1 Optimal fishing policies that maximize sustainable ecosystem services Hiroyuki Matsuda (Yokohama Nat’l U), Mitsutaku Makino (Jpn Fish Agency) Koji Kotani

1

Optimal fishing policies that maximize sustainable ecosystem services

Hiroyuki Matsuda (Yokohama Nat’l U),

Mitsutaku Makino (Jpn Fish Agency)

Koji Kotani (International Univ of Jpn)

2

Overview

Requiem to Maximum Sustainable Yield theory Adaptive management is useful for uncert

ain, dynamic stocks, but… Yield is a small part of ecosystem services MS Ecosystem Services is more prudent a

nd enhance biodiversity To ecosystem comanagement Comprehensive indicator of biodiversitya

3

Requiem to Maximum Sustainable Yield Theory

Ecosystems are uncertain, non-equilibrium and complex.

MSY theory ignores all the three. Does MSY theory

guarantee species persistence?- No!!

Stock abundance

surp

lus p

rodu

ctio

n

4

Unconstrained MSY that maximizes the total yield from the community

(Matsuda & Abrams 2006 Ecol Appl)

dN/dt = (r – C.N – e)N, Y = e.(pN – c) We choose fishing effort ei independent

ly; 6-species systems including 2 prey random matrix with 50% probabilities; we seek r having a positive equilibrium; price p is 0-1 for prey, 0-10 for predator

s

5

2

54

3

5

3

6

4

4

Examples of biological community at MSY (Matsuda & Abrams 2006 　 Ecol. Appl.)

1 2

3

5

6

(b)

1 2

3

5

6

4

(a)

1 2

5

(c)

3

6

4

Solution maximizing total yield from community

MSY solution often reduces species and links;

1 2

6

4

(d)

1

3

6

(e)

2

54

3

54

6

Conclusion of MSY from food web

MSY theory does not guarantee species coexistence

Fisheries must take care of biodiversity conservation explicitly

= Foodweb constraint to reconciling fisheries with conservation

e.g., Consider ecosystem services!

7

Overview

Requiem to MS Yield theory Adaptive management is useful for uncert


nd enhance biodiversity To ecosystem comanagement Comprehensive indicator of biodiversity

8

Rules of fishing effort that depend on the estimate of stock abundance

0

0.2

0.4

0.6

0.8

1

0 200 400 600 800 1000 1200Estimate of stock abundance N

Fis

hin

g m

ort

alit

y F

ABC rule

Constant catch

Constant escapement

9

Merits of adaptive stock management

Constant harvest (CH) amount will drive stock collapse, even CH ratio too

Constant escapement results in a huge variation of catch and vulnerable to stock measurement errors.

Adaptive management (“ABC rule”) results in more stable catch, is robust against measurement & process errors.

10

If prey is exploited and fishing effort is feedback control, ...(Matsuda & Abrams

in prep.)

no adaptation (C is constant)dE/dt = U(N-N*)

1bfCN

hCNdP d gP Pdt

dN/dt=0dP/dt=0

sardine N

predator P fishery E

11

dN r N P qCENdt

fCNNK hCN

N

P

11

Toward ecosystem approach

Single stock monitoring is dangerous Target stock level is much more sensitive

than we have considered in single stock models.

We must monitor not only stock level of target species, but also the “entire” ecosystem.

12

Overview




132006/5/22 13

Ecosystem services and well-being（MA2005)

14

Ecosystem Services and Natural Capital

Goods (Resource of Agriculture etc.)Goods (Resource of Agriculture etc.) Ecosystem services (Air, Water)Ecosystem services (Air, Water) Amenity, and intrinsic values are estiAmenity, and intrinsic values are esti

mated to be in US$16-54 trillion per mated to be in US$16-54 trillion per year, most of which is outside the mayear, most of which is outside the market rket

15

Overview




16

Ecosystem services V(N, C)

2008/3/2 16

V(N, C) = Y(C) – cE + S(N)

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

ass

17

Stock abundance N

Regulating services S(N)= SN2/(B2+N2)

(S, B) = (100,10)

(S, B) = (50,50)

2008/3/2 17

18

Mathematics Stock dynamics … dN/dt = (r – aN)N – C, Catch and yield … C = qEN, Y(C) = pqEN, Regulating service … S(N) = SN2/(B2+N2), Equilibrium … N*(E) = (r – qE)/a Service at N* … V*(E) = pqEN* – cE + S(N*) Optimal effort Eopt satisfies that V*/E = 0 Maximum Sustainable Ecosystem Service

Eopt = (pqr – ac)/2pq2

2008/3/2 18

19Fishing effort E

Maximum Sustainable Ecosystem Service

(S, B) = (100,10)

(S, B) = (50,50)

(S, B) = (0,-)

2008/3/2 19

Stock abundance N

200

500

1000

0 10 20 30 40 50 60 70

Sto

ck N

an

d c

atc

h C

0

0.2

0.4

0.6

fish

ing

eff

ort

E

MSY vs MSES with process uncertainties

0

500

1000

0 10 20 30 40 50 60 70

Sto

ck N

an

d c

atc

h C

0

0.2

0.4

0.6

fish

ing

eff

ort

E

MSY

MSES

year

21

MSES from food webs

Community dynamics …dNi/dt = (ri + ajiNj – qiEi)Ni

Yield from foodweb… Y(E) = Ei(piqiNi – ci)

Total ecosystem services...V(E) = Y(E) + Si(Ni)

Si(Ni) = SiNi

2/(Bi2+Ni

2)

We obtained EMSES ↑ Y(E) and EMSY ↑V(E)

2008/3/2 21

22

2

5

3

4

6

1

2

5

3

4

6

1

3

2

5

4

6

1

3

4 15 30

2

5

4

6

1

3

(a) (b)

(e)

1 2

5

3

4

6

(d)

5

4

6

3

1 2

(c)

1 2

5

3

4

6 5

(h)

56

3

1 2

4

(g)(f)

2008/3/2 22

23

Resultant food webs and fishing efforts from 1000 randomly constructed six species systems

No. of species

No. of extant species using MSY policy

No. of exploited

species using MSY policy

No of extant species using MSES policy

No of exploited species using MSES policy

0 0 0 0 9

1 0 204 0 96

2 206 792 13 318

3 531 4 43 337

4 236 0 31 201

5 25 0 8 35

6 2 0 905 4

24

MSES saves fishing efforts

2008/3/2 24

Ban-on-Fishing

25

Overview




26

1. The objectives … are a matter of societal choice.2. Management should be decentralized to the lowest …level. 3. ... managers should consider …adjacent …ecosystems. 4. … usually …manage …in an economic context. Any such ecosystem-management programme should: 5. Conservation of ecosystem structure and functioning… shoul

d be a priority target of the ecosystem approach. 6. Ecosystem …managed within the limits of their functioning.7. … undertaken at the appropriate spatial and temporal scales. 8. Recognizing the varying temporal scales and lag-effects…,

objectives …should be set for the long term. 9. Management must recognize the change is inevitable. 10. The ecosystem approach should seek the appropriate balance

between… conservation and use of biological diversity. 11. …should consider all…, including scientific and indigenous

and local knowledge, innovations and practices. 12. …involve all relevant sectors of society and …disciplines.

12 Principles of Ecosystem Approach of CBD

The Ecosystem Approach is a social strategy that links biological, social and economic information, and aims to achieve a socially acceptable balance between nature conservation and the use and sharing of benefits from ecosystems.

27

Fishers can monitor “their” marine ecosystem

Monitoring activities are critically important to increase the yield Y(E) and to sustain the utility of standing biomass S(N). Government should play an important role in these monitoring activities. However, in reality, it is almost impossible for the government to monitor all the detailed ecosystems along the coast and within exclusive economic zones (EEZ). Therefore, the knowledge of fishers and data from fishery activities should be fully utilized.

2828

Most of keystone species are caught and recorded by local

fishers org.s!Sustainable fisheries play

roles of “umbrella species” like top predators!

Coastal Foodweb at Shiretoko Heritage

Draft food web by SC

2929

Fisheries catch statistics in Shiretoko Area

tons

Very informative time-series data for monitoring the changes in ecosystem structure/functions

Made by Mitsutaku Makino

30

Reality of MSES Our analyses also indicate that yield-maximizing

fisheries would invoke the loss of a significant fraction of species in the web. It will inevitably lead to the degradation of S(N), and easily set off the benefit from Y(C), and ultimately reduce the total ecosystem services, V(E).

To avoid these situations, government has to monitor the rest of the ecosystem, and regulate the yield-maximizing fisheries in a top-down way. The reality is, again, these costs would be beyond the budget of many countries, especially developing countries. To sum up the above discussions, yield-maximizing, economically-efficient fisheries are rational for enjoying fishery rent, but not always so in sustaining total ecosystem services for society.

31

Fishers’ knowledge may sustain ecosystems

From the viewpoint of sustaining ecosystem services, we encourage responsible fisheries targets for a wide range of species with a variety of gear.

Local fishers often have accumulated the catch data of these species for over 50 years. Responsible fisheries can significantly contribute to the sustainability of ecosystem services if we evaluate the catch data.

A fisheries management approach in which government and local fishers share the responsibilities and authorities for the use of sustainable resource is called fisheries comanagement, the strongest argument against the conventional top-down approach (Makino and Matsuda 2005).

32

Forestation activities by local people (http://www.jf-net.ne.jp/hkyubetsu/sigen.htm)

Local legend says

“Forests are the roots of coastal fish”(http://www.jf-net.ne.jp/amhiranaigyokyo/)

Voluntary Activities (1)

3333

Spawning ground

Since 2005

Bottom trawling is totally prohibited in the coastal area

R1: Voluntary regulation of walleye pollock

177 boats fished walleye pollock in 1995Decreased to 86 boats in 2004 (49% reduction)

– Compensation to retired fishers by Fisheries Organization

Fishing ban during Mar 20-end since 1995Fishing ban area expanded in 2005 Since 1995

34

Role of the government

To avoid these situations, government has to monitor the rest of the ecosystem, and adaptively regulate the yield-maximizing (i.e. commercial) fisheries, often in a top-down way.

The reality is, these costs would be beyond the budget of many countries, esp. developing countries.

35

From fisheries comanagement to ecosystem comanagement

Fisheries comanagement will not always lead to the ecosystem management: It is likely that VMSES > VMSY and EMSES < EMSY

In order to increase the total ecosystem services, interests from other sectors than fisheries, such as an environmental ministry or non-government organizations (NGOs), should be included in the decision-making arena (Makino 2005).

36

Overview




37

Convention on Biological Diversity (CBD) CoP10, Nagoya, Japan, 2010

CBD CoP10 is important because of the 2010 Biodiversity Target (CoP6). Host nation Japan must keep leadership of further goals.

“Parties commit themselves to […] achieve by 2010 a significant reduction of the current rate of biodiversity loss.”

I expect Ministry of Environment to make Comprehensive Environmental Assessment with indicators

38

Draft framework of marine biodiversity by Matsuda

DP1:Fisheries & exploitation• Overfishing• By-catach• Aquaculture• Bottom trawling• Catch of marine mammals

Driving forces/Pressures State/Impacts Response

DP2 Civil engineering• Fluvial sediment• Reclamation, artificial

shore and breakwater• Gravel dipping

SI1 Loss of species richness• Mean trophic levels• Fish stock biomass• Mammals, birds & turtles

R1 Sustainable use• Catch regulation• Ecolabels• Stock rehabilitation p

rogram

SI2 Habitat loss/degradation• Sand beach• Sea grass/weed beds• Tidal flat• Coral reefs

DP3 Pollution and debris• Eutrophication• Oil spilling• Exotic species• Chemicals (TBT)

SI3 Material cycling• Red tide, blue tide• Imposex of snails

R2 MPAs by• International MPAs• National parks• Voluntary MPAs• Nature restoration pro

jects

R3 Env. regulations• Env. Impact Assess.• BOD emissions• TBT regulationSI4 Genetic pollution

• SalmonidsDP4 Climate change• Global warming• pH decrease

39

DP3 Exotic marine species

40

DP3: PCDDs, PCDFs and Co-PCBs in Tokyo Bay: Sources and Contribution,

41

SI1: Fishing down (MA 2005)

In Japan??? F-MAP’s mission?

42

SI1: Catch and mean trophic levels in Japan

Fishing ground changed decadally.

430

10

20

30

40

50

60

70

80

1997 1998 1999 2000 2001 2002 2003

TAC

AB

CC

atch

1000

0ton

s，

，（

）マイワシ

SI1: trend in catch and stock of Red Sea Bream and Japanese sardine

Stock (1000 tons)

Harvest rate

CatchCatch of wild larvaeSeed release

Stoc

k (1

000

tons

)

Har

vest

rat

e

Caa

tch

(100

0 to

ns)

No.

indi

vudu

als

(10,

000)

Red Sea Bream (West Sea of Japan/Southeast China Sea)

Stoc

k (1

000

tons

)

Har

vest

rat

e

Stock (1000 tons) Harvest rate

Japanese sardine (Pacific stock)Japanese sardine (total)

ABCTACCatch

http://abchan.job.affrc.go.jp/digests20/index.html

44

SI2: Reduction of sea grass/weed bed in Seto Inland Sea

45

SI2: Trend and volume of suspended load

要引用許可

105 m3

104 m3

103 m3

>1m increase

>1m decrease

www.nilim.go.jp/lab/dbg/pdf/200806_fac.pdf

46

SI3: Imposex of Babylonia japonica by TBT/TPT （ Horiguchi et al 2006 Env Health Pers ）

Fecundity (g) of cultured B. japonica Release of B. japonica juveniles (105 ind.)Catch (tons)

Horiguchi, T., Kojima, M., Hamada, F., Kajikawa, A., Shiraishi, H., Morita, M., Shimizu, M.: Impact of tributyltin and triphenyltin on ivory shell (Babylonia japonica) populations. Environ. Health Perspectives 114: 13-19, 2006.

Babylonia japonica

4747

Spawning ground

Since 2005

Bottom trawling is totally prohibited in the coastal area

R1: Voluntary regulation of walleye pollock

177 boats fished walleye pollock in 1995Decreased to 86 boats in 2004 (49% reduction)

– Compensation to retired fishers by Fisheries Organization

Fishing ban during Mar 20-end since 1995Fishing ban area expanded in 2005 Since 1995

48

R1: The number of registered MSCs in the World and Japan

WorldJapan

49

R2: MPA Construction to protect spawning/breeding area (by public

expenses)

(Sited from Kyoto Institute of Oceanic and Fishery Science HP)

牧野光琢氏

2　図京都府沖合海域における各施策の経年変化

0

20

40

60

80

100

120

67 69 71 73 75 77 79 81 83 85 87 89 91 93 95 97 99年度

Phase1 Phase4Phase3Phase2

MPA Construction (km2)

Temporal Fishing Ban(%)

Fiscal Year

50

R2:Sandfish fishery mgmt at Akita Pref.

Mgmt Method: -Complete ban of fishing for

three years (Sep. ’92 – Aug. ’97)

-Minimum size limit-Annual catch limit-Gear, ground and season limit-Restoration of breeding

ground-Fish seeds release -pooling system of fishery

income

Mapmap Ver.6.0

www.pref.akita.jp

Arctoscopus japonicusMgmt actors:Local fishermen,Local research station, etc.

Cat

ch (

tons

)

51

Conclusion

Responsible fisheries may play roles of umbrella species that use a small part of healthy ecosystem services, and give many data of utilized resources…

Fishing efforts that maximizes the total ecosystem services are usually much smaller than those for maximum sustainable yield.

2008/3/2 51

52

Abstract Classic theory seeks MSY from target species

ignores uncertainty, fluctuation, species interactions.

MSY do not guarantee coexistence of species. Ecosystems provide supporting, provisioning (

fisheries yields), regulating, and cultural services.

The stock biomass maintains these services, and regulating services >> fishery yields.

We define maximum ecosystem service (MSES) in a single species model with and without uncertainties and in multiple species models.

In any case, fishing efforts for MSES are usually much smaller than those for MSY.

53

Overview




54

Overview




55

Regulating services S(N)= SN2/(B2+N2)

(S, B) = (100,10)

(S, B) = (50,50)

2008/3/2 55

Stock abundance N

Unsustainable　Fisheries

Maximum　Sustainable　Yield

No　take　zone

Documents

1 Optimal fishing policies that maximize sustainable ecosystem services Hiroyuki Matsuda (Yokohama Nat’l U), Mitsutaku Makino (Jpn Fish Agency) Koji Kotani