Factory Fish Farms

Atlantic Salmon Pens, Huon River, Tasmania

Fish are condemmed to the appalling conditions of factory farming just as are land animals. Farming of Atlantic Salmon and Ocean Trout (Rainbow Trout grown in saline waters) is common in the estuaries of Tasmania. These fish are ‘grown’ in round netted sea cages with about 40,000 salmon crammed into each. Salmonids (this includes Atlantic Salmon and Ocean Trout) account for 90% of the fish farmed in Tasmania.

Aquaculture is the fastest growing food producing sector in the world with some experts at the 2006 World Aquaculture conference predicting that within 25 years half of all fish eaten will be farmed (read factory farmed). It is regarded by the UN Food and Agriculture Organisation to be growing at three times the rate of land-based agriculture. At present around 27% of the world seafood supply is from aquaculture.

Atlantic Salmon in the wild

Wild Atlantic Salmon are normally found in the rivers that flow into the North Atlantic Ocean, in both Europe and on the east coasts of America and Canada. They hatch from eggs laid in gravel in a river, and spend the first one to two years of their life in freshwater.

When ready they move down the river to the sea, becoming what is known as a “smolt”. They can swim many thousands of kilometres in the Atlantic Ocean searching for food. After a year at sea they begin to mature and become ready to reproduce. At this point they return to the river from where they originated and swim upstream until they reach a suitable place to lay eggs.

This life-cycle of Atlantic Salmon has been continuing around the Atlantic Ocean for millions of years. It is only recently that humans have interfered and tried to farm wild fish in cages on farms.

Cruelty in fish farming

Initially the eggs are raised in a hatchery in small tanks, then transferred to larger growing-on tanks until they become smolts (by which time they are about 70 grams). At this stage they are deprived of feed for 1-2 days prior to being transported to sea cages. This food deprivation and transport invariably causes stress and death in some cases. The pumping out of the transport tank into the sea cage would also be quite stressful.

Additional stress is imposed when these cages are towed from the point of introduction to salt water to the site where they will remain during the ongrowing stage. This can be a distance of up to ten kilometres and there is no feeding during this time. It can take up to half a day to travel just two kilometres, therefore this relocation can take several days. Aquaculture operators keep the towing of cages to a minimum as it is costly to them and, due to the removal of feed, they recognise that the fish are caused elevated levels of stress.

As the fish grow they are graded to sort fast-growing fish from slow-growing ones. This involves sucking them out of the cage, sending them along a race to be sorted, then dumping them into another cage. As much as it is stressful, this process can also be deadly for some fish.

Farmed fish are kept in unnaturally high densities. Fifty thoushand Smolts are kept in an 80m diameter pen, adults are stocked at 40,000 in a 120m diameter pen. At a stocking density (prior to “harvest”) of up to 15 kg/m3, this equates to a 75cm salmon having a space about the size of a bath tub to swim in. Being packed in so tightly they rub against each other and the sides of the cage. This can cause fin and tail damage and lead to disease and infection.

In an attempt to combat amoebic gill disease, Atlantic Salmon are periodically bathed in fresh water. This involves moving the fish out of the cages and into a lined cage of fresh water where they are held for about four hours before being released back into the sea water. In summer this can occur once a month and imposes serious stress in the process of being mechanically moved from saltwater to freshwater and back.

Slaughter of Atlantic Salmon has typically followed “stunning” using carbon dioxide. This is not guaranteed to render the fish unconscious so they may be killed while still very aware. More recent techniques that utilise a percussive captive-bolt stunner are claimed to be humane. Like methods to stun terrestrial animals they are likely to sometimes be ineffective. Conscious animals may be bled to death as a result.

Wasteful practices

The fish species produced in Tasmania are carnivorous, so they are fed on a diet that is largely comprised of fish meal. The meal is made from wild-caught small fish (like herring, mackerel, anchovy and sardine). To produce one kilogram of Atlantic Salmon may take three kilograms of wild caught fish. But Atlantic Salmon are worth much more than fish they are fed on. These fish are not grown to feed the starving masses but sold to lucrative markets in Australia and overseas.

Fish Intelligence

According to Dr Culum Brown of Macquarie University, and co-author of Fish Cognition and Behaviour, in his study released in 2006 fish could be as socially able as monkeys and elephants. Having studied fish for the past ten years, Dr Brown found that they have impressive memories, learn quickly and can teach each other.

In the enclosed space of aquariums they often exhibit abnormal behaviours. These include abnormal feeding, shelter-seeking, bottom-sitting, head-standing and tail-walking. Repetitive behaviours were seen in 90% of the aquariums visited for Dr Brown’s study.

Dr Theresa Burt de Perera of Oxford University in 2004 found that fish construct mental ‘maps’ of their surroundings, and quickly memorise any alterations, putting paid to the idea that goldfish have such short memories that they have forgotten where they have been by the time they swim around their bowl. Of course such ridiculously short memories would make it impossible to survive in a natural environment!

With their high levels of intelligence, fish are just as susceptible to the stresses and traumas of factory farming as land based species.