INTEGRATED SEAWEED/ABALONE MULTITROPHIC RECIRCULATING AQUACULTURE (IMTA) IN SOUTH AFRICA: BALANCING THE BALANCE SHEETS, ENVIROMENT AND COMMERCE Deborah V. Robertson-Andersson 1 , Ana M. Nobre 2 , Amir Neori 3 , Kishan Sanker 6 , Gavin Maneveldt 1 , Max Troell 4,5 , Christina Halling 5 and John J. Bolton 6 1 The Department of Biodiversity and Conservation Biology Department, University of the Western Cape, Bellville, South Africa. 2 IMAR, Faculty of Sciences and Technology/UNL. Caparica, Portugal. 3 Israel Oceanographic and Limnological Research, National Centre for Mariculture, Israel. 4 Beijer Institute, Stockholm, Sweden. 5 Department of Systems Ecology, Stockholm University, Stockholm, Sweden. 6 Botany Department, University of Cape Town, South Africa.

How to convince an abalone farmer to also farm seaweeds Deborah V. Robertson-Andersson 1 , Ana M. Nobre 2 , Amir Neori 3 , Kishan Sanker 6 , Gavin Maneveldt 1 , Max Troell 4,5 , Christina Halling 5 and John J. Bolton 6 1 The Department of Biodiversity and Conservation Biology Department, University of the Western Cape, Bellville, South Africa. 2 IMAR, Faculty of Sciences and Technology/UNL. Caparica, Portugal. 3 Israel Oceanographic and Limnological Research, National Centre for Mariculture, Israel. 4 Beijer Institute, Stockholm, Sweden. 5 Department of Systems Ecology, Stockholm University, Stockholm, Sweden. 6 Botany Department, University of Cape Town, South Africa.

How do you tell an economist the value of science?

How do you tell an economist the value of science?

How do you tell an economist the value of science? most scientists - seem to take it for granted that scientific knowledge is valuable for its own sake value of science must depend exclusively upon the value of its effects or consequences which somehow affect the welfare or happiness of sentient beings draw up a debit and credit account" for science Lars Bergström Notes on the Value of Science

How do you tell an economist the value of science?

most scientists - seem to take it for granted that scientific knowledge is valuable for its own sake

value of science must depend exclusively upon the value of its effects or consequences which somehow affect the welfare or happiness of sentient beings

draw up a debit and credit account" for science

Lars Bergström Notes on the Value of Science

Overview How does a phycologist draw up a credit and debit account?

How does a phycologist draw up a credit and debit account?

Overview How does a phycologist draw up a credit and debit account? Ecological-economic assessment by Differential Drivers-Pressure-State-Impact-Response (DPSIR) approach Places an economic value on IMTA by looking at the costs/benefits of implementation of the system compared to a system without IMTA The current drivers for integrated seaweed aquaculture in South Africa. Socio-economic, environmental and multiplier effects.

How does a phycologist draw up a credit and debit account?

Ecological-economic assessment by Differential Drivers-Pressure-State-Impact-Response (DPSIR) approach

Places an economic value on IMTA by looking at the costs/benefits of implementation of the system compared to a system without IMTA

The current drivers for integrated seaweed aquaculture in South Africa.

Socio-economic, environmental and multiplier effects.

Differential DPSIR (i) Drivers - the anthropogenic activities at a given moment in time that may have an environmental effect and is a socio-economic component of the DPSIR. (ii) Pressure - positive or negative direct effects of the Drivers (iii) State - the condition of the ecosystem at a given moment in time resulting from both anthropogenic Pressures and natural factors. (iv) Impact - the environmental effect of the Pressures , i.e. the changes on the State of the ecosystem during a given time period or between two scenarios. An environmental Impact can be either positive or negative. (v) Response - management actions and policies that change the Drivers .

Drivers Lack of and decrease in kelp resource to feed increasing industry. High seawater temperatures cause artificial feed to ferment and bloat abalone. 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. Rational for IMTA Effect of diets on abalone growth rates Naidoo et al. 2006

Drivers

Lack of and decrease in kelp resource to feed increasing industry.

High seawater temperatures cause artificial feed to ferment and bloat abalone.

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.

Effect of harvesting on regrowth of obligate epiphytes on kelp Anderson et al. 2006 Drivers Lack of and decrease in kelp resource to feed increasing industry. High seawater temperatures cause artificial feed to ferment and bloat abalone. 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. Rational for IMTA

Drivers

Lack of and decrease in kelp resource to feed increasing industry.

High seawater temperatures cause artificial feed to ferment and bloat abalone.

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.

Red tide moving towards abalone intake Drivers Lack of and decrease in kelp resource to feed increasing industry. High seawater temperatures cause artificial feed to ferment and bloat abalone. 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. Rational for IMTA

Drivers

Lack of and decrease in kelp resource to feed increasing industry.

High seawater temperatures cause artificial feed to ferment and bloat abalone.

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.

Commercial integrated seaweed abalone system: 50 % recirculation Intake Seaweed paddle ponds Sump Drum filter Abalone tanks Header tank Pump Seaweed harvest point Outlet

Feed savings – 120 tons of seaweed produced Faster abalone growth rates – 6 months less spent on farm Energy reduction – 350 MWh yr -1 Reduction in concentration and total mass of discharged nutrients R104 per kg N removed R48 per kg P removed Kelp beds not being harvested R146 per m 3 Change in GHG emission R 200 per ton CO 2 Benefits of an IMTA SYSTEM:

Feed savings – 120 tons of seaweed produced

Faster abalone growth rates – 6 months less spent on farm

Energy reduction – 350 MWh yr -1

Reduction in concentration and total mass of discharged nutrients

R104 per kg N removed

R48 per kg P removed

Kelp beds not being harvested

R146 per m 3

Change in GHG emission

R 200 per ton CO 2

Cost to build to 1 pond in IMTA system R 51 000 Total cost for 4 ponds R 0.3 million (once off cost) Labor for seaweed ponds R140 000.yr -1 Costs of an IMTA SYSTEM:

Cost to build to 1 pond in IMTA system

R 51 000

Total cost for 4 ponds

R 0.3 million (once off cost)

Labor for seaweed ponds

R140 000.yr -1

Feed savings – R 235 000 yr -1 Faster abalone growth rates – R 720 000 yr -1 Energy reduction - R 56 000 yr -1 Discharged nutrients 44 % decrease in N production 23 % decrease P production Kelp beds 2.2 ha.yr -1 not being harvested Change in GHG emission 345 tons.yr -1 ton CO 2 Impacts of an IMTA SYSTEM:

Feed savings – R 235 000 yr -1

Faster abalone growth rates – R 720 000 yr -1

Energy reduction - R 56 000 yr -1

Discharged nutrients

44 % decrease in N production

23 % decrease P production

Kelp beds

2.2 ha.yr -1 not being harvested

Change in GHG emission

345 tons.yr -1 ton CO 2

Impacts ENVIRONMENTAL SAVINGS (82 % of the net profit) The seaweeds take up 12 tons of CO 2 y -1 An additional 333 tons of CO 2 y -1 are saved by reducing the electricity usage 92.6 % of N is removed A 3 % reduction in the harvesting of natural kelp beds 6 % decrease in green house gas emissions by the farm 17.8 % increase in P emissions NET PROFIT = R 62. 791 million.yr -1

ENVIRONMENTAL SAVINGS (82 % of the net profit)

The seaweeds take up 12 tons of CO 2 y -1

An additional 333 tons of CO 2 y -1 are saved by reducing the electricity usage

92.6 % of N is removed

A 3 % reduction in the harvesting of natural kelp beds

6 % decrease in green house gas emissions by the farm

17.8 % increase in P emissions

SEAWEED PADDLE POND SYSTEM: Costs and savings ENVIRONMENTAL SAVINGS: 49 800 Euro yr -1 of avoided costs for N removal; 1 400 Euro yr -1 estimated as the environmental costs for the increase in the P loads; 300 Euro yr -1 of avoided costs concerning kelp bed restoration; 4 500 Euro yr -1 of avoided costs of GHG emission offset. The economic value = 494 200 Euro yr -1 direct benefits to the aquaculture business (estimated as the change in the aquaculture net profit, 53 200 Euro yr -1 (ZAR 871 000 )) and indirect environmental benefits (estimated as the value of the externalities, 541 000 Euro yr -1 (ZAR 3839 000)) ZAR 9.495 = € 1 * * FMI 2007 and includes purchasing power parity

ENVIRONMENTAL SAVINGS:

49 800 Euro yr -1 of avoided costs for N removal;

1 400 Euro yr -1 estimated as the environmental costs for the increase in the P loads;

300 Euro yr -1 of avoided costs concerning kelp bed restoration;

4 500 Euro yr -1 of avoided costs of GHG emission offset.

The economic value = 494 200 Euro yr -1

direct benefits to the aquaculture business (estimated as the change in the aquaculture net profit, 53 200 Euro yr -1 (ZAR 871 000 )) and

indirect environmental benefits (estimated as the value of the externalities, 541 000 Euro yr -1 (ZAR 3839 000))

Conclusion: Nick Loubser I & J General manager “ The actual financial benefits are difficult to determine but in ball park terms we calculate that the seaweed contributes at least R500 000 a year to the farm in feed cost savings alone.” Our calculations show a savings of R871 000 per year. McVeigh, S. J.. 2007. First Green Filters for aqauculture. Fishing industry news. June 2007. pg 16 - 17.

Nick Loubser I & J General manager

“ The actual financial benefits are difficult to determine but in ball park terms we calculate that the seaweed contributes at least R500 000 a year to the farm in feed cost savings alone.”

Our calculations show a savings of R871 000 per year.

McVeigh, S. J.. 2007. First Green Filters for aqauculture. Fishing industry news. June 2007. pg 16 - 17.

THANK 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