Introduction to the problem and scale

Wild fish live free, but the methods of capture and processing are often industrial, with no considerations for their welfare; the potential for suffering is therefore huge.

• In 2022, 78 million tonnes of fish were caught from the wild, consisting of between 940 billion and 1.9 trillion individual fish¹. This compares with around 80 billion terrestrial animals slaughtered for food each year².
• The vast majority of fish stocks are considered by the FAO to be overfished (37.7%) or fully exploited (~50%)³.
• By tonnage, around 20% of these wild caught fish are  ground down to fishmeal and oil each year⁴. However as the fish used are so small, it is a much higher percentage in terms of numbers of individuals – around half are used for this purpose instead of being eaten directly by people⁵. Most fishmeal and oil is used as ingredients in farmed fish feeds.
• Wild-caught fish typically die from injuries during capture and landing, or from asphyxiation (suffocation) in air, on ice or in iced-water⁶ when on board, and they may be bled by the gills without pre-stunning. These are all methods which the World Organisation for Animal Health acknowledges to result in poor fish welfare⁷.^.
• Many wild fish are processed - for example, gutted - whilst still alive. One Dutch study which examined fishing for herring, cod, whiting, sole, dab and plaice, showed that the fish took 55-250 minutes to die from asphyxiation. Those who were gutted first remained conscious for 25-65 minutes⁸.
• Cephalopods such as octopus and squid and decapods such as lobster, crabs, and prawns, are also caught in enormous numbers not yet estimated. According to EFSA, there is good evidence for sentiency in these creatures⁹. Cephalopods may be left to die en masse in a net or other container, sometimes chilled; or killed with blunt trauma, mantle inversion, or through damage to the brain¹⁰.

Higher welfare alternatives

More humane methods of capture and slaughter of wild fish are being developed, though currently their use is very rare.

Traditional methods of stunning before slaughter include mechanical stunning (e.g. a blow to the head) or spiking (where the brain is destroyed with a sharp instrument)¹¹. The latter is used in the production of sashimi since the reduced stress to the fish results in better flesh quality.

Some modern trawlers use electrical systems to immobilise fish for health and safety reasons (fish that are not struggling are safer for workers to process), to ensure higher quality, or more accurate filleting¹². However, even though fish may be immobilised they may still be conscious and able to feel pain. These systems could be adapted to deliver an effective stun¹³.

How are wild fish affected by factory farming?

Given that many of the fish species farmed are carnivorous, fish farming is a major driver of the sheer numbers of wild-caught fish disappearing from our oceans.

• Around 17 million tonnes (22% in weight) of all wild fish caught in 2022 were landed specifically for reduction to fishmeal and oil, the great majority of it used for farm animal feed¹⁴. This consists of around 0.5-1 trillion fish. The actual number may be higher since many fisheries are indiscriminate in their catches¹⁵.
• According to industry figures, 75% of fish oil is used in aquaculture feeds¹⁶, 70% of fishmeal is used in aquaculture, while over 22% is used in pig feed and 6% in chicken feed¹⁷.
• Feeding wild caught fish to farmed fish is extremely wasteful and inefficient, as it results in less food for people overall. When fishmeal is fed to farm animals, 60-86% of the protein content is likely to be lost to the human food chain. According to one study, only 28% of the protein fed to farmed salmon ends up in human-edible food¹⁸. The study also calculated figures for chickens (37%), pigs (21%), trout (22%), whiteleg shrimp (22%), pangasius (17%) and giant tiger prawn (14%), all of whom may consume fishmeal in their diet, especially the fish and crustaceans.
• 90% of fishmeal and oil comes from food-grade species¹⁹ which means they can be, and are, eaten by people. Farm animals, including farmed fish, are competing with people for food and wasting valuable resources.
• Fishmeal production is mainly sourced from forage (i.e. low in the marine food chain) fish species that play a vital role in ecosystems. This means that huge numbers of fish are taken from the seas that would otherwise be food for large fish, marine mammals and seabirds, putting their populations at risk²⁰.
• The inclusion of fishmeal and oil in the diet has potential negative health consequences. Examples would be the transfer of toxic substances such as PCBs, dioxins, and pesticides into farmed fish²¹; antibiotic resistance genes and human potential pathogenic bacteria have been found in fishmeal samples²²; and fish feed may be contaminated with microplastics²³.

 

Reducing overfishing 

Taking the pressure of wild fish populations and catching considerably less fish is essential for the future health of our oceans. Reducing the activity of industrial fisheries worldwide would have many benefits.

• Allowing fish stocks to recover means giving marine life the chance to thrive, in addition to the human communities that depend on them. In particular, avoiding industrial catches off Africa would leave more fish for small-scale fishers and direct human consumption.
• Lowering fishing carbon emissions by reducing the energy expended.
• Allowing fish to grow larger before they are caught which means less animal suffering per tonne of fish caught.

Supporting the development of humane capture and slaughter techniques is likely to improve the quality of the product, by reducing stress and injury. This would also prevent suffering for hundreds of billions of fish during the slaughter process each year.

Link to the relevant Sustainable Development Goal (SDG)

• SDG 14: Life below water. Conserve and sustainably use the oceans, seas, and marine resources for sustainable development^24.