SC/67a/ASI

Result of the Japanese dedicated cetacean sighting survey
in the western North Pacific in 2016
KOJI MATSUOKA1, TAKASHI HAKAMADA1 RYUICHIRO MORIYAMA 2, HIROYA MURE 2, NOBUO ABE 2,
CHIKAMASA OHKOSHI2 AND TOMIO MIYASHITA3
1

Institute of Cetacean Research, Toyomi 4-5, Chuo-ku Tokyo, 104-0055, JAPANKyodo Senpaku Co. Ltd., Toyomi 4-5, Chuo-ku Tokyo, 104-0055, JAPAN3
National Research Institute of Far Seas Fisheries, Fukuura 2-12-4, Kanazawa, Yokohama, Kanagawa
236-8648, JAPAN
2

Contact e-mail: matsuoka@cetacean.jp

ABSTRACT
A systematic large-scale and vessel-based sighting survey was conducted in 2016 by Japan to examine the
distribution and abundance of large whales in the western North Pacific. The research area was set between
35° N and 43° N and between 140° E and 150° E (sub-areas 7CN, 7CS, 7WR and 7E for common minke
whale). The survey was conducted between 29 July and 6 September. The research vessels Yushin-Maru andYushin-Maru No.2 were engaged for this survey. A total of 2,791.8 n.miles was searched in the research area.
Coverage of the searching efforts of the planned cruise track line was 94.6% for the 7CN and 7CS and 67.6%
for the 7WR and 7E, respectively. In total, five large whale species including fin (4 schools / 6 individuals),
Bryde’s (125/160), common minke (12/12), humpback (2/2) and sperm (103/393) whales were sighted during
the cruise. Photo-ID images was collected from one humpback whale. Biopsy skin samples using a Larsen
system were successfully collected from fin (1) and humpback (1) whales, respectively. These data submitted
to the IWC secretary based on the SC guideline and will contribute to the work on management andconservation of large whales by the IWC SC.

KEY WORD: COMMON MINKE WHALE, BRYDE’S WHALE, SPERM WHALES, SURVEY VESSEL,NORTH PACIFICINTRODUCTION
In the western North Pacific dedicated cetacean sighting surveys based on the survey procedures of theInternational Whaling Commission/Southern Ocean Whale and Ecosystem Research (IWC/SOWER) have been
conducted since 1995 as a part of the Japanese Whale Research Program under Special Permit in the Western
North Pacific (JARPN/JARPNII). Based on the collected data the distribution patterns of large whales such as
blue, fin, sei, Bryde’s, common minke, humpback, North Pacific right and sperm whales, and abundance
estimates of common minke, sei and Bryde’s whales were investigated and reported to the IWC SC (IWC, 2001,
2010, 2016, Pastene et al., 2009, Hakamada et al., 2009, Matsuoka et al., 2016, Murase et al., 2009). The
National Research Institute of Far Seas Fisheries (NRIFSF) has also conducted dedicated sighting survey forcetaceans in the North Pacific since the 1980s (Buckland et al., 1992; Miyashita et al., 1995., Miyashita andKato, 2004; 2005, Shimada, 2004, Kanaji, 2012). In 2016 the Government of Japan planned to continue thesighting surveys in the North Pacific. The collection of sighting data to estimate abundance andbiopsy/photo-identification data to examine stock structure have been contributed to the work on management
and conservation of large whales by the IWC SC (IWC, 2010, 2016a). This paper reports the result of theJapanese dedicated sighting surveys conducted during mainly July to August in 2016. The plan for this survey
had been presented to the 2016 IWC/SC meeting (Hakamada et al., 2016) and endorsed by the SC (IWC,
2016b).
MATERIALS AND METHODS
The surveys were conducted in 2016 in the part of the western North Pacific by the research vessel Yushin-Maru(YS1) and Yushin-Maru No.2 (YS2). The vessels were equipped with a top barrel platform (TOP) and upper
bridge. Specifications of these vessels are shown in Appendix A.
Research area and period
The research area was set between 35° N and 43° N and between 140° E and 150° E (sub-areas 7CN, 7CS, 7WR
and 7E for common minke whale, see Figure 1), during 29 July to 6 September (Table 1).

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Track line design
The Survey blocks and pre-determined track lines are shown in Table 2 and Figure 1. The start point of the tracklines are decided at random using the “Distance program (ver.6.2)” and the number of the line (width in thelongitude) is decided by the research schedule based on the IWC survey guideline (IWC, 2012).
Sighting procedure
Passing mode with abeam closing was used, which followed the protocol endorsed for the IWC/SOWER cruise(IWC, 2008). There were two primary observers in the top barrel (TOP) and the upper bridge (captain andhelmsman), respectively. On the TOP, two observers conducted searching for cetaceans by using scaled
binoculars (7x). On the upper bridge, two primary observers also searched for cetaceans and recorded sighting
information. The survey was conducted 12 hours per day from 6:00 a.m. to 6:00 p.m. basically when the weather
conditions were suitable for observations: visibility better than 2.0 n.miles and wind speed less than 21 knots.
The vessel searching speed was planned to be 11.5 knots with slight adjustment to avoid vibration of vessel.
Research personnel
One researcher was on board of each research vessel. The researchers had considerable experience on whale linetransect surveys in the North Pacific and Antarctic as well as experience conducting photo-ID and biopsy
experiments through participation in the IWC/IDCR-SOWER and JARPN II Programs.
Yushin-Maru (YS1)
Ryuichiro Moriyama (Japan) – sighting data, photo-ID, biopsy

Yushin-Maru No.2 (YS2)
Hiroya Mure (Japan)– sighting data, photo-ID, biopsy

Experiments
Distance and angle experiments were conducted earlier in the Surveys. The experiment to evaluate measurement
error was conducted late in the survey following the protocol of the IWC/SOWER cruise (IWC, 2008). Whenlarge cetaceans such as blue, humpback and North Pacific right whales were found, photo-id experiments wereconducted. Further, biopsy skin sampling using Larsen system, when blue, fin, sei, humpback, North Pacificright and sperm whales were sighted.

RESULTS AND DISCUSSION
Brief narrative of the Surveys
Research vessels (YS1 and YS2) departed from Tokyo, Japan on 29 July and started the survey in the researcharea on 30 July for YS1 and 31 July for YS2, respectively (Table 1). The YS1 surveyed in the western stratum
and YS2 surveyed in the eastern stratum. They surveyed on the pre-determined trackline from north to the southin each stratum (Tables 2a and 2b, Figure 1). The vessels left the research area on 30 May and arrived at Tokyoon 6 June.
Searching effort
A summary of the period covered and sighting effort in each Survey block is shown in Table 3. A total of
1,406.2 n.miles (planned cruise track was 1,486.5 n.miles, 94.6 % searching effort coverage) in the sub-areas
7CN and 7CS, and 1,385.6 n.miles (planned cruise track was 2,049.3 n.miles, 67.6% covered) in the sub-areas
7WR and 7E were searched, respectively. A total of 2,791.8 n.miles were searched in the whole research area.
Sightings
Sightings made are summarized by the whole research period (Table 4) and sighting location of each species in
the research area are shown in Figures 2a to 2e.
Estimated Angle and Distance
The Estimated Angle and Distance Training Exercise were conducted early in the Surveys. During the exercise
the observers familiarized themselves with distance estimates from the TOP and Upper Bridge. The EstimatedAngle and Distance Experiment were conducted on 25 August by YS1. Due to a succession of low atmosphericpressures, including large typhoons in the offshore area, YS2 could not conduct this experiment during thecruise.
Fin Whale
A total of 4 schools (6 individuals) of this species were sighted in the research area (Figure 2a). Observed mean2

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school size was 1.50 (n=4). Range of the estimated body length confirmed was 15.2 – 22.8 meters. Range of thesea temperature of the sighting position was 20.9°C – 26.4°C.
Bryde’s Whale
Bryde’s whales were the most frequently species of baleen whale sighted and were widely distributed in thewhole research area (Figure 2b). A total of 125 schools (160 individuals) were observed in the research area. A
total of 20 schools (31 individuals) including 6 mother and calf pairs were observed in the coastal sub-area (7CN
and 7CS), and of 86 schools (106 individuals) including 12 mother and calf pairs were observed in the offshore
sub-areas 7WE and 7E (Table 4). Observed mean school size was 1.24 (n=182). Range of the estimated bodylength was 8.8 – 13.6 meters except calves. Range of the sea temperature of the sighting position was 19.4°C –27.0°C. Bryde’s whales are widely distributed in summer in the western North Pacific north of 35ºN based on
the recent JARPNII dedicated sighting surveys and JARPN/JARPN II catches (Shimada, 2004; Pastene et al.,2009; Hakamada et al., 2017).
Common minke whale
Common minke whales were mainly sighted (11 schools and 11 individuals) in the coastal sub-areas (Figure 2c).
No mother and calf pair was observed. Range of the estimated body length was 5.2-8.2 meters. Range of the sea
temperature of the sighting position was 18.1°C – 19.2°C. In general, common minke whales were tended to
distribute in the coastal area as surveyed in 2012 (Matsuoka et al., 2012).
Sperm Whale
Sperm whales were the most frequently sighted toothed whales in the whole research area (Tables 4 and Figure2e). A total of 103 schools (393 individuals, at least one mother and calf pairs) were observed during the Survey.
Observed mean school size was 3.82 (n=103). Because of limited approaching to the schools, there was little
information for body length and calves. Range of the sea temperature of the sighting position was 18.7°C –27.7°C.
Experiments
Photo-ID experiments
Photographs were taken from 1 humpback whale by YS2 (Table 5). All photographs were stored at the ICR
catalogue such as North Pacific right whale database (Matsuoka et al., 2014) and will be used for investigating
their stock structure in the future.
BiopsyAll of the biopsy attempts were made using the Larsen system (Larsen, 1998). Allocation of research time tobiopsy attempts was initially restricted with the aim of maximizing the searching effort to cover the research area.
A total of 2 biopsy samples were collected from 1 fin and 1 humpback whale individuals (Tables 6a and 6b). All
samples were stored at the ICR laboratory and will be used for investigating their stock structure in the future.
Report of the IWC oversight and data submission to the IWC
Detailed report of the IWC oversight was shown in Appendix B. All equipment and the survey method were thesame as in the past sighting surveys. The design of the survey blocks and track lines was improved to cover eachsurvey block based on the IWC guidelines. The planned sighting procedure was in accordance with theguidelines agreed by the SC (IWC, 2012). Objectives and procedure of the survey were explained to the captains,
officers, crew and researcher in advance. Sighting data was sent to the IWC secretary and confirmed on 8 April
2017.

ACKNOWLEDGEMENT
We acknowledge the Government of Japan’s assistance in providing the research permits and funding for thiscruise. We also thank the officers and crew of the Yushin-Maru and Yushin-Maru No.2 for their hard work anddedication that led to the successful execution of this cruise. We thank Drs. Seiji Ohsumi, Yoshihiro Fujise, Luis
Pastene, Tsutomu Tamura and the staff of the Institute of Cetacean Research (Tokyo) and Kyodo Senpaku Co.
Ltd. for their assistance in arrangements and support for the cruise. We thank to Dan Goodman for his
suggestions to improve the draft of this paper.

REFERENCES
Buckland, S.T., Cattanach, K.L. and Miyashita, T. 1992. Minke whale abundance in the northwest Pacific and3

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the Okhotsk Sea, estimated from 1989 and 1990 sighting surveys. Rep. int. Whal. Comn 42: 387-92.
Hakamada, T., Matsuoka, K. and Miyashita, T., 2009. Distribution and the number of western North Pacificcommon minke, Bryde's, sei and sperm whales distributed in JARPNII Offshore component survey area.
SC/J09/JR15. 18pp. [Paper available at the IWC Office].
Hakamada, T., Matsuoka, K. and Miyashita, T., 2016. Research plan for a cetacean sighting surveys in theWestern North Pacific in 2016. SC/66b/IA07. 5pp. [Paper available at the IWC Office].
Hakamada, T., Takahashi, M., Matsuoka, K. and Miyashita, T., 2017. Abundance estimate for western North
Pacific Bryde’s whale by sub-areas based on IWC-POWER and JARPNII sighting surveys.
SC/M17/RMP2. 11pp. [Paper available at the IWC Office].
IWC, 2001. Report of the Workshop to Review the Japanese Whale Research Program under special permit for
North Pacific minke whales (JARPN). J. Cetacean Res. Manage. 3 (Supp.):377-413.
IWC,
2008.
IWC
SOWER
Cruise2008/09,
InformationforResearchers.
http://iwcoffice.org/_documents/sci_com/SOWER/Guide%20%20for%20Researchers%202008-09.pdf
IWC, 2010. The Report of the Expert Workshop to review the ongoing JARPN II Programme. J. Cetacean Res.
Manage. 11 (Supp.2):405-450.
IWC. 2012. Requirements and Guidelines for Conducting Surveys and Analyzing Data within the Revised
Management Scheme. J. Cetacean Res. Manage. 13 (Supp.):507-18.I
IWC, 2016a. The Report of the Expert Workshop to review the ongoing JARPN II Programme. J. Cetacean Res.
Manage. XX (Supp.X):xxx-xxx.

IWC. 2016b. Report of the Scientific Committee. Annex G. 23pp. San Diego, USA, 2015. [Paper available
at the IWC Office].
Kanaji, Y., Iwasaki, T., Kishiro, T. and Miyashita, T., 2012. Cruise report of the sighting and satellite tagging
survey for common minke whales in the sub-area 7 in 2011. SC/64/O9. 10pp. [Paper available at the IWC
Office].
Larsen, F., 1998. Development of a biopsy system primarily for use on large cetaceans. SC/50/O15. 8pp. [Paper
available at the IWC Office].
Matsuoka, K., Hakamada, T. and Miyashita, T., 2016. Distribution of blue (Balaenoptera musculus), fin (B.
physalus), humpback (Megaptera novaeangliae) and north pacific right (Eubalaena japonica) whales in
the western North Pacific based on JARPN and JARPN II sighting surveys (1994 to 2014). SC/J09/JR35.
12pp. The IWC/SC JARPNII review meeting, Yokohama, 26-30, January. [Paper available at the IWC
Office].
Matsuoka, K., Hakamada, T. and Miyashita, T., 2014. Recent sightings of the North Pacific Right (Eubalaena
japonica) whales in the western North Pacific based on JARPN and JARPN II surveys (1994 to 2013).
SC/65b/BRG11. 8pp. [Paper available at the IWC Office].
Miyashita, T., Kato, H. and Kasuya, T., 1995. Worldwide Map of Cetacean Distribution based on Japanese
Sighting Data (Volume 1). pp43-56.
Miyashita, T. and Kato H. 2004. Plan for the North Pacific minke whale sighting surveys in 2004. SC/56/RMP3.
3pp. [Paper available at the IWC Office].
Miyashita, T. and Kato H. 2005. Plan for the minke whale sighting surveys in the North Pacific in 2005.
SC/57/NPM2. 5pp. [Paper available at the IWC Office].
Murase, H., Hakamada, T., Kiwada, H., Inagake, D., Okazaki, M., Tojyo, N. and Matsuoka, K., 2009.
Preliminary results of estimation of sei whale (Balaenoptera borealis) distributuion and abudnace in thewhole North Pacific basin. Appendix 2. 11pp. In: Hakamada, T., Examination of the effects on whale
stocks of future JARPN II catches. SC/J09/JR36. 56pp.
Pastene, L,A., Hatanaka, H., Fujise, Y., Kanda, N., Murase, H., Tamura, T., Miyashita, T. and Kato, H., 2009.
The Japanese Whale Research Program under Special Permit in the western North Pacific Phase-II(JARPN II): origin, objectives and research progress made in the period 2002-2007, including scientificconsiderations for the next research period. SC/J09/JR1 (Rev 1). 73pp.
Shimada, 2004. Abundance estimate of the western North Pacific stock of Bryde’s whales using sighting datafrom 1998 to 2002. SC/56/PIF6. 8pp.

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Table 1. Cruise itinerary of this survey.
Date

Event

29-July-2016

Vessels departed Tokyo, Japan

30-July-2016

YS1 arrived at the starting point in the research area (coastal area)

31-July-2016

YS2 arrived at the starting point in the research area (offshore area)

2-September-2016

YS2 completed the research at 35º00’N (33 days in the research area)

3-September-2016

YS1 completed the research at 35º00’N (35 days in the research area)

6-September-2016

Vessels arrived Shimonoseki, Japan

Table 2a. Waypoint (WP) in the research area 7CN and 7CS surveyed by YS1.
7CN

WP

Lat.

101

42

-

Long.

25.0

N

146

-

7CS WP

11.0

Lat.

Long.

E

131

41

-

00.0

N

142

-

27.6

E

102

42

-

21.0

N

146

-

04.8

E

132

40

-

39.0

N

141

-

35.0

E

103

43

-

02.0

N

145

-

31.2

E

133

40

-

06.3

N

143

-

13.4

E

104

41

-

54.9

N

145

-

04.9

E

134

39

-

33.2

N

142

-

12.0

E

105

42

-

50.0

N

144

-

36.2

E

135

39

-

00.4

N

142

-

59.8

E

106

41

-

29.2

N

144

-

06.3

E

136

38

-

38.2

N

141

-

37.0

E

107

42

-

30.0

N

143

-

36.2

E

137

38

-

15.0

N

141

-

13.0

E

108

41

-

03.3

N

143

-

07.7

E

138

37

-

53.5

N

142

-

42.8

E

109

42

-

03.0

N

142

-

39.6

E

139

37

-

19.3

N

141

-

05.0

E

110

40

-

59.9

N

142

-

09.1

E

140

36

-

45.5

N

142

-

25.9

E

111

42

-

30.0

N

141

-

39.6

E

141

36

-

10.1

N

140

-

40.0

E

112

42

-

00.5

N

141

-

28.3

E

142

35

-

36.4

N

142

-

09.0

E

143

35

-

00.0

N

140

-

05.0

E

Table 2b. Waypoint (WP) in the research area 7WR and 7E surveyed by YS2.
7WR

WP
201

Lat.
42

-

00.5

Long.
N

145

-

7E

17.7

WP

Lat.

E

231

35
35

-

Long.
N

147

56.7

E

-

00.0

E

-

00.0

E

147

-

00.0

E

N

150

-

00.0

E

00.0

E

00.0
06.8

E

202

40

-

53.5

N

147

-

00.0

E

232

-

00.0
20.2

N

147

203

39

-

45.7

N

143

-

11.4

E

233

36

-

24.2

N

150

204

38

-

35.9

N

147

-

00.0

E

234

37

-

27.3

N

38

-

29.6

-

205

37

-

25.6

N

142

-

35.9

E

235

206

36
35

-

13.8
01.0

N

-

00.0
00.4

E
E

39

N

147

237

40

-

30.9

N

147
142

236

207

31.4

N

150

-

208

35

-

N

142

-

05.0

E

238

40

-

49.1

N

149

-

00.0

Table 3. Summary of the survey periods and searching effort (n.miles).
Research
vessels
Coastal(7CN+7CS)(YS1)Offshore(7WR+7E)
(YS2)
Total

Cruise period(y/m/d)Research area
periodPlanned cruise
track (n.miles)

Searchingeffort (n.miles)

Coverage ofeffort (n.miles)

2016/7/29-9/6

2016/7/30- 9/3

1,486.5

1,406.2

94.6%

2016/7/29-9/6

2016/7/31- 9/2

2,049.3

1,385.6

67.6%

2016/7/29-9/6

2016/7/30- 9/3

3,535.8

2,791.8

79.0%

5

E

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Table 4. Number of sightings by species and stratum in the research area including transit survey between port
and the research area.
Transit to
R.A.
sch.
Ind.

Coastal(7CN+7CS)
sch.
Ind.

Offshore(7WR+7E)
sch.
Ind.

Transit from
R.A.
sch.
Ind.

sch.

Ind.

Fin whale

0

0

1

1

3

5

0

0

4

6

Bryde's whale

19

23

20

31

86

106

0

0

125

160

Common minke whale

0

0

11

11

1

1

0

0

12

12

Humpback whale

0

0

0

0

2

2

0

0

2

2

Sperm whale

21

124

33

87

49

182

0

0

103

393

Unid. Large whale

24

27

7

7

9

9

0

0

40

43

Species

Total

Table 5. Number of photo-ID individuals photographed, by each stratum.
Coastal(7CN+7CS)(YS1)
0Photo-ID
Humpback whale

Offshore(7WR+7E)
(YS2)
1

Total
1

Table 6a. Number of biopsy samples collected, by each stratum.
BiopsyFin whale

Coastal(7CN+7CS)(YS1)
1Offshore(7WR+7E)
(YS2)
0

0

1

Humpback whale

Total
1
1

Table 6b. Number of biopsy samples collected, by each stratum. Including one mother and calf pair in theSouthern strata.
Vesl.

Sheet

Dat e

number

Sight

Sp.

No.

Scl.

Sighted Posit ion

Area

size

Lat.

[min.] Long. [min.]Start time

End time

ExperimentEst. body length

numbernumberPosition

numberSampleShooting

of BX

of BX

durationof target ind. [m]of shootof hitstruckof sample

No.

equipment

Notes.

YS1

BY140

20160901

1

F

1

35

43.05

141

51.64

7

8:01:22

8:30:1500:28:53

15.2

5

1

RC1

1

J16NYS1F02

Larsen

-

YS2

BY234

20160807

17

H

1

38

33.19

146

49.93

7

11:48:12

12:12:48

00:24:36

7.3

2

1

LB1a

1

J16NYS2H04

Larsen

-

YS2

BY235

20160901

13

F

1

40

15.30

149

11.64

7

14:36:12

15:01:15

00:25:03

22.4

0

0

-

0

-

Larsen-6

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Figure 1. The 2016 research area and pre-determined track lines with their waypoint (WP) number (7CN:
101-112, 7CS: 131-143, 7WR: 201-208, 7E: 231-238). Survey order followed a WP number insequence.

Figure 2a. Sighting locations of fin whales in the research area.

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Figure 2b. Sighting locations of Bryde’s whales in the research area.

Figure 2c. Sighting locations of common minke whales in the research area.

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Figure 2d. Sighting locations of Humpback whale in the research area.

Figure 2e. Sighting locations of sperm whales in the research area.

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APPENDIX A.

SHIP SPECIFICATIONS AND CREW LIST OF YUSHIN-MARU ANDYUSHIN-MARU NO.2.

Ship photo:

Ship specifications:
Call sign
Length overall [m]Gross tonnage (GT)TOP barrel height [m]IO barrel height [m]Upper bridge height [m]Bow height [m]Engine power [PS / kW]

Yushin-Maru
JLZS
69.61
724
19.5
13.5
11.5
6.5
5280 / 3900

Researcher
Captain
Chief Officer
Second Officer
Junior Second Officer
Chief Engineer
First Engineer
Second Engineer
Third Engineer
Chief Operator
Second Operator
Boatswain
Quartermaster
Quartermaster
Quartermaster
Quartermaster
Sailor
SailorWiper
Chief Steward
Steward

Yushin-Maru
Ryuichiro Moriyama
Nobuo Abe
Motonori Aki
Chikara Omukai
Seiichiro Teruya
Hiroyuki Hagiwara
Shigeki Miyamoto
Kenji Kawamoto
Hiroyuki Nabekura
Kenji Tsuda
Hisaji Suzuki
Kenji Wakatsuki
Hisashi Katase
Takato Sawabe
Hayata Nawa
Shinya Torihara
Takumi Kondo
Akihiko Toyomura
Kento Baba

Yushin-Maru No.2
JPPV
69.61
747
19.5
13.5
11.5
6.5
5280 / 3900

Crew list:

10

Yushin-Maru No.2
Hiroya Mure
Chikamasa Okoshi
Tomoya Hirai
Masahiro Yamazaki
Akihide Oide
Ryuta Miyamoto
Koji Takamatsu
Takashi Matsubara
Jun Kuwaoka
Masahiko Abe
Kazuyuki Sugiyama
Kosuke Maehashi
Takahiro Nagai
Takashi Kominami
Naoto Suzuki
Toshikazu Takahashi
Yuji Isotani
Seichi Hamashita
Masanobu Abe

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Appendix B. Oversight for the 2016 Japanese dedicated sighting survey in the western North PacificKoji Matsuoka
Institute of Cetacean Research
4-5, Toyomi, Chuo, Tokyo, 104-0055, JAPANThe plan of this survey was presented to the 2016 IWC/SC meeting (Hakamada et al., 2016) and endorsedby the Scientific Committee (IWC, 2016). On behalf of the IWC Scientific Committee I carried out theoversight work during the 2016 Japanese dedicated sighting survey in the western North Pacific. This is abrief report of the oversight activities conducted on that survey.
Preparatory work
The pre-cruise meeting carried out at Shimonoseki on 22 April 2016. The survey organizers, researchersand crewmembers also participated in that meeting. During the meeting the organizers explained theobjective of the survey and the procedure to be used for both sightings and experiments. The plannedsighting procedure was in order with that agreed by the Scientific Committee. The research vessels
Yushin-Maru and Yushin-Maru No.2 were engaged for this survey.
The research area was set between 35° N and 43° N and between 140° E and 150° E. The survey was
conducted between 29 July and 6 September. The vessels were assigned to cover pre-determined transects
in these areas by the passing with abeam closing mode (NSP). Two experienced researchers were assigned
to work on board each vessel.
Oversight method and period
The research activities of the vessels were oversight by e-mail communication and by examining the daily
report prepared by each researchers on board. In some instances Inmarsat satellite telephone calls weremade for further clarification of the activities, procedure and sightings made. Further, geographicalpositions and weather information of each vessel were tracked each other per day. Over sight activity werecarried between 29 July and 6 September.
Brief narrative of the oversight vessel
Research vessels (YS1 and YS2) departed from Shimonoseki, Japan on 29 July and started the survey in the
research area on 30 July. The YS1 surveyed in the sub-areas 7CN and 7CS, and YS2 surveyed in the sub-areas
7WR and 7E. The vessels left the research area and arrived at Shimonoseki on 6 September.

Post-cruise meeting
I participated in a post-cruise meeting held on 6-7 September 2016 at Shimonoseki. Survey organizers,
researchers and the Captain participated in that meeting. Apart to discuss and assess the results of thesurveys, the researchers engaged in the verification and checking of data.
Conclusion
All equipment and the survey method of each vessel were the same as in the past sighting surveys. The
design of the survey strata and track lines were improved to cover each strata completely. The plannedsighting procedure was in accordance with the guideline agreed by the SC (IWC, 2012). Objectives andprocedure of the survey were explained to the captains, officers, crew and researcher in advance. I thenendorse the information and data obtained during the 2016 Japanese dedicated sighting survey in thewestern North Pacific.
Reference
IWC. 2012. Requirements and Guidelines for Conducting Surveys and Analysing Data within the Revised
Management Scheme. J. Cetacean Res. Manage. (Suppl2.) 11:507-18.
IWC. 2016. Report of the Scientific Committee. Annex G. 23pp. Bled, Slovenia, 2016. [Paper available atthe IWC Office].
Hakamada, T., Matsuoka, K. and Miyashita, T., 2016. Research plan for a cetacean sighting surveys in theWestern North Pacific in 2016. SC/66b/IA07. 5pp. [Paper available at the IWC Office].

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