Classic MSY theoryClassic MSY theory

400iv

ety

200

300

odu

cti

100

200

lus

pro

0

100

surp

l

0 500 1000

stock biomass

Requiem to MaximumRequiem to Maximum Sustainable Yield Theoryy

• Ecosystems are uncertain, non-equilibrium and complexand complex.

• MSY theory ignores all the three.• Does MSY theory

guarantee species 120

nguarantee species persistence?

No!! 6080

100生産力 ro

duct

ion

- No!!2040

力

urpl

uspr

200 400 600 800 1000

親魚量Stock abundance

su

The tragedy of the commons(Hardin 1960)

• Open access fisheries promotes overexploitationEEZ b UNCLOS (1996)• EEZ by UNCLOS (1996)

dR/dt = (K – E1 – E2 – R) RR k i E E fi hi ff f 2 fi hR：stock size; E1, E2 :fishing effort of 2 fishersEquilibrium R = K – E1 – E2

Catch F1=RE1=(K – E1 – E2)E1 F2=(K – E1 – E2)E2

Nash sol. ∂F1/∂E1= (K – 2E1 – E2) = 0, ∂F2/∂E2 = 0F1=F2=K2/9 at E1 = E2 = K/3, R = K/3 < RMSY

3

The tragedy of the commons④Try by yourself ④The tragedy of the

Equilibrium N 333 Equilibrium N 333Equilibrium N 333 Equilibrium N 333

e Catch e Catch

A 4 1,333.3 A 4 1,333

B 4 1,333.3 B 4 1,333

Total 8 2 667 Total 8 2 667Total 8 2,667 Total 8 2,667r= 12 K= 1000

1.Moderate e at MSY 2.Equal division for both profit 3.If A do cheating, B lose 5.If A do cheating more, both

ABC decision ruleABC decision rule

cien

t Fco

effic

ishi

ng

Estimate of stock biomass N

Fi

Estimate of stock biomass N

A simulation result of fisheries management

Nt

Ct

nt F

omas

s m

ount

oeffi

cein

ock

bio

atch

am

hing

co

Sto Ca

Fish

Year tYear t

Species replacement of plankton-feeding pelagic fish in Japanese waters

AnchovyJack mackerelPacific sauryon

s)

Pacific sauryChub mackerelJapanese sardine

1000

tond

ings

(La

n

Year

“Aging” of Japanesesardine during 1988 to 1991

Estimate of stock abundance of Japanese sardine in Kuroshio region( illi t ) 0 t 5

http://abchan.job.affrc.go.jp/digests15/details/1503.pdf

(million tonnes), age 0 to >5 yrs.

Japan Government agreed overfishingJapan Government agreed overfishingof sardine (TAC > ABC >> catch)( )

• Pacific saury Japanese sardine

サンマ イワシ

80

90

100

トン

）

サバ

60

70

80

トン

）

サンマ

70

80

ン）

マイワシ

000t

ons）

ン）

50

60

70

80

漁獲

量（万

40

50

60

漁獲

量（

万ト

40

50

60

漁獲

量（万

トン

catc

h（10

,0

獲量

（万

ト

20

30

40

AC

，A

BC

，漁

20

30

40

AC

，A

BC

，漁

20

30

40

TA

C，

AB

C，

漁

AC

,act

ual c

C,T

AC

,漁0

10

1997 1999 2001 2003

TA

0

10

1997 1998 1999 2000 2001 2002 2003

TA

0

10

1997 1998 1999 2000 2001 2002 2003

T

AB

C,T

A

AB

1997 1998 1999 2000 2001 2002 2003 1997 1998 1999 2000 2001 2002 2003

Recruitment of chub mackerelRecruitment of chub mackerel temporally fluctuated

=recruitment/spawning stock

Large year class appeared twicepp

Stock of Kuroshio Region

Overfishing of immature chub mackerelOverfishing of immature chub mackerel70年代 80年代 90年代 93年以降

尾数 65.0% 60.0% 87.0% 90.6%

4

lion)

0 1 2 3

4 5 6+

2

3

mbe

rs (b

ill 4 5 6+

1

2

ch i

n nu

m

d

0

1

Cat

c

01970 1975 1980 1985 1990 1995

If fishers conserve immatures like 1970 80s

120.0 10.00

s）

If fishers conserve immatures like 1970-80s

80.0

100.0

6 00

7.00

8.00

9.00

△（m

illio

nto

ns

mill

ion t

ons）

◆

40.0

60.0

3.00

4.00

5.00

6.00

Recru

itm

ent△

ng

biom

ass（

m0.0

20.0

0.00

1.00

2.00

1999 2004 2009 2014 2019 2024 2029

Cat

ch●

、

Spa

wni n

1999 2004 2009 2014 2019 2024 2029

Year

If fishers continue the overfishing of

immatures like 1990s

Risk assessment of stock recovery plan (“SMwE Operating Model”)

• Start age structure of the current stock; • Future RPS (αt) is randomly chosen fromFuture RPS (αt) is randomly chosen from

the past 10 years estimates of RPS. (include process errors)(include process errors)

• N0,t = SSBt αt/(1+β SSBt)0,t t t t

• Na+1,t+1 = Na,t exp[-M-Fa] (a=0,1,...5, “6+”)C N e M/2 F• Ca,t = Na,t e-M/2 Fa wa

12/6/06 13Kawai,…,Matsuda, Fish. Sci. 2002

Revised Management Procedurein International Whaling Commission

初期管理資源Initial stockquota

と生

産量

初期管理資源

持続的利用

Initial stock

Sustainable useCatc

h q

漁獲

圧と

保護対象

Sustainable useProtected stock

vit

y a

nd

0 1

漁

54%K KProducti

v

0 1相対資源量

Bayesian approach for measurement uncertainty

Relative stock size

KP

2006/5/22 14

Bayesian approach for measurement uncertainty

Yes it should have recoveredYes, it should have recovered. (Kawai et al 2002)

Actual stock abundance tons

)m

illio

n

stock if saving immature

mas

s (

ck b

iom

Sto

Probability that the stock recoversProbability that the stock recovers above 1 million tons (Kawai et al 2002)

百万トトン資源源回復確確率

We need another two decades for recovery

Management Strategy Evaluation(MSE)Simple version

0 61000

0 5

0.61000

t0.40.50.61000

ent

ass,

…

0.3

0.4

0.5

500 ffic

ient

ass,

har

vest

0.20.30.4

500

coeffic

ie

k bi

om

a

0.1

0.2

fish

ing

coe

stock

biom

00.1

00 50 sh

ing

c

stoc

year00

0 20 40 60

0 50 fisyear

year

A iti f l diAge composition of landings between Japan and north Atlantic

North Atlantic Fishery hasNorth Atlantic Fishery has IQ (individual quota)

Japan is still “Olympic” competition

ドーナツの内側から

North Atlantic2000-2004North Atlantic2000 2004

Japan 1970

Japan 1995

http://www.ices.dk/marineworld/fishmap/ices/pdf/mackerel.pdf

Ecosystem services V(N, C)

100120

ctio

n“Maximum Sustainable EcosystemServices” = maximizing V

V(N C) Y(C) + S(N) 406080

100生産力 s

prod

uMaximum Sustainable Yield= maximizing Y(C)

• V(N, C) = Y(C) + S(N) • N = K(1 – qE/r) 200 400 600 800 1000

2040

surp

lus

( q )• C = qEN

P i i l S i (Fi h i Yi ld) Y(C)

200 400 600 800 1000

親魚量Stock abundance

• Provisional Service (Fisheries Yield) … Y(C) • Utility of standing biomass… S(N)Utility of standing biomass… S(N) • C… catch; E… fishing effort; N… stock

bibiomass• K… Carrying capacity, r…Malthusian parameter, q…

t h bilit

Paradigm Shift from MSY to MSESParadigm Shift from MSY to MSES

M i S t i bl120

Maximum Sustainable Ecosystem Services

s

80

100 Maximum Sustainable Yield

serv

ices

vice

s

60

80

UnsustainableFi h i

stem

sYi

eld

ng S

erv

40No take zone

Fisheries e

cosy

sher

ies

egul

atin

20

Tota

l=

Fis

+ R

e

0

0 20 40 60 80 100 1202008/3/2 20Fishing effort

Catch and mean trophic level in Japan We can use >2 million tons of pelagic fi h t i bl i J EEZfishes sustainably in Japanese EEZ.

• But demand-supply mismatch: overfishing and underuse.pp y g

Source: Fisheries Research Agency, Japan

JC Castilla氏

Chile encourages artisanal fisheries

18009000

A1000

)

1000

) CHILE

○企業体漁業I

5 miles

1000

1200

1400

1600

5000

6000

7000

8000 AArtisan & Industrial (includes algae)IndustrialArtisan (includes algae)

FAL

c to

ns

1*

e ( U

S$

II

III

IVV

400

600

800

1000

2000

3000

4000

5000

ng (m

etric

ort

Valu

e

RMV

VIVII

VIIIIXX

1970 1975 1980 1985 1990 1995 2000 20050

200

0

1000

Land

in

Expo

XI

5 miles AEZ = Artisan Exclusive Zone (ca. 27.000 km2)

▼零細漁業XII

Territorial User Rights for Fishers (TURFs) are

ll t d t iti

•ＭＥＡＢＲｓ = Management and E l it ti A f

23

allocated to communities with MEABRs.

Exploitation Areas for Benthic Resources

Super-Malthusian Increase of populationand per capita energy consumption

World Population (0.1 billion)

Energy Consumption (1000kcal/day/person)

１

Year (A.D.)

Data: Earl Cook (1971) and Joel E. Cohen (1995)

Decreasing Ecological footprint,Increasing biological capacity with

WWF 2002

Increasing biological capacity with..ha

)Biodiversity conservation

rint (

gh Biodiversity conservation

Built-up landEnergyfo

otpr

gyFisheriesForestryGrasslandog

ical

GrasslandAgriculture

Ecol

o

Biologicalcarrying capacitycapacity

Ranking of per capita EFRanking of per capita EF

WWF Living Planet Report 2004

Global Ecological Footprinthttp://www.ecofoot.jp/

Our life step upon the size of 2 4 the Earth we have to goal2.4 the Earth, we have to goal

to size of one that.

WWF 2004

Measuring natural valueg（Costanza et al 1997)

•• ProvisioningProvisioning == agricultural fisheryagricultural fisheryProvisioningProvisioning = = agricultural, fishery agricultural, fishery and forestry products ca. 14 billion and forestry products ca. 14 billion

//yen/yearyen/year

•• RegulatingRegulating == material circulation camaterial circulation caRegulatingRegulating material circulation ca. material circulation ca. 170 billion yen/year170 billion yen/year

• Provisioning service << Regulating serviceservice

• Natural value of fishing ground > f f

28

compensation for fishers

biomePrice(US$/h )

area (km2)vaues(MUS$/ )

biome$/ha)

area (km2)(MUS$/year)

desert 0 215900 0tundra 0 43300 0I /R k 0 164000 0Ice/Rock 0 164000 0Open ocean 491 3320000 163,012marine shelf 2,222 266000 59,105

/ l d 2 871 441800 126 841grass/rangelands 2,871 441800 126,841

temperate/boreal forest 3,013 300300 90,480

lakes/rivers 4,267 20000 8,534a es/ ve s , 6 0000 8,53tropical forest 5,264 125800 66,221cropland 5,567 167200 93,080urban 6,661 35200 23,447, ,

swamps/flood plain 25,682 6000 15,409

tidal marsh/mangroves 193,845 12800 248,122

l f 352 249 2800 98 630

R. Costanza et al. / Global Environmental Change 26 (2014) 152–158

coral reefs 352,249 2800 98,630

Capture fisheries production in marine areasCapture fisheries production in marine areas（FAO, SOFIA2006)

• Landing is decreasing in Northwest Atlantic, but...

• It is increasing in Western Central Pacific!

• SOFIA 2014

Changes in the Marine Trophic Index

GBO2Pauly D., Watson R. Phil. Trans. R. Soc. B;2005;360:415-423

Difference in fish consumption b t t i

Total Fish Consumption (Metric Tons) Low Value Food Fish as a Share of Total FishConsumption

After Doug Beardbetween countries

120000

140000Consumption

80

90

80000

100000

Con

sum

ed

50

60

70

Developing World

40000

60000

ric T

ons

C

30

40

50

Perc

ent

Developed World

World

20000

40000

Met

r

10

20

30 World

01960 1980 2000 2020 2040

Year

01970 1980 1990 2000 2010 2020 2030

Year

From Delgado et. al. 2002, Fish to 2020, Table E.14

From Delgado et. al. 2002, Fish to 2020, Table 3.3

国際的に批判され始めた海洋栄養段階

Bi di it i di t id it l i d th t t f th l t

12月速報

Biodiversity indicators provide a vital window on the state of the planet, guiding policy development and management1,2. The most widely adopted marine indicator is mean trophic level (MTL) from catches, intended to detect shifts from high-trophic-level predators to low-trophic-intended to detect shifts from high trophic level predators to low trophiclevel invertebrates and plankton-feeders3–5. This indicator underpins reported trends in human impacts, declining when predators collapse (‘‘fishing down marine food webs’’)3 and when low-trophic-level fisheries

d (‘‘fi hi th h i f d b ’’)6 Th ti i th texpand (‘‘fishing through marine food webs’’)6. The assumption is that catch MTL measures changes in ecosystem MTL and biodiversity2,5. Here we combine model predictions with global assessments of MTL from catches trawl surveys and fisheries stock assessments7 and find thatcatches, trawl surveys and fisheries stock assessments7 and find that catch MTL does not reliably predict changes in marine ecosystems. Instead, catch MTL trends often diverge from ecosystem MTL trends obtained from surveys and assessments. In contrast to previous findings f id d li i t h MTL3 b t i i t hof rapid declines in catch MTL3, we observe recent increases in catch,

survey and assessment MTL. However, catches from most trophic levels are rising, which can intensify fishery collapses even when MTL trends are stable or increasing To detect fishing impacts on marine biodiversityare stable or increasing. To detect fishing impacts on marine biodiversity, we recommend greater efforts to measure true abundance trends for marine species, especially those most vulnerable to fishing. Adoption of an ecosystem approach to fisheries