Is it ethical to buy farmed fish?

The commercial farming of aquatic animals and plants is known as aquaculture. It involves mass-breeding aquatic organisms in human-made environments under controlled conditions. Aquaculture as an industry evolved due to the rise in consumer demand for fish, prawns, and other sea creatures. In less than 50 years, aquaculture has become bigger than cattle farming and is the world's fastest-growing agriculture sector with projections suggesting it will become even bigger. But is this industry ethical? The demand for sea animals is having a massive, negative impact on animals, the environment, and human health – let’s dive in.

What is aquaculture?

Fish farming occurs on land and in the ocean. Land-based aquaculture uses tanks or ponds that can be found inland or along the coast. These systems can either be fully enclosed or partially open to release wastewater. Inland systems allow producers to manipulate fish into spawning outside of their normal breeding season by controlling the temperature and light to maximise profit.

Ocean systems use large netted enclosures that float in the water, known as sea-cages. Other ocean systems include stick, rack or line aquaculture. These are structures suspended in water or along the seafloor that are used to farm shellfish, like oysters.

Why is aquaculture unsustainable, cruel, and harmful to human health?

Farmed fish are fed wild-caught sea animals – contributing to the over-exploitation of the ocean

Most species of farmed fish and crustaceans are carnivorous, which means that additional fish must be caught from our already-exhausted oceans to feed them. This makes aquaculture unsustainable. It is estimated that 37% of all global seafood is now ground into fish feed. In many instances, the industry catches small fish near the bottom of marine food webs, which is a notoriously unsustainable source. These fish are critical in maintaining the health of the ocean. Taking them out to feed other fish is a recipe for environmental disaster.

On top of this, animals eat more than they produce. Bluefin tuna require approximately 57.3 kilograms of fish from the ocean to produce just 2 kilograms of farmed bluefin tuna! Every kilogram of salmon or prawns can use up 2.5-5 kilograms of wild fish as feed. Aquafarmers are even feeding fish oil and fish meal to herbivorous fish (who are only supposed to eat plants) to make them grow faster and become more profitable. Additionally, farmed fish can be fed ground-up land animals from other farms, mixed with fish caught from trawlers. As mentioned on the “Chicken Farming” issues page, animal by-products are collected and rendered into animal feed. Cows, chickens, pigs, ducks, and lamb, are unnatural food sources for fish and can have a potential impact on them.

Some species of fish, such as tuna, are difficult to breed in captivity. As a result, the most common method of farming tuna is by catching juveniles in the wild, transferring them to ocean or land cages, and killing them when they reach a profitable weight. This does nothing to reduce pressure on wild populations, as it is removing young tuna from the oceans - who are vital for the species' survival.

Fish farming is cruel

All available evidence suggests that there are serious welfare concerns for fish in aquaculture industries. These concerns exist at all stages of the production cycle. During the first stage, the mature fishes used to provide the eggs for the farm are “stripped”. This process involves workers literally squeezing their bodies to “milk” the eggs and sperm that are used to breed more fish for people to eat. 

Farmed fish spend their entire lives in crowded and filthy enclosures. These farms can be as big as ten football fields put together, and often contain more than 1 million fish. While stocking densities vary, there can be up to 400,000 prawns per hectare. They spend every single minute of their life unable to move freely, only to suffer a long and painful death.

Farmed fish suffer from deformities, diseases, and illnesses – posing risks to wild fish

The cramped enclosures they live in inhibit their ability to move and cause them to knock against each other. As a result, many fish suffer from injuries and deformities, such as blindness, ‘eye pop’, lower jaw deformity syndrome, gaping jaws syndrome, skin lesions, fin damage, bacterial infections, and parasitic infections. One common parasite disease with a high mortality rate is amoebic gill. These illnesses and diseases can spread to wild fish populations when wild fish swim past the farms or fish escape the farms. As water temperatures rise due to the climate crisis, this disease is especially concerning.

Farmed fish are also selectively bred and they consequently have less genetic variation than wild fish. When they escape into the wild and interbreed with wild fish, this causes the formation of a less genetically diverse population. It can even result in infertile offspring, which doesn’t help the existing state of population decline due to overfishing. This poses a threat to many fish species because a less robust population is prone to environmental pressures such as disease and natural disasters.

Farmed fish are severely depressed

Though the environmental impacts of aquaculture are significant, the suffering experienced by the fish these industries produce is equally concerning. Like animals farmed on land, the lives that farmed fish lead are unnatural. And just like factory-farmed mammals, they are denied any ability to engage in natural or normal behaviours. They are either bred as future food for humans or taken from the wild to be fattened in cramped cages. This has profound impacts on individual fish. Despite this, fish welfare remains relatively ignored. Though fish possess similar qualities to other mammals and birds, their capacity to suffer has been “ignored, avoided or actively rejected until very recently”. 

In 2016, researchers examined the brains of sluggish, stunted salmon on farms, and found sky-high measures of the stress hormone cortisol. They found one in every four salmon suffers the same way stressed and depressed people do. Their serotonin levels mirrored those of depressed mammals. Studies have shown that stress can make fish likelier to experience disease and other issues associated with captivity. These aquatic animals are treated like biological machines when we know they are sentient beings with intelligence and rich social lives.

Fish feel pain and experience fear

Fish, like all animals, have specialised receptors - known as nociceptors - that detect any damage and allows them to react. Some of these reactions trigger stress. Studies have proven that fish have these special receptors.  Fish who have experienced pain, react and change their behaviour. Studies show that they eat less, rub the affected area, and their "opercular beat" (similar to our respiratory system) rate increases. Like us, they also learn to avoid what caused them pain in the future. 
There is also ample evidence showing that they also feel fear. Australian professor Culum Brown, who is a world-renowned expert on fish welfare, says that their intelligence is “on a par with most other vertebrates”. And because they have the ability to suffer in a way similar to other animals, it is clear that fish are sentient.

Fish suffer when they are killed for human consumption

Despite knowing that fish feel pain and experience fear, they are often excluded from any protection and welfare laws. When the fish become most “profitable”, they are killed by asphyxiation (suffocation by taking them out of water), which can take up to several hours, are exposed to carbon dioxide or very low temperatures, or are bled out. All of these methods cause immense pain and suffering.

Wild animals are killed to “protect” farmed fish 

Ocean fish farms are known to attract predatory marine animals, such as seals, sea lions, sea birds, and sharks. As a result, some producers fire beanbag bullets at seals or use explosives to deter the animals. Seals have been blinded, deafened, and killed as a result. In just three months, the Tasmanian salmon industry has used more than 2,400 anti-seal explosives and 70 bean bag rounds, killing at least two seals who should be legally "protected" under law.

Aquaculture pollutes the environment

Fish farming generates an immense quantity of waste that affects the environment and ecosystem. A 2-acre salmon farm is said to produce as much waste as a town of 10,000 people. Water contaminated with faeces, food waste, and dead animals from aquaculture industries mixes with the surrounding water, polluting the environment. In some land-based systems, wastewater can enter the surrounding environment or be used as fertilizer, entering rivers and streams or even the sea. In all instances, this can cause nitrogen pollution and oxygen depletion, killing wild fish in the area.

On top of this, significant doses of antibiotics and other chemicals are used in aquaculture to decrease the spread of disease. Using these substances can also harm wild marine animals. Even though there are no antibiotics registered to use in the Australian aquaculture industry, there is “significant off-label use”.

Globally, as much as 50% of methane emissions come from aquatic ecosystems. Coastal aquaculture farms can emit over 400 times more methane per area than coastal habitats, such as mangroves and marshes.

Aquaculture poses risks to human health

The use of antibiotics in aquaculture has the potential to create antibiotic-resistant diseases, which can spread from animal to human pathogens. The use of chemicals and antibiotics also results in dangerously high levels of PCB and dioxin in farmed fish, which can pose serious health risks to people who eat seafood.

Help sea life by leaving fish off your plate

Fish not only feel pain, but they are also a lot smarter than many people believe. Some of their cognitive powers surpass those seen in “higher” animals, such as primates. Many of the main features of a fish's biology are the same as ours. In fact, many of their senses are better than ours. Australian scientist Culum Brown has shown that fish have exceptional memories and live in underwater communities where they learn from, cooperate with, and recognise each other. They also solve problems and even invent tools.

Choose to leave fish and other sea creatures off of your plate. By eating plant-based alternatives you are not only saving lives but also helping end the demand, creating a kinder world for sea animals.

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