Although the use of animals for food products affects many different species including birds and other animals, the largest number of victims are aquatic animals. The total number of fishes and other aquatic animals caught every year is very difficult to calculate. Measurements are usually made in tons, which makes it impossible to determine the exact number of individual animals killed.

Nevertheless, it is estimated that somewhere between one and three trillion fishes are caught every year,1 and numbers for other aquatic animals could also be extremely high, at least a few hundred billion animals. There is a great variety of fishes and other aquatic animals that are caught, but those that are captured in the highest numbers include sardines, herrings, cods, anchovies, tunas, flounders, mullets, squids, shrimps, salmons, crabs, lobsters, and flatfishes.

The suffering of animals who are caught

We may find it difficult to empathize with fishes and other aquatic animals since they are very different from humans physically, they live beneath the water, and we cannot perceive their vocalizations. However, numerous studies have shown that fishes have the capacity to suffer and feel pleasure, just like mammals, birds, reptiles and other animals.2 Fishes suffer pain and seek out positive experiences.

Just like fishes, amphibians3 and a large number of invertebrates have the capacity to experience suffering and pleasure. Cephalopods such as octopuses have nervous systems very different from those of mammals; however, they are capable of solving problems more complex than those some mammals can solve. This seems to indicate their ability to have even more complex experiences than some mammals, but, more importantly, it means the claim that they aren’t sentient is not plausible.4 And various studies have shown that a variety of crustaceans like lobsters and crabs respond to pain, have biological structures capable of mediating pain, and exhibit cognitive processes that would require enough centralization of the nervous system to be able to feel pain.5 Because animals routinely exploited by humans are sentient beings with the capacity to have positive and negative experiences, the practice of capturing and killing them deprives them of opportunities for enjoyment and causes them significant suffering.

How sea animals who are caught suffer and die

Fishes and other animals who are victims of fishing practices die a variety of ways. They often die due to the decompression as they are hauled up from the depths of the sea to the surface, which causes their internal organs to explode.

Others die of asphyxiation when they are pulled out of the water. Before they die, they experience an enormous amount of distress and make frantic movements as they try in vain to return to the water. Other animals die as a result of injuries from the capturing process or extreme exhaustion caused by stress as they attempt to escape nets (particularly in trawling or trawl fishing). Animals used as bait are also eaten by the animals being captured. And others are crushed by the weight of other fishes being caught with them. This can occur after the nets are collected and emptied or in the fishing nets themselves. Other fishes are killed by fishers, such as tuna, which are killed with spears and other instruments. Many other fishes are frozen alive. On many fishing vessels that are equipped with freezers, animals are immediately put into freezers on board after being caught.

Finally, some of the fishes reach consumers alive and are cooked alive, such as lobsters and crabs. In some cases, some fishes and other sea animals are even eaten alive and conscious.

It is clear from these examples that these animals experience a significant amount of pain as they die. But they also suffer a great deal before dying, because they spend hours or days trapped in nets. They feel a great deal of stress, and they may also have to endure pain if their bodies are crushed up against other animals or scraped against the nets. It is not uncommon for the fishes to sustain many different injuries on their scales, skin, and other tissues. Fishes caught on hooks endure other miseries when they are impaled and trapped by hooks.

Methods of fishing

Net fishing


In trawling, fishing nets are released and then pulled by boats, trapping all the fishes in the vessel’s path. The animals are dragged across the sea floor where they can easily be hit by rocks and rubble, and their bodies bang into the bodies of other fishes. The nets capture all animals in their path that are not small enough to be able to escape from them. The number of animals killed this way at any one time varies a lot, since the sizes of the vessels vary widely.

When fishes are pulled out of the water through trawling, the change in water pressure from rapid ascension bursts their organs. If there are any fishes alive upon reaching the vessel, they are thrown into ice and frozen to death or crushed to death by the weight of other fishes.

Seine fishing

Seine fishing is specifically for capturing animals who swim in large schools like sardines, anchovies, herrings and tunas. In seine fishing, a different type of net is used. The net is cast into the sea by a small boat until it completely encloses the fishes. The net is between 250 and 1000 meters long and about 50 meters wide.

In this method, the fishes are slowly surrounded, and they try to escape but are unable to. There is every indication that this method of capture can cause psychological stress. As the net begins to close in, the animals are crushed against each other, causing injury that worsen until they are pulled from the water.

Drift netting

The fishing nets used in drift netting are made of a fine mesh so they drift with the currents and spread like curtains. They extend over a distance of more than half a mile (one kilometer). The boats let the nets float freely until they are ready to collect the fishes trapped in them. Fishes are unable to see the nets and get hooked in them, often by their gills. The fishes may remain trapped for days until they die. As with other forms of fishing, if they are still alive when they are hauled onto the boat by the fishers, they may bleed to death as a result of the change in pressure, but others are thrown into a freezer alive. To make them more effective, the nets are made out of an odorless synthetic material which is difficult to detect. This ensures that more animals will become victims of the nets.


Trammel is a fishing method in which three different nets are cast at the same time. The interior net is the densest and biggest. Because it is enclosed by the other two nets, it forms bubbles in which the fishes are trapped. It is primarily used to capture animals on the seabed, such as sea bass, common pandora, gilt-head breams, and some crustaceans.

Longline fishing

Longline fishing is one of the most common types of fishing. There are two main types:

  • A fishing vessel casts a fishing line over a long distance, with thousands of baited hooks on the line.
  • A main fishing line is cast with other branch fishing lines tied to it (called snoods) and these branch fishing lines each have hooks attached to them.

When the fishes are caught on hooks, many drown or bleed to death in the water from the wound caused by the hook. Normally a fish is caught by the hook in their mouth, although the hooks can get lodged in other parts of the body. Animals caught in fishing hooks feel more than just the physical pain; they also experience a great deal of stress as they try to escape from the hook before exhaustion causes them to stop struggling.

Larger fishes are attracted to fishing boats by bait. Once they are close enough, the fishers spear or claw the animals, sometimes in their eyes, to be pulled into the boat. Many of these fishes are still alive and are then beaten to death or they bleed to death on their own from having their bodies mutilated. Usually, this method targets animals such as swordfish, tunas and other medium- to large-sized fishes. Sometimes the bait used on these fishing hooks is other smaller fishes who are still alive, so these bait animals are also victims of longline fishing.


Trolling is a method used to capture fishes living near the surface, such as salmons. It uses various fishing lines with bait kept submerged at a fixed depth. The fishing lines can be cast from a fixed spot or tugged by a boat at a slow speed.

The fishes caught by these lines are often dragged along by the boat for a long time, which can be extremely stressful and painful. Moreover, many of the animals caught this way can be hooked by parts of their body other than their mouths, causing fatal injuries, especially if they are caught by the gills.

Other fishing methods

In addition to the methods mentioned above, which are common in many parts of the world, there are different techniques used only in particular locations or to capture certain types of animals.6

Fishing with explosives

This fishing method consists of discharging explosives into the water. The explosives can directly kill the animals or make them easy to catch after they are stunned by the explosions. The explosives can also cause the fishes’ air bladders to explode; without air bladders, fishes can no longer swim and they will sink to the bottom of the sea. They might be captured before they sink. This method is used extensively in south-east Asian countries, especially in the Philippines, and also in Thailand.

Fish traps

At times, fishes and other sea animals are caught using simple traps consisting of cages in which bait (such as a live animal) is placed to attract the animals that are to be caught.


The almadraba fishing practice is typical of the Mediterranean region, used in places like Italy and the south of the Iberian Peninsula. Its objective is to catch tunas by luring them into a very confined space where they have very little space to swim. They are led through pathways created by nets of different curvatures in such a way that they are able to reach the center but unable to find the way back to escape. Fishers bring the trapped tunas on board with hooks and then kill them with knives or machetes.

Animals killed for nothing: “bycatch”, “over-quota” and abandoned nets

A large number of the animal victims of fishing activities are not eaten.7 Many animals who are not intended to be caught are trapped anyway. The number of different types of animals who can die this way is quite large and includes invertebrates, fishes, seabirds, turtles, and dolphins.8 Some of these dead animals are sold; however, others are thrown away because they are of no economic value. An example is the large number of albatrosses who die every year after getting trapped in the longline fishing hooks to which they are attracted by the bait.

In other cases, fishers have a legal quota of fishes they are allowed to catch, so they throw back any that exceed the limit. The majority of these animals suffer greatly and die anyway from their injuries.9

In addition, fishing nets, or parts of them, are often lost or abandoned in the water. These nets continue indefinitely killing the animals who get trapped in them.10 The trapped animals can experience a great deal of stress before they die due to hunger or asphyxiation.

In this way, fishing has many more victims than those caught and sold for human consumption.

The solution is not fish farming or sustainable fishing, but abandoning the exploitation of aquatic animals

Fishing causes an enormous amount of suffering and the death of trillions of animals every year. In order to respect all conscious beings, those who have the capacity to suffer and feel pleasure, fishing in any form cannot be acceptable. Supporters of fish farmers claim that the solution lies in fish factories. However, this cannot be a solution since fish farming also involves the killing of animals and causing suffering to them.

So-called sustainable fishing has also been suggested as a solution to various fishing methods, and numerous environmental management studies of fishing banks have been done. This is often done from an environmentalist point of view. At times there are protests against certain forms of fishing, with the argument that there shouldn’t be an “over-exploitation” of the so-called “fishing resources”. This implies trying to continue to use animals indefinitely, who are considered, as the name itself suggests, simply resources. This attempts to satisfy the economic interests of continuing to live off fishing, which is unacceptable from an ethical perspective if we reject speciesism.

This ecological point of view does not take into account the interests of fishes; instead it defends an “ecological management” of fishing, with systems in place to make some fishes prey to others in a controlled manner. If we look at from an antispeciesist perspective instead, we will consider the interests of all sentient animals and will regard these activities totally unacceptable because of the harm done to the animals when they are captured and killed, as well as the harm caused by making them kill and eat each other.

Environmentalists sometimes try to protect members of endangered species at the expense of members of more numerous species. This practice must be rejected from an ethical perspective because an individual doesn’t deserve more or less respect depending on how many members there are of their species. The problem with fishing is not the diminishment of resources, or the endangerment of species, as environmentalists and those who view aquatic animals as resources claim. The problem is the suffering and death caused to conscious creatures for unnecessary reasons. Since humans do not need to eat fish, to catch them for leisure, or to use their bodies as ornaments, fishing cannot be considered necessary. Therefore fish farms and sustainable fishing are not solutions, since they still cause pain, anxiety, and, ultimately, the premature death of conscious creatures.

Further readings

Ashley, P. J. & Sneddon, L. U. (2007) “Pain and fear in fish”, in Branson, E. J. (ed.) Fish welfare, Oxford: Blackwell, ch. 4.

Braithwaite, V. A. & Huntingford, F. A. (2004) “Fish and welfare: Do fish have the capacity for pain perception and suffering?”, Animal Welfare, 13, pp. 87-92.

Caswell, H.; Brault, S.; Read, A. J. & Smith, T. D. (1998) “Harbour porpoise and fisheries: An uncertain analysis of incidental mortality”, Ecological Applications, 8, pp. 1226-1238.

Catchpole, T. L.; Frid, C. L. J. & Gray, T. S. (2005) “Discards in North sea fisheries: Causes, consequences and solutions”, Marine Policy, 29, pp. 421-430.

Chandroo, K. P.; Yue, S. & Moccia, R. D. (2004) “An evaluation of current perspectives on consciousness and pain in fishes”, Fish and Fisheries, 5, pp. 281-295.

Dunlop, R. & Laming, P. (2005) “Mechanoreceptive and nociceptive responses in the central nervous system of goldfish (Carassius auratus) and trout (Oncorhynchus mykiss)”, The Journal of Pain, 6, pp. 561-568.

Erickson, H. S. (2003) “Information resources on fish welfare: 1970-2003”, Beltsville: U. S. Department of Agriculture [accessed on 13 April 2022].

Gabriel, O. & von Brandt, A. (2005) Fish catching methods of the world, Oxford: Blackwell.

Gilman, E.; Brothers, N.; McPherson, G. & Dalzell, P. (2006) “A review of cetacean interactions with longline gear”, Journal of Cetacean Research and Management, 8, pp. 215-223.

List, C. J. (1997) “On angling as an act of cruelty”, Environmental Ethics, 19, pp. 333-334.

Mazeaud, M. M.; Mazeaud, F. & Donaldson, E. M. (1977) “Primary and secondary effects of stress in fish: Some new data with a general review”, Transactions of the American Fisheries Society, 106, pp. 201-212.

Morizur, Y.; Berrow, S. D.; Tregenza, N. J. C.; Couperus, A. S. & Pouvreau, S. (1999) “Incidental catches of marine-mammals in pelagic trawl fisheries of the northeast Atlantic”, Fisheries Research, 41, pp. 297-307.

Pauly, D. & Zeller, D. (2016) “Catch reconstructions reveal that global marine fisheries catches are higher than reported and declining”, Nature Communications, 7 [accessed on 25 January 2016].

Rose, J. D. (2002) “The neurobehavioral nature of fishes and the question of awareness and pain”, Reviews in Fisheries Science, 10, pp. 1-38.

Sneddon, L. U. (2003) “The evidence for pain in fish: The use of morphine as an analgesic”, Applied Animal Behaviour Science, 83, pp. 153-162.

Sneddon, L. U.; Braithwaite, V. A. & Gentle, M. J. (2003) “Novel object test: Examining nociception and fear in the rainbow trout”, The Journal of Pain, 4, pp. 431-440.

Tasker, M. L.; Camphuysen,C. J.; Cooper, J.; Garthe, S.; Montevecchi, W. & Blaber, S. (2000) “The impacts of fishing on marine birds”, ICES Journal of Marine Science, 57, pp. 531-547.

Wade, P. R. (1998) “Calculating limits to the allowable human-caused mortality of cetaceans and pinnipeds”, Marine Mammal Science, 14, pp. 1-37.

Wall, A. J. (2001) “Ethical considerations in the handling and slaughter of farmed fish”, in Kestin, S. C. & Warriss, P. D. (eds.) Farmed fish quality, Oxford: Fishing News, pp. 108-115.

Zerbini, A. N. & Kotas, J. E. (1998) “A note on cetacean bycatch in pelagic driftnetting off Southern Brazil”, Report of the International Whaling Commission, 48, pp. 519-524.


1 Mood, A & Brooke, P. (2024) “Estimating global numbers of fishes caught from the wild annually from 2000 to 2019”, Animal Welfare, 33, e6 [accessed on 11. Mai 2024].

2 Chandroo, K. P.; Duncan, I. J. H. & Moccia, R. D. (2004) “Can fish suffer?: Perspectives on sentience, pain, fear and stress”, Applied Animal Behaviour Science, 86, pp. 225-250. Braithwaite, V. (2004) Do fish feel pain?, Oxford: Oxford University Press.

3 Machin, K. L. (1999) “Amphibian pain and analgesia”, Journal of Zoo and Wildlife, 30, pp. 2-10.

4 Mather, J. A. & Anderson, R. C. (2007) “Ethics and invertebrates: A cephalopod perspective”, Diseases of Aquatic Organisms, 75, pp. 119-129. Mather, J. A. (2001) “Animal suffering: An invertebrate perspective”, Journal of Applied Animal Welfare Science, 4, pp. 151-156.

5 Elwood, R. W. (2011) “Pain and suffering in invertebrates?”, ILAR Journal, 52, pp. 175-184. Elwood, R. W. & Adams, L. (2015) “Electric shock causes physiological stress responses in shore crabs, consistent with prediction of pain”, Biology Letters, 11 (11) [accessed on 13 November 2018].

6 Many other fishing methods exist. Common examples include angling, hand-net fishing and spearfishing. These methods are used for leisure fishing as well as for catching fishes for human consumption. Another method is cyanide fishing, in which cyanide is used to stun fishes in order to capture them live for ornamental purposes.

7 This takes into account the fact that a significant proportion of the fishes used are not for human consumption, but for breeding other animals, including many who are bred in fish farms: Tacon, A. G. J. & Metian, M. (2009) “Fishing for aquaculture: Nonfood use of small pelagic forage fish, a global perspective”, Reviews in Fisheries Science, 17, pp. 305-317.

8 Fitzgerald, K. T. (2013) “Longline fishing (how what you don’t know can hurt you)”, Topics in Companion Animal Medicine, 28, pp. 151-162.

9 Alverson D. L.; Freeberg, M. K.; Murawski, S. A. & Pope, J. G. (1996 [1994]) A global assessment of fisheries bycatch and discards, Rome: Food and Agriculture Organization of the United Nations [accessed on 22 July 2014]. Hall, M. A. (1996) “On bycatches”, Reviews in Fish Biology and Fisheries, 6, pp. 319-352. Demaster, D. J.; Fowler, C. W.; Perry, S. L. & Richlen, M. E. (2001) “Predation and competition: The impact of fisheries on marine mammal populations over the next one hundred years”, Journal of Mammology, 82, pp. 641-651. Brothers, N. P. (1991) “Albatross mortality and associated bait loss in the Japanese longline fishery in the Southern Ocean”, Biological Conservation, 55, pp. 255-268. Read, A. J.; Drinker, P. & Northridge, S. (2006) “Bycatch of marine mammals in the U.S. and Global Fisheries”, Conservation Biology, 20, pp. 163-169.

10 Parker, C. (2017) “‘Pair trawling’ blamed for death of sea mammals”, Irish Examiner, 12 Jan [accessed on 20 January 2017].