homing behavior of chum salmon determined by an archival tag

NPAFC Doc.425 Rev.

Homing behavior of chum salmon determined by an archival tag

by

KeikoWada Japan NUS Co. LTD.

9-15 Kaigan 3-chomeMinato-ku, Tokyo 108-0022, Japan

and

Yasuhiro Ueno Tohoku National Fisheries Research Institute Hachinohe Branch,

Fisheries Agency of Japan,

25-259, Shimo-mekurakubo, Same-machi, Hachinohe-shi 031-0841, Japan

Submitted to the NORTH PACIFICANADROMOUS FISH COMMISSION

by JAPAN

October 1999

THIS PAPER MAY BE CITED IN THE FOLLOWING MANNER:

Wada, K. and Y. Deno. 1999. Homing behavior of chum salmon determined by an archival

tag. (NPAFC Doc.425). Hokkaido National Fisheries Research Institute. 116 Katsurakoi,

Kushiro, Hokkaido, 085-0802, Japan. 29p.

Homing behavior of chum salmon determined by an archival tag

Keiko Wada Japan NUS Co. LTD.

9-15 Kaigan 3-chome Minato-ku, Tokyo 108-0022, Japan

and

Yasuhiro Ueno Tohoku National Fisheries Research Institute Hachinohe Branch,

Fisheries Agency of Japan,

25-259, Shimo-mekurakubo, Same-machi, Hachinohe-shi 031-0841, Japan

Abstract

In order to investigate homing behavior of mature chum salmon, Oncorhynchus keta ,

we tagged 25 chum salmon using NMT archival tags and released them in the central part of

the Bering Sea in the summer of 1998. Three fish tagged were recovered in the eastern coast

of Hokkaido in the autumn ofthe same year. We could take the complete data series on light,

water pressure, inner and outer temperatures of the fish body from the archival tags

recovered. Daily locations of the fish were estimated based on light data and outer

temperatures (sea surface temperature). Migration routes determined by connections ofthe

daily location suggest that the fish roughly took the shortest course between the release and

recovery sites. Vertical movement of the fish was determined by the data on water pressures.

We found four behavior patterns of the fish as following.

1) Pattern-A: Staying in the surface waters and in the vicinity of the release sites in the

period immediately following tagging (6-15 days):

2) Pattern-B: Frequently repeating to dive into mid-waters and rise to surface waters at

daytime (the up-and down behavior) and staying in surface waters at nighttime,

migrating long distance from waters near the release sites (Bering Sea) to near the

ridges of continental shelf of Hokkaido (47-77 days).

3) Pattern-C: Continuously submerging in deep layers (160-270m) during about 1 day at

the ridges of continental shelf of Hokkaido (1 day).

4) Pattern-D: Decreasing frequency ofthe up-and-down behavior at daytime and increasing

a tendency to stay in surface waters through day and night, migrating in the coastal

waters (2-6 days).

1

Pattern-A can be interpreted as the period taken to recuperate the trauma of the

tagging. Very frequent up-and-down behaviors in Pattern-B often corresponded to solar

altitude and it suggests that this behavior might be related to location and orientation for

homing. Pattern-C probably indicates a specific behavior process required to be adapted for

preparation in maturation and orientation in coastal waters. Pattern-D suggests that chum

salmon changed navigation system from for the offshore waters (light using system) to for the

coastal waters (olfactory sense using system).

Introduction To elucidate migration routes of salmon (Oncorhynchus spp.), many tag-recovery

experiments had been conducted (for example, Ogura, 1995). No information on behaviors

on the way between the release and recovery sites was gathered, although normal tagging

experiments (for example, dart type or disk type tag) provided much information on salmon

migration. In recent years, some experiments using an ultrasonic transmitter and an

archival tag with the temperature and depth sensors has come to be used for salmon

migration study (for example, Ogura and Ishida. 1995; Walker et aI., 1999). Studies on the

ultrasonic transmitter gave some precious information on salmon swimming behaviors.

However, the time for tracking the transmitter was limited within few days, because it

requires tracking by a vessel. Recent studies on the archival tag clarified temperature and

depth history on salmon migration. Walker et al. (1999) used an archival tag with

temperature sensors for tagging experiments in offshore waters and got some recoveries in

coastal waters. They guessed typical salmon behavior pattern in homing migration based on

temperature history of chum salmon, Oncorhynchus keta, recovered.

We tagged 25 chum salmon with new model archival tags, which can record the fish's

internal temperature, water temperature, light intensity levels (for location), and depth, and

released in the Bering Sea. Three chum salmon tagged were recaptured in coastal waters of

Hokkaido. We analyzed data collected from these archival tags and found four typical

behavior patterns for homing migration. We also tried to relate these behavior patterns with

homing migration system for location and orientation and proposed a hypothesis for the

mechanism of the migration.

Materials and methods Archival tag and functions

Archival tags are data loggers that contain sensors with an accurate clock (for

physical conditions such as temperature, light, and depth) capable of recording data into

computer memory for retrieval later. The archival tag which we used in this study was

2

manufactured by Northwest Marine Technology (NWT) , Shaw Island, WA, records the fish's

internal temperature, water temperature, light levels (for location), and depth. In this

report, the NWT tag is referred to as an archival tag.

Sampling fish and fish selection

We used the Research Vessel Wakatake-maru (666 gross tonnage, chartered by

Fisheries Agency of Japan (FAJ» for the tagging experiments in the Bering Sea. The

longline was used for catching chum salmon keeping alive. The longline was set 30 minutes

before sunset and was hauled 30 minutes after sunset. The longline comprised 30 hachi

(overall length 3.32 km; 1 hac hi is 110.68 m long and has 49 hooks) and was baited with

salted Japanese anchovy (Engraulis japonicus). A few of chum salmon salmon caught by the

longline were selected for tagging with archival tags.

We used subjective criteria to evaluate if a large chum salmon was likely to be

maturing. If the scales were slightly more difficult to remove and the skin appeared to be

thickened, then we judged the fish to be maturing. The scale pattern criterion we used to

"identify" a Japanese chum salmon was if the circuli count in the first year was greater than

or equal to 30 and the circuli count in the second year less than or equal to 15. Then we

considered the fish to be returning to Japan (Ishida and Takagi, 1988).

To examine chum salmon scale Patterns, a large healthy fish was removed from the

recovery tank and placed individually into a second, smaller tank. A preferred scale was

removed from chum salmon and viewed with a microfiche reader to count the circuli in the

first two ocean zones. If the scale exhibited the scale Pattern typical of a Japanese chum

salmon, then the fish was moved into a third tank where fish selected for archival tagging

were placed. If the fish scale did not have a Japanese scale pattern, then the fish was not

used for archival tagging.

Fish handling

The archival tag was placed in the visceral cavity of chum salmon. No anesthetics

were used on the fish. The archival tag and tools were sterilized with ethanol. The fish was

disk-tagged and then turned over onto its back. A lengthwise incision, approximately 4-cm

long, was cut between the pelvic fins and the anal fin slightly to the left of the ventral mid

line. The tag was inserted into the body cavity and the external sensor wire was allowed to

trail out of the fish at the site of the incision. The incision was closed with two or three

stitches. After the operation was completed, the fish was released to the sea. In total, 25

chum salmon were tagged with archival tags and released in the Bering Sea (Table 1).

3

Analysis for data collected from archival tags

Based on light data, we presumed time of sunrises and sunsets. Day lengths and

midday were calculated from time of sunrise and sunset. We determined daily longitudes of

locations of tagged fish from the midday and determined the daily latitude from the day

length. When determining geolocation based on light data, determination of the latitude

often has serious error (for example, Block, 1998). We corrected latitude measurements by

comparing temperature history of the archival tags and sea surface temperatures (SST)

charts published by Japan Fisheries Information Service Center (FISC) when we could not

accurately determine latitude from light data. We presumed vertical movements from data

on the water pressure of the archival tag. We also compared horizontal location of tagged fish

with vertical movement. Lastly we considered homing behavior system of chum salmon in

offshore waters.

Results Recovery of the fish tagged

Three chum salmon tagged were recovered in the set net of coastal waters of

southeastern Hokkaido in the autumn of 1998 (Table 2). We confirmed that all fish were

mature and were close to spawning. Traumas by insertion of an archival tag were

agglutinated. We could perfectly read all data from archival tags.

Migration routes of the fish

We showed daily locations of the fish that were estimated from light and

temperature data (Fig. 1). The fish roughly seem to take the shortest route between the

release and recovery sites.

Vertical behavior of the fish

Depths of the fish were calculated from water pressure data. Data series of depths

and temperatures were shown in Fig. 2. This indicates that there are four typical patterns

in the vertical movement of the fish as following (see Fig. 4).

(1) Pattern-A (the first half, (6-15 days): Chum salmon momentarily dived just after release.

After that, the fish returned to the surface waters and spent a great portion of time in

the surface waters in the period immediately following tagging (7-10 days).

(2) Pattern-B (47-77 days): Pattern-B (47-77 days): Chum salmon frequently repeated to

dive into mid waters and to rise to surface waters (the up-and down behavior) at daytime.

They rose to surface waters and stayed there through nighttime. The up-and-down

4

behavior continued for 60-80 days. Diving depths were comparatively shallow in the

early morning and evening while being deep at midday. Pattern-B can be divided into

three sub-patterns as following.

1) Pattern-B-a (12-23 days): The up-and-down behaviors were repeated not so

frequently and diving depths were comparatively shallow.

2) Pattern-B-b (19-28 days): The up-and-down behaviors were repeated frequently and

diving depths were comparatively large (maximum about 60m).

3) Pattern-B-c (16-26 days): The up-and-down behaviors were repeated not so

n:equently and diving depths were comparatively shallow again. The fish

sometimes made the up-and-down behaviors at night and the typical behavior

patterns were sometimes unclear.

(3) Pattern-C ( 1 day): Chum salmon continuously submerged into deep layers (I50-300m)

during a day.

(4) Pattern-D (2-6days): Just after the continuous diving, frequencies of up-and-down

behavior at daytime decreased gradually. The fish increased a tendency to stay in

surface waters throughout day and night. This behavior pattern continued for 2-6 days

by the day when the fish were recaptured.

Relationship between water temperature and behavior

Because most of temperatures in abdominal cavity of the fish body and outer water

temperature did not have a difference, we did not get useful information from temperature

data in abdominal cavity. The range of water temperatures observed were from -1 to 18°C

(Fig. 1). When the fish took the up-and-down behaviors, differences in water temperature

between shallow waters and deep waters often became more than 7"C. Although various

patterns were found in the up-and-down behaviors at daytime, generally speaking, diving

depths were comparatively shallow in waters where surface water temperatures were cold

(7°C» while were comparatively deep in waters where surface water temperatures (1O"C<)

were comparatively warm.

Relationship between horizontal and vertical movements

To clarify relationship between horizontal and vertical movements, we put four

vertical behavior patterns on the tracks of the horizontal movements (Fig. 3). This shows a

specific vertical behavior pattern corresponded with the a specific horizontal movement and

as following.

(1) Pattern-A: Distances of horizontal movement were not long. It suggests that

5

chum salmon stayed in the vicinity of the release sites.

(2) Pattern-B: Distances of horizontal movement were very long. A great portion of

offshore homing migration was made in this pattern.

(3) Pattern-C: This patterns were found only on the ridge of the continental shelf of

Hokkaido or the Kuril Islands.

(4) Pattern-D: Distances of horizontal movement were very short. This patterns were

found in coastal waters of Hokkaido.

Discussion Interpretation of fish behavior

We showed schematic diagram of chum salmon migration and orientation based on

the following consideration (Fig.4).

Chum salmon did not move long distance just after the release (Pattern-A).

Insertion of the archival tag is considered to give serious damage to the fish. Accordingly, the

fish must need some days for recuperation from the damage. We interpreted behavior of the

Pattern-A as a period for recuperation. Accordingly, the behavior ofthis period should not be

interpreted as normal behaviors of chum salmon.

In Pattern-B, the up-and-down behavior at daytime was very characteristic. We can

give three hypotheses to explain this specific behavior as follows.

(1) Making orientation and location for homing migration.

(2) Taking feed organisms, for example, large size zooplankton.

(3) Controlling body temperature.

We consider that the first hypothesis is most reasonable, because a great portion of

the up-and-down behavior was found at daytime and diving depths often well corresponded

with solar altitude. To carry out long distance migration, the fish needs both abilities to find

the direction and location relative to the destination. Many migratory animals are believed

to know the direction and location using solar altitude and their inner biological clock.

Foggy weather peculiar to the northern North Pacific usually makes chum salmon difficult to

directly observe solar positions. However, we indicate that there is possibility that chum

salmon can roughly estimate solar altitude by measuring vertical distribution of light

intensity in underwater, which is considered to drastically change by solar altitude. If chum

salmon can estimate solar altitude from light intensity distribution in underwater, they can

presume their location by measuring underwater light and their biological clock. Moreover,

Deutschlander et al (1999) reported that an eastern red-spotted newt, Notophthalmus

6

viridescens, exhibited magnetic orientation under long wave light (500nm<). Salmon is

known to well perceive long wave light (Flamarique and Hawryshyn, 1993). Because long

wave light has small attenuation in the sea as compared with short wave light, chum salmon

can effectively utilize long wave light in deep waters where they dived.

Chum salmon mainly eat large zooplankton in the offshore waters (for example,

Kanno and Hamai, 1971». A great portion oflarge plankton (for example, small crustacean,

amphipod and Euphausiid) is known to rise to surface waters at nighttime and to go down to

very deep waters at daytime (200m<, Taki et aI, 1996). Azuma (1992) and Davis et al (1998)

reported that chum salmon stomachs were filled with the food near the time of sunset and

that chum salmon continued feeding by midnight. Chum salmon ascended into surface

waters in the evening in the period ofPattern-B. These suggest that the ascending behavior

is strongly related to feeding activities. At daytime the zooplankton moved to the waters far

deeper than the waters in which fish were swimming. Accordingly, we thought that the up

and-down behavior at daytime was not so much related to feeding.

Chum salmon often moved into deeper waters when they swam in warm waters

(1O"C<). This suggests that there are some possibilities that chum salmon submerged to

control their body temperature by avoiding warm surface waters. However, chum salmon

stayed in warm surface waters through nighttime. Accordingly, it seems that there is no

reasonable reason that is sufficient for explaining that the the fish must control the body

temperatures only at daytime.

Pattern-C shows a specific diving behavior of salmon. Veno (1992) reported that

many mature chum salmon were often caught by bottom trawlers on the ridge of continental

shelf of Northern Honshu. This report well coincides with the behavior of Pattern-C.

Accordingly, we indicate that there are possibilities mature chum salmon universally carry

out this continuous diving behavior just before entering coastal waters. Chum salmon is

believed to be used olfactory sense for orientation to the natal river and coastal waters

(Hasler and Scholtz, 1983). Pattern-C behavior can be interpreted as a preparation for chum

salmon entering coastal waters. Chum salmon may reset their olfactory sense for

orientation in coastal waters by submerging into deep waters, where chemical environments

are much different from the surface waters.

In Pattern-D, chum salmon decreased frequencies ofthe up-and-down behaviors and

tended towards staying in surface waters. This probably indicates that chum salmon

changed navigation system from for the offshore waters (light using system) to for the coastal

waters (olfactory sense using system).

Behavior Patterns and distribution of oceanographic water masses

7

The histories of water temperatures and daily locations in Pattern-B showed that

chum salmon had passed through three oceanographic water masses. Pattern-B-a, -b, and -c

are found in the sub-arctic waters, in the transition domain, and in the Oyashio and its

frontal waters, respectively (Favorite et aI, 1976; Otani, 1991). Generally speaking, the degree

of transparency in the sub-arctic waters is usually smaller than in transition domain waters.

On the other hand, the transparencies of the Oyashio waters are empirically very small by

high concentration of phyto-plankton. Transparency is directly related to underwater light

distribution. Accordingly, we can suggest that differences in underwater light distribution

among these water masses may cause changes of behavior ofPattern-B.

References Azuma, T. 1992. Diel feeding habits of sockeye and chum salmon in the Bering Sea during the

summer. Nippon Suisan Gakkaishi 58: 2019-2025.

Block, B.A., Dewar, H., Williams, T., Prince, E.D., Farwell, C., and Fudge, D. Archival tagging

of Atlantic blue fin tuna (Thunnus thynnus tyhnnus). MTS journal. 32: 37-46.

Davis, N. D., Aydin, KY. and Ishida, Y. 1998. Diel feeding habits and estimates of prey

consumption of sockeye, chum, and pink salmon in the Bering Sea in 1997. (NPAFC

Doc. 363) FRI-UW-9816. Fisheries Research Institute, University of Washington,

Seattle. 24P.

Deutschlander, M. E., S. C. Borland, and J. B. Phillips. 1999. Extraocular magnetic compass

in newts. Nature 400: 324-325.

Flamarique, J. N. and Hawryshyn, C. W. 1993. Spectral characteristics of salmonid migratory

routes from southern Vancouver Island (British Columbia). Can. J. Auat. Sci. 50:

1706-1716.

Favorite, F., A. J. Dodimead, and K Nasu. 1976. Oceanography ofthe subarctic Pacific region,

1960-71. Int. North Pac. Fish. Comm. Bull. 33: 1-187.

Hasler, A.D. and A. T. Scholtz. 1983. Olfactory inprinting and homing In salmon.

Zoophysiology 14: 134P.

Ishida, Y., S. Ito, and K Takagi 1988: Stock identification of chum salmon Oncorhynchus keta

from their maturity and scale characters. Nippon Suisann Gakkaishi 55: 651-656.

Kanno, Y., and 1. Hamai. 1971. Food of salmonid fish in the Bering Sea in summer of 1996.

Bull. Fac. Fish. Hokkaido Univ. 22: 107-127. (In Japanese with English abstract)

Ogura, M. 1994. Migratory behaviors of Pacific salmon (Oncorhynchus spp.) in the open sea.

National Research Institute ofFal' Seas Fisheries Bulletin 31: 1-139.

Ogura M. and Ishida, Y. 1995. Homing behavior and vertical movementa of four species of

Pacific salmon (Oncorhynchus spp.) in the central Bering Sea. Can. J. Fish Aquat.

8

Sci. 52: 532-540.

Otani, K 1991. To confirm again the charcteristics of the Oyashio. Bull. Hokkaido. Natl. Fish.

Res. lnst, 55: 1-24.

Taki, K, Y. Kotani, and Y. Endo. 1996. Ecological studies on Euphausia Pacifica HANSEN

and seasonal change of its environment off Onagawa, Miyagi Prefecture. III.

Distribution and diel migration of Euphausia pacifica. Bull. Tohoku Natl. Fish. Res.

lnst. 58: 89-104.

Ueno, Y. 1992. Deepwater migrations of chum salmon (Oncorhynchus keta) along the Pacific

coast of northern Japan. Can. J. Fish. Aquiat. Sci. 49: 2307-2312.

Walker, v.R., Myers, KW., Davis, N.D., Aydin, KY., Frieland, KD., Carlson, H.R., Boehlert,

G.W., Urawa, S, Ueno, Y. and Anma, G. Temperature data tag records of thermal

habit of migrating salmonids in the North Pacific Ocean and Bering Sea in1998. J.

Fish. Oceanography (in press).

9

Table I. Archival tags released on chum salmon caught in the Bering Sea from longline fishing operations

conducted by the Wakatake maru in July] 998. FAJ=Fisheries Agency of Japan, FRI=Fisheries

Research Institute. X=unreadable age.

Archival Release Date Release Location Disk Tag Species FL Age Tag No. No.

Year Month Day Latitude Longitude FAJ FRI

164 98 7 3 5230N 17930W MM1223 LL2171 chum 619 0.4 181 98 7 4 5330N 17930W MM]275 LL2223 chum 612 0.4 209 98 7 5 5430N 17930W MM1332 LL2280 chum 585 0.4 256 98 7 5 5430N 17930W MM1333 LL2281 chum 670 0.4 282 98 7 6 5530N 17930W MM1401 LL2349 chum 632 0.4 286 98 7 7 5630N 17930W MM1458 LL2406 chum 580 0.3 3]9 98 7 7 5630N 17930W MM]459 LL2407 chum 625 0.4 293 98 7 7 5630N 17930W MM1460 LL2408 chum 575 0.3 328 98 7 8 5730N 17930W MM]544 LL2492 chum 575 x.x 654 98 7 9 5830N 17930W MM1629 LL2577 chum 590 0.3 844 98 7 10 5730N 17824W MM1708 LL2656 chum 585 X.x 837 98 7 10 5730N 17824W MMI709 LL2657 chum 565 X.x 87] 98 7 II 5730N 17730W MM1767 LL2715 chum 575 0.3 843 98 7 ] 1 5730N 17730W MM1768 LL27I6 chum 630 0.3 846 98 7 ] ] 5730N I 7730W MM1769 LL2717 chum 590 0.3 895 98 7 ]2 5630N 17730W MM]825 LL2773 chum 590 0.3 894 98 7 12 5630N ] 7730W MM1826 LL2774 chum 570 0.3 885 98 7 ]2 5630N 17730W MM1827 LL2775 chum 615 0.4 897 98 7 13 5632N 17832W MM]846 LL2794 chum 560 0.3 909 98 7 ]5 5630N 17830E MM1913 LL2861 chum 590 0.3 912 98 7 ]5 5630N 17830E MM19]4 LL2862 chum 530 0.4 922 98 7 ]5 5630N 17830E MM19]5 LL2863 chum 630 0.4 924 98 7 ]6 5630N 17736E MM195] LL2900 chum 555 0.3 926 98 7 16 5630N 17736E MM1952 LL2901 chum 580 0.3 929 98 7 16 5630N ]7736E MM1953 LL2902 chum 590 0.3

10

J,IOE 115 150 155 160 165 110 175 180 60 .-------~~--~----~_r--------------~----,

>" 40 ~

140

55N

50

45

140£

55N

, 50

45

150

145 150 155

256

160 170 , 190

894

160 165 170 115 180

895

Fig. 1. Map showing horizon tal movement of the fish tagged.

20

IV ~l Vi

r 15 ~

e f

" . 10

" " ~ f-

0000 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

Jul. 6 Jut 7 Jut 8 Jul. 9

20

I ,

15

E " 3 10 ~

I -

1 /

I I I i j . ,

15. E ,:: -"""-

I "' "' ~

~

~~ .

: 0000 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

Jul.l0.199S Jul.ll Jul.12 Jul.13 Jul.14

20

15

e ~ 10 ~ " E ,::

0 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

Ju1.15.1998 Jul.16 JuL11 Jul.18 Jul.19

20

15

e " " i

10

~ f-

0~'-r~r+-r~~~-r~~~~~r+~~~r+~~~~~~~~~~~~-r~~+4-r~~+4~~-+ 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12.00 00:00 12:00

Ju1.20.1998 Jul.21 Jul.22 Jul.23 Jul.24

--Ambient Temp. -- Swimming depth

Fig.2-1-l. Charts of the depth and temperature records from the chum salmon tagged

(No. 256). Shaded areas indicate that the chum salmon were in darkness.

50

:§ "' it a

100 .Ef E E .. '"

50

] -"

it 0

100 '" c E E .~

'" 150

200

50

:§

! 100 '" .~

.~

'" 150

200

50

]

~ 0

100 '" c E E • "

150

200

20

15 50

e :§ .c

" 1}

3 100 0

10 "" ',~

~ c E

~ .~ ;-

'" 150

200 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

JuL25.199B Jul.26 JuL27 JuLl8 JuL29

20

15 50

e :§ .c

" " " 3 0

~ 10 100

~ E

E .~ ~ '"

150

200 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

JuL30.199B Jul.31 t Aug. 1 Aug. 2 Aug. 3

20

15 50

E :§

" t ~ 10 100

0

"" .E

~ E E

~ '" </)

150

200 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

Aug.4.199B Aug. 5 Aug. 6 Aug. 7 Aug.8

~~-----r--------~~----~·50

+'II-"-I'--nl'<.-;;;+ 1 00

Aug. 9.1998 Aug.l0 Aug.11 Aug.12 Au •. 13

--Ambient Temp. --- Swimming depth

Fig. 2-1-2. Continued. (No.256)

20

50 15 :§

e t " 0 0 100 '" 10 c

~ E E

l1: ii ~ Vl

150

200

00:00 12.00 00:00 12:00 00:00 12:00

AugJ4.1998 Aug.1S Aug.16 Aug.17 Aug.18

20

50 15

:§

E t " 100

a

~ 10 'i Q E E " ~ Vl

150

200

00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

Aug.19.1998 f Aug.20 Aug.21 Aug.22 Aug.23

00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

Aug.24.1998 Aug.25 Aug.26 Aug.27 Aug.2B

10

5 .i-f --II-f!-+---t--H-illl-i

~ 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

Aug.29.1998 Aug.30 Aug.31 Sep.1 Sep.2


Fig. 2-1-3. Continued. (No. 256)

1

20

15 50

E :§ .c

v 1i

t 100 0

1O ·r g E '. f- U>

150

200 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

Sep.3.1998 Sep.4 Sep.5 Sep.6 Sep.7

20

15 50

E :§ .c

v 1i ~ 10 100

a M

11. .~ E E ~ ';:

<n

150

200 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00 00:00 12:00

Sep, 8,1998 Sep.9 Sep.l0



20

15 50

e ] :;

~ jI

100 0

i 10·

.~ E

~ ·i '"

150

200

00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06000 12:00 18:00 00:00 06:00 .12:00 18:00

Ju1.12.1998 Jul.13 Jul.14 Jul.15 Jul.16

20

15 50

e ]

v ! ! 10 100 '" c. '~ E .§ ~ ~ en

150

0 200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Ju1.17.1998 Jul.18 Jul.19 Jul.20 Jul.21

20

15 50

e :§ :5

i c. v

100 0

10 ~ c. ·E E .~ ~ (I)

150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

JUI.22.1998 Jul.23 Jul.24 Jul.25 Jul.26

20

15 50

e ]

I i 10

0 100 '" c

"- 'j; E E ~ 'i

(I)

150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 16:00 00:00 06:00 12:00 18:00

Ju1.27.1998 Jul.28 Jul..29 Jul..30 Jul.31


Fig. 2-2-l. Continued. (No.894)

/JJ

20

15 50

e :§ . t t 100

£:)

10 .. . 5 E

E .~ ,!: '"

lS0

200 00:00 06:00 12:00 18:00 00:00 05;00 12;00 18;00 00;00 06;00 12:00 lB;OO 00;00 06:00 12;00 18;00 00:00 06;00 12:00 18;00

Aug. 1.1998 Aug. 2 Aug. 3 Aug. 4 Aug. 5

20

lS 50

e :§ :5

; It 100

0

1 10 ,S E

E E ~ 'lE

In

150

200 00:00 06:00 12:00 18:00 00:00 06;00 12:00 18:00 00;00 06:00 12;00 18;00 00;00 06:00 12:00 18:00 00:00 06;00 12;00 18;00

l' Aug. 6.1998 Aug. 7 Aug, B Aug, 9 Aug,10

d

20

15 50

e :§

1 i 100 £:)

10

-r t ~ E ~ .•

'" 150

200 00;00 06;00 12;00 18;00 00;00 05;00 12;00 18;00 00;00 06;00 12:00 18:00 00;00 05:00 12:00 18:00 00;00 06;00 12;00 18;00

Aug.l1.1998 Aug.12 Aug.13 Aug,14 Aug.15

20

15 50

E ] :g .

'; ~ ~

10 100 '" .~ ~ ,~ ,!:

tn

150

200 00:00 06:00 12:00 18:00 00:00 06;00 12:00 18:00 00:00 06:00 12:00 lS;OO 00:00 06;00 12;00 18:00 00:00 06;00 12:00 18:00

Aug.16.199S Aug.17 Aug.18 Aug.19 Aug.20


Fig.2.2·2. Continued. (No.894)

/9

20

15 50

e ]

t ~ 100

0 10 ~

.~ ~ .~ ,! (f)

150

200 00,00 06,00 12:00 16,00 00,00 06,00 noo 16,00 00,00 06,00 1Z,00 18;00 00,00 06:00 lZ,OO 16:00 00,00 06,00 12:00 lS,OO

Aug.21.1998 Aug.22 Aug.23 Aug.24 Aug.25

20

15 50

E ]

t ~ 10 100

0

~ .. . ~

! E .~

'" 150

200

Aug.26.199B Aug.27 Aug.2B Aug.29 Aug.30

20

15 50

e ]

i ! 10 100

0

i!

" 'j;

E .~ ~ en

150

200 00,00 06,00 12:00 16:00 00,00 06:00 12,00 18:00 00,00 OMO 12:00 lMO 00:00 06:00 12:00 18,00 00:00 06:00 12,00 16:00

Aug.31.1998 Sop. 1 Sop. 2 Sep.3 Sep.4

20

15 50

E ] ~ e .

~ 10 0

100 .. 1i -~ E .~ ,!:

en

150

200 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Sep. 5.1998 Sep.6 Sep.7 t Sep.8 SoP. 9



11>

20

15 50

e :§

i

t 100 0

1O -i .~

~ '" 150

200

00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 08:00 12:00 18:00

Sop.l0.1998 Sop.ll Sop.12 Sop.13 Sop.14

20

15 50

e ]

t ~ 100

0

! 10 l!'

'il E .~

'" 150

200 00:00 08:00 12:00 18:00 00:00 06:00 12:00 lB:OO 00:00 06:00 12:00 lB:OO 00:00 06:00 12:00 18:00 00:00 06:00 12:00 lB:OO

Sep.15.199S Sep,16 Sep.17 Sep.18 Sep.19

20

15 50

e ] '"

~ it

100 0

10 ~

~ C

0. 'il E .j ,!! <J)

150

200

06:00 12:00 18;00 00:00 06;00 12;00 18:00 00;00 06:00 12:00 18:00 00;00 06:00 12:00 18:00 00;00 06:00 12:00 18:00

Sop.20.199B Sop.21 Sop.22 Sop.23 Sop.24

20 0

15 50

e ]

l

i 10 100 0

l!' ·s E

~ "

II)

150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Sop.25.199B Sop.26 Sop.27 Sop.2B Sop.29

--Ambient Temp, -- Swimming depth

Fig.2-2.4. Continued. (No.894)

20

15 50

] e :5

~ It 0

I 10 100 I! ·6

E E ~

.ji

'" 150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Sep.30.1998 Oct. 1 Oct. 2 Oct. 3 Oct. 4

20

15 50

e ]

t t 10

0 100 .,

e E ·i ~ VI

150

200 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:QO 18:00

Oct. 5.1998 Oct. 6 0.t.7 Oct. 8 Oct. 9

,

20

15 50

e ] "%

~ v

0

1 10 100 ~ ·e E .~ ~ Vi

150

00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Oct.10.1998


Fig. 2·2·5. Continued. (No.894)

2Q

20

15 50

E ] .J:: 'ii u ~ ~ 10 100 .Sf ~ E Q. E E

o! .~

en

150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Ju!.12.1998 Jul.13 Jul.14 Jul..1S Jul.16 r-20

15 50

E :§ ..e

u fr i 100

0 10 '" .E E ~ E

~ ., en

150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:0'0 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Ju!.17.1998 Ju!.18 Ju!'19 Jul.20 Jul.21

20

15 50

e :§ :a v .

I 100 0

10 .~ 0. f ·E E .~ ~ en

150

00:00 06:00. 12:00 18:00 00:00 06:00 12:00 1 e:oo 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 1 e:oo

Jul..22.1998 t Ju!.23 Jul.24 Jul.25 Ju!'26

15 50

e ]

i i " 0 10 100 '" < ·E ~ E ~

., en

150

00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Jul.27.1998 Jul.2B Jul.29 Jul.30 Jul.31



2/

20

15 50

E ] .<:

~ i

i 100 Cl

10 '" .5 E

~ E

~ .~

(I)

150

200 00;00 06:00 12:00 18:00 00:0(} 06:00 12,00 18;00 00,00 06,00 12:00 18:00 00:00 OMO 12,00 18,00 00,00 06,00 12,00' 18;00

Aug. 1.1998 Aug. 2 Aug. 3 Aug. 4 Aug.~

20

15 50

E ]

v 1 3

~ 10 100 '" .5

~ E

·i ~ en

150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 16:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 16:00 00:00 06:00 12:00 18:00

Aug. 6.1998 Aug, 7 Aug. 8 Aug. 9 Aug.tO

20

15 50-

e ]

t ! 100

Cl 10 ~ 'e

~ E

~ .~

m

150

° 200

00,00 06,00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Aug.1U998 Aug.t2 t Aug.13 Aug.14 Aug.tS

20

15 50

E ]

i 1 10 100 ..

. ~ ~ E ~

"

m

150

200

00:00 06:00 12:00 16:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 16:00 00,00 06:00 12:00 18:00

Aug.16.1998 Aug.17 Aug.18 Aug.19 Aug.20



</

20

15 50

E ] :5

~ 5l'

100 0

i 10 ·r

E . <it f- en

150

200

00:00 06:00 12:00 18:00 00:00 06:00 12:00 16:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 16:00 00:00 06:00 12:00 18:00

Aug<21.1998 Aug<22 Aug.23 Aug<24 Aug<25

20

15 50

e ] -5

t fr

100 0

10 .~ E

E E . .,. I- en

150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Aug<26<199B Aug.27 Aug.28 Aug.29 Aug.30

20

15 50

E ] .c 'a

i .

100 0

10 ~ 's E E ~ 'i

en

150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Aug.31 < 1998 Sep.l Scp.2 Sep.3 Sop. 4

20

1; 50

E ]

~ i 0 e 10 100 l!

~ <e E E ~ <~

Y>

150

200 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

s.o< 5.1998 Sep.6 Scp.7 Sep.8 f Scp.9



20

15 50

e ]

e t 5

100 0

<;;; 10 .~ U

~ E . .~ .... U)

150

200 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Sop.l0.1998 50 •. 11 So •. 12 So •. 13 50 •. 14

20 0

15 50

e ] -5

! it

10 100 0

'" C

0. ·e E E ,! .,

en

150

200 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06:00 12:00 18:00 00:00 06;00 12:00 18:00 00:00 06:00 12:00 18:00

Sop.15.1998 5.p.16 Sop.17 S.p.18 So •. 19

20

15 50

e ]

i j 100

0 10 .(

0. E E ,! ~

150

200

00:00 06;00 12:00 18:00 00;00 06:00 12;00 18:00 00:00 06:00 12:00 18:00 00;00 06:00 12:00 18:00 00:00 06:00 12:00 18:00

Sop.20.1998 50p.21 50 •. 22 50 •. 23 50 •. 24

20

15 50

e ]

t i 10 100 0

" I .E E E

,! ., en

150

200

00:00 06:00 12;00 18:00 00:00 06:00 12:00 18:00 00:00 06;00 12:00 18:00 00:00 06;00 12:00 18;00 00:00 06:00 12:00 18:00

Sop.25.1998 So •. 26 500.27 So •. 28 S ••. 29


Fig. 2·3·4. Continued. (No. 895)

E

i E ~

20

15 50

10 100

150

O+-~~~+-~-+-r4-~-+~~~-+-r4-~-+~4-~-+~+--+~4-+--+~~~-+~+-~~4-~-+~~~-+~4-~200 00;00 06;00 12;00 18;00 00;00 06;()0 12;00 1 B;()O 00;00 06;00 12;()0 18;00 00;00 06;00 12;00 18;00 OO;()O 06;00 12;00 18;00

Sep.30.1998 Oct. 1



:g -" fr 0

·r E .. '"

170

150 160 170

55

50

45

E 180 ,

Pattern A (JuI.l2·Ju1.l8)

)

~. Pattern Ba

(1ul.I 9·Ju1.24)

E 180 W

Pattern A (JUI.12.JUI.~

~ Pattern Ba (JuI.23·Aug.I)

Fig.3. Charts showing four vertical behavior patterns on the tracks of the horizontal

movements.

I..:J .....:::l.

Pattern

Typical Vertical Movement

Behavior and Significance

Area

Duration

Pattern-A Pattern-B Pattern-C Pattern-D

«i) «~ « i)« a

v------- 'vvvwvw-b

c

~.... .... .... .. Recuperation period

Staying in surface waters. Recovering from trauma of tag

insertion.

Vicinity of Release Site

6-15 days

Offshore Migration Period

Location and orientation using light intensity or solar compass (?) and migration towards natal area at

daytime. Feeding activity at night.

Bering Sea and offshore waters of North Pacific

I 47~77 cl~;~ -]

Transformation ... "' ...... u\.

Continuous diving for 1-17 hours. Transformation on orientation and maturation towards coastal waters and natal rivers.

Ridge of Continental Shelf

1 day (1-17 hours)

Coastal Migration Period

Gradual change in orientation from for offshore system to

coastal system (olfactory sense)

Coastal waters near natal rivers -I

r2-6 days

Fig.4 Schematic diagram of basic behavior and orientation system of chum salmon in homing migration.

Table 1. Archival tags released on chum salmon caught in the Bering Sea from longline fishing

operations conducted by the Wakatake maru in July 1998. FAJ=Fisheries Agency of Japan,

FRI=Fisheries Research Institute. X=unreadable age.

Archival Release Date Release Location Disk Tag Species FL Age Tag No. No.

Year Month Day Latitude Longitude FAJ FRI

164 98 7 3 5230N 17930W MM1223 LL2171 chum 619 0.4 181 98 7 4 5330N 17930W MM1275 LL2223 chum 612 0.4 209 98 7 5 5430N 17930W MM1332 LL2280 chum 585 0.4 256 98 7 5 5430N 17930W MM1333 LL2281 chum 670 0.4 282 98 7 6 5530N 17930W MM1401 LL2349 chum 632 0.4 286 98 7 7 5630N 17930W MM1458 LL2406 chum 580 0.3 319 98 7 7 5630N 17930W MM1459 LL2407 chum 625 0.4 293 98 7 7 5630N 17930W MM1460 LL2408 chum 575 0.3 328 98 7 8 5730N 17930W MM1544 LL2492 chum 575 x.x 654 98 7 9 5830N 17930W MM1629 LL2577 chum 590 0.3 844 98 7 10 5730N 17824W MM1708 LL2656 chum 585 XX 837 98 7 10 5730N 17824W MM1709 LL2657 chum 565 X.x 871 98 7 11 5730N 17730W MM1767 LL2715 chum 575 0.3 843 98 7 11 5730N 17730W MM1768 LL2716 chum 630 0.3 846 98 7 11 5730N 17730W MM1769 LL2717 chum 590 0.3 895 98 7 12 5630N 17730W MM1825 LL2773 chum 590 0.3 894 98 7 12 5630N 17730W MM1826 LL2774 chum 570 0.3 885 98 7 12 5630N 17730W MM1827 LL2775 chum 615 0.4 897 98 7 13 5632N 17832W MM1846 LL2794 chum 560 0.3 909 98 7 15 5630N 17830E MMI913 LL2861 chum 590 0.3 912 98 7 15 5630N 17830E MM1914 LL2862 chum 530 0.4 922 98 7 15 5630N 17830E MM1915 LL2863 chum 630 0.4 924 98 7 16 5630N 17736E MM1951 LL2900 chum 555 0.3 926 98 7 16 5630N 17736E MM1952 LL2901 chum 580 0.3 929 98 7 16 5630N 17736E MM1953 LL2902 chum 590 0.3

I'.l, .......!)

Table 2. Release and recovery information for three chum salmon tagged with archival tags in the Bering Sea in 1998 and recovered in

Hokkaido. Days: days between release and recovery days. Distances: shortest distance between release and recovery sites. Tag No Release Recovery

Date Location FL(mm) Age Date Location FL(mm) Days Distance(km) Sex 256 7/5/98 Bering Sea 670 0.4 9/10/98 Hokkaido coast 690 68 2791 female

54·30N 43·54N 179·30W 145·06E

894 7/12/98 Bering Sea 570 0.3 10/10/98 Hokkaido coast 598 87 2998 female 56·30N 43·51N 17·30W 145·06E

895 7/12/98 Bering Sea 590 0.3 10/3/98 Hokkaido coast 598 84 2402 female 56-30N 43·20N 17·30W 145·22E

homing behavior of chum salmon determined by an archival tag

Documents