contribution of fish2013

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Contribution of fisheriesand aquaculture to world food supply

Prof. Dr. Ulfert FockenThünen Institute of Fisheries Ecology, Ahrensburg BranchWulfsdorfer Weg 204, 22926 [email protected]

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Fish:Symbol for well-being and wealth in manycultures of the world

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Fish:Source of essential amino and fatty acids,especially important for the normal development of children with mainlyplant based diets

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Amino acids:

Tyrosine*

Serine*Taurine

Selenocysteine*Proline*Ornithine*ValineGlycineTryptophanGlutamine*ThreonineGlutamic acidPhenylalanineCysteine*MethionineAspartic acidLysineAsparagineLeucineArginine*IsoleucineAlanineHistidineNonessentialEssential

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Essential fatty acids:

alpha-linolenic acid (ALA)

eicosapentaenoic acid (EPA)

docosahexaenoic acid (DHA)

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Essential fatty acids:Both, fish and men, have a limitted capacityto transform ω-3 fatty acids by elongationand desaturation

alpha-linolenic acid (ALA)

eicosapentaenoic acid (EPA)

docosahexaenoic acid (DHA)

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LC-PUFA:Especially important for the braindevelopment, malnutrition in the first 1000 days (pregnancy and first 2 years) results in irriversible limitation of cognitive capacity

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LC-PUFA:In adults, long chain ω-3 fatty acids areimportant in the prevention of cardio-vascular diseases and may also play a role in the development of neurodegenerative diseases (Alzheimer, Parkinson)

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ω-6 fatty acids:Precursors of numerous metabolic activesubstances, Excess probably negative for health

Arachidonic acid

Linolenic acid

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Fish:Worldwide, fish provides 17% of animal protein in human nutrition.Asia: 26%Africa: 17%South America 7%Europe, Former USSR 9%N&C America 7%

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100100Total protein

5959Animalprotein

44Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesGermany 2003

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100108Total protein

6065Animalprotein


% of total protein


Fish in the diet in selected countriesNorway 2003

15

10056Total protein

2715Animalprotein


% of total protein


Fish in the diet in selected countriesGhana 2003

16

10055Total protein

74Animalprotein


% of total protein


Fish in the diet in selected countriesMalawi 2003

17

10047Total protein

126Animalprotein


% of total protein


Fish in the diet in selected countriesBangladesh 2003

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10082Total protein

4033Animalprotein


% of total protein


Fish in the diet in selected countriesChina 2003

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10056Total protein

4324Animalprotein


% of total protein


Fish in the diet in selected countriesThailand 2003

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10085Total protein

4942Animalprotein


% of total protein


Fish in the diet in selected countriesBrasil 2003

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10067Total protein

3725Animalprotein


% of total protein


Fish in the diet in selected countriesPeru 2003

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Statistical data are very likely to underestimate fish production and consumption in rural areas due to fish that is not marketed, but eithercaught or produced for homeconsumption.

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Fish is not all the same.

Lean freshwater fish - tilapiaLipid-rich freshwater fish - carp

Lean marine fish – sea bassLipid-rich marine fish – salmon, mackarel, sardines ...

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Fish is not all the same

Fish in which mostly the filet isconsumed

Fish which are consumed entirely, deep-fried, as sauce, as fish curry- Very high contribution to mineral and vitamin a supply (Roos et al. 2002, 2003, 2007)

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1970ies:Give a person a fish, and he will have food for a day.Teach him to catch fish, and he will havefood for a life time.

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Fish as food:Sources: - Capture Fisheries

(equivalent to hunting)

- Aquaculture(equivalent to animal production)

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Yield of Capture Fisheries

1950 1960 1970 1980 1990 20000

50

100

150

Capture

Year

Wor

ld F

ish

Yiel

ds(M

illio

n m

etric

tons

)

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Trawling for herring in the North Sea

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Estimated Sustainable Yields

1970 200 million metric tons

1990 130 million metric tons

2002 >> 100 million metric tons ???

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Fish Catch (per Unit of Effort)Linear Function of Biomass

0.00 0.25 0.50 0.75 1.000.0

0.2

0.4

0.6

0.8

1.0

Biomass

Cat

ch p

er U

nit o

f Effo

rt(a

s fr

actio

n of

max

imum

)

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Fish Catch- Yield (Surplus Production)- Reduction of Stock

Fish YieldInverted Parabolic Function ofFish Biomass

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Capture Fisheries:Yield versus Biomass

0.00 0.25 0.50 0.75 1.000.0

2.5

5.0

7.5

10.0MSY

Biomass

Yiel

d(a

s pe

rcen

t of b

iom

ass)

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Capture Fisheries:Yield versus Fishing Effort

0.00 0.25 0.50 0.75 1.000.0

2.5

5.0

7.5

10.0MSY

Biomass

Yiel

d(a

s pe

rcen

t of b

iom

ass)

Fishing Effort

0.0∞

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Problems in Fisheries Management:- General Problems of Commun Property Resources- Specific Problems - Resource is not directly visible - Resource may extend over or migrate within the area of several administrative units

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High Fish Yields do not Garantee Food Supply

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High Fish Yields do not Garantee Food SupplyFish Production and Consumption

in Peru 1970 to 1999

1970 1980 1990 20000

5000

10000

ProductionExportConsumtion

0

5

10

15

20

25

Year

Fish

Pro

duct

ion/

Expo

rt(1

000

met

ric to

ns) Fish Protein Cons.

per caput per day (g)

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Contribution of capture fisheriesto food security

- more limitted by lack of appropriatemanagement than by ability to catch fish

- fish may be unavailable to domesticpopulation

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Aquaculture- Definition by FAO:"The husbandry of aquatic organismslike finfish, mollusc, crustaceans and sea weeds under individual orcorporate ownership."

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1950 1960 1970 1980 1990 2000 20100

2×100 7

4×100 7

6×100 7

OtherOceaniaAfricaAmericas

Asia

Europe

Year

Aqua

cultu

re P

rodu

ctio

n t

(exc

ludi

ng s

eaw

eeds

)

60 x 106

20 x 106

40 x 106

World Aquaculture Production

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Aquaculture systems:

Intensive Systems

Semi-Intensive Systems

Extensive Systems

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Intensive Aquaculture Systems:

Growth of cultured organisms dependsexclusively on compond fed, typicallywith high content of fish meal and fishoil.

Feed conversion ratio 3:1 - 10:1Product typically expensiveEnvironmental impact high

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Intensive Aquaculture Systems (2):

High demand for fossil energyHigh input for prophylaxis and therapyof diseases and parasites

Examples:Salmon, troutCatfisch, Tilapia in the USAShrimp

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Intensive Shrimp-Culture

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Extensive Aquaculture Systems:

Growth depends only on naturalproductivity, no feeding etc.

Product typically cheap(exception oystersLow environmental impact,High demand for area

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Extensive Aquaculture Systems (2):

Examples:Mussel and oyster cultureUtilization of temporal water bodies

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Semi-Intensive Aquaculture Systems:

Growth of fish depends on natural food, which is enhanced by fertilization orsupplemented by limited feeding.

Product: mainly cheapEnvironmental impact typically low, butpulsed

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Semi-Intensive Aquaculture Systems (2):

Examples:Carp production in EuropeTilapia-Production in the Tropics

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Semi-intensive milkfish culture

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Semi-Intensive Aquaculture Systems (3):

Especially efficient are aquaculture systems integrated with animal production,e.g. poultry-fish, pig-fish.Without direct feeding of fish, yields of severaltons per hectare and year are possible.

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Aquaculture Production and Food Supply inSome Asian Countries

Thailand

1970 1975 1980 1985 1990 1995 2000

0250

500750

05

1015

2025

Year

Aquaculture Production(thousand m

etric tons) Fish

Pro

tein

Con

s.pe

r ca

put p

er d

ay (g

)

62


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Year BrackishwaterProduction (t)

Pond Area(ha)

Yield(kg*ha-1*a-

1)1955 36700 105000 3501975 106500 176000 6051980 136000 176000 7711985 155300 160000 9691990 191900 150000 12791995 137800 112500 1225

Brackish water production of milkfishin the Philippines 1955 - 1995

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The contribution of aquaculture to domesticfood supply largely depends on theaquaculture system used.The export of aquaculture products is a major source of export revenew in severalcountries and a source of employment and income in coastal and rural areas.

contribution of fish2013

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