How many fish are killed each year, and how?

The objection

“Fish are different. They’re caught, not really ‘slaughtered’, and anyway it’s a clean, quick end out at sea.”

The answer

Whatever word you use for it, fish are killed in far greater numbers than any other vertebrate, and most of them die slowly. The stunning that humane slaughter rules demand for land animals is rarely used on fish caught at sea, and most farmed fish aren’t stunned either [1][2][3].

How many fish are killed each year?

Roughly one to two trillion wild fish are caught each year, and fish farms kill another 78 to 171 billion for food. Mood and Brooke (2024), who run the fish welfare site fishcount.org.uk, divided the catch tonnages recorded by the UN’s Food and Agriculture Organization (FAO) by estimated average weights for each species, and put the wild catch at 1.1 to 2.2 trillion a year on average from 2000 to 2019 [1]. In 2019 it was lower, 980 billion to 1.9 trillion, because less Peruvian anchovy was landed [1]. By the midpoint estimate, 56% of the wild fish caught in 2010 were ground into fishmeal and fish oil [1]. The farmed estimate, by Mood and colleagues (2023), is for 2019, when fish farms killed nine times as many fish for food as in 1990 [2]. With about 81 billion farmed birds and mammals killed for food in 2019, wild-caught fish alone made up an estimated 87.5% of the vertebrates killed for food or feed [1]. Because catches are recorded by weight and the number of fish has to be estimated, each figure is a range, and the totals leave out fish discarded at sea, illegal and unrecorded catches, fish killed by lost nets, and crabs, prawns, squid and octopuses [1].

How are wild-caught fish killed?

Most wild fish that reach the deck alive are left to suffocate or are gutted while still conscious. Mood and Brooke (2024) write that captured fish face a range of stressors over a process that can last several to many hours; fish still alive when brought aboard are generally not stunned, and die from suffocation in air or ice water or from being gutted alive, which can leave them conscious for up to an hour or more [1]. A review in the Journal of Fish Biology (2009) noted that little, if any, welfare regulation governs how fish are handled or killed in wild-capture sea fisheries [4]. Mood and Brooke, citing the evidence that fish feel pain, call the capture of wild fish a major animal welfare issue [1]. A prototype stunner was tested on wild-caught cod and haddock in 2012 [1]. Yet James and colleagues (2025), reviewing the research on stunning wild-caught fish, say most wild-caught fish still die from suffocation or from being gutted, methods considered inhumane, and found that the settings needed to stun fish humanely have been tested for only a minority of species [3]. In undercover film from a tuna trap at Carloforte, Sardinia, Italy, in 2012, bluefin are hooked aboard and stabbed until they bleed to death.

How are farmed fish killed?

Most farmed fish are killed without being stunned, usually by suffocation in air or in a slurry of ice and water, according to a 2014 review cited by Mood and colleagues (2023) [2]. Their own analysis found that 70 to 72% of the farmed fish killed for food in 2019 had no legal welfare protection at slaughter, and fewer than 1% had protection written specifically for fish [2]. In the UK and the EU, the regulation that requires land animals to be stunned before they are killed sets fish only one rule, its general duty to spare animals avoidable pain, distress or suffering [5][2]. When Mood and colleagues reviewed national laws (2023), Norway required farmed fish to be stunned before slaughter but still allowed live chilling with carbon dioxide, a method that a 2017 study for the European Commission described as being phased out [2]. Switzerland required fish, farmed or wild-caught, to be stunned before killing, though its permitted methods included cervical dislocation, which the World Organisation for Animal Health does not recommend [2]. The 2017 study compared slaughter on fish farms in Norway and some EU countries with that organisation’s guidance, and found widespread failure to follow it across the five species studied, although stunning Atlantic salmon with a blow to the head met it in Norway, the UK and Ireland [2]. Among the methods still in use that fall short of it were carbon dioxide stunning of salmon in Ireland, live chilling of salmon with carbon dioxide in Norway, and suffocation in ice or ice slurry for rainbow trout in Denmark and Poland and for sea bass and sea bream in Greece, Spain, Italy and Turkey [2].