Contribution of fish2013

1

Contribution of fisheriesand aquaculture to world food supply

Prof. Dr. Ulfert FockenThünen Institute of Fisheries Ecology, Ahrensburg BranchWulfsdorfer Weg 204, 22926 Ahrensburgulfert.focken@ti.bund.de

2

3

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

4

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

5

Amino acids:

Tyrosine*

Serine*Taurine

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

6

Essential fatty acids:

alpha-linolenic acid (ALA)

eicosapentaenoic acid (EPA)

docosahexaenoic acid (DHA)

7

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)

8

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

9

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)

10

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

Arachidonic acid

Linolenic acid

11

12

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%

13

100100Total protein

5959Animalprotein

44Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesGermany 2003

14

100108Total protein

6065Animalprotein

1617Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesNorway 2003

15

10056Total protein

2715Animalprotein

169Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesGhana 2003

16

10055Total protein

74Animalprotein

21Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesMalawi 2003

17

10047Total protein

126Animalprotein

63Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesBangladesh 2003

18

10082Total protein

4033Animalprotein

76Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesChina 2003

19

10056Total protein

4324Animalprotein

1810Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesThailand 2003

20

10085Total protein

4942Animalprotein

22Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesBrasil 2003

21

10067Total protein

3725Animalprotein

96Fish and seafruits

% of total protein

g protein/ capita/day

Fish in the diet in selected countriesPeru 2003

22

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.

23

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 ...

24

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)

25

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.

26

Fish as food:Sources: - Capture Fisheries

(equivalent to hunting)

- Aquaculture(equivalent to animal production)

27

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

)

28

Trawling for herring in the North Sea

29

Estimated Sustainable Yields

1970 200 million metric tons

1990 130 million metric tons

2002 >> 100 million metric tons ???

30

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

)

31

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

Fish YieldInverted Parabolic Function ofFish Biomass

32

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)

33

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∞

34

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

35

High Fish Yields do not Garantee Food Supply

36

37

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)

38

Contribution of capture fisheriesto food security

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

- fish may be unavailable to domesticpopulation

39

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

40

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

41

Aquaculture systems:

Intensive Systems

Semi-Intensive Systems

Extensive Systems

42

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

43

Intensive Aquaculture Systems (2):

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

Examples:Salmon, troutCatfisch, Tilapia in the USAShrimp

44

45

46

47

Intensive Shrimp-Culture

48

Extensive Aquaculture Systems:

Growth depends only on naturalproductivity, no feeding etc.

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

49

Extensive Aquaculture Systems (2):

Examples:Mussel and oyster cultureUtilization of temporal water bodies

50

51

52

53

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

54

55

Semi-Intensive Aquaculture Systems (2):

Examples:Carp production in EuropeTilapia-Production in the Tropics

56

Semi-intensive milkfish culture

57

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.

58

59

60

61

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

Aquaculture Production and Food Supply inSome Asian Countries

63

64

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

65

Aquaculture Production and Food Supply inSome Asian Countries

66

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.