‫ުݽ‬8Fisheryल൥ȁ࣪࿥‫ૂުݽ‬༭΍ȜΫΑΓϋΗȜ
Katsuya Saitoh
Japan Fisheries InformationService Center8.1 ඾ུ͈‫ે࡛͈ުݽ‬Present Status of Japanese Fisheries
5,000,000

4,500,0004,000,000̯͊Mackerl΃Μ΂
Skipjack
ΑΉΕ;Θρ
Walleye pollack

3,500,000

Landed Quantity [ ton ]ζͼχΏSardine
3,000,000

2,500,000

2,000,000

1,500,000

1,000,000

500,000

0
1964

1970

1976

1982

1988

1994

2000

Year

଎ġġġ8.1.1 ৽ါ‫ݿ‬ਅ͈କလ̬͈ଔ֊
Fig. 8.1.1 Catch history of main fishes in Japan1996ා7࠮20඾ͤ͢Ȃ඾ུͅచ̱࣭̀͜Ⴒ٬ဢ༹ૄ࿩̦࢘ႁͬ୆̲Ȃུ‫ڒ‬എ̈́200٬ၖশయͅඏව̱̱̹͘ȃ̵̭ࣣͦͩ̀ͅ඾ུ͉٬ဢ୆໤঩࡙͈༗ం̤͍͢‫ۯ‬ၑͅ‫ၙ༹̳ͥ۾‬ͬଷ೰̱Ȃ200٬ၖඤ͈କॲ঩࡙‫ۯ‬ၑͬ‫ٳ‬ই̱̱̹͘ȃ
଎8.1.1͉Ȃ৽ါ‫ݿ‬ਅ͈କလ̬͈ଔ֊Ȫ෠ႅൡࠗȫ̳́ȃକॲ঩࡙͉ఱܰ࿅̈́௩‫ح‬Ȇࡘઁͬ߫ͤ༐̱̳͘ȃ঩࡙་൲͈ࡔ֦͉Ȃ٬ဢ۪‫͞ޏ‬༛૙Ȇ๭૙̈́̓အș̈́ါ֦̦ໝॠͅ‫̱߸۾‬̞̳̦̀͘Ȃ‫ڰުݽ‬൲̷͈̳֚̾́͜ȃ঩࡙‫ۯ‬ၑ͉࢘ͅၚഎ̈́ௌު̦ຈါະ‫̳́ࠧخ‬ȃ࢘ၚഎ̈́ௌު͉ͅ٬ဢ۪‫߲ݿ͞ޏ‬໦ື൝͈ૂ༭̦ਹါ̜́ͤȂକ‫ૂأ‬༭͉ड͜‫ܖ‬ய͂̈́ͥૂ༭͈̳͌͂̾́ȃThe United Nations Convention on the Law of the Sea became effective on July 20, 1996, enabling
Japan to recognize a exclusive economic zone (EEZ). Japan established the laws concerning thepreservation and management of marine resources in connection with this and began managing
marine resources in the area within EEZ.
Fig. 8.1.1 depicts the transition of the catches of the main species of fish (annual report on fisheries).
Marine resources repeatedly exhibit large increases and decreases. Although various factors, such asthe oceanic environment and predation, relate to these fluctuations of resources in a complex manner,fishing activities are one of the principal factors. Efficient fishing is essential for fish resourcemanagement. To accomplish this, information of marine environment and fish school distribution isvery important, together with information on water temperatures as one of the most basic items.

49

8.2 ‫͈͒ުݽ‬କ‫ૂأ‬༭͈؊ဥ

Application of Water Temperature to Fishery̧͘࿌ȪζΈυȫPurse seine (Tuna)ͼ΃೦ͤ
Squid jigging

΍ϋζམ਋࿌ȁStick - held dip net (Saury)
50Ņ͘࿌ȪζΈυȫPurse seine (Tuna)̧͘࿌ȪζͺΐȂζ΍Ψȫ
Purse seine (Horse Mackerel, Mackerel)

45Ņ͘࿌Ȫζ΍ΨȂΑσιͼ΃ȫPurse seine (Mackerel, Squid)40N΃Μ΂‫ۮ‬೦ͤȁPole and line (Skipjack)̧͘࿌Ȫ΃Μ΂ȫPurse seine (Skipjack)

35Ņ͘࿌Ȇ೰౾࿌Ȫζ΍ΨȫPurse seine and set-net (Mackerel)
30Ņ͘࿌ȪζͼχΏȂζͺΐȫPurse seine (Sardine, Horse mackerel)
25Ņ͘࿌ȪήςȂζͺΐȫPurse seine (Anber Jack, Horse Mackerel)

20N
120E

125E

130E

135E

140E

145E

150E

155E

160E

165E

170E

175E

180

଎ġġġ8.2.2 ࡛ા۷௶ΟȜΗ͈ߗ‫ۼ‬໦ື
Fig. 8.2.2 Spatial distribution of ship observation data June 1 - 10, 2001

଎ġġġ8.2.1 ‫ૂުݽ‬༭Ȫ‫ڎ‬౷͈କလ̬ȫ2004ා8࠮ಎ੐
Fig. 8.2.1 Fishing ground map Aug. 10 - 20, 2004

Fig. 8.2.1 illustrates the distribution of fishing areas in mid-August 2004. Fish are sensitive to thewater temperature. Therefore, fish distributed in the warm-current areas prefer relatively warm waterand those distributed in the cold-current areas prefer relatively cold water; this is called the optimum଎8.2.1͉Ȃ2004ා8࠮ಎ੐͈‫ݽ‬ા͈໦ື̳́ȃ‫͉ݿ‬ਔ͈ͤକ‫ͅأ‬ຮ̳ۜ́ȃ̭͈̹͛Ȃ౰ၠ֖ͅ໦ື̳ͥ‫͉ݿ‬௖చഎͅ౰̥̞କͬࢡ͙Ȃ‫ێ‬ၠ֖ͅ໦ື̳ͥ‫͉ݿ‬௖చഎͅ႖̹̞କͬࢡ͙̳͘ȃ̭͈୆௳ͅഐ̱̹କ‫ͬأ‬ഐକ‫̳̞́ͭ͘ࡤ͂أ‬ȃഐକ‫ࡢ͉أ‬ఘओٝ͞ဋশ‫ܢ‬̽̀͢ͅఱ̧̩་൲̱̳̦͘Ȃ‫ུܖ‬എͅ‫͈ݿ‬ਅ႒̽̀͢ͅ։̞̳̽̀͘ȃ‫̞̤̀ͅުݽ‬କ‫͉أ‬ड͜ਹါ۪̈́‫ૂޏ‬༭͈̳֚̾́ȃ‫ݽ‬ાັ߃͈କ‫ૂأ‬༭͉Ȃ಺औ஑͞ήͼȂ‫ݽ‬஑൝̥ͣං̧̭̦̳̦ͥ͂́͘Ȃ̷͈ତ͉ࡠ̞̳ͣͦ̀͘ȃ଎8.2.2͉Ȃ‫ૂުݽ‬༭΍ȜΫΑΓϋΗȜ̦2001ා6࠮1඾ȡ10඾ͅਓਬ̱̹඾ུਔ༏٬֖͈କ‫أ‬ΟȜΗ͈պ౾͈໦ື଎̳́ȃ٬ဢΟȜΗ͈ਓਬ̤̞̀ͅȂ࡛ા́ೄ୪
۷௶̯̹ͦΟȜΗ͈ਓਬ͉ͅশߗ‫ۼ‬എ̈́༊̦̠̱ͤ̓̀͜ంह̱̳͘ȃ̭ͦͬ༞̠͈֚̾
༹༷̦ςκȜΠΓϋΏϋΈ̳́ȃ‫ުݽ‬໦࿤͉́‫خ‬ণȡ୤‫ٸ‬෨ಿͬ၌ဥ̱̹ςκȜΠΓϋΏϋΈ̦ड͜၌ဥ̧̯̱̹ͦ̀͘ȃ

50temperature. Although the optimum temperature varies largely depending on differences between
individuals and the season of migration, it basically varies from one species of fish to another. Forfishing operations, water temperature is one of the most important pieces of information about theenvironment.
Water temperature information around fishing areas can be obtained from research vessels, buoys,
and the fishing boats themselves, but their actual number is somewhat limited. Fig. 8.2.2 illustrates
the distribution of water temperature data in the sea around Japan collected by the Japan Fishery
Information Service Center from June 1 to 10, 2001. Collecting marine data inevitably involves
temporal and spatial biases that are directly observed at each site. Remote sensing complements
this data collection. In the field of fisheries, remote sensing using infrared wavelength is being utilized
more frequently.

8.3 ‫خ‬ণȡ୤‫ٸ‬Γϋ΍Ȝ͂ζͼ·υ෨༶ৣࠗ

Visible and Infrared Sensors and Microwave Radiometers଎ġġġ8.3.1 2004ා10࠮18඾͈AMSR-E SSTْ௨Ȫऒȫ͂൳඾͈NOAA / AVHRR SSTْ௨ȪֲȫFig. 8.3.1 Comparison between AMSR-E SST image (left) and NOAA / AVHRR image (right) on Oct. 18, 2004‫̞̤̀ͅުݽ‬Ȃ೰ુഎͅΟȜΗ̦ං̭͉ͣͦͥ͂Ȃड࿹୶ম̳ࣜ́ȃ‫͈͒ުݽ‬؊ဥ̤̞̀ͅȂAMSR - E͈࿹պ଻͉‫ͬޣג͈׌‬਋̫̩̞̭̳͂́ͅȃ଎8.3.1͉AMSR - E͂NOAA/AVHRRͥ͢ͅນ࿂କ‫أ‬ȪSSTȫْ௨͈๤‫̳́ڛ‬ȃ൳඾͈AMSR-EȪζͼ·υ෨෨ಿȫ͂AVHRRȪ‫خ‬ণȡ୤‫ٸ‬෨ಿȫْ͈௨͈๤‫̥ͣڛ‬Ȃ‫̧̦̭͙͉̞֑͈́͂ͥ͂ͤ̽ͬޣג͈׌‬̧̳͘ȃࣽࢃAMSR-Eͅ௽̩ζͼ·υ෨ͬ၌ဥ̱̹‫ିמ‬Γϋ΍Ȝ̽̀͢ͅȂࢵͅୈഽၻ̩Ȃٜࣞ௨ഽ́ນ࿂କ‫أ‬ΟȜΗ̦৾ං̯̭̦ͦͥ͂‫ܢ‬ఞ̯̳ͦ͘ȃ

Obtaining data constantly is a matter of the highest priority for fishing operations. The advantage ofAMSR-E for fisheries is that it is scarcely influenced by clouds. Fig. 8.3.1 shows the comparison
between the AMSR-E sea surface‫ޓ‬temperature (SST) image and that of the NOAA/AVHRR.‫ޓ‬Comparing images of AMSR-E (microwave wavelength) with those of AVHRR (visible and infraredwavelength) on the same day clearly demonstrates the difference in the influence of clouds. Seasurface temperature data will be collected with greater accuracy and higher resolution in the futureusing satellite-mounted sensors that utilize microwaves following AMSR-E.

51

8.4 AMSR-E ٬࿂କ‫ْأ‬௨͂‫ݽ‬ાպ౾AMSR-E Sea Surface Temperature Images and the Locations of Fisheries଎8.4.1́Ȃؕ૗̞ζȜ΃Ȝ͉ͼχΏȆ΍Ψ̧͘࿌‫ݽ‬ાȂ୒̞ζȜ΃Ȝ͉΃Μ΂‫ۮ‬೦ͤ‫ݽ‬ાȂ୤̞ζȜ΃Ȝ͉ζΈυ൝‫װ‬ථ‫ݽ‬ાȂႂ૗͈ζȜ΃Ȝ͉΍ϋζམ਋࿌‫ݽ‬ાͬা̱̞̳̀͘ȃ‫ݽ‬ા͉Ȃ‫ڕݽ‬చય‫ݿ‬ਅ͈ഐକ‫଼̳̞̯̀ͦ͘ࠁ́أ‬ȃඅͅඅಭഎ͈͉̈́΍ϋζ‫ݽ‬ા́Ȃ2003ා͉૶ಲ̦
ࢩ̩ධ‫̱̀ئ‬Ȃ‫ݽࣣؗͅ‬ા̦ࠁ଼̯̱̹ͦ͘ȃ༷֚2004ා͉౰କ̦ٞൽ൐ͅ໦ື̱Ȃ‫ݽ̞ͅ״܅״‬ા̦ࠁ଼̯̱̹ͦ͘ȃ΃Μ΂‫ݽ‬ા͜2003ා͈̭͈শ‫͉ܢ‬‫ݽ͈ࣣؗ‬ાࠁ଼̱̹́ȃIn Fig. 8.4.1, yellow indicates the purse seine fisheries
areas for sardines and mackerels; blue, the pole and line
fisheries areas for skipjack, red, the long line fisheries areas
for tuna, and green, the stick-held dip net fisheries areas for
0612182430 [Ɏ]sauries. Each fishing area has a optimum temperature foreach particular species of fish.
The fishing area for sauries is particularly interesting. It
was formed when the Oyashio current went widely to thesouth in 2003. In 2004, the fishing area was formed along
the coast as the warm water-mass ranged to the east ofHokkaido. In the 2003 season, the fishing area for bonitoes
was also formed far offshore.

଎ġġġ8.4.1 2003ා10࠮19඾ȡ21඾Ȫષȫ͂2004ා10࠮19඾ȡ21඾Ȫ‫ئ‬ȫ͈AMSR-ESSTْ௨ͅȂ̭͈শ‫ݽ͈ܢ‬ાպ౾ͬίυΛΠ̱̹଎Ɏ]52Fig. 8.4.1 AMSR-E SST image with fishing ground Oct. 19-21, 2003 (top) andOct.19-21, 2004 (bottom)

8.5 ‫ૂିמ‬༭൝ͬໝࣣ၌ဥ̱̹٬‫ޙ‬଎Sea Condition Diagram Utilizing a Combination of Satellite Information଎ġġġ8.5.1 ࡛ાΟȜΗ͞‫ିמ‬ΟȜΗͬໝࣣഎͅழ̵͙ࣣ̹ͩSST଎Ȫ2004ා8࠮5඾ȫFig. 8.5.1 SST image Aug. 5, 2004 by multi sensor and observation data

଎8.5.1͉ȂAVHRR͞AMSR-Ë͈́̓‫ିמ‬ΟȜΗ͞Ȃ஑ตକ‫ܨ͞أ‬ય಩൝͈ٜଢ଼̽͢ͅ
̀ං̹ͣͦକ‫أ‬ΟȜΗͬ௙ࣣഎͅழ̵͙ࣣͩ̀ै଼̯̹ͦນ࿂କ‫أ‬଎̳́ȃAMSR-É͉̭͈̠̈́͢મळٜ̈́௨ഽ́କ‫ͬأ‬ං̭̦ͥ͂੄ြ̵̦ͭ͘Ȃఈ͈‫͞ିמ‬ΟȜΗͬழ͙ࣣͩ
̵̭ͥ͂́Ȃࢩ֖͈଎ͬै଼̳̭̦ͥ͂‫خ‬ෝ̳́ȃζσΙΓϋ΍ȜςκȜΠΓϋΏϋΈ͉̭̥͈ͦͣςκȜΠΓϋΏϋΈ͈༷࢜଻̳́ȃAMSR-Ë͈̠́͢ζͼ·υ෨Γϋ΍Ȝ͉Ȃ‫خ‬ণȆ୤‫ٸ‬Γϋ΍Ȝ͂໼͐‫ུܖ‬എ̈́Γϋ΍Ȝ̈́ͥ͂ͅ‫ܢ‬ఞ̯̳ͦ͘ȃ

Fig. 8.5.1 presents a SST image prepared from a comprehensive combination of SST dataobtained from satellite sensors including AVHRR and AMSR-E, ship observation water temperatures,and water temperature analyses such as by JMA. Though it is impossible to obtain SST data at sucha fine resolution with AMSR-E only, it becomes possible to prepare a diagram covering a wide range
by combining other satellite data. Multi-sensor remote sensing will be the direction of the future, and
it is expected that microwave sensors such as those of AMSR-E will become the basic sensors
comparable with visible and infrared sensors.

53