THE RISE AND RISE OF FISH FARMING

The leaping salmon has long been a symbol of freedom and one of nature's great wonders, but with the advent of fish farming the 'king of fish' has lost its crown. Instead of the ocean wanderer returning to its home river to spawn, it has been relegated to just one more factory-farmed commodity. Fish farming is now the world's fastest growing sector of animal production, and salmon and trout form the mainstay of Britain and Europe's 'aquaculture' industry, with further species such as cod, halibut and turbot being added to the list as wild populations crash due to overfishing.

Caged, Crowded and Cramped

Fish farms can be as intensive as anything found on terra firma. Up to 50,000 salmon are crowded in a single sea cage where they often swim in constant circles like caged zoo animals. Often suffering blinding cataracts, fin and tail injuries, body deformities, alarmingly high mortality, and infested with parasites, salmon are now raised intensively on the 'forgotten' factory farms under the sea. Off the Scottish west coast, for instance, salmon are reared at stocking densities equivalent to each three-quarter metre long (2.5 ft) salmon being allocated a bathtub of water. Crowding and confinement cause the fish to suffer stress, leading to greater susceptibility to disease. Wave after wave of serious disease outbreaks have caused the deaths of millions of farmed salmon, with official figures showing overall death rates of 10-30%. Such high mortality would sound alarm bells in other types of animal farming.

Infested with Parasites

Intensive farming of salmon has led to serious infestation with parasitic sea lice, which can cause great suffering and death in affected fish. These small crustaceans feed on the host salmon and damage can be so severe around the head that the living fish's skull is exposed - a condition known as the "death crown".

Current treatments centre on the use of strong nerve toxins: the fish are crammed together and bathed in organophosphates or synthetic pyrethroids, or receive chemical treatments in their feed. Other methods include bathing fish in the irritant hydrogen peroxide or using another fish, the wrasse, as a "cleaner" to literally eat the lice off the backs of the caged salmon.
Trout

The situation for farmed trout can be even worse. They are often packed into tanks or ponds 2-4 times more tightly than salmon and slaughtered in a way officially condemned for its cruelty. They can be stocked at 30-60 kg of fish per cubic metre of water, equivalent to 13 to 27 trout, each a foot (30 cm) long, to one bathtub of water. Such high stocking densities lead to high levels of fin and tail injuries.

Colorants in the Feed

Wild salmon and trout naturally eat crustaceans and algae, giving their flesh a healthy pink colour. To achieve this complexion in farmed fish, colorants are added as the flesh would otherwise appear an unappetising grey colour. The synthetic pigments, canthaxanthin and astaxanthin are used.

Cod, Halibut and Turbot

Sea fish - the last main target for man's residual hunter-gatherer instinct - are now being factory farmed. Cod farming is causing a wave of interest, not least because of the decline in the wild cod population. Cod are likely to be reared even more intensively than salmon. Cages or tanks will confine these ocean-going fish while artificial lighting may be used to manipulate the breeding cycle. I In the year 200, more than 15 tonnes of farmed cod were produced in Scotland.

One of the largest species of flatfish, the Atlantic halibut, is also firmly in the farmers' frame. These enormous fish can grow to weights of 250 kg or more in the wild, but farmed halibut are slaughtered after 3 years at 2-3 kg. In the year 2000, 4.5 tonnes of halibut were reared in Scotland. Turbot is another farmed flatfish species and is already turning up on the shelves of several major supermarkets. In France, 900 tons of turbot were produced in 1999, with small-scale production also taking place in Scotland and Ireland.

Dying Seals and Declining Salmon

It is often claimed that fish farming takes the pressure off wild fish by providing an alternative, but in fact the reverse is true. Farmed fish are fed on wild fish in the form of fish meal: more than 3 tonnes of wild-caught fish are needed to produce 1 tonne of farmed salmon. For the newly farmed marine species such as halibut and cod, the ratio is over 5 times the weight of wild fish to produce an equivalent amount of farmed fish. Whilst the fish farming industry continues to grow rapidly worldwide, stocks of wild-caught fish such as anchovies, sardines, sand eels and capelin remain finite, with some already classified as fully exploited, overexploited or depleted.

Salmon farming has been blamed for declines in wild salmon populations and escapes from fish farms have become a fact of life with hundreds of thousands of salmon escaping annually from Scottish farms alone. Competition from these escapees, together with the transmission of diseases and parasites to wild fish, have been linked to population crashes of wild salmon in areas with large numbers of fish farms. The situation is now so bad that escaped farmed salmon outnumber catches of wild salmon by a staggering seven to one.

Few consumers realise that the true cost of cheap salmon includes the deaths of an estimated 3,500 seals every year around Scottish fish farms alone in a bid to 'control' predators. Not surprisingly, huge numbers of fish in one place form an irresistible attraction to wildlife such as fish-eating birds, seals, mink and otters, and some farmers see the killing of wild animals as a legitimate part of predator control: animals are chased by boats in an attempt to drive them away and those that fail to get the message may be shot.

Environmental Impact

Keeping large numbers of fish concentrated in a small area has led to the pollution of the surrounding environment. Fish wastes, excess feed and farm chemicals all contribute. Solid wastes settle to form sediment beneath the salmon cage and in the surrounding area, killing underlying marine life. Decaying sediment also causes deoxygenation of the water column and the release of damaging compounds such as phosphates, hydrogen sulphide and methane into the water. The area may become more susceptible to deadly toxic algal blooms.

For every tonne of salmon produced, an estimated 100 kg of nitrogenous compounds such as ammonia are released. Scotland's fish farm industry is estimated to have produced 7,500 tonnes of nitrogen in the year 2000, comparable with the annual sewage output of 3.2 million people.

Starvation and Slaughter

About 35 million salmon and as many trout are slaughtered annually in the UK - more than all the pigs, sheep, cattle and turkeys put together - and they are often killed in ways which cause such intolerable suffering that the perpetrators would be prosecuted for slaughtering other farm animals in a similar way.

Farmed fish are normally starved for about 7-10 days before slaughter. Killing methods for trout include suffocation in air or on ice. The cooling effect of the ice prolongs the time it takes for the suffocating fish to become unconscious and they may still be conscious up to 15 minutes after being taken from the water.

Salmon farmers are increasingly using percussive stunning techniques, whereby a single blow to the head kills the fish. However, a particularly cruel slaughter method still used for some salmon and trout is the use of carbon dioxide stunning. The fish are placed in a bath of carbon dioxide saturated water, which causes them to thrash around. They stop moving after 30 seconds, but do not lose consciousness for 4-9 minutes, so when their gills are cut with a knife as part of the slaughter process they may be immobile but still conscious as they bleed to death.

Troubled Waters

Intensive fish farming has resulted in cheap salmon and trout being readily available at the supermarket checkout. However, the true cost includes the suffering of the fish themselves, declines in wild fish populations, dead seals, and the damage inflicted on the environment. As these issues rise to the surface, the battle for common sense and compassion beneath the water has begun.

PHILIP LYMBERY

The Vegan, Autumn 2002

Philip Lymbery is an international animal welfare consultant based in the UK. Before going freelance, Philip was campaigns director for leading European farm animal welfare organisation Compassion In World Farming (CIWF), where he worked for a decade (1990-2000). He is author of the CIWF Trust report, "In Too Deep - The Welfare of Intensively Farmed Fish" (2002).