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A scoping study in southern Africa Tom Hecht ADVANCE AFRICA Management Services cc. Copper Alloy mesh in marine finfish cage culture . Advantages of copper alloys . High resistance to macro-fouling in sea water resulting in Improved water flow through cages,
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A scoping study in southern Africa Tom Hecht ADVANCE AFRICA Management Services cc Copper Alloy mesh in marine finfish cage culture
Advantages of copper alloys • High resistance to macro-fouling in sea water resulting in • Improved water flow through cages, • Improved DO levels, reduced parasite load, reduced infections, lower FCR, • Higher production as a consequence of faster growth and lower mortality (no net changes; no stress from predators) • The material is strong and predators cannot cause damage thereby reducing fish losses due to predation and rate of escape of fish from cages. • Lower maintenance: no net changes; no net cleaning • Lower costs: avoid need for predator net; avoid antibiotics • Reduced environmental impact: can be made from recycled materials; can be recycled after use; no nets to dispose of. • Potential for consumer market positioning as more environmentally appropriate fish production
AVAILABLE COPPER ALLOYS FOR MARINE CAGES Flattened expanded copper nickel: 90%Cu/10%Ni. Used for square rigid cages >30 yrs. Wide range of mesh size and gauges. Chain link woven UR30TM brass: 64% Cu, 35% zinc, 0.6% Sn, 0.3 %Ni plus micro-alloying elements. Appropriate for many types of flexible enclosures including circular and square cages. This material has been in use for >10 yrs. Welded silicon bronze (SeawireTM): Comprising 97% Cu, 3% Si plus manganese and micro-alloying elements. Suitable for attachment to rigid structures and for square cages.
Most commonly used alloy UR30TMCOPPER ALLOY (64%Cu, 35%Zn,0.6%Sn, 0.3%Ni and other micro-alloying elements Yellowtail in UR30 cage. Note limited bio-fouling. UR30 net being prepared for square salmon cage at Van Diemen Salmon farm, Tasmanaia
Scoping study objectives • Provide brief overviews of the current state of marine aquaculture in RSA, Namibia and Mozambique. • Outline current government policies and recent actions with respect to marine aquaculture developments. • Assess the potential size of the cage culture industry in the region. • Inform / sensitize commercial operators and fisheries / aquaculture authorities about the merits of alloy cages and assess the potential interest in alloy cages. • Identify possible local barriers to alloy cage deployment through interviews with local “environmental” NGOs • Identify any possible institutional barriers and or regulatory barriers to deployment of alloy cages. • Identify possible partners and location/s for pilot commercial trials • Assess acceptability of investment costs and or lease costs • Develop an experimental design in collaboration with farmer/s to test the efficacy of alloy cages cf. to nylon net pens. • Develop a basic costing for a commercial pilot project if desirable. • Develop the logistics for the implementation of a commercial pilot project if desirable.
Country overviews: Namibia Mariculture sites: Walvis Bay, Luderitz and Swakopmund 14 producers, mainly oysters, 2 mussel farms an d 1 shore based abalone farm. Oyster production 560 – 900 tonnes pa. Exported to SE Asia, Europe and RSA. Excellent regulatory framework (Aquaculture Act) and streamlined permitting procedures and strongly supported by Government. • Luderitz at core of central Benguela upwelling cell. • Sulphur eruptions prevalent from 50km N of Luderitz – toxic to marine organisms. • Luderitz prone to low dissolved oxygen levels . • Cage culture opportunity – Low to nil (too risky)
Country overviews : South Africa Abalone 980 t pa 12 farms Seaweed for abalone feed Land based pump ashore Mussels, 600-800 t pa, Spanish raft, Saldanha Bay, 2 farms Artificial feeds Oysters: 450 t pa, mainly PE, Saldanha, Knysna. Consumed locally and some exported EU. Kobbroodtsock Pemba (Mozambique) Richards Bay Planned farms: Mosselbay - Yellowtail Saldanha, - 2 x Salmon Experimental - Algoa Bay (Yellowtail) Richards Bay (Kob) Yellowtail cages, Algoa Bay 2009 - 2011
Country overview: Mozambique Current activities: Prawns (600 t) and seaweed (1200 t dry) Excellent regulatory framework, excellent incentives for FDI Cage culture started at Pemba, Cabo Delgado (AquaPemba) Species: Cobia and Dusky Kob Investor: HIK Abalone, Hermanus. Pre-commercial phase 2009-2011 @ US$3 million Commercial phase 2012> to 2000 t pa @US$ 7 million
Plus Seychelles, Madagascar, Reunion, Mayotte, Mauritius
The problems Net fouling, Algoa Bay Predators (Barracuda) inside net pen
The potential for cage culture Note: This excludes the potential of the entire WIO region
Dissemination of information and farmer response Information pack compiled and sent to all public and private sector stakeholders in three countries Farmer response -- cautious optimism to quiet enthusiasm. Not surprising. (Who jumps in first?) Regulatory authorities -- were enthusiastic as they recognised the application to realize development goals. Farmer opinions and questions • Except for Irvin and Johnson, farmers unaware of copper alloy mesh and cages. • University of Stellenbosch aware of copper alloy cages, previous contact with CDA (Africa). • Once aware of benefits = high degree of interest by farmers with finfish farming interests. • Oyster farmers (as expected) expressed a more cautious approach. • Most frequentquestions = product lifespan, cost, env. impact, additional floatation. Primary motivators: Intense biofouling and predators
Regulatory approval Dear Prof. Hecht,This e-mail serves to inform you that the Marine Aquaculture Directorate(DAFF) has reviewed the information supplied by you to Mr Semoli, on theuse of Copper Alloy mesh technology in marine aquaculture.The Directorate has no objections to the use of copper alloy meshtechnology for use in marine aquaculture systems.RegardsMichelle Pretorius (Cand. Sci. Nat.)Department of Agriculture, Forestry & FisheriesPrincipal Enviornmental Officer: Marine Aquaculture EnvironmentalAssessmentTel: +27 (21) 402 7034Fax: +27 (21) 434 2144Cell: 082 647 2263E-Mail: MichellePR@nda.agric.za <mailto:Phumelele.mhlongo@gpw.gov.za>Private Bag X2 Roggebaai, 8012, Cape Town
Conclusions and recommendations • Cage culture in RSA and Mozambique is nascent but interest is growing. • Emerging nature provides opportunity to expose farmers to benefits of copper alloy cages from the start. • It makes logical sense for the CDA (Africa) to undertake joint commercial trials with industry to prove the local business case. • Deployment of copper alloy panels and monitoring at selected sites would be valuable marketing tool. • Given feedback, pivotal for CDA (Africa) to develop a marketing brochure that provides indicative costs, a cost / benefit analysis, information on buyback for recycling inclusive of prices relative to new costs, possibility of leasing and costs involved, available mesh size, weight, additional floatation required, assembly modes, etc. FishAfrica - Tradeshow CT, • CDA (Africa) should further explore opportunities in the Western Indian Ocean region and in particular by Reunion (which is the most advanced country with respect to marine fish farming in the region), Seychelles, Madagascar and Mauritius. • There may be an opportunity for the CDA (Africa) to develop a new product for the oyster farming industries in Namibia and South Africa (but see below).
THE REST A. Selection of partners for commercial trials 1. The AquaPemba Cobia project in Pemba, Mozambique (HIK Abalone) 2. The University of Stellenbosch / Dept. Of Science & Technology Dusky Kob project in Richards BayOR Yellowtail project in Algoa Bay B. Experimental systems and design 1. Comparative growth and production trials 2. Anti-fouling demonstration project C. Implementation and project management D. Pro forma Budgets
Comparison of Commercial partners AquaPemba • Commercial project • Bioregion = Tropical • Cobia and kob • Commercial phase = 2000 tonnes pa • Findings not widely disseminated but success will result in further investment in WIO. • Total budget to commercial = US$1o M Stellenbosch /DST • Development project • Bioregion = Temp/Trop • Kob or Yellowtail • No direct commercial phase • Findings widely disseminated but does not necessarily lead to investment in RSA and or WIO • Total budget to completion = R6 M
Commercial trials Comparative growth and production trial. • Basic hypothesis: Because there is no biofouling the environmental conditions (through flow rate, O2) within the alloy cages should be better than in nylon cages, which will manifest in higher growth rates, lower FCR, lower stress level and “healthier” fish with lower mortality levels. Anti fouling demonstration trial • Demonstrate economic benefits of copper alloy meshes in four bioregions (Cold west coast to Tropical)
Implementation and project management – project management company to implement and project manage Pro Forma Budgets – Being drawn up at present.