COPPER ALLOY MESH IN MARINE FINFISH CAGE CULTURE A scoping study in southern Africa

Tom HechtADVANCE AFRICA Management Services

cc

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

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.

AVAILABLE COPPER ALLOYS FOR MARINE CAGES

UR30TM COPPER 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

Most commonly used alloy

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.

Scoping study objectives

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)

Farm locations: South Africa

Country overviews : South Africa Abalone 980 t

pa12 farms

Land based pump ashore

Seaweed for abalone feed

Artificial feeds

Mussels, 600-800 t pa, Spanish raft, Saldanha Bay, 2 farms Oysters: 450 t pa,

mainly PE, Saldanha, Knysna. Consumed locally and some exported EU. Kob

broodtsock

Pemba (Mozambique) Richards Bay

Yellowtail cages, Algoa Bay 2009 - 2011

Planned farms:

Mosselbay - YellowtailSaldanha, - 2 x SalmonExperimental - Algoa Bay (Yellowtail) Richards Bay (Kob)

Country overview: MozambiqueCurrent 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 KobInvestor: HIK Abalone, Hermanus.Pre-commercial phase 2009-2011 @ US$3 millionCommercial phase 2012> to 2000 t pa @US$ 7 million

Rating Sitelocation

Country Cage type Additionalinformation needed

A++ Pemba Mozambique Surface None A++ Nacala Mozambique Surface Depth profiles,

Bottom type, Current speedsWater quality

A+ Saldanha Bay South Africa Surface NoneA+ Mosselbay South Africa Surface Water quality

dataA Algoa Bay South Africa Surface/

SubmergedSignificant wave height andwater quality data

B- Gansbaai South Africa Surface/Submerged

Depth profiles,Bottom type, Current speedsSignificant wave height

Plus Seychelles, Madagascar, Reunion, Mayotte, Mauritius

Southern area

Northern area (probably too exposed)

Central area

Possible cage culture areas in outer bay of Nacala

The problemsNet fouling, Algoa Bay

Predators (Barracuda) inside net pen

The potential for cage culture

Farm Location Tonnes pa Number of Cage ø Net depth Area/cage Netting requiredcages (m) (m) (m^2) (m^2)

1 Mosselbay 2000 40 35 8 880 35 2002 Saldanha 1000 18 40 15 1 886 33 9433 Saldanha 1500 26 35 15 1 650 42 9004 Pemba 2000 20 25 10 786 15 714

Total 127 75710 year horizon 50 000 500 35 12 1 320 660 00020 year horizon 90 000 900 35 12 1 320 1 188 000

TOTAL 1 975 757

Term Years RSA MozambiqueShort 5 5 000 2 000Medium 10 15 000 12 000Long 20 45 000 35 000

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 countriesRegulatory authorities -- were enthusiastic as they recognised the application to realize development goals.

Farmer response -- cautious optimism to quiet enthusiasm. Not surprising. (Who jumps in first?)

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 frequent questions = product lifespan, cost, env. impact, additional floatation.

Primary motivators: Intense biofouling and predators

REGULATORY APPROVALDear 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.

Regards

Michelle Pretorius (Cand. Sci. Nat.)Department of Agriculture, Forestry & FisheriesPrincipal Enviornmental Officer: Marine Aquaculture EnvironmentalAssessment

Tel: +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

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).

Conclusions and recommendations

A. Selection of partners for commercial trials1. The AquaPemba Cobia project in Pemba, Mozambique (HIK Abalone)2. The University of Stellenbosch / Dept. Of Science & Technology Dusky Kob project in Richards Bay OR Yellowtail project in Algoa Bay

B. Experimental systems and design 1. Comparative growth and production trials2. Anti-fouling demonstration project

C. Implementation and project management

D. Pro forma Budgets

THE REST

Comparison of Commercial partnersAquaPemba 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.

IDEA FOR CDA (Africa)