New Internationalist

The Blue Revolution

Issue 234

new internationalist
issue 234 - August 1992

[image, unknown]

The Blue Revolution
From salmon cages anchored in icy Norwegian fjords to prawn ponds carved
out of Thailand's mangrove forests, fish farming is big business. Rick Boychuk investigates the 'blue revolution' that is changing ocean shorelines around the globe.

Like the Green Revolution of the 1960s, the Blue Revolution a decade later was supposed to increase global food production miraculously and stave off widespread hunger.

By 1985, the World Bank, the Asian Development Bank and a variety of other international aid agencies were pumping $200 million a year into aquaculture projects. Mangrove forests in the Philippines, Thailand and Ecuador were chopped down to make way for shrimp ponds. Carp and tilapia farms were staked out on the flood plains of the Ganges, the Irrawaddy and the Mekong rivers.

As a result the production of pond-raised fish has boomed. Nearly 12 per cent of the annual world harvest of fish (about 100 million tons) is now generated by fish farmers. From 1975 to 1985 world aquaculture output doubled.

Commercial fish farming is now big business. The question is: has this new techno-fix to boost world food production helped to feed the hungry?

Let's look at the cultivated shrimp industry. Shrimp ponds, which now dot coastlines from Taiwan to Ecuador, are capital intensive and have led to the destruction of thousands of hectares of mangrove forests. They've also generated steady flows of polluted wastewater and contributed to the decline of wild shrimp fisheries.

In Ecuador, shrimp-pond investors include Coca-Cola and General Foods. In Thailand, the poor living in coastal communities have taken up arms to prevent corporations from seizing commonly owned mangrove forests for shrimp ponds.

Nonetheless, the industry continues to expand. In a recent issue of Aquaculture magazine, El Salvador was described as the newest ideal location for intensive coastal shrimp farming. The authors of the article say the Government is offering foreign aquaculture investors a 10-year tax holiday and unrestricted repatriation of profits. In addition, a local NGO is offering to finance up to 80 per cent of the capital costs and 60 per cent of the operating costs for aquaculture projects.

'People have been killed defending their land along the coast,' says Ian Filewod of the Canadian Council for International Co-operation. The owners of the ponds tend to be businesspeople and urban investors. And the shrimp produced don't grace the dinner dishes of the hungry poor.

The compelling attraction of intensive commercial aquaculture is that it generates export revenue that can be used to pay foreign debt. In addition, it's relatively efficient: beef cattle require seven pounds of grain to produce a pound of meat. Catfish require only 1.7 pounds of grain to produce a pound of fish.

It was the Japanese who first recognized that the era of hunting fish was ending. In response, nearly a century ago, they began to build what is today the world's largest marine aquaculture industry.

Before 1939, the Japanese were producing about 76,000 tons a year. By 1987, their production had increased to 1.1 million tons. Along their coastlines, the Japanese farm salmon, prawn, flounder, yellowtail, red sea bream and other species with high market value.

Critics believe if this kind of explosive growth occurs elsewhere the increase in the commercial fish harvest will come at the expense of both wild fish stocks and the environment. Fisheries expert Brian Davy of the International Development Research Centre says major disease and pollution problems are already emerging in Japan. Fish waste and uneaten fish food have accumulated on the sea bottom.

In some places the sludge below cage sites is more than 30 centimetres thick. The waste stifles the growth of aquatic organisms and causes water quality to deteriorate. Intensive coastal fish farming has also been linked to 'red tides' - an explosive growth of toxic algae that can kill fish and fatally poison people who eat contaminated seafood.

Brian Davy says the Japanese dealt with pollution caused by intensive farming by tossing antibiotics into the ponds. That treatment in turn led to 'increased drug resistance and concerns over excessive use of medication for a food crop.'

In the 1980s, along Canada's Pacific coast, ITT and other corporations invested heavily in salmon farming. There are now 125 salmon operations along what is known as the Sunshine Coast. Ten Dawe of the Ocean Resources Conservation Alliance says the farms have been a disaster. Dawe says the salmon pens have triggered red-tide outbreaks and polluted the foreshore with waste and the biocides, antibiotics and other medicines used to treat the fish.

'An average salmon farm produces a volume of effluent equal to a town of 40,000 people,' says Dawe. In addition, she says, the pens frequently break and the farm-bred salmon then make their way into rivers where they force out wild salmon - a kind of genetic pollution.

'Historically, unique salmon populations have evolved in each river. They are well adapted to the conditions in their own river,' says Dawe. Genetically homogenizing the salmon makes the fish much more vulnerable to environmental change.

Dawe says the farmed salmon are also responsible for infecting wild salmon with a variety of diseases - including sea lice, which deform the fish, and bacterial kidney disease. Fish farmers normally expect losses from disease of 25 to 30 per cent. Dawe says if salmon are to be farmed they should be raised in tanks on land and all the effluent should be treated.

'I still wouldn't eat farmed salmon,' he adds, 'but if others want to, that's their business.

Bruce McKay, a marine mammal researcher with Greenpeace, says a parasitic fluke from a salmon hatchery in Sweden spread to Norway several years ago and has now turned up in 27 rivers.

'The entire wild salmon population in Norway is now at risk,' he warns. 'I firmly believe the success of marine aquaculture as an industry will be at the expense of existing fisheries.'

Gary Spiller, a fisheries consultant who worked for the UN Food and Agriculture Organization in Asia, says disease is common where fish farms are not closely regulated. In 1987 Taiwan became the largest prawn producer in the world. A year later disease struck and production dropped by 70 per cent. The industry never recovered. Spiller says Taiwan was just the first to crash. The Philippine prawn industry is currently suffering from disease problems and experts predict prawn farms in Thailand will be hit next.

The Brundtland Commission, which endorsed the promise of aquaculture, noted that the major constraint to expansion of the industry is science. 'Because marine biologists have not been able to get some commercial species to reproduce in captivity, fish farmers are still largely dependent on the gathering of eggs or the capture of fingerlings.'

Fisheries scientists across the globe are now working to overcome that technical barrier to expansion of the industry. Their efforts are characterized by industry supporters as a race against hunger: if natural stocks of fish are not enough to meet demand, then fish farmers will come to the rescue. That line of reasoning troubles many. Philippine prawn farms are not producing food for the hungry, nor are they providing employment for hundreds of jobless sugar workers.

At last count there were more than 30,000 prawn farms in 40 countries. Many were carved out of mangrove swamps, which protected shorelines from erosion and were the nurseries for thousands of marine organisms.

Others were simply schemes that allowed the wealthy to privatize what had previously been a public resource used by subsistence farmers and fisherfolk. Researcher Wolfgang Harris studied two villages in Java and found that as prawn and fish farming expanded so did the landholdings of the wealthy. The losers were villagers who, for generations, had been cultivating fish in small ponds for local consumption.

The environmental problems posed by attempts to assume nature's responsibility for managing fish stocks are even more troubling. Ray Hilborn, a biologist at the University of Washington, says there is a danger that science will provide a smokescreen for environmental degradation. Hilborn says that along the west coast of North America fisheries managers have responded to salmon habitat loss and over-fishing by developing hatcheries. Salmon eggs are harvested in the wild, hatched and then reintroduced into depleted rivers.

According to Hilborn the same tactic is now being suggested for herring, tuna, abalone and giant clams. Money that should be spent on habitat protection or restoration is instead being spent on restocking. Hilborn claims this approach both encourages careless exploitation and reduces species diversity.

Canadian fisheries scientist Jack Christie, like other aquaculture critics, believes that the real contribution to world protein needs will continue to come from wild fish and from small-scale tropical pond culture.

But he worries that expansion of coastal fish farming will damage the wild fisheries: most of the world's marine fish catch reproduces in coastal areas. And that's exactly where the environmental impact of fish farming is most acute. The Blue Revolution's promise of precious protein to feed the world's hungry appears now to be hollow rhetoric. And its enduring legacy may be the gradual but calamitous decline of wild fish stocks.

Rick Boychuk is an investigative journalist based in Ottawa.

previous page choose a different magazine go to the contents page go to the NI home page next page


This first appeared in our award-winning magazine - to read more, subscribe from just £7

Comments on The Blue Revolution

Leave your comment