Fish

Pros

None.

Cons

• Overfishing means wild cod around the UK are not doing well so most are imported.
• They are often caught by “bottom trawling” where weighted nets are dragged across the seabed, which destroys reefs and sea mounts, and leads to a large amount of “bycatch” (catching unintended species like dolphins and rays), while releasing a huge amount of carbon.
• There are no laws to govern what can be done to fish at sea so there is no such thing as humane slaughter.
• The other choice is factory-farmed cod which, given the collapse of wild populations due to overfishing, is now increasing.
• Conditions on fish factory farms are known to be appalling and, as cod in farms eat a huge amount of wild fish, The Scottish Fishermen's Federation says cod farming actually trebles the pressure on the already dwindling wild species.

Pros

None.

Cons

• All “Scottish” salmon sold in UK supermarkets is factory-farmed but the industry’s lawyers made sure they do not need to declare that on the label.
• Flesh-eating sea lice are endemic, making animal welfare very poor.
• To deal with the infestation, as well as all the other parasites, bacteria, and fungal infections, an array of toxic chemicals is routinely used. This includes carcinogenic formaldehyde and chemicals like emamectin benzoate, deltamethrin, and azamethiphos, which are highly toxic to wildlife.
• Antibiotics are often used, which can weaken the efficacy of antibiotics for people.
• Animal welfare scandals on salmon farms are plentiful.
• There is a shockingly high death rate.
• The industry routinely breaks environmental laws.
• And yet still it successfully lobbies to be given large amounts of public money.
• Investigations have shown that even the RSPCA Assured label is no guarantee of acceptable conditions and treatment.

Pros

• Haddock are not generally factory farmed.

Cons

• Wild haddock are often caught by “bottom trawling”.
• This fishing method drags a weighted net across the seabed which tears it up, destroying reefs and sea mounts, leads to a large amount of bycatch (catching unintended species like dolphins and rays), and a massive release of carbon.
• There are no laws to govern what can be done to fish at sea so there is no humane slaughter.
• Concerns over the Marine Stewardship Council’s conflict of interest, the amount of by-catch it overlooks, and the lack of regulations at sea.
• Haddock tend to swim with cod, whose populations are in trouble, which means they get caught too.

Pros

None.

Cons

• You might think of tuna as a wild species, but increasingly, they are being caught in the wild and then kept inside factory farm fattening pens.
• You can avoid factory-farmed tuna by looking for the Marine Stewardship Council certification, although there are concerns over the Marine Stewardship Council’s conflict of interest and the lack of regulation at sea.
• Plus, the fishing methods used to catch tuna often also catch the dolphins who swim with them, as well as other animals, including turtles and sharks.
• There are no laws to govern what can be done to fish at sea so there is no humane slaughter.

Pros

None.

Cons

• Warm-water prawns are factory-farmed, most often in Asia and South America. Deliberately blinding females to increase fertility (eyestalk ablation) is commonplace and the animals may be suffocated to death in ice slurry.
• It is possible to buy ablation-free prawns in some supermarkets, but the animals are still factory farmed and those farms are linked to the destruction of mangroves and the pollution of waters with organic waste, chemicals, and antibiotics.
• Cold water prawns may be slaughtered by suffocation in ice slurry, a method described as “atrocious”.

Pros

None.

Cons

• Most trout sold in UK supermarkets is factory-farmed. Investigations reveal shocking suffering.
• A 2018 investigation found trout flailing about in pools of bloody water after having their throats cut, a clear sign that the stunning system wasn’t working.
• In 2025, investigators found children killing fish at a Cotswold’s trout farm and animals being repeatedly beaten with batons.
• A separate investigation at a Scottish farm found an alarming rate of fish suffocating on ice with traumatic brain injuries after being beaten but not killed.
• Toxic chemicals including azamethiphos and emamectin are used by trout farmers to kill the sea lice that plague farmed fish.
• Farmed trout require a lot of antibiotics and in 2021, used the second-highest volume of highest priority, critically important antibiotics of all animals reared for food.
• Overuse of antibiotics can drive antibiotic-resistant superbugs in people.

Pros

None.

Cons

• Most sea bream and sea bass come from factory farms in Europe.
• A 2018 investigation found 150,000 fish confined to each concrete tank, where disease and parasites thrived. Dead fish were floating in tanks as live ones swam around them. The slaughter process was a horror show, with fish still alive after an hour.
• There is no requirement for humane slaughter and so they are asphyxiated on ice.
• A 2025 report found so many wild fish from West Africa are fed to farmed bream and bass that it is having a negative impact on food security, employment, and even survival for people in that region.