole dipeptides in cetaceans sampled inJapanese whale research (short paper). Sci. Rep. Hokkaido Fish. Exp. Stn. 74: 25–28 (in Japanese).
2010 (7)Bhuiyan, M.M.U., Suzuki, Y., Watanabe, H., Lee, E.,
Hirayama, H., Matsuoka, K., Fujise, Y., Ishikawa, H.,
Ohsumi, S. and Fukui, Y. 2010. Production of sei whale(Balaenoptera borealis) cloned embryos by inter- andintra-species somatic cell nuclear transfer. Journal of
Reproduction and Development 56: 131–139.
Funakasa, N., Yoshioka, M. and Fujise, Y. 2010. Featuresof the Ocular Harderian Gland in three Balaenopterid
species based on anatomical, histological and histochemical observations. Mammal Study 35 (1): 9–15.
Ogawa, G., Ishida, M., Kato, H., Fujise, H. and Urano, N.
2010. Identiﬁcation of facultative anaerobic bacteria
isolated from the intestine of the minke whale Balaenoptera acutorostrata by 16S rRNA sequencing analysis. Fish Sci 76 (2): 177–181.
Pastene, L.A., Fujise, Y. and Hatanaka, H. 2010. JARPNII: achallenging multidiscipline research program focusedon whales in the western North Paciﬁc. Ottar (TromsøMuseum) 280: 23–28 (in Norwegian)．
Shishido, R., Ohishi, K., Suzuki, R., Takishita, K., Ohtsu,
D., Okutsu, K., Tokutake, K., Katsumata, E., Bando, T.,76

Fujise, Y., Murayama, T. and Maruyama, T. 2010．Cetacean Toll-like receptor 4 and myeloid diﬀerentiation
factor 2, and possible cetacean-speciﬁc responses
against Gram-negative bacteria．Comp. Immun. Microbiol. Infect. Dis. 33 (6): 89–98．
Suzuki, Y., Umatani, M., Bhuiyan, M.M.U., Watanabe,H., Mogoe, T., Matsuoka, K., Fujise, Y., Ishikawa, H.,
Ohsumi, S., Sasaki, M. and Fukui, Y. 2010. Eﬀects ofequilibration steps, type of sugars and addition ofwhale follicular ﬂuid on viability and in vitro maturation of vitriﬁed whale oocytes．Jpn. J. Zoo Wildl. Med
15 (2): 65–72．
Tojo, N., Matsukura, R., Yasuma, H., Yonezaki, S., Watanabe, H., Kawahara, S., Murase, H. and Miyashita, K.
2010．Spatial analysis of isada krill (Euphausia paciﬁca)
distribution in frontal environments in the North Pacific Ocean．GIS/spatial analyses in ﬁsheries and aquatic
science．4．International Fishery GIS Society: 115–138.
2011 (20)
Hakamada, T. and Matsuoka, K. 2011. Abundance estimate for common minke, Brydeʼs and sei whales in theoﬀshore region of the western North Paciﬁc. Bull. Jpn.
Soc. Fish. Oceanogr. 75 (3): 173–174 (in Japanese).
Kanda, N., Goto, M. and Pastene, L. A. 2011. Genetic stock
structure of baleen whales. Bull. Jpn. Soc. Fish. Oceanogr. 75 (3): 191 (in Japanese).
Kato, H. and Fujise, Y. 2011. General discussion: Symposium on “Marine ecosystem of the western North Paciﬁc with special interest in cetaceans.” Bull. Jpn. Soc.
Fish. Oceanogr. 75 (3): 194–195 (in Japanese).
Kishiro, T., Yoshida, H., Tamura, T., Konishi, K., Kanda, N.,
Okamoto, R. and Kato, H. 2011. Relationship between
maturity and feeding ecology of common minke whales
oﬀ Kushiro in autumn. Bull. Jpn. Soc. Fish. Oceanogr. 75(3): 175–176 (in Japanese).
Maehara, T., Aoki, I., Yonezaki, S., Watanabe, H., Murase,
H. and Yamaguchi, A. 2011. Feeding ecology of theJapanese anchovy in the oﬀshore area east of Honshu,
Japan in summer. Bull. Jpn. Soc. Fish. Oceanogr. 75 (3):187 (in Japanese).
Matsuoka, K., Kiwada, H., Fujise, Y. and Miyashita, T. 2011.
Distribution of baleen whales in the western North Paciﬁc based on the JARPN and JARPN II sighting surveys(1994 to 2007). Bull. Jpn. Soc. Fish. Oceanogr. 75 (3):178–179 (in Japanese).
Miyashita, K., Matsukura, R., Tojo, N., Minami, K.,
Yasuma, H., Nagashima, H., Onodera, K., Watanabe, H.,
Yonezaki, S. and Murase, H. 2011. Monitoring of preyof cetaceans by using quantitative echosounders. Bull.

List of peer-reviewed publications based on the Institute of Cetacean Research (ICR)ʼs surveys up to 2019

Jpn. Soc. Fish. Oceanogr. 75 (3): 183–184 (in Japanese).
Mori, M., Watanabe, H., Hakamada, T., Tamura, T., Konishi, K., Murase, H. and Matsuoka, K. 2011. Development of an ecosystem model of western North Paciﬁcusing Ecopath with Ecosim. Bull. Jpn. Soc. Fish. Oceanogr. 75 (3): 189 (in Japanese).
Murase, H., Kawabata, A., Kubota, H., Nakagami, M.,
Amakasu, K., Abe, K., Miyashita, K. and Oozeki, Y. 2011.
Eﬀect of depth-dependent target strength on biomass
estimation of Japanese anchovy. Journal of Marine
Science and Technology 19: 267–272.
Murase, H., Tamura, T., Isoda, T., Okamoto, R., Kato, H.,
Yonezaki, S., Watanabe, H., Tojo, N. Matsukura, R.,
Miyashita, K., Kiwada, H., Matsuoka, K., Nishiwaki, S.,
Inagake, D., Okazaki, M., Okamura, H. and Fujise, Y.
2011. Prey selection of common minke, Brydeʼs andsei whales in the oﬀshore region of the western North
Paciﬁc. Bull. Jpn. Soc. Fish. Oceanogr. 75 (3): 180–181(in Japanese).
Nishiwaki, S., Otani, S. and Tamura, T. 2011. The satellite
tracking of the western North Paciﬁc. Bull. Jpn. Soc.
Fish. Oceanogr. 75 (3): 193–194 (in Japanese).
Onodera, K., Nagashima, H., Matsukura, R., Miyashita,K., Yonezaki, S. and Murase, H. 2011. Cetacean preyspecies and oceanographic surveys in Sendai Bay. Bull.
Jpn. Soc. Fish. Oceanogr. 75 (3): 184–185 (in Japanese).
Pastene, L.A., Hatanaka, H., Fujise, Y., Kanda, N., Murase,
H., Tamura, T., Miyashita, T. and Kato, H. 2011. Whale
research program under special permit in the western
North Paciﬁc—Phase II (JARPNII): origin and objectives. Bull. Jpn. Soc. Fish. Oceanogr. 75 (3): 172–173 (inJapanese).
Pastene, L.A., Hatanaka, H., Fujise, Y., Kanda, N., Murase,
H., Tamura, T., Yasunaga, G., Kishiro, T., Yoshida, H.,
Miyashita, T. and Kato, H. 2011. The Japanese Whale
Research Program under Special Permit in the western
North Paciﬁc Phase-II (JARPNII): origin, objectives andresearch progress made in the ﬁrst six years period(2002–2007), including scientiﬁc considerations for the
next research period. Aquabiology 33 (2): 171–185 (inJapanese).
Sasaki, Y., Saito, S., Matsuoka, K., Murase, H. and Kiwada.,
H. 2011. Spatial distribution patterns of sei and Brydeʼswhales. Bull. Jpn. Soc. Fish. Oceanogr. 75 (3): 179–180(in Japanese).
Tamura, T., Konishi, K., Isoda, T., Hakamada, T., Kiwada, H.,
Okamoto, R. and Matsuoka, K. 2011. The food habitat,
relation of habitat factor and prey consumption of
three baleen whale species in the oﬀshore region of
the western North Paciﬁc. Bull. Jpn. Soc. Fish. Ocean-ogr. 75 (3): 174–175 (in Japanese).
Watanabe, H., Kiwada, H., Kumagai, S., Yonezaki, S.,
Kishiro, T., Konishi., K. and Yoshida, H. 2011. Habitatand prey selection of common minke whale oﬀ Kushiro
in autumn—Estimation of distribution and migrationof common minke whale using environmental information—Bull. Jpn. Soc. Fish. Oceanogr. 75 (3): 182–183 (inJapanese).
Yamaguchi, A., Hanamiya, Y., Murase, H. and Watanabe,
H. 2011. Vertical ﬂux of materials by diel vertical migration of macrozooplankton. Bull. Jpn. Soc. Fish. Oceanogr. 75 (3): 185–186 (in Japanese).
Yasunaga, G. and Fujise, Y. 2011. Monitoring of pollutants in the baleen whales and their prey species in thewestern North Paciﬁc. Bull. Jpn. Soc. Fish. Oceanogr. 75(3): 190 (in Japanese).
Yoshida, H., Kishiro, T., Goto, M., Bando, T., Tamura, T.,
Konishi, K., Okamoto, R. and Kato, H. 2011. Feeding
ecology of common minke whales in coastal waters oﬀ
Sanriku in spring. Bull. Jpn. Soc. Fish. Oceanogr. 75 (3):
177–178 (in Japanese).
2012 (4)Maeda, H. and Kato, H. 2012. Technical improvementsof the age character (earplug) collections in common
minke whales. Bull. Jpn. Soc. Fish. Oceanogr. 76 (2):59–65 (in Japanese).
Murase, H., Kawabata, A., Kubota, H., Nakagami, M.,
Amakasu, K., Abe, K., Miyashita, K. and Oozeki, Y. 2012.
Basin-scale distribution patterns and biomass estimation of Japanese anchovy Engraulis japonicus in thewestern North Paciﬁc. Fish Sci 78 (4): 761–773.
Nakamura, G., Kato, H. and Fujise, Y. 2012. Relative
growth of the skull of the common minke whale Balaenoptera acutorostrata from the North Paciﬁc in comparison to other Balaenoptera species. Mammal Study
37 (2): 105–112.
Watanabe, H, Okazaki, M., Tamura, T., Konishi, K., Inagake, D., Bando, T., Kiwada, H. and Miyashita, T. 2012.
Habitat and prey selection of common minke, sei, andBrydeʼs whale in mesoscale during summer in the
sub-arctic and transition regions of the western North
Paciﬁc. Fish Sci 78 (3): 557–567.
2013 (5)*Kershaw, F., Leslie, M.S., Collins, T., Mansur, R.M., Smith,B.D., Minton, G., Baldwin, R., LeDuc, R.G., Anderson,
R.C., Brownell, R.L. and Rosenbaum, H.C. 2013. Population diﬀerentiation of 2 forms of Brydeʼs whales in the
Indian and Paciﬁc Oceans. Journal of Heredity 104 (6):77Technical Reports of the Institute of Cetacean Research (2019)755–764.
Maeda, H., Kawamoto, T. and Kato, H. 2013. A study on
the improvement of age estimation in common minke
whales using the method of gelatinized extraction of
earplug. NAMMCO Scientiﬁc Publications 10: 17pp.
Matsukura, R., Sawada, K., Abe, K., Minami, K., Nagashima, H., Yonezaki, S., Murase, H. and Miyashita,
K. 2013. Comparison of measurements and model
calculations of target strength of juvenile sandeel in
Sendai Bay. Nippon Suisan Gakkaishi 79 (4): 638–648(in Japanese).
Sasaki, H., Murase, H., Kiwada, H., Matsuoka, K., Mitani, Y.
and Saitoh, S. 2013. Habitat diﬀerentiation between sei(Balaenoptera borealis) and Brydeʼs whales (B. brydei)
in the western North Paciﬁc. Fish. Oceanogr. 22 (6):496–508.
Shimizu, Y., Ohishi, K., Suzuki, R., Tajima, Y., Yamada, T.,
Kakizoe, Y., Bando, T., Fujise, Y., Taru, H., Murayama, T.
and Maruyama, T. 2013. Amino acid sequence variations of signaling lymphocyte activation molecule andmortality caused by morbillivirus infection in cetaceans. Microbiol Immunol 57: 624–632.
2014 (6)Inoue, S., Kishiro, T., Fujise, Y., Nakamura, G. and Kato,
H. 2014. Seasonal changes in the testis of the North
Paciﬁc common minke whale. Nippon Suisan Gakkaishi
80 (2): 185–190 (in Japanese).
Murase, H., Hakamada, T., Matsuoka, K., Nishiwaki, S.,
Inagake, D., Okazaki, M., Tojo, N. and Kitakado, T. 2014.
Distribution of sei whales (Balaenoptera borealis) in
the subarctic–subtropical transition area of the western North Paciﬁc in relation to oceanic fronts. Deep
Sea Research Part II: Topical Studies in Oceanography
107: 22–28.
Nakamura, G., Kadowaki, I., Nagatsuka, S., Fujise, Y.,
Kishiro, T. and Kato, H. 2014. Variation in a color pattern of white patch on the ﬂippers of North Paciﬁc
common minke whales: potential application for theirinteroceanic diﬀerence. La mer 52: 31–47.
Nakamura, G. and Kato, H. 2014. Developmental changes
in the skull morphology of common minke whales
Balaenoptera acutorostrata. Journal of Morphology
275: 1113–1121.
Niimi, S., Imoto, M., Kunisue, T., Watanabe, M.X., Kim,
E.Y., Nakayama, K., Yasunaga, G., Fujise, Y., Tanabe, S.
and Iwata, H. 2014. Eﬀects of persistent organochlorine exposure on the liver transcriptome of the common minke whale (Balaenoptera acutorostrata) fromthe North Paciﬁc. Ecotoxicology and Environmental
78

Safety 108: 95–105.
*Rosel, P.E. and Wilcox, L.A. 2014. Genetic evidence reveals a unique lineage of Brydeʼs whales in the northern Gulf of Mexico. Endang Species Res. 25 : 19–34.
2015 (1)Kitayama, C., Sasaki, M., Ishikawa, H., Mogoe, T., Ohsumi,
S., Fukui, Y., Budipitojo, T., Kondoh, D. and Kitamura, N.
2015. Structure and functions of the placenta in common minke (Balaenoptera acutorostrata), Brydeʼs (B.
brydei) and sei (B. borealis) whales. Journal of Reproduction and Development 61 (5): 415–421.
2016 (6)Hirako, S., Suzuki, M., Kim, H., Iizuka, Y., Matsumoto,A., Wada, N., Okabe, M., Takenoya, F., Yasunaga, G.,
Yamanaka, S., Miyazaki, A. and Shioda, S. 2016. Hepatic
lipid accumulation is ameliorated in obese KK mice by
dietary sei whale oil. Fish Sci 82 (3): 509–517.
Miyakawa, N., Kishiro, T., Fujise, Y., Nakamura, G. andKato, H. 2016. Sexual Dimorphism in Pelvic Bone
Shape of the North Paciﬁc Common Minke Whales(Balaenoptera acutorostrata). Open Journal of Animal
Sciences 6: 131–136.
Murase, H., Tamura, T., Otani, S. and Nishiwaki, S. 2016.
Satellite tracking of Brydeʼs whales Balaenoptera edeni
in the oﬀshore western North Paciﬁc in summer 2006
and 2008. Fish Sci 82 (1): 35–45.
Nakamura, G., Kadowaki, I., Nagatsuka, S., Hayashi, R.,
Kanda, N., Goto, M., Pastene, L.A. and Kato, H. 2016.
White Patch on the Fore-Flipper of Common Minke
Whale, as a Potential morphological Index to Identify
Stocks. Open Journal of Animal Sciences 6: 116–122.
Nakamura, G., Takahashi, M., Hirose, A., Hayashi, R.,
Fujise, Y., Miyakawa, N., Inoue, S. and Kato, H. 2016.
Presence of an interparietal bone and morphologicalvariation in the vertex of the skull in North Paciﬁc common minke whale. La mer 54 (1): 1–10.
Ohishi, K., Bando, T., Abe, E., Kawai, Y., Fujise, Y. andMaruyama, T. 2016. Long-term and large-scale epidemiology of Brucella infection in baleen whales andsperm whales in the western North Paciﬁc and Antarctic Oceans. J. Vet. Med. Sci. 78 (9): 1457–1464.
2017 (2)Bando, T., Nakamura, G., Fujise, Y. and Kato, H. 2017.
Developmental changes in the morphology of western
North Paciﬁc Brydeʼs whales (Balaenoptera edeni).
Open Journal of Animal Sciences 7: 344–355.
Ishii, M., Murase, H., Fukuda, Y., Sawada, K., Sasakura,

List of peer-reviewed publications based on the Institute of Cetacean Research (ICR)ʼs surveys up to 2019

T., Tamura, T., Bando, T., Matsuoka, K., Shinohara, A.,
Nakatsuka, S., Katsumata, N., Okazaki, M., Miyashita,
K. and Mitani, Y. 2017. Diving behavior of sei whales
Balaenoptera borealis relative to the vertical distribution of their potential prey. Mammal Study 42 (4):
191–199.
2018 (4)Hirose, A., Kishida, T. and Nakamura, G. 2018. Nasal mucosa resembling an olfactory system in the common
minke whale (Balaenoptera acutorostrata). Cetacean
Population Studies 1: 25–28.
Huijser, L.A.E., Bérubé, M., Cabrera, A.A., Prieto, R., Silva,
M.A., Robbins, J., Kanda, N., Pastene, L.A., Goto, M.,
Yoshida, H., Vikingsson, G.A. and Palsbøll, P.J. 2018.
Population structure of North Atlantic and North Paciﬁc sei whales (Balaenoptera borealis) inferred frommitochondrial control region DNA sequences and microsatellite genotypes. Conserv Genet 19: 1007–1024.
Nakamura, G., Ryeng, K.A., Kadowaki, I., Hayashi, R.,
Nagatsuka, S., Hirose, A., Fujise, Y. and Haug, T. 2018.
Comparison of shapes of the white ﬂipper patch
between two sub-species of common minke whales(Balaenoptera acutorostrata). Cetacean Population
Studies 1: 15–24.
Watari, S., Murase, H., Yonezaki, S., Okazaki, M., Kiyofuji,
H., Tamura, T., Hakamada, T., Kanaji, Y. and Kitakado, T.
2018. Ecosystem modeling in the western North Paciﬁcusing Ecopath, with a focus on small pelagic ﬁshes.
Mar. Ecol. Prog. Ser. 617–618: 295–305.

ka, K. 1997. Sounds attributed to blue whales recorded
oﬀ the southwest coast of Australia in December 1995.
Rep. int. Whal. Commn 47: 435–439.
Ohmagari, K. and Berkes, F. 1997. Transmission of indigenous knowledge and bush skills among the WesternJames Bay Cree Women of Subarctic Canada. Human
Ecology 25 (2): 197–222.
Shimamura, M., Yasue, H., Ohshima, K., Abe, H., Kato, H.,
Kishiro, T., Goto, M., Munechika, I. and Okada, N. 1997.
Molecular evidence from retroposons that whales
form a clade within even-toed ungulates. Nature 388:
666–670.
1998 (2)Miyazaki, N., Fujise, Y. and Iwata, K. 1998. Biologicalanalysis of a mass stranding of melon-headed whales(Peponocephala electra) at Aoshima. Japan. Bull. Natn.
Sci. Mus., Tokyo, Ser. A 24 (1): 31–60.
Otani, S., Naito, Y., Kawamura, A., Kawasaki, M., Nishiwaki, S. and Kato, A. 1998. Diving behavior and performance of harbor porpoises, Phocoena phocoena,
in Fukuoka bay, Hokkaido, Japan. Marine Mammal
Science 14 (2): 209–220.

1995 (1)Shimada, H. and Pastene, L.A. 1995. Report of a sightings survey oﬀ the Solomon Islands with comments on
Brydeʼs whale distribution. Rep. int. Whal. Commn 45:
413–418.

1999 (4)Iino, Y. 1999. Treaty Implementation: the 1946 International Convention for the Regulation of Whaling.
System Compliance in Ocean Management. Southeast
Asian Programme in Ocean Law. Policy and Management: 189–193.
Pastene, L.A. and Shimada, H. 1999. Report of a sighting
survey in Chileʼs Exclusive Economic Zone with comments on sei whale distribution. Anales Instituto Patagonia, Serie Cs. Nat. 27: 51–62.
Shimamura, M., Abe, H., Nikaido, M., Ohshima, K. andOkada, N. 1999. Genealogy of families of SINEs in cetaceans and artiodactyls: the presence of a huge superfamily of tRNAGlu-derived families of SINEs. Mol. Biol.
Evol. 16 (8): 1046–1060.
Yoshida, H. and Kato, H. 1999. Phylogenetic relationshipsof Brydeʼs whales in the Western North Paciﬁc andadjacent waters inferred from mitochondrial DNA sequences. Marine Mammal Science 15 (4): 1269–1286.

1997 (4)Kimura, T., Ozawa, T. and Pastene, L.A. 1997. Sample
preparation and analysis of mitochondrial DNA fromwhale baleen plates. Marine Mammal Science 13 (3):495–498.
Ljungblad, D.K., Staﬀord, K.M., Shimada, H. and Matsuo-

2000 (3)Goto, M. and Ohsumi, S. 2000. Response to “Scientiﬁc
Whaling Source of illegal Products for Market” By Baker
et al. Science 290: 1695–1696.
Otani, S., Naito, Y., Kato, A. and Kawamura, A. 2000. Diving behavior and swimming speed of a free-ranging

Other surveys
1993 (1)Fujise, Y., Ishikawa, H., Saino, S. and Kawasaki, M. 1993.
Catch and struck-and-lost rate in the Japanese Dallʼs
porpoise hand-harpoon ﬁshery. Rep. int. Whal. Commn
43: 453–457.

79

Technical Reports of the Institute of Cetacean Research (2019)

harbor porpoise, Phocoena phocoena. Marine Mammal Science 16 (4): 811–814.
Takahashi, S., Le, L.T.H., Saeki, H., Nakatani, N., Tanabe,S., Miyazaki, N. and Fujise, Y. 2000. Accumulation ofbutyltin compounds and total tin in marine mammals.
Water Science and Technology 42 (7–8): 97–108.
2001 (2)Abe, H., Goto, M., Pastene, L.A., Dewa, K. and Naito, E.
2001. Practical use of multiplex ﬂuorescent PCR for
cetacean sex identiﬁcation. Marine Mammal Science
17 (3): 657–664.
Yoshida, H., Yoshioka, M., Shirakihara, M. and Chow, S.
2001. Population structure of ﬁnless porpoises (Neophocaena phocaenoides) in coastal waters of Japan
based on mitochondrial DNA sequences. Journal of
Mammalogy 82 (1): 123–130.
2002 (1)Konishi, K. and Sakurai, Y. 2002. Geographical variations ininfection by larval Anisakis simplex and Contracaecum
osculatum (Nematoda, Anisakidae) in walleye pollock
Theragra chalcogramma stocks oﬀ Hokkaido, Japan.
Fish Sci 68 (3): 534–542.
2003 (1)Matsuoka, K., Ensor, P., Hakamada, T., Shimada, H., Nishiwaki, S., Kasamatsu, F. and Kato, H. 2003. Overview
of the minke whale sighting survey in IWC/IDCR and
SOWER cruises from 1978/79 to 2000/01. J. Cetacean
Res. Manage. 5 (2): 173–201.
2004 (5)Branch, T.A., Matsuoka, K. and Miyashita, T. 2004. Evidence for increases in Antarctic blue whales based on
Bayesian modelling. Marine Mammal Science 20 (4):726–754.
Escorza-Trevino, S., Pastene, L.A. and Dizon, A.E. 2004.
Molecular analyses of the Truei and Dalli morphotypes of Dallʼs porpoise (Phocoenoides dalli). Journal of
Mammalogy 85 (2): 347–355.
Ikemoto, T., Kunito, T., Watanabe, I., Yasunaga, G., Baba,N., Miyazaki, N., Petrov, E.A. and Tanabe, S. 2004.
Comparison of trace element accumulation in Baikal
seals (Pusa sibirica), Caspian seals (Pusa caspica) andnorthern fur seals (Callorhinus ursinus). Environmental
Pollution 127: 83–97.
Murase, H., Matsuoka, K., Nishiwaki, S., Hakamada, T. andMori, M. 2004. Eﬀect of observed covariates (school
size, sighting cue, latitude and sea state) on the Antarc80

tic minke whale abundance estimation parameters in
the IWC/IDCR-SOWER surveys. J. Cetacean Res. Manage. 6 (3): 283–292.
Yanagimoto, T. and Konishi, K. 2004. Acanthochondria priacanthi (Copepoda: Chondracanthidae) as a biologicalindicator for stock identiﬁcation of sandﬁsh Arctoscopus japonicus (Steindachner). Fish Sci 70 (2): 336–338.
2005 (5)Agusa, T., Matsumoto, T., Ikemoto, T., Anan, Y., Kubota, R.,
Yasunaga, G., Kunito, T., Tanabe, S., Ogi, H. and Shibata,Y. 2005. Body distribution of trace elements in blacktailed gulls from Rishiri Island, Japan: age-dependentaccumulation and transfer to feathers and eggs. Environ. Toxicol. Chem. 24 (9): 2107–2120.
Agusa, T., Kunito, T., Yasunaga, G., Iwata, H., Subramanian, A., Ismail, A. and Tanabe, S. 2005. Concentrationsof trace elements in marine ﬁsh and its risk assessment in Malaysia. Marine Pollution Bulletin 51 (8–12):
896–911.
Fukui, Y., Ishikawa, H. and Ohsumi, S. 2005. Diﬃculties
in publishing research results from scientiﬁc whaling.
Marine Mammal Science 21 (4): 781–783.
Prudente, M., Tanabe, S., Kunisue, T., Yasunaga, G., Watanabe, I. and Miyazaki, N. 2005. Accumulation of traceelements and persistent organochlorines in resident
and migratory waders from Calatagan Bay, Philippines.
Coastal Marine Science 29 (2): 133–140.
Sanino, G.P., Waerebeek, K.V., Van Bressem, M. andPastene, L.A. 2005. A preliminary note on population
structure in eastern South Paciﬁc common bottlenose
dolphins, Tursiops truncatus. J. Cetacean Res. Manage.
7 (1): 65–70.
2006 (6)Acevedo, J., Aguayo-Lobo, A. and Pastene, L.A. 2006.
Filopatria de la ballena jorobada (Megaptera novaeangliae Borowski, 1781), al area de alimentacion delEstrecho de Magallanes. Revista de Biologia Marina y
Oceanograﬁa 41 (1): 11–19.
Acevedo, J., Aguayo-Lobo, A., Acuna, P. and Pastene, L.A.
2006. A note on the ﬁrst record of the dwarf minke
whale (Balaenoptera acutorostrata) in Chilean waters.
J. Cetacean Res. Manage. 8 (3): 293–296.
Hayashi, K., Yoshida, H., Nishida, S., Goto, M., Pastene,
L.A., Kanda, N., Baba, H. and Koike, H. 2006. Genetic
Variation of the MHC DQB locus in the ﬁnless porpoise(Neophocaena phocaenoides). Zoological Science 23(2): 147–153.
Mori, M. and Butterworth, D.S. 2006. A ﬁrst step towards

List of peer-reviewed publications based on the Institute of Cetacean Research (ICR)ʼs surveys up to 2019modelling the krill–predator dynamics of the Antarctic
ecosystem. CCAMLR Science 13: 217–277.
Sekiguchi, K., Olavarria, C., Morse, P., Olson, P., Ensor,
P., Matsuoka, K., Pitman, R., Findlay, K. and Gorter, U.
2006. The spectacled porpoise (Phocoena dioptrica)
in Antarctic waters. J. Cetacean Res. Manage. 8 (3):265–271.
Takahashi, Y., Ohwada, S., Watanabe, K., Ropert-Coudert,Y., Zenitani, R., Naito, Y. and Yamaguchi, T. 2006. Does
elastin contribute to the persistence of corpora albicantia in the ovary of the common dolphin (Delphinusdelphis). Marine Mammal Science 22 (4): 819–830.
2007 (2)Acevedo, J., Rasmussen, K., Felix, F., Castro, C., Llano, M.,
Secchi, E., Saborio, M.T., Aguayo-Lobo, A., Haase, B.,
Scheidat, M., Dalla-Rosa, L., Olavarria, C., Fosestell, P.,
Acuna, P., Kaufman, G. and Pastene, L.A. 2007. Migratory destinations of humpback whales from the Magellan Strait feeding ground, Southeast Paciﬁc. Marine
Mammal Science 23 (2): 453–463.
Branch, T.A., Staﬀord, K.M., Palacios, D.M., Allison, C.,
Bannister, J.L., Burton, C.L.K., Cabrera, E., Carlson, C.A.,
Galletti Vernazzani, B., Gill, P.C., Hucke-Gaete, R., Jenner, K.C.S., Jenner, Mn. M., Matsuoka, K., Mikhalev,
Y.A., Miyashita, T., Morrice, M.G., Nishiwaki, S., Sturrock, V.J., Tormosov, D., Anderson, R.C., Baker, A.N.,
Best, P.B., Borsa, P., Brownell Jr, R.L., Childerhouse,
S., Findlay, K.P., Gerrodette, T., Ilangakoon, A.D., Joergensen, M., Kahn, B., Ljungblad, D.K., Maughan, B.,
Mccauley, R.D., Mckay, S., Norris, T.F., Oman Whaleand Dolphin Research Group, Rankin, S., Samaran, F.,
Thiele, D., Van Waerebeek, K. and Warneke, R.M. 2007.
Past and present distribution, densities and movements of blue whales in the Southern Hemisphere andadjacent waters. Mammal Rev. 37 (2): 116–175.
2009 (1)Nambu, H., Tokutake, K., Ishikawa, H., Ohta, M., Fujita, K.
and Yamada, T.K. 2009. Observation of a gray whale,
Eschrichtius robustus, in Tokyo Bay in 2005. Japan Cetology 19: 17–22 (in Japanese).
2010 (3)Nambu, H., Ishikawa, H. and Yamada, T. 2010. Recordsof the western gray whale Eschrichtius robustus: its
distribution and migration. Japan Cetology 20: 21–29(in Japanese).
Pastene, L.A. and Quiroz, D. 2010. An Outline of the History of Whaling in Chile. pp. 73–98. In: International

Center for Folk Culture Studies (Ed). Human Culture
from the Perspective of Traditional Maritime Communities, International Symposium Report No. 1. Kanagawa
Shimbun Press, Kanagawa. 199pp.
Taguchi, M., Ishikawa, H. and Matsuishi, T. 2010. Seasonal
distribution of harbour porpoise (Phocoena phocoena)
in Japanese waters inferred from stranding and bycatchrecords．Mammal Study 35 (2) : 133–138．
2011 (2)Acevedo, J., Olavarría, C., Plana, J., Aguayo-Lobo, A., Larrea, A. and Pastene, L.A. 2011. Occurrence of dwarf
minke whales (Balaenoptera acutorostrata subsp.)
around the Antarctic Peninsula. Polar Biol 34 (2):313–318.
Acevedo, J., Plana, J., Aguayo-Lobo, A. and Pastene, L.A.
2011. Surface feeding behavior of humpback whalesin the Magellan Strait. Revista de Biologia Marina y
Oceanograﬁa. 46 (3): 483–490.
2013 (4)Acevedo J., Haro D., Dalla R.L., Aguayo-Lobo A., HuckeGaete R., Secchi E., Plana J. and Pastene L.A. 2013.
Evidence of spatial structuring of eastern South Paciﬁchumpback whale feeding grounds. Endang Species Res
22 (1): 33–38.
Kitamura, S., Matsuishi, T., Yamada, K., Tajima, Y., Ishikawa, H., Tanabe, S., Nakagawa, H., Uni, Y. and Abe, S.
2013. Two genetically distinct stocks in Bairdʼs beaked
whale (Cetacea: Ziphiidae). Marine Mammal Science
29 (4): 755–766.
Murase, H., Temoai, I., Kirata, T., Finkaso, S., Yasunaga, G.
and Pastene, L.A. 2013. A note on cetaceans oﬀ Kiribati
and Tuvalu from a research cruise in October 2010. J.
Cetacean Res. Manage. 13 (2): 153–158.
Sugino, T., Yasunaga, G. and Fukuda, M. 2013. Eﬀect ofwhale meat extract on fatigue induced by physical load
and by daily activities in humans. Jpn. Pharmacol. Ther
41 (9): 879–893 (in Japanese).
2014 (3)Pastene, L.A. 2014. Macaya Hermanos y Compania.
Notas sobre las actividades de la empresa ballenerade más larga historia en Chile. Colección Mocha Dick
pp 255–274.
Quiroz, D. and Pastene, L.A. 2014. Norwegian whaling inChile in the 20th Century and its inﬂuence on Chilean
local communities. pp. 61–70. In: Jan Erik Ringstad(Ed). Whaling and History IV. Commander Chr. Christensenʼs Whaling Museum, part of Vestfoldmuseene81

Technical Reports of the Institute of Cetacean Research (2019)

IKA, Sandefjord. 192pp.
Quintela, M., Skaug, H.J., Øien, N., Haug, T., Seliussen,
B.B., Solvang, H.K., Pampoulie, C., Kanda, N., Pastene,
L.A. and Glover, K.A. 2014. Investigating population genetic structure in a highly mobile marine organism: theminke whale Balaenoptera acutorostrata acutorostrata in the North East Atlantic. PLoS ONE 9 (9): e108640.
2015 (3)Funasaka, N., Kirihata, T., Kato, H. and Ohsumi, S. 2015.
The ﬁrst record of a true albino common bottlenose
dolphin Tursiops truncatus from Japan. Mammal Study
40 (1): 19–22.
Pastene, L.A., Acevedo, J., Siciliano, S., Sholl, T.G.C., de
Moura, J.F., Ott, P.H. and Aguayo-Lobo, Anelio. 2015.
Population genetic structure of the South American
Brydeʼs whale. Revista de Biologia Marina y Oceanograﬁa 50 (3): 453–464.
Sakamoto, M., Itai, T., Yasutake, A., Iwasaki, T., Yasunaga,G., Fujise, Y., Nakamura, M., Murata, K., Chan, H.M.,
Domingog, J.L. and Marumoto, M. 2015. Mercury
speciation and selenium in toothed-whale muscles.
Environmental Research 143: 55–61.
2017 (3)Funasaka, N., Kirihata, T., Hosono, M., Kato, K. andOhsumi, S. 2017. Three Cases of Anomalously White
Rissoʼs Dolphins Grampus griseus in Japan. Mammal
Study 42 (3): 173–178.

82

Hakamada, T., Matsuoka, K., Murase, H. and Kitakado, T.
2017. Estimation of the abundance of the sei whale
Balaenoptera borealis in the central and eastern North
Paciﬁc in summer using sighting data from 2010 to2012. Fish Sci 83 (6): 887–895.
Malde, K., Seliussen, B.B., Quintela, M., Dahle, G., Besnier,F., Skaug, H.J., Øien, N., Solvang, H.K., Haug, T., SkernMauritzen, R., Kanda, N., Pastene, L.A., Jonassen, I. andGlover, K.A. 2017. Whole genome resequencing reveals diagnostic markers for investigating global migration and hybridization between minke whale species.
BMC Genomics 18: 76.
2019 (3)Kawasaki, K., Mikami, M., Goto, M., Shindo, J., Amano,
M. and Ishiyama, M. 2019. The Evolution of Unusually
Small Amelogenin Genes in Cetaceans; Pseudogenization, X–Y Gene Conversion, and Feeding Strategy. Journal of Molecular Evolution: https://doi.org/10.1007/
s00239-019-09917-0.
Pastene, L.A., Acevedo, J., Branch, T.A. 2019. Morphometric analysis of Chilean blue whales and implications fortheir taxonomy. Marine Mammal Science: https://doi.
org/10.1111/mms.12625.
Takahashi, M., Kato, H. and Kitakado, T. 2019. Sex prediction by machine learning methods for small sample
sizes: a case study of cranial measurements of killer
whales (Orcinus orca). Mammalian Science 59 (1):67–78 (in Japanese).

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