THE EVOLUTION OF INTEGRATED SEAWEEDCULTIVATION IN TEMPERATE SOUTHERNAFRICA
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Transcript of THE EVOLUTION OF INTEGRATED SEAWEEDCULTIVATION IN TEMPERATE SOUTHERNAFRICA
THE EVOLUTION OF INTEGRATED THE EVOLUTION OF INTEGRATED SEAWEEDSEAWEEDCULTIVATION IN TEMPERATE SOUTHERNCULTIVATION IN TEMPERATE SOUTHERNAFRICAAFRICA
THE EVOLUTION OF INTEGRATED THE EVOLUTION OF INTEGRATED SEAWEEDSEAWEEDCULTIVATION IN TEMPERATE SOUTHERNCULTIVATION IN TEMPERATE SOUTHERNAFRICAAFRICA
Robertson-Andersson Deborah1; J. J. Bolton1, M. Troell2,3, R. J. Anderson4, G. Maneveldt5, C. Halling2, A. J. Smit6, T. Probyn7 & S. Peall8
1Botany Department, UCT2Department of Systems Ecology, Stockholm University
3Beijer Institute, Stockholm, Sweden
4Seaweed Research Unit, MCM 5Botany Department, UWC
6School of Biological and Conservation Sciences, UKZN 7Aquaculture Unit, MCM
8Hearshaw and Kinnes Laboratory, UCT
Robertson-Andersson Deborah1; J. J. Bolton1, M. Troell2,3, R. J. Anderson4, G. Maneveldt5, C. Halling2, A. J. Smit6, T. Probyn7 & S. Peall8
1Botany Department, UCT2Department of Systems Ecology, Stockholm University
3Beijer Institute, Stockholm, Sweden
4Seaweed Research Unit, MCM 5Botany Department, UWC
6School of Biological and Conservation Sciences, UKZN 7Aquaculture Unit, MCM
8Hearshaw and Kinnes Laboratory, UCT
What phycologist’s love to do at an What phycologist’s love to do at an ISS…ISS…What phycologist’s love to do at an What phycologist’s love to do at an ISS…ISS…
Scenes from the symposium…Scenes from the symposium…Scenes from the symposium…Scenes from the symposium…
The Nori growing processThe Nori growing processThe Nori growing processThe Nori growing process
A Nori processing plantA Nori processing plantA Nori processing plantA Nori processing plant
THE EVOLUTION OF INTEGRATED THE EVOLUTION OF INTEGRATED SEAWEEDSEAWEEDCULTIVATION IN TEMPERATE SOUTHERNCULTIVATION IN TEMPERATE SOUTHERNAFRICAAFRICA
THE EVOLUTION OF INTEGRATED THE EVOLUTION OF INTEGRATED SEAWEEDSEAWEEDCULTIVATION IN TEMPERATE SOUTHERNCULTIVATION IN TEMPERATE SOUTHERNAFRICAAFRICA
Robertson-Andersson Deborah1; J. J. Bolton1, M. Troell2,3, R. J. Anderson4, G. Maneveldt5, C. Halling2, A. J. Smit6, T. Probyn7 & S. Peall8
1Botany Department, UCT2Department of Systems Ecology, Stockholm University
3Beijer Institute, Stockholm, Sweden
4Seaweed Research Unit, MCM 5Botany Department, UWC
6School of Biological and Conservation Sciences, UKZN 7Aquaculture Unit, MCM
8Hearshaw and Kinnes Laboratory, UCT
Robertson-Andersson Deborah1; J. J. Bolton1, M. Troell2,3, R. J. Anderson4, G. Maneveldt5, C. Halling2, A. J. Smit6, T. Probyn7 & S. Peall8
1Botany Department, UCT2Department of Systems Ecology, Stockholm University
3Beijer Institute, Stockholm, Sweden
4Seaweed Research Unit, MCM 5Botany Department, UWC
6School of Biological and Conservation Sciences, UKZN 7Aquaculture Unit, MCM
8Hearshaw and Kinnes Laboratory, UCT
OverviewOverview
An overview on the development of seaweed aquaculture in
temperate Southern Africa.
The current drivers for integrated seaweed aquaculture.
An integrated abalone seaweed system.
Economic benefits & inter-linkages abalone farming and seaweed
cultivation.
Socio-economic effects and multiplier effects.
Seaweed utilization history: Seaweed utilization history: South AfricaSouth Africa
& Namibia& Namibia
Southern Africa has a recent history of seaweed utilization.
Beach cast harvest started in the 1940’s.
Driver - Shortages of algal based colloids caused by WWII.
Gelidium picking on South African east coast
Kelp harvesting on South African south and west coastsREFS: Isacs 1942, 1953
Anderson et al. 1989
REFS: Isacs 1942, 1953Anderson et al. 1989
Seaweed utilization history: Seaweed utilization history: NamibiaNamibia
Seaweed cultivation first started in Radford bay, Lüderitz Namibia in the
1980’s.
Cultivation of Gracilaria gracilis occurred in 4 - land based, semi-inter-tidal
ponds.
By fertilizing with urea, they obtained a 10 fold increase in production over a
90 day period.
Driver - Commercial production of Gracilaria for agar to supplement
beach cast harvests.
Pictures from Google EarthPictures from Google Earth
REFS: Rotmann 1987Anderson et al. 1989, 2003
REFS: Rotmann 1987Anderson et al. 1989, 2003
Seaweed utilization history: Seaweed utilization history: NamibiaNamibia
Moved to pump ashore ponds then…
In Lüderitz Bay, rope raft cultivation of G. gracilis was started in the 1990’s.
Production was 80 t y-1 in a 4 hectare area.
Driver - High pumping and other capital costs of pond cultivation.
G. Gracilis being threaded onto “Netlon”
Rope rafts in Lüderitz Bay Harvested using traditionalfishing boats REFS: Anderson et al. 1989, 2003
Dawes, 1985REFS: Anderson et al. 1989, 2003
Dawes, 1985
Seaweed utilization history: Seaweed utilization history: South South AfricaAfrica
Seaweed cultivation on an experimental scale first started in Saldanha Bay in the
1990’s using methods adapted from Namibia with G. gracilis.
Cultivation was successful and there was evidence of integration, with fish factory
wastes being taken up by the Gracilaria.
Driver - Disappearance of G. gracilis wash-ups due to natural and
anthropomorphic events.
Medium to small beach wash up
1970’s – 1980’s
Little to no wash up
Present dayREFS: Anderson et al. 1989, 2003REFS: Anderson et al. 1989, 2003
Seaweed utilization history: Seaweed utilization history: South South AfricaAfrica
SGR was 5 % d–1, and a yield of 39.6 t.d.wt.ha–1y–1.
Commercial production did occur twice and experimental cultivation
also occurred in St Helena bay.
Failures due to - Thermal stratification in the bay during summer resulting in a
lack of nutrients available to the seaweeds and high
temperatures.
Fouling by mussels and tunicates.
H2S killing all seaweeds following die off of algal blooms.
Final harvestExperimental raftMonitoring of linesREFS: Anderson et al. 1989, 2003REFS: Anderson et al. 1989, 2003
0
100
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1957
1960
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2002
Years
Ab
alo
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(to
ns
)
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Ab
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d b
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(to
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)
Abalone production WW Kelp as abalone feed WW
beach cast DW
Seaweed utilization history: Seaweed utilization history: South South AfricaAfrica
In the 1990’s abalone farming started using Haliotis midae.
Ecklonia maxima was used as a feed source for farms on the
western and South west cape coasts.
Driver for seaweed cultivation on land - Lack of and decrease in kelp
resource to feed increasing industry.
Kelp concession areas being harvested at 60 – 99 % of their MSY.
Kelp harvest vs. kelp demand as abalone feed
Position of abalone farms round coast line
Seaweed cultivation history: Seaweed cultivation history: Eastern Eastern CapeCape
From 1992 to present, 25 Masters and Honors projects looked
at land based cultivation of seaweeds. Most looked at
cultivation in flow- through systems, utilizing a variety of
species.
In 2000, 2 farms in the eastern cape built a total of 34 paddle
ponds cultivating Ulva and G. gracilis based on this research.
Driver - Food source for abalone - high seawater
temperatures cause artificial feed to ferment and bloat
abalone.
Kelp doesn’t grow in the eastern cape.
Paddle ponds on a flow through system
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Aug-02
Sep-0
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03
Feb-0
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Mar
-03
Apr-03
May
-03
Mea
n w
et w
eig
ht
(g)
Mixed diet
Rotation
Fresh Kelp
Fresh Kelp + formulated feed
Formulated feed
In 2000 research on 2 abalone farms in the western cape looked at the
use of seaweeds as biofilters and a feed source. Ultimately to develop
an integrated abalone seaweed system.
Drivers – Lack of and decrease in kelp resource to feed increasing industry.
Mixed diets are known to give better growth
rates.
Potential over-harvesting and decrease in
epiphyte densities on kelp after harvesting.
Limited suitable coastal areas for open ocean
cultivation.
Recirculation – protection from ‘HAB’s’ = 33 %
loss in profits for 1 year.
Seaweed cultivation history: Seaweed cultivation history: Western Western CapeCape
Effect of diets on abalone growth rates
Naidoo et al. 2006Naidoo et al. 2006
Seaweed cultivation history: Seaweed cultivation history: Western Western CapeCape
Effect of harvesting on regrowth of obligate epiphytes on kelp
0
0.5
1
1.5
2
2.5
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3.5
Control harvest
g ep
iphy
tes/
kg o
f kel
p
In 2000 research on 2 abalone farms in the western cape looked at the
use of seaweeds as biofilters and a feed source. Ultimately to develop
an integrated abalone seaweed system.
Drivers – Lack of and decrease in kelp resource to feed increasing industry.
Mixed diets are known to give better growth
rates.
Potential over-harvesting and decrease in
epiphyte densities on kelp after harvesting.
Limited suitable coastal areas for open ocean
cultivation.
Recirculation – protection from ‘HAB’s’ = 33 %
loss in profits for 1 year.
Anderson et al. 2006Anderson et al. 2006
Seaweed cultivation history: Seaweed cultivation history: Western Western CapeCape
Red tide moving towards abalone intake
In 2000 research on 2 abalone farms in the western cape looked at the
use of seaweeds as biofilters and a feed source. Ultimately to develop
an integrated abalone seaweed system.
Drivers – Lack of and decrease in kelp resource to feed increasing industry.
Mixed diets are known to give better growth
rates.
Potential over-harvesting and decrease in
epiphyte densities on kelp after harvesting.
Limited suitable coastal areas for open ocean
cultivation.
Recirculation – protection from ‘HAB’s’ = 33 %
loss in profits for 1 year.
The aims of this research were:
Characterise how seaweeds perform, specifically seaweed SGR,
nutrient absorption capacity, nutritional quality and epiphytic
assemblages.
Are the cultivated seaweeds suitable as a
food source?
What was the biofilitering capacity?
Seaweed cultivation: Seaweed cultivation: Western CapeWestern Cape
Small & medium tanks using abalone or fish effluent
Large tanks used 5 x 1 m
y = -0.4557x + 3.2565p < 0.05
0
2
4
6
8
0 1 2 3 4 5 6
B-B scale of infection
SGR
(% D
ay)
BAD INFECTION
DEAD
RESULTS: RESULTS: Myrionema strangulans Myrionema strangulans (new record & range (new record & range
extension)extension)
HEALTHY
INFECTED
RESULTS: RESULTS: Tissue Nitrogen vs. Thallus Tissue Nitrogen vs. Thallus ColourColour
Seaweed tank Seaweed tank
3 KW.hr pump3 KW.hr pump
Gravity feed Gravity feed
Abalone tanksAbalone tanks
Seaweed tank Seaweed tank
25 % Recirculation 25 % Recirculation
75 % Sea water 75 % Sea water
Over flow Over flow
Pilot scale integrationPilot scale integration
5.0
7.0
9.0
11.0
13.0
incoming sea Seaw eed tanks
RESULTS: RESULTS: Dissolved oxygen (mg.LDissolved oxygen (mg.L-1-1))
15 16 20 00 04 08 12 16 20 00 04 08 12 16
5
7
9
11
13
Incoming sea 25 % Recirculation Seaw eed tanks
RESULTS: RESULTS: Dissolved oxygen (mg.L-1)Dissolved oxygen (mg.L-1)
15 16 20 00 04 08 12 16 20 00 04 08 12 16
Dissolved oxygen transfer 33 % loss from seaweeds to abalone
tanks.
RESULTS: RESULTS: Temperature (Temperature (ºC)ºC)
7
12
17
22
27
Incoming sea Seaw eed tanks 15 16 20 00 04 08 12 16 20 00 04 08 12 16
RESULTS: RESULTS: Temperature (Temperature (ºC)ºC)
7
12
17
22
27
Incoming sea 25 % Recirculation Seaw eed tanks 15 16 20 00 04 08 12 16 20 00 04 08 12 16
Temperature 4 % higher in integrated tanks over 18
month period
Results:Results: Nutrient uptakeNutrient uptakeResults:Results: Nutrient uptakeNutrient uptake
Nutrient analysis showed the system to be nitrogen limited and that the system was very efficient at removing nitrogen based wastes.
Nutrient analysis showed the system to be nitrogen limited and that the system was very efficient at removing nitrogen based wastes.
% difference in nutrient
uptake efficiency FAN TAN PO4 NO3 NO2
25 % Recirc. abalone vs. FTS abalone
54.85 38.06 0 64.8 48.8
0
2
4
6
8
10
12
FTS 25 % Recirc.
Dry
mas
s (m
g/L
)
50 < µm 40 - 50 µm 30 - 40 µm 20 - 30 µm
Other results:Other results:Other results:Other results:Seaweed SGR
Tissue nutrients
Abalone health
Bacteria
Sediments
Abalone growth rates
Mobile macro fauna
Seaweed SGR
Tissue nutrients
Abalone health
Bacteria
Sediments
Abalone growth rates
Mobile macro fauna
0
5
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Jan-
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Mar
-04
May
-04
Jul-0
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Sep
-04
Nov
-04
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-05
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-05
Jul-0
5
Sep
-05
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-05
Ulv
a b
iom
ass
(kg
/tan
k)
Recirculation Fertilized flow through
20
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80
90
Jun-03 Oct-03 Jan-04 Apr-04 Aug-04 Nov-04 Feb-05 May-05 Sep-05
Leng
th (
mm
)
25 % Recirc. FTS
No significant differencesNo significant differences
Potgieter, 2005Potgieter, 2005Lindstrom, 2006Lindstrom, 2006 Brandt, 2006Brandt, 2006Flodin, 2005Flodin, 2005Hansen, 2006Hansen, 2006Robertson-Andersson, 2003, 2007Robertson-Andersson, 2003, 2007Sankar, 2003Sankar, 2003Bredberg, 2003Bredberg, 2003
Commercial integrated seaweed abalone system:Commercial integrated seaweed abalone system: 50 % recirculation50 % recirculationCommercial integrated seaweed abalone system:Commercial integrated seaweed abalone system: 50 % recirculation50 % recirculation
Intake Intake
Seaweed paddle ponds Seaweed paddle ponds
Sump Sump
Drum filter Drum filter
Abalone
tanks
Abalone
tanks
Header tank Header tank
Pump Pump
Seaweed harvest
point
Seaweed harvest
point Outlet Outlet
FEED SAVINGS:
4 ponds produce 120 tons of feed a year at a cost of ZAR 1
100 therefore a direct rand value of ZAR 132 000.
The cost of 1 ton of kelp ranges from ZAR 950 – ZAR 1 250
per ton with a FCR of between 1: 12.5 – 17 (I & J farm data).
Cultivated Ulva has an FCR of 1: 3.6 (I & J farm data) due to its
higher protein content and this means that the
equivalent feed value is ZAR 478 500.
SEAWEED PADDLE POND SYSTEM: SEAWEED PADDLE POND SYSTEM: Costs and savingsCosts and savingsSEAWEED PADDLE POND SYSTEM: SEAWEED PADDLE POND SYSTEM: Costs and savingsCosts and savings
ZAR 360 000 to build 4 ponds ZAR 7.5 = $ 1 ZAR 7.5 = $ 1
SEAWEED PADDLE POND SYSTEM:SEAWEED PADDLE POND SYSTEM: Costs and savings Costs and savings
SEAWEED PADDLE POND SYSTEM:SEAWEED PADDLE POND SYSTEM: Costs and savings Costs and savings
ZAR 360 000 to build 4 ponds
PUMPING SAVINGS:
Due to the reduced head heights when pumping the total savings
from having this system is an average of 20 KW.h-1.
Electricity costs per KVA are around 16 c per unit (bulk usage for Gansbaai
district, ESKOM, 2006).
If we assume that the power correction factor for a pump is equal
to 1, then 1 KVA is equal to 1 KW.
A 20 KW saving over a year would equal ZAR 20 032.
ZAR 7.5 = $ 1 ZAR 7.5 = $ 1
SEAWEED PADDLE POND SYSTEM: SEAWEED PADDLE POND SYSTEM: NegativesNegativesSEAWEED PADDLE POND SYSTEM: SEAWEED PADDLE POND SYSTEM: NegativesNegatives
Two farms which feed Ulva and Gracilaria exclusively
experienced that their abalone developed an ‘off’ taste
and sulphur-like smell after the canning process.
Taste and smell due to evolution of DMS from DMSP.
Caused when abalone ingest algae high in DMSP
particularly cultivated U. lactuca.
DMS in cans up to 44 μg.ml-1.
Taste threshold of DMS in water about 1000 times lower
However, abalone with high DMSP concentrations are
preferred in the raw state.
Two farms which feed Ulva and Gracilaria exclusively
experienced that their abalone developed an ‘off’ taste
and sulphur-like smell after the canning process.
Taste and smell due to evolution of DMS from DMSP.
Caused when abalone ingest algae high in DMSP
particularly cultivated U. lactuca.
DMS in cans up to 44 μg.ml-1.
Taste threshold of DMS in water about 1000 times lower
However, abalone with high DMSP concentrations are
preferred in the raw state.
A A A
A A
B
B
B
B
B
B
B B
C
C C
C
C
C C
D
D
D
D D
D
D
E E
E E
E E
Uncooked Cooked
ABALONE
SEAWEED
CULTIVATIO
N in 2006
SEAWEED
HARVEST
CANNIN
G
ABFEE
D
Laborers 814 12 388 (600 –
1000)
67 16
Tonnage (tons) 850 1056 11019 150 360
Pay (ZAR) 1813 1813 1484 2464 2464
UnSkilled (%) 61 85 88 0 50
Male :female 1:0.23 1:0 1:2 1:0.23 1:0
Investment (ZAR) 346 500
000
3 760 000 260 000 000 2 000 000 750 000
Socio-economic effects from seaweed Socio-economic effects from seaweed cultivation in comparison to abalone cultivation in comparison to abalone
farming and related industries in SA in farming and related industries in SA in 20052005
Conclusion:Conclusion:
Integrated seaweed cultivation has developed due to economic drivers,
mainly from the abalone cultivation industry.
The fact that U. lactuca is the largest aquaculture product in temperate
Southern Africa is testament to the success of this type of aquaculture.
This development has only been possible through cooperation between
research institutions and commercial enterprises.
DOMO ARIGATO GOZAIMASSDOMO ARIGATO GOZAIMASS
THANK YOUTHANK YOU
ACKNOWLEDGEMENTS
I would like to extend special thanks to the following
organizations without whose help this project would
have
been impossible:
Swedish and South African Collaborative Program
I & J Mariculture farm
N R F
SANCOR Prestige Student travel grant