This paper can not be cited without written permission from the authors
SC/61/O7

Movement of Bryde's whales in the western North Pacific as
revealed by satellite tracking experiments conducted under
JARPN IISHIGETOSHI NISHIWAKI, SEIJI OTANI AND TSUTOMU TAMURAThe Institute of Cetacean Research, 4-5 Toyomi-cho, Chuo-ku, Tokyo, 104-0055, Japan
Contact e-mail: nisiwaki@cetacean.jp
ABSTRACT
Using an air gun system (ICR air gun) a satellite tag was successfully attached on one Bryde’s whales in the western North
Pacific during the research conducted by JARPN II in each 2006 and 2008. The movement of these two whales were tracked
for a period of 15 and 21 days, respectively. In general, movement in both cases was from temperate to subtropical waters. In
2006, an Argos transmitter was attached at position 37º 36.54’N; 156º10.44’E on 13 July. The whale had an estimated bodylength of 12.5m and was accompanied by a calf (estimated body length of 8.7m).The distance of movement during thetransmission was approximately 1,024.53km and the daily average movement distance was 77.13km. The whale showed amovement from north to south. In 2008, an Argos transmitter was attached in position 37º56.64’N; 147º51.72’E on 24 July.
The whale had an estimated body length of 12.6m. The distance of movement during the transmission was approximately
2,629.70km and the daily average movement distance was 127.14km. This whale moved first in easterly direction for the firstnine days reaching 160ºE after which it moved in a southerly direction, for the last 12 days of transmission. These results
demonstrated that the ICR system for delivering satellite tags is useful for fast swimming whales in pelagic waters. Information
on movement and residence time in the feeding grounds will be useful to assist the stock structure studies of Bryde’s whales inthis ocean basin, which is an important piece of information for the RMP’s Implementation Simulation Trials (ISTs).

KEYWORDS: BRYDE’S WHALE, NORTH PACIFIC; SCIENTIFIC PERMIT; SATELLITE TAG

INTRODUCTION
Satellite tagging using a crossbow system has been successfully carried out on several cetacean species in coastal waters (Mateet al. 2007). In pelagic waters, only large vessels can be used and the target species are usually fast swimming whales. Suchwhale species are usually chased at high speed and it is not possible for a weak powered-crossbow system to fire and attach thetag under condition of high ship speed and strong wind. Since the late 1980’s the Institute of Cetacean Research (ICR), withthe cooperation of the Miroku Machinery Co.Ltd., developed an air gun with the original objective of biopsy skin sampling.
This is called the “ICR gun” (Nishiwaki et al., 1990; Kasamatsu et.al 1991). The ICR gun has been used to collect a substantial
number of biopsy samples from large whales in both the Antarctic (under JARPA/JARPA II) and western North Pacific (underJARPN.JARPN II).
More recently the ICR gun has been improved to attach satellite tags on fast swimming whales in pelagic waters. At this stage
experiments on satellite tagging under JARPA/JARPA II and JARPN/JARPN II are conducted as a medium-priority activity(the time for the trial is limited to 60 minutes or less in principle). Satellite tagging experiments could provide important
information on distribution and movement of whales. Particularly it could provide information of movement of whales within
the feeding grounds as well movement between feeding and breeding grounds. Such information could assist the studies onstock structure of large whales based on genetics and other non-genetics approaches.
This study provides technical information of the tagging system used by the ICR and reports results of two successfully
deployed tags on western North Pacific Bryde’s whales, under the JARPN II.

1

MATERIALS AND METHODSICR gunFigure 1 show the ICR gun, which is used for satellite tagging. This gun is a modified version of the original Miroku Lineshooter M-63 designed for life saving in case of fire and ship wrecks (developed by Miroku Machinery Co.Ltd). The calibre
was modified from 63mm to 40mm and the barrel is made of stainless steel instead of the original iron. The length of the gun is
100cm and that of the barrel is 60cm. The weight is 5kg. The initial shooting speed of the satellite tag with a 3mm nylon ropeis 70m-86m/sec at the filling pressure of 100-150kgf/cm2. The maximum shooting range is 80-100m with angle of 15 degreefrom the horizon. Firings are made from the forecastle deck which is 6.5m above the sea surface. The effective firing distanceis less than 30m at vessel speeds of 12-15knots.
Satellite tagging darts
The satellite tagging dart system was designed for installation on the ICR gun (Figure 2). The 3mm nylon rope is folded andaccommodated in the storage compartment to avoid interference with the trajectory of the dart. The dart system was composedof three parts: the dart, an Argos transmitter and a retrieve cylinder. When the whale is hit, the dart becomes embedded in theblubber and muscle. And the Argos transmitter is fixed at the surface of the body. The retrieve cylinder with the nylon rope isdislodged by the swimming of the whale.
RESULTS AND DISCUSSION
Summary of the JARPN II satellite tagging on Bryde’s whales
Table 1 shows a summary of the satellite tagging experiments on Bryde’s whales under JARPN II for the period 2004 - 2008.
A total of nineteen schools (21 individual whales) were approached for satellite tagging. The total experiment time was 632
minutes. Fifteen of these schools were approached within the optimum firing range of the equipment (30m or less). 18 shots
were made within this range. There were 7 hits and 2 ricochets and 9 misses. Through these trials in 6 of the 7hits Argos
transmitters were fixed to the body of the whale. Others failed because the shooting impact caused the rope to break and thetransmitter to fault.
Vertical fixation of the antenna related to the surface of the sea is important to get a valid transmission performance. If the tag
is attached on the back of the body Argos transmissions are effective (there are two example cases in the experiments underJARPN II where the antenna was fixed on the front back of the body near the dorsal fin; Figure 3). The angle of the fixed
antenna in relation to the surface determines the effectiveness of the transmissions.

Movement of tagged Bryde’s whales
In the case of two Bryde’s whales the antenna was fixed and transmission obtained for period of 15and 21 days respectively(Table 1). In both cases movement from the temperate area toward the subtropical area in the north-west Pacific Ocean in thesummer season was observed.
In 2006, an Argos transmitter was attached (15-days transmission) (Table 2) at position 37º 36.54’N; 156º10.44’E on 13 July.
The chasing time before firing was eight minutes. The firing distance was 10 meters. The whale had an estimated body lengthof 12.5m and was accompanied by a calf (estimated body length of 8.7m).The distance of movement during the transmission
was approximately 1,024.53km and the daily average movement was 77.13km. The whale moved from north to south (Figure4).
In 2008, an Argos transmitter was attached (21-days transmission) (Table 3) at position 37º56.64’N; 147º51.72’E on 24 July.
The chasing time before firing was four minutes. The firing distance was 20 meters. The whale had an estimated body lengthof 12.6m. The distance of movement during the transmission was approximately 2,629.70km and the daily average movement
was 127.14km. This whale moved first in easterly direction for the first nine days reaching 160ºE after which it moved in asoutherly direction for the last 12 days of transmission (Figure 4).
These results demonstrated that the ICR system for delivering satellite tags is useful for fast swimming whales in pelagicwaters. Information on seasonal movements, and residence time in the feeding grounds will be further accumulated if the effort
on these experiments is increased. This information will be useful to assist the stock structure studies of Bryde’s whales in thisocean basin, which is an important piece of information for the RMP’s Implementation Simulation Trials (ISTs). Experiments
will be attempted on other baleen whale species in the future.
ACKNOWLEDGEMENTS
We would like to thank all captains, crews and researchers who were involved of the offshore component of JARPN II surveys
from 2000 to 2007. Our sincere thank to H. Hatanaka and L.A. Pastene of the Institute of Cetacean Research (ICR) for theirvaluable suggestions and useful comments on this paper.

2REFERENCES
Kasamatsu, F., Iwata, S., and Nishiwaki, S. 1991. Development of biopsy skin sampling system for fast swimming whales inpelagic waters. Rep. Int. Whal. Commn 41:555-7.
Mate, B., Mesecar, R., and Lagerquist, B. 2007. The evolution of satellite-monitored radio tags for large whales: Onelaboratory’s experience. DEEP-SEA RESEARCH Part II.54. 224-247.
Nishiwaki, S., Joyce, G., Enser, P., Mermoz, J., Sanpera, C. amd Kasamatsu, F. 1990. Report on the Biopsy Dart Samplingfeasibility study during the 12th IWC/IDCR Southern Hemishere Minke Whale Assessment Cruise, 1989/90. Paper
SC42/SHMi21 presented to the IWC Scientific Committee, May 1990 (unpublished).

Table 1 Summary of the satellite tagging experiments for Bryde’s whales during JARPN II surveys.
VesselDate
20040913

Sight
No.
1Scl.
size
1

YS1
YS2
YS2
YS1

20040913
20040913
20060713

34111
11

YS2
YS2
YS2
YS2
YS2
YS2
YS2YS2

20060713
20060713
20080715
20080715
20080723
20080723
20080724
20080726

5
7
5
64
6
4
4

1
2
1
1
1
1
1
1

YS1
YS1
YS1
YS1
YS1
YS1
YS1

20080722
20080722
20080723
20080723
20080723
20080724
20080726

3
5
6
78
7
10

1
1
1
1
1
1
2

Est.body length Trial durationChase durationFiring dist. Verdicts Positionof target ind.(m)
(h:m)
(h:m)
(m)
struck
13.5
00:40
00:09
27
Miss
00:14
27
Hit
LE1
10.8
00:09
00:09
10Hit
LB1P
11.2
00:09
00:09
15Ricochet
LB1P
11.0
00:46
00:23
20
Miss00:23
18
Miss00:31
00:31
10Miss
9.5
12.5
00:08
00:08
10
Hit
RC100:51
13.3
12.8
00:32
12.5
00:24
00:24
25
Miss
11.7
00:31
12.6
00:10
00:04
20
Hit
RC100:34
00:09
30
Miss
12.6
00:09
25
Hit
RC100:55
13.5
12.2
00:55
00:55
13Miss
12.2
00:44
00:44
10
Ricochet
LC2
13.2
00:31
00:31
9Miss
11.8
00:31
00:31
10
Miss
00:25
00:25
8
Hit
RC2
12.4
12.4
01:05
01:04
9Hit
LB2

3

Transmitter Electric wave
attached
received
Fix
Fix
Lost
Lost
Lost
Fix

NoNoYes

Lost
Fix

Yes

Fix

No

Lost
Fix

NoTable 2 Summary of the satellite tracking of a Bryde’s whale in the western North Pacific (15-days transmission) (2006JARPN II)

Date2006 7777777777777
77

Time
13 Attached
7:09:07
23:23:10
14
2:10:45
5:06:26
6:45:11
10:42:16
19:05:45
15
0:42:27
4:54:12
10:18:12
14:26:28
17:21:42
18:41:38
16
1:48:47
3:04:18
3:29:28
5:58:45
11:34:30
17:07:55
17
1:39:06
3:18:52
5:22:15
7:12:18
16:58:02
19:33:01
18
19:10:17
19
4:36:486:23:33
18:32:09
20
2:49:59
15:15:48
21
3:43:23
5:20:02
15:07:28
22
14:56:20
23
3:23:1724
3:10:49
25
17:05:14
26
1:47:0527
6:33:02

Location
level
00
1
102
311
120
1012
102
122
1
101
A
A
A
000
B
1
100
120

Position
LatitudeLongtuide37.609 N
156.174 E
37.541 N
156.038 E
37.176 N
155.561 E
37.182 N
155.537 E
37.038 N
155.531 E
36.961 N
155.528 E
36.780 N
155.422 E
36.591 N
155.311 E
36.458 N
155.243 E
36.551 N
155.147 E
36.617 N
154.994 E
36.617 N
154.998 E
36.599 N
154.986 E
36.603 N
155.003 E
36.586 N
154.828 E
36.599 N
154.821 E
36.580 N
154.802 E
36.596 N
154.829 E
36.456 N
154.893 E
36.366 N
154.705 E
36.180 N
154.589 E
36.186 N
154.543 E
36.177 N
154.453 E
36.201 N
154.395 E
36.446 N
154.247 E
36.516 N
154.118 E
36.149 N
153.940 E
35.727 N
154.060 E
35.611 N
153.826 E
35.132 N
153.737 E
34.734 N
153.429 E
34.331 N
153.156 E
34.044 N
153.200 E
34.010 N
153.260 E
33.872 N
153.237 E
33.450 N
153.370 E
33.338 N
153.444 E
33.127 N
153.766 E
32.055 N
153.873 E
31.714 N
153.758 E
30.863 N
153.406 E

4

Trackking dist.(Km)
Daily
Cumulative
14.16
58.43
2.23
15.96
8.53
22.16
23.16
15.94
13.41
15.50
0.36
2.26
1.58
15.74
1.57
2.70
2.99
16.53
19.56
23.08
4.18
8.14
5.85
30.21
13.88
43.64
47.97
24.74
53.66
52.26
51.16
32.04
6.69
15.43
48.32
14.18
37.99
119.09
39.27
99.96

72.60
74.82
90.79
99.32
121.48144.64160.58173.99189.49189.84
192.11
193.69209.43211.00213.71
216.70233.23252.79275.87280.06288.20294.05324.25338.14381.77429.74454.49508.15560.41611.57643.61650.30665.73714.04728.22766.21885.30924.571024.53

Table 3 Summary of the satellite tracking of a Bryde’s whale in the western North Pacific (21-days transmission) (2008
JARPN II)

Date

Time

2008 7 24 Attached
5:39:38
25
1:34:31
11:54:30
18:28:06
22:28:32
23:01:42
26
23:48:00
27
1:12:44
5:41:28
6:08:19
10:00:18
28
15:05:0429
5:17:53
5:19:17
23:20:0730
5:05:33
22:55:57
31
4:53:47
18:30:09
22:36:06
1
5:47:33
9:09:11
18:07:24
22:14:33
2
1:47:29
6:09:47
3
18:26:51
22:23:55
4
8:55:16
9:40:50
10:30:54
13:54:13
5
5:34:11
18:10:27
6
2:45:04
8:52:32
17:48:10
22:14:23
7
9:28:18
17:35:44
8
9:08:24
17:25:59
21:32:08
9
10:26:43
10
2:03:38
11
1:52:46
10:13:31
17:30:47
22:12:28
12
1:40:04
18:24:07
22:19:22
13
5:55:50
10:42:10
14:04:45
21:31:11

Location
level
0
1111
111322122112111222222222222111123321211111220002322

Position
LatitudeLongtuide
37.944 N
147.862 E
38.014 N
147.867 E
38.341 N
148.874 E
38.150 N
149.430 E
38.117 N
149.758 E
38.039 N
150.012 E
38.020 N
150.041 E
37.763 N
151.494 E
37.781 N
151.628 E
37.739 N
151.915 E
37.738 N
151.957 E
37.711 N
152.223 E
37.470 N
154.044 E
37.397 N
154.79 4 E
37.392 N
154.791 E37.218 N
155.767 E
36.925 N
156.275 E
36.290 N
157.268 E
36.141 N
157.913 E
36.201 N
158.66 8 E
36.115 N
158.996 E
35.987 N
159.582 E
35.906 N
159.800 E
35.739 N
160.035 E
35.554 N
160.214 E
35.411 N
160.349 E
35.205 N
160.520 E
34.684 N
160.682 E
34.519 N
160.660 E
34.215 N
160.851 E
34.244 N
160.896 E
34.203 N
160.857 E
34.200 N
160.921 E
33.959 N
161.358 E
33.802 N
161.782 E
33.505 N
162.196 E
33.324 N
162.598 E
33.180 N
162.860 E
32.965 N
163.032 E
32.393 N
163.039 E
32.242 N
163.124 E
31.481 N
163.398 E
31.224 N
163.561 E
30.948 N
163.664 E
30.141 N
163.974 E
29.348 N
164.294 E
27.970 N
164.701 E
27.366 N
164.703 E
26.967 N
164.757 E
26.629 N
164.840 E
26.392 N
164.870 E
25.441 N
164.702 E
25.195 N
164.688 E
24.762 N
164.548 E
24.522 N
164.585 E
24.356 N
164.652 E
24.035 N
164.773 E

5

Trackking dist.(Km)
Daily
Cumulative
7.77
95.24
52.99
28.94
23.87
3.30
130.71
11.95
25.67
3.70
23.60
162.7466.750.61
88.50
55.56
113.19
60.20
69.20
29.94
54.58
21.59
28.13
26.11
20.01
27.59
59.56
18.38
37.96
5.24
5.79
5.90
48.30
42.84
50.50
42.36
29.12
28.70
63.32
18.53
88.12
32.38
32.08
94.11
93.03
157.54
66.81
44.45
38.28
26.29
106.59
27.24
49.91
26.80
19.57
37.55

103.00156.00184.94208.80212.10342.82354.76380.43384.13407.73570.4 8637.23637.84726.34781.90895.0 9955.291024.49
1054.43
1109.01
1130.60
1158.731184.841204.85
1232.441292.00
1310.38
1348.34
1353.58
1359.36
1365.26
1413.561456.40
1506.911549.27
1578.391607.091670.41
1688.94
1777.06
1809.44
1841.53
1935.642028.66
2186.202253.01
2297.472335.752362.04
2468.632495.872545.792572.592592.152629.70

Figure 1 ICR air gun used for satellite tag experiments

Figure 2 Satellite tag dart, which is installed in the ICR air gun

6

Figure 3 The Bryde’s whale with the satellite tag attached (Red circle).
(Left: 2006 JARPN II, Right: 2008 JARPN II))

080724 22:53

060714 10:42

060726 19:19
080813 21:31

Figure 4 Satellite tracks of two Bryde’s whales in the western North Pacific (2006 and 2008 JARPN II surveys)(Left: 2006 JARPN II, Right: 2008 JARPN II)

7