Aquaculture Advances: In the Past Decade, Aquaculture Has Become a $100 Billion Global Industry-The Fastest Growing Food-Production Sector since the Advent of Intensive Agriculture in the 1950s. Australia's Industry, While Still Relatively Small, Is Setting High Standards for Quality, Environmental Rigour and Innovative Research

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Ten years ago, farmed species provided only 35 per cent of the world's fish consumption. Recently the Food and Agriculture Organization of the United Nations (FAO) estimated that aquaculture now produces almost 50 per cent of the world's food fish. (1)

This success is no surprise given that, with the world's population peaking towards 9 billion by 2050, and fisheries already under severe pressure, there is a protein supply shortage that is growing particularly acute in poorer tropical regions.

Seafood--fish, crustaceans and molluscs--is an excellent source of dietary protein and healthful omega-3 fatty acids, and a primary protein source in many countries. While agriculture has only a limited ability to increase production (especially of protein crops) because of the scarcity of new arable land and water shortages, aquaculture--particularly mariculture (aquaculture in the ocean)--has significant potential to maintain its growth, and to produce the extra protein needed by the swelling population.

Standard setting

Australia has the world's third largest Exclusive Economic Zone--15.8 million square km--but its aquaculture industry accounts for only 0.8 per cent of global production.

Output has grown by only 4 per cent annually over the past decade to around $800 million a year. Tuna accounts for 34 per cent of production, Atlantic salmon 16 per cent, prawns 8 per cent and abalone 4 per cent.

Slow production growth is partly a consequence of Australia's international reputation as a leader in 'clean, green' production, according to Dr Nigel Preston, Theme Leader for Breed Engineering with CSIRO's Food Futures Flagship.

'Arguably, we have the world's most stringent controls on both sea-cage aquaculture and pond culture,' Dr Preston says. 'And every prawn producer requires a licence that sets strict limits on nutrient discharges.'

He says the Australian aquaculture industry, research agencies and funding and regulatory agencies are cooperating well to balance economic benefits with conserving coastal environments.

Australia's focus on sustainable systems that minimise pollution and disease has been a good thing, argues Dr Preston, but it has impeded the prawn industry's expansion.

Options for mass-producing fish cheaply for the Australian market are limited, but Dr Preston believes Australia can still expand its aquaculture industries within its strict nutrient-discharge requirements.

Carp (Cyprinus spp.) actually accounts for 35 per cent of the world's aquaculture harvest. But the European carp (Cyprinus carpio) is a major pest in the Murray-Darling River system and Australia is making intensive efforts to eliminate it.

Dr Preston says aquaculture producers recognise the importance of integrating production systems with good environment-protection practices.

Australia has learned rapidly from nations like India and China, where aquaculture is an ancient industry, and has developed efficient systems for dealing with its wastes.

But Dr Preston says the industry feels unfairly singled out, because upstream emitters of nutrients and sediments, including agriculture and urban areas, are not subject to the same strict controls and monitoring of nutrient discharges.

Australia's most lucrative aquaculture industry is sea-cage farming of the critically endangered southern bluefin tuna, Thunnus maccoyii, which began in 1991, after wild stocks crashed from overfishing.

The industry, now worth $300 million a year, is predicted to reach $600 million by 2010.

Between December and March, trawlers net around 5000 tonnes of juvenile tuna averaging around 20 kg each in the Great Australian Bight. They are fattened to around 30 kg in sea cages off Port Lincoln, on a diet of fresh local sardines or frozen imported baitfish. But it typically takes between 12 to 15 kg of baitfish to produce 1 kg of tuna meat. …