seaweed paddle pond systems

SEAWEED PADDLE POND SYSTEMSSEAWEED PADDLE POND SYSTEMS

• Mixed diet gives better growth rates Mixed diet gives better growth rates • MSY of kelp bed reached in 2002 MSY of kelp bed reached in 2002

– Potential Potential over-harvesting over-harvesting – Decrease in epiphyte densitiesDecrease in epiphyte densities

• Limited suitable coastal areasLimited suitable coastal areas• ‘‘HAB’s’HAB’s’ • RecirculationRecirculation• IIntegration will improve water qualityntegration will improve water quality

Why cultivate seaweeds on your farm?Why cultivate seaweeds on your farm?

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEMEFFLUENT CHANNEL INLETEFFLUENT CHANNEL INLET

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

INLETINLET

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEMSLUICE GATESLUICE GATE

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEMINLETINLET

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

PADDLE AND DRIVEPADDLE AND DRIVE

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

POND PROFILE VIEWPOND PROFILE VIEW

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

PADDLE WHEELPADDLE WHEEL

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEMMIDDLE DIVIDER WALLMIDDLE DIVIDER WALL

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

OUTLET BARRIEROUTLET BARRIER

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

OUTLETOUTLET

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

EFFLUENT AND HARVESTING CHANNELEFFLUENT AND HARVESTING CHANNEL

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

HARVESTING AREAHARVESTING AREA

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

PARENT STOCKPARENT STOCK

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

PADDLE POND DESIGNPADDLE POND DESIGN

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

COST OF A SINGLE PONDCOST OF A SINGLE POND Concrete casted 40000

Sand floor (compacted) 1400

HDPE white liner 750 micron 2 X 6 X 38 m 8800

Coverstrips 8 mm X 40 mm X 120 m HDPE 1500

S/S screws 40 mm X 4.2 mm X 500/pond 225

Elec motor and gearbox 3 KW & chain & sprockets 10400

Paddle and bearings 9000

Cover for elec motor (fibreglass) 450

Channel @ R650/m X 18 11700

Sluice gate for incoming water 350

Civils to level out & compact platform @ R25/m2 6840

Elec cable for supply and D. B. 3500

TOTAL 94165

Why is a controlled feed source important?

• Abalone are herbivores

• They obtain all of their protein requirement from their diet

• Their FCR is affected by phenols (an anti-grazer deterrent produced by most seaweeds)

• Kelps can contain very high proportions of phenols

• Abalone obtain all their calcium requirement through their gills, but no phosphate

• The phosphate requirement has to be met by the diet

• Abalone are sold by weight and there can be up to a 30% water loss during transport

RESULTS

Important because:

• Increases protein from wild harvest (3.7- 24 % wild to 49.8 % cultured)

• Abalone receive more protein

• Faster growth rates

How do you increase tissue nutrients?

• Faster flow rates (12 – 20 volume exchanges)

• Grown in turbot/fish or abalone effluent

• Add Fertilizer and Kelpak®

Tissue Nitrogen

RESULTSTissue Nitrogen vs. Thallus Colour

Tissue nitrogen vs. thallus colour

RESULTSTissue Nitrogen vs. Tissue Phosphorus

Tissue N vs. Tissue P

0

10

20

30

40

50

Time

Rat

io o

f N:P

w ild stock turbot abalone

Small sea Medium sea

A S O N D J F M A M J J A

West Coast

Benefits of a closed system

• Increase in temperature above ambient seawater equates to an increase in growth rates

• Decrease in pumping costs

• Additional safety in times of red tide and oil spills

RESULTS

Ulva can take up 90 % of ammonium in abalone effluent at 12 volume exchanges per day

• DO values don’t go below 9 mg.l-1 at night

• Using stocking density of 3 kg.wwt.m-2 gives best uptake rates but is system specific

• Toxic ammonia never reaches levels harmful to abalone at above stocking density

RECIRCULATION

RESULTS

Temperature in a recirculation system

Temperature

7.0

12.0

17.0

22.0

27.0

incoming sea seaw eed3

15 16 20 00 04 08 12 16 20 00 04 08 12 16

RESULTS

Temperature in a recirculation system

Temperature

7.0

12.0

17.0

22.0

27.0

incoming sea Recirc seaw eed3

15 16 20 00 04 08 12 16 20 00 04 08 12 16

RESULTS

ammonium levels in recirculated tanks range between

0.003 - 0.005 ug N.L-1

ammonium levels in abalone flow through tanks

= 0.01 ug N.L-1

Ammonium levels

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEMSEAWEED MANEGMENTSEAWEED MANEGMENT

PARENT STOCKPARENT STOCK

• Separate management strategy to pondsSeparate management strategy to ponds

• Hand removal of epiphytesHand removal of epiphytes

• Shading with 20 % shade clothShading with 20 % shade cloth

• Fertilize once weeklyFertilize once weekly

• KELPAKKELPAK®® and fresh water treatment prior to and fresh water treatment prior to out stockingout stocking

• Initial stocking density 1 kg.mInitial stocking density 1 kg.m22 = 400 kg per = 400 kg per pondpond

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEMPADDLE POND PRODUCTIONPADDLE POND PRODUCTION

FEED STOCKFEED STOCK

• Each pond initially stocked with epiphyte free Each pond initially stocked with epiphyte free materialmaterial

• Initial stocking density 1 kg.mInitial stocking density 1 kg.m22

• Harvest stocking density 5 – 7 kg.mHarvest stocking density 5 – 7 kg.m22

• Fertilize once weekly: pulse fertilization Fertilize once weekly: pulse fertilization

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

BENEFITSBENEFITS

• 1.3 tons of nutrient rich seaweed every second 1.3 tons of nutrient rich seaweed every second working dayworking day

• Easy to harvestEasy to harvest

• Potential for recirculationPotential for recirculation

• Production of controlled food sourceProduction of controlled food source

• Better quality diet for abalone Better quality diet for abalone

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

PRODUCTION FIGURESPRODUCTION FIGURES

PRODUCTION PRODUCTION = = 1.3 tons1.3 tons of nutrient rich seaweed every second of nutrient rich seaweed every second working day from paddle pondsworking day from paddle ponds

AT PRESENTAT PRESENT = = 12 platforms12 platforms

Each requiring an average of Each requiring an average of 1.8 tons1.8 tons of kelp per week of kelp per week

A four week 50 % rotation diet would require 900 kg cultivated seaweed A four week 50 % rotation diet would require 900 kg cultivated seaweed in a month per platform.in a month per platform.

Therefore total platform cultivated seaweed demand = Therefore total platform cultivated seaweed demand = 10.8 Tons10.8 Tons

16 ponds16 ponds are capable of producing are capable of producing 13.2 tons13.2 tons of seaweed in a month of seaweed in a month

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

PRODUCTION FIGURESPRODUCTION FIGURES This means that we have an excess of 2.4 tons which could feed This means that we have an excess of 2.4 tons which could feed another 2 platforms.another 2 platforms.

10.8 tons of kelp costs R115 000 now10.8 tons of kelp costs R115 000 now

Thus the ponds have a direct saving of R115 000.Thus the ponds have a direct saving of R115 000.

There is also the benefit of faster growth rates and increased There is also the benefit of faster growth rates and increased production with the same running costs due to the abalone being fed a production with the same running costs due to the abalone being fed a protein rich dietprotein rich diet

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEMECONOMICSECONOMICS

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM ECONOMICSECONOMICS

Abalone growth curvesAbalone growth curves

0

50

100

150

200

250

300

0 1 2 3 4 5 6Years

We

igh

t (g

)

von-B linear wild exponential @49 exponential@68

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

31.2 % increase in weight using rotation diet vs. kelp only diet over 9 months

Cost: $30 per kg X R 8 = R 240

10 (100g) abalone in 1 kg

cost per abalone = R 24

less profit and freight

= R 15 per abalone

ECONOMICSECONOMICS

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

Increase in SGR: Normal Growth to 100g = 5 years

accelerated growth = 3.3 – 3.6 years

@ R 15 per abalone

New cost : R 12.40 – R 13.50 per abalone

Savings: 17 – 28 %

R 1.50 - R 2.60 per abalone

ECONOMICS

SEAWEED PADDLE POND SYSTEMSEAWEED PADDLE POND SYSTEM

I & J farm (120 tons @ 100 g per abalone)

= 1 2000 000 100g abalone

X R 1.50 or R 2.60

EQUALS

Savings:

R 1.8 – R 3.12 million

ECONOMICS

Thank you for listening

SEAWEED PADDLE POND SEAWEED PADDLE POND SYSTEMSYSTEM