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Fish Welfare in UK Wild Caught Fisheries

Updated: Aug 15, 2023

EXECUTIVE SUMMARY

Wild caught fishing is distinguished both by the huge number of animals affected and by the complete neglect of their welfare during slaughter. Fish suffer from numerous sources of harm during wild capture, including injuries from hooks and nets, injuries from changes in pressure, asphyxiation, injuries from being out of water, gill cutting, and live gutting.


Above even the horrors of land animal agriculture, fishing is distinguished by the extreme brutality of the ways the animals are killed. While during slaughter, a farm animal might suffer acutely over a period of seconds or minutes, fish may suffer for hours or even days in some cases. This long duration might lead one to expect that their suffering is less acute, but in fact they are injured in a variety of ways during the capture process and can be said to be dying from many causes at once. This suggests that their deaths involve a tremendous amount of suffering.


Legislation currently provides no protection against these horrors, as these animals are specifically excluded from even the minimal protection of the Animal Welfare Act (DEFRA, 2006a). This means that there is not even a requirement to minimise their suffering – let alone any specific legislation regarding best practises for their welfare – such as the Welfare of Farmed Animals (England) Regulations or a specific Code of Practice (DEFRA, 2006b). Therefore, the largest group of vertebrate animals slaughtered for their meat in the UK are also the group that have essentially no protection under the law.


Despite this striking exception, the UK government is considered a world leader in animal welfare. Working on animal welfare in the UK might therefore serve as encouragement for other countries to begin to follow suit.


Despite the massive scale and neglect of the topic, wild caught fishing has received relatively little attention from animal advocates, though this is starting to change following the release of the extremely popular Netflix documentary, Seaspiracy. Work on this subject is difficult because of the lack of technological and economic feasibility of many welfare reforms, as well as a lack of research. However, we think some exploratory work on this subject would be valuable.


Work on this subject would begin with an ask - for example, preferentially catching larger fish or banning bottom trawling - that is motivated by an environmental angle. There is great benefit to beginning work on the subject, and the potential for many more important asks to come. Most prominently, advocates can work towards requiring stunning before slaughter, though we are currently far away from achieving that. We are eager to speak with any organisation considering starting work on the subject to help them more confidently identify priorities in this area. Though this report is focused on the case of the UK, many parts of this report also apply to fisheries and other countries.


OVERVIEW OF UK FISHERIES

Including numbers caught in the waters of the territories, the UK caught 702,000 tonnes of fish in 2018 with an additional 194,000 tonnes coming from aquaculture (Marine Management Organisation, 2019; World Bank, no date). This is slightly more than 1% of the global total in 2018 of 96.4 million tonnes (FAO, 2020). This is estimated to represent between 1,526,000,000 and 2,683,000,000 individual fish (Mood and Brooke, 2019). This number is larger than the number of vertebrate animals farmed in the UK (including aquaculture) (Garrett and McCulloch, 2022). In addition, an estimated 46 million fish were caught by British sea anglers in salt water alone (Marine Management Organisation, 2021). This number is roughly estimated based on average species weight and the tonnage of fish caught because individual data is not kept on the subject. The fleet size of the UK is the second largest in the EU by tonnage (Marine Management Organisation, 2021).


Of this amount, a survey of fishing vessels in 2020 found that the most common species in UK marine fisheries are Atlantic mackerel (205,000 tonnes), Atlantic herring (75,000 tonnes), Blue whiting (52,000 tonnes), Haddock (29,000 tonnes), Atlantic cod (25,000 tonnes), and shellfish (tonnage unavailable, but mostly nephrop lobsters, crabs and scallops) (Seafish, no date; Billington and Kirsch, 2021). Overall, 37% of the catch is shellfish, and of the remainder, 36% is fish taken from the demersal zone (bottom of the ocean) and 28% is fish taken from the pelagic zone (the open ocean) (Marine Management Organisation, 2019). Freshwater fishing accounts for a negligible proportion of this amount (Billington and Kirsch, 2021). Despite its much smaller population, Scotland dominates UK fisheries with 64% of the total catch, compared to 26% for England (Marine Management Organisation, 2019).


This catch is statistically top heavy with vessels over 12m responsible for 83% of total catch by tonnage, despite only accounting for 327 out of a total of 3,078 vessels (DEFRA, no date). It may be promising to focus on welfare reforms for these larger vessels, where they may be easier to implement. Two thirds of the quota is held by 25 corporations, suggesting that corporate campaigns could also be a possibility (Dowler, 2018).


Because of its long coastline and many overseas territories, the UK has an outsized exclusive economic zone that includes fishing rights, comprising the fifth largest in the world (Migiro, 2018). Some of this area is currently shared with the EU, with the EU catching 739,000 tonnes in the UK exclusive economic zone in 2020, a similar number to the total caught by UK fishers (Marine Management Organisation, 2021). The UK in turn Catches 15% of its total fish cash in EU waters (Garrett and McCulloch, 2022). This may change after future negotiations in the process of transitioning away from involvement in the EU; however, there are suggestions this may not happen as these rights may be surrendered as a compromise in future trade deals (Phillipson and Symes, 2018; Kay, 2021). Fishers from other countries must follow UK standards while fishing in UK waters, which means that many additional fish would be protected by any UK legislation that directly or indirectly improves fish welfare (Phillipson and Symes, 2018). This is a significant reason for focusing on a country with a large exclusive economic zone such as the UK.

Source: UK Sea Fisheries Annual Statistics Report 2020


Including aquaculture, the UK has been a net importer of fish since 1984 (Kay, 2021). In 2020, the UK imported 672,000 tonnes of fish and exported 423,000 tonnes of fish. The total import value was approximately double the export value (Marine Management Organisation, 2021). Approximately 80% of UK fish exports are exported to the EU (Kay, 2021). Consumption of Cod, haddock, tuna, salmon and prawns represents 60% - 80% of domestic fish consumption in the UK (Marine Management Organisation, 2021).

This number also excludes bycatch, nontarget species that are incidentally caught in the fishing process. The rate of bycatch is approximately 50% by weight in the North Sea on the East coast of the UK (Cook, 2003; BBC, 2007). Even when bycatch animals are returned to the ocean, their chances of survival are poor (Waley et al., 2021).


OVERVIEW OF CURRENT PROTECTIONS


Current legislative protection

There is currently no animal welfare legislation that applies to wild caught fish in the UK. The Animal Welfare Act – the primary and most basic piece of legislation governing the treatment of animals in the UK – explicitly excludes anything that happens to fish in the “normal course of fishing”:

216. This section provides that anything which occurs in the normal course of fishing is not covered by this Act. A fish may be a protected animal if under the control of man. The effect of this exception is that, where a fish is under the control of man in the course of fishing, the Act has no application to anything that happens to the fish in the normal course of fishing. So, for example, whilst they are normal fishing practices the use of livebait and the practice of catch and release will not be subject to the Act.”


The Animal Welfare Act introduces a duty to minimise unnecessary suffering, as well as some slightly more specific protection in the form of the five needs:

(1) A person commits an offence if he does not take such steps as are reasonable in all the circumstances to ensure that the needs of an animal for which he is responsible are met to the extent required by good practice.

(2) For the purposes of this Act, an animal's needs shall be taken to include—

  1. its need for a suitable environment,

  2. its need for a suitable diet,

  3. its need to be able to exhibit normal behaviour patterns,

  4. any need it has to be housed with, or apart from, other animals, and

  5. its need to be protected from pain, suffering, injury and disease.

Normally animals are protected by more comprehensive and detailed legislation on top of the Animal Welfare Act, such as The Welfare of Animals at the Time of Killing (England) Regulations 2015 and a specific Code of Practise, but welfare during fishing is so low that even the minimal protections of the Animal Welfare Act might disrupt the industry.

  1. Because of the qualifier "normal", fishing activities that are regarded as abnormal could bring the fish affected under the Animal Welfare Act. This could be a potential campaign angle that should be considered, but, unfortunately, normal fishing activities totally neglect fish welfare, so it is unclear if this could successfully be used as a point of leverage or perhaps as a judicial review once more progress has been made (Collinson, 2018).

Though wild caught fish overall have almost no legal protections, some particularly low welfare fishery practices are already banned in the UK. In Scotland, the Aquaculture and Fisheries (Scotland) Act of 2007 bans the use of live vertebrate bait (including fish), gaffing, and foul hooking (attempting to hook a fish in an area other than their mouth) (Mood, 2010). The import or export of shark fin products was also recently banned in the UK and the practice of removing the fins from live sharks has been banned in UK waters for some time (DEFRA, 2021b). The main reason for this ban seems to have been conservation, but note that the animal welfare minister, Lord Goldsmith, also defends the ban on the grounds that the practice is “indescribably cruel and causes thousands of shark to die terrible deaths” (DEFRA, 2021b). This demonstrates that some low welfare practices may be banned even though wild caught fish are not included in the Animal Welfare Act.

However, though animal welfare is mentioned in the verbal justification for these bans, the primary justification seems to be environmental. Similar bans on environmental grounds but with welfare benefits might be possible, such as a ban on trawling.

As a devolved parliament, Scotland has a separate, but similar welfare act called the Animal Health and Welfare (Scotland) Act 2006 (Scotland, 2006). This act tends to closely follow the Animal Welfare Act that applies in England and Wales (and sections 46-50 of that Act do apply in Scotland), but divergences are possible. If the exception for fishing activities were removed in the Animal Welfare Act of England and Wales, they might well follow suit with the Scottish act, but not necessarily (Collinson, 2018). This should be kept in mind by organisations working on this, and it is possible that it could be better for an organisation to work on the Animal Health and Welfare (Scotland) Act 2006 because of the relatively higher amount of fishing in Scotland. Similarly, a separate act also applies in Northern Ireland.


The Animal Welfare Act only applies to animals under human control. This might be thought to naturally exclude wild caught fish, but as these animals are temporarily under human control, they would otherwise be covered by the Act. A precedent for this is the capture of mice and rats. While living in the wild, the Animal Welfare Act does not apply to them, and killing is permissible, but once they are captured alive it begins to apply to them, and many ways of harming them are no longer allowed (UFAW, no date). Fish are similarly captured alive before slaughter and so the animal welfare act should naturally apply to them.


A BBC news article (BBC, 2004) explains that this exception was added in later by a group of MPs who are concerned that anglers might be prosecuted with the act as written. Unfortunately, the exception also applies to commercial fishing as well. In explaining the decision, the committee responsible added; "However, in exempting fishing, the government should be careful to ensure that those persons who catch fish are not given 'carte blanche' to inflict unnecessary suffering in the course of pursuing this activity”. It is good to hear some mention of this by the UK Government, but unfortunately there has been essentially no protection of wild caught fish, and carte blanche might indeed be a good description of industry standards on this.


One lesson from this is that private anglers represent a substantial lobby, probably a more substantial lobby than the commercial fishing industry. It could be in an campaigning organisation's strategic interest to only focus on commercial fishing, though in this case it would rightly be seen as arbitrary to focus only on commercial fishing (interview proceedings).


REVIEW OF WELFARE EVIDENCE


Capture methods

The main ways fish are caught are trawling or dredging, hook and line, hanging nets, seine nets, and traps (Waley et al., 2021). 87% of fish caught by UK fishers are caught using active methods which includes trawling, dredging, and seine nets. Passive methods including hanging nets, hook and line fishing, and traps make up the remaining 13% (Marine Management Organization, 2020). Fish welfare is jeopardised in a number of ways during all these methods of capture, though some may provide relatively higher welfare. Mortality rates (which is a proxy for amount of suffering) is highest in trawling and purse seines, and lower in hanging nets, hook and line, and traps (Veldhuizen et al., 2018).


Injury sustained during capture and prior to slaughter

Fish will struggle vigorously to escape when trapped in a net, hooked on a line, or brought on board the ship, potentially leading to extreme exhaustion. The oxygen debt incurred by this worsens the asphyxiation that fish are subject to when brought on board (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020). In addition, both stress and exhaustion are particularly dangerous for fish. Fish will normally spend 15% to 20% of their energy budget on maintaining osmotic homeostasis. When they are stressed or exhausted, they may be unable to maintain this energy expenditure and begin to lose water. This can become lethal, as one experiment found that 40% of trout perished from six minutes of exhaustion (Gregory and Grandin, 1998).


Another cause of serious injury and suffering to fish is damage from decompression and barotrauma. Fish rely on a gas-filled swim bladder in order to stay buoyant in the water. When fish are quickly brought to the surface from deeper water, this swim bladder can rupture, forcing gas through their bodies and in some cases forcing their internal organs out through their mouths (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020). These injuries commonly occur when fish are caught at depths of 25m or more (Veldhuizen et al., 2018). This risk may be reduced by bringing fishing gear to surface more slowly (interview proceedings), though this would have to be weighed against the increased time fish would spend suffering in the net or on the hook. Fish capture depth can also be reduced in some cases, which would improve welfare, but is normally constrained by the depth range of the species (Veldhuizen et al., 2018).


Fishes are poikilotherms, which means that their ambient body temperature varies according to their environment. This makes them susceptible to temperature changes, potentially resulting in death when the temperature is changed too rapidly. During fishing, fish are often rapidly drawn up from the deep, potentially passing through many temperature zones, and will finally be brought out of water, which represents a new temperature zone. This can cause significant shock to fish, which has been found to increase mortality (Veldhuizen et al., 2018; Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020).


Fish are not adapted to life out of the water, and so suffer a host of welfare problems in addition to asphyxiation when brought to the surface. These include the fact that their bodies are not designed to bear their weight in air. Fish may therefore be crushed under their own weight when not supported by more buoyant water (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020).


Especially for deep water fish who are not adapted to UV light, exposure to sunlight can cause serious damage to their eyes and skin in a short amount of time (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020).


Many methods of capture, especially seine nets, involve extreme crowding of fish. This can cause a great deal of stress to fish, and result in injuries as fish collide with one another or smash into each other as they flail (Waley et al., 2021).


Predation on the trapped fish is another common source of mortality. Trapped fish are helpless to escape or resist and so may be easy prey for a variety of predators like other fish and seabirds. Seabirds have learned that fishing vessels are an easy source of prey and will follow them in order to feed on caught and discarded fish (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020).


Finally, the most serious and all but ubiquitous welfare issue that fish face in the process of capture and handling is physical injury from the capture devices. Nets can flay their scales, lacerate their flesh, and choke or suffocate them as they become entangled and struggle to escape (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020). Hooks can severely damage the bodies of the fish, and many other types of injuries can occur during capture (Mood, 2010).


Trawling and dredging

During trawling, fish are chased by a funnel shaped net until they suffer exhaustion and are captured. The net is pulled behind the fishing vessel. As mentioned, exhaustion is particularly hazardous for fish. Once caught in the net they are crushed against other fish at the back of the net. This can last for several hours until they are drawn up to the surface.


The two types of trawling are midwater trawling (pelagic) and bottom trawling (demersal). A variation of bottom trawling called beam trawling uses a wooden or steel beam to keep the net open (Waley et al., 2021).


Dredging involves raking a framed net over the ocean’s floor, typically in order to catch shellfish (Waley et al., 2021). The net usually contains spikes to draw shellfish out of their habitats (Billington and Kirsch, 2021). Unsurprisingly, dredging is particularly likely to result in a large amount of bycatch, as well as destruction of habitat for many species of fish (Mood, 2010). Shrimp dredging is particularly damaging and is thought to account for between 55% and 27% of total bycatch across all fisheries, despite being a relatively small sector of the industry (Mood, 2010). Dredging and demersal trawling are likely to cause injury to fishes through rapid pressure changes as fish are drawn up rapidly from the deep (Billington and Kirsch, 2021).


Trawling, along with seine nets, has a higher mortality rate for captured fish than other forms of fishing (Billington and Kirsch, 2021). One study found a mortality rate of 29% for a 2 hour trawl or 61% for a 4 hour trawl (Mood, 2010). Chance of survival may be low even for fish who escape the nets; one study found mortality rates of 77% to 100% for even the herring who managed to escape (Mood, 2010).


Because of the large amount of bycatch and the leverage from the environmental impact of dredging and trawling, they may be a promising target for full ban or for further restrictions (Waley et al., 2021).


Hook and line

Compared to methods involving nets, in hook and line fishing, there is less bycatch and fish are typically brought aboard sooner with lower mortality rates (Mood, 2010; British Sea Fishing, 2012a).


Having said this, one practice may jeopardise this potential for higher welfare. This is the common practice of ‘live baiting’ which consists of impaling small fish on a hook while still alive to be eaten by the target fish (Mood, 2010). Alternatively, in a practice called ‘chumming’, these fish may be scattered among predatory fish such as tuna to induce a ‘feeding frenzy’ and make the predatory fish easier to catch. They may be confined for days or months in low welfare conditions with high mortality leading up to this use (Fishcount, no date a). Assuming that one live fish is used per fish caught, the practice may result in a colossal amount of suffering. The use of artificial lures would result in a huge welfare improvement (Mood, 2010).


Hooks of course can deeply damage the mouths, throats or any other parts of fish from which they are hooked. Injuries can be especially severe if fish are hooked in an area other than their jaw. One study found that 23% of salmon hooked by trolling vessels were hooked through the eye (Gregory and Grandin, 1998). Gill hookings were also common and particularly lethal, with 30% of salmon hooked by the gills dying soon after hooking and another 55% dying four to six days after they escaped. In fish physiology, oxygenated blood flowing from the heart must pass to the gills on its way to the brain. A hook in the gills can disrupt this and block oxygen from reaching the brain resulting in death (Gregory and Grandin, 1998). The use of J style rather than circle style hooks has been associated with reduced risk of fishing being hooked on areas other than the jaw. Fish may also become extremely exhausted and distressed as they struggle to free themselves from the hook (Mood, 2010).


One method of hook and line fishing is longline fishing; one type of hook and line that uses a particularly long line with many hooks (Mood, 2010). Typically, many lines are thrown off each vessel. In this method, the fish are hooked and brought up to the surface less frequently. It can take many hours for this to happen in some cases (Mood, 2010). Trolling is another form of hook and line fishing that consists of trailing a number of fishing lines with baited hooks off the back of a slowly moving vessel (Mood, 2010).


For fish who are too large to bring aboard with a fishing line, a special hook on a pole called a gaff is used. The hook end is stabbed into the fish in order to lift or heave them into the boat. This seriously injures the fish from the initial wound and from the hook being dug around in the flesh of the fish to gain leverage. Fishers have also been observed using gaffs as summary execution devices by stabbing the fish multiple times and then leaving them to bleed out (Billington and Kirsch, 2021).


Hanging nets

Hanging nets are nets that are left hanging in open water for fish to swim into and become entangled. They are not visible to fish. They are also called tangle nets, drift nets, or gill nets (British Sea Fishing, 2012a). They may be left for many hours or even days, greatly increasing the amount of time that fish are left to struggle and suffer (Mood, 2010). Fish are often cut by the nets during their struggling and may become unable to breathe as they are caught by the gills or entangled. Fish in hanging nets are particularly vulnerable to predation during this time (Mood, 2010). The process of removing fish from the hanging nets is also particularly rough and liable to inflict further injury (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020).


Because they are left without oversight for such long periods, many bycatch animals are already be dead when found or are likely to die shortly after release (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020). Hanging nets are sometimes discarded in the ocean after use and can continue to catch animals, causing senseless suffering to many (Mood, 2010).


Welfare may be improved by pulling up nets more often (under 1 hour soak time), using less damaging netting materials, and in some cases by avoiding fishing in warmer weather (Mood, 2010). The use of smaller nets may also be helpful in reducing the amount of bycatch.


Seine nets (purse seine)

The seine nets are very large nets which are sometimes being pulled and operated between two vessels. They can be as long as 2,000 metres and reach depths of up to 200 metres (Billington and Kirsch, 2021). During purse seine netting, fish are slowly surrounded by the nets until they form a circle that the fish cannot escape from. After this, the nets and trapped fish are drawn up on board (Mood, 2010).


As the nets are drawn up, the crowding of the trapped fishes increases dramatically, causing a great deal of stress and resulting in many injuries to fish through collisions with other fish (Mood, 2010). The process is typically faster than trawling, with one study finding it to last 90-160 minutes (Mood, 2010). However, this is still a very long time to suffer a high level of injury and stress. Along with trawling, seine nets have higher mortality rates than other forms of fishing (Billington and Kirsch, 2021). Welfare can be improved by reducing catch sizes to limit crowding, crowding ships in steps, and by using pumps instead of hauling to get ships on board (Waley et al., 2021).


Seine nets are generally non-selective fishing gear, and they pose a particular danger to dolphins (Mood, 2010). However, some things can be done to make them more selective, such as using methods of attracting the target species, like floating lights for sardines and anchovies (Mood, 2010). The net can also be evaluated prior to pulling it up, and if the bycatch rate is found to be too high, the net’s contents can be released. However, the mortality rate for released animals may still be high in this case (Marçalo et al., 2019). There are methods of evaluating bycatch automatically by using hydro-acoustics that are currently under development in Norway (Mood, 2010).


Traps

The use of traps is a common way to catch crabs and lobsters, and occasionally fish. They are lured into the traps by bait, and once inside they are unable to exit. Bait fish are also occasionally used in traps, which of course inflicts horrible suffering on the baitfish, but overall traps have welfare benefits over other approaches. (Mood, 2010).


Traps are relatively selective, and so do not generate much bycatch (British Sea Fishing, 2012a). The survival rate of trapped and released bycatch is also relatively high (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020). Traps are also less likely to injure animals, though injuries may occur while attempting escape, and being trapped is still distressing to the animal (Mood, 2010). The enclosure of traps may also protect the animal from some forms of predation that would be susceptible with other fishing methods, though some predators such as moray eels may still be able to attack them (Mood, 2010). The point of retrieval from the trap probably represents the greatest source of stress and injury to fish (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020).


Handling

After capture, fish are handled whilst they are brought on board, removed from the gear, sorted on board, and slaughtered. This is a very stressful experience for fish and it can also lead to severe physical injuries, especially when they are roughly handled, such as being thrown around (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020). A particularly damaging case of this is the use of a gaff, which, as mentioned earlier, has horrible animal welfare consequences. Handling can be reduced with the use of pumps to bring fish on board, which typically represents welfare improvement (Mood, 2010).


Particular attention should be paid to minimising time out of water for fish as this poses a particular risk of injury for them. Most fish are still alive and conscious after being brought on deck, and many suffer a lingering death even if they are slaughtered rather than simply left to die (Mood, 2010).


Death

No method of killing an animal is completely without risk of suffering. However, some methods may involve less suffering. These ‘more humane’ methods either involve 1) pre-slaughter stunning to render the animal more or less insensible to pain or 2) provide a nearly instantaneous or non-aversive death.


Fish are extremely tough animals, which complicates the process of quickly slaughtering them. For example, decapitation or cervical dislocation may result in an instant death for some species, but for others even this is not instant (Diggles, 2016). This means that fish tend to take a much longer time to die than land animals. Because of this, stunning before slaughter is particularly important for fish. It is therefore particularly unfortunate that it is almost never provided for wild caught fish.


Death is inevitable after capture, and quick clean death may unfortunately be the best that fish can hope for at that point. Unfortunately, far from any of these methods, most fish that survive the capture process are not properly slaughtered. Instead, alongside their capture and handling injuries, they are left to die from asphyxiation, live gutting, chilling in an ice slurry, or a combination of these methods (Mood, 2010). Of these, asphyxiation is the most common cause of death for fish caught in UK waters (Billington and Kirsch, 2021).


One study (Van de Vis and Kestin, 1996) found that the time it took the various fish species studied to die was 25 - 65 minutes with gutting and asphyxiation or 55 - 250 minutes without gutting. This is a shockingly long time for a death to take place. In this study death was operationalized as the state in which brainstem responses such as breathing no longer took place. They noted that 15% of eels were able to swim away in a coordinated manner after gutting and chilling.


Because this is just one study, its result should be treated with caution. Saulius (2020) raises some uncertainty surrounding the study, discussing some other sources on this question, though most are less authoritative than this study. Ultimately, more research is needed on this question.


Fish are often placed into an ice slurry before or after slaughter. This is primarily done to maximise meat quality, but it is also sometimes believed to increase welfare by putting the fish in a dormant state where they are less sentient (Waley et al., 2021). It is true that fish outwardly display fewer signs of low welfare in response to chilling, but this is because they enter a state of suspended activity, and there is evidence that they do find the experience highly stressful (Mood, 2010). However, Diggles et al. (2016) disagrees and argues that chilling improves welfare in many cases.


Because it reduces their bodily functions, including the need for oxygen, chilling may also extend – rather than shorten – their time spent suffering and dying (Mood, 2010). Some argue that carefully controlled chilling might work in the case of crustaceans, but stunning is a better evidenced method (Conte et al., 2021). Chilling may be mistaken as a relatively humane method because it causes crustaceans to become inactive, but this is not the same as being insensible to pain (Mood, 2010).


The total amount of suffering for fish may be thought of as duration multiplied by intensity. Since fish will be slaughtered painfully in any case, injuries prior to slaughter that hasten their death may be a slightly lower priority to work on. This is because, if injuries quicken death for the fish, they will reduce the duration of suffering, even if they also increase intensity. To some extent, it would be a case of one painful manner of death replacing another, and this tradeoff could possibly in some cases be net beneficial for the fish.


One consideration that counteracts this is that fish whose bodies are too damaged by injuries may be discarded, because it will be too hard to sell the meat, meaning that other animals will have to suffer and die in order to meet the demand (Zeller et al., 2018). This argument against the importance of protecting fish from injuries during capture may also cease to be true at some point in the future if stunning before slaughter becomes widely practised on fishing vessels. Once this happens, their death during slaughter may be less painful than death from accrued injuries during capture.


One thing is clear: it is imperative that fish be slaughtered much more quickly than is currently practised. Even if stunning cannot be provided, more lethal methods of killing should be used so that death should come more quickly.


Having said this, many welfare improvements will not substantially affect the total number of fish killed, their welfare will just be improved during slaughter. This consideration therefore does not apply in those cases; it only applies in cases such as banning trawling that stand to change the total number of fish killed.


‘Humane slaughter’

Humane slaughter of wild caught fish is rarely practised. However, some methods have been established, many of them pioneered in the aquaculture industry.


Humane slaughter may be automated by using certain devices. The two methods of this are percussive and electrical stunning. Both are largely recent developments and still only practised on a limited scale.


Manual methods also exist and are practised more widely, though the practice is mainly done for large, high-value fish and is still relatively rare. These are practised with a sharp spike through the brain or a blow to the head (Mood, 2010). A variation of spiking called ‘Ikijime’ also uses a pithing rod extended along the spinal column in order to minimise muscle contraction. This is done because humane slaughter improves meat quality, and tuna is a very high cost product. However, this could be more widely practised on medium-size fish as well (Waley et al., 2021).


A downside of this method is that it requires training in order to precisely hit the small brain of the fish. Even with training this precision is difficult on the unsteady surface of the boat and with a struggling fish. Any errors will result in a great deal of suffering for the fish (Waley et al., 2021). Automated versions of this method are also problematic. Robb et al. (2000) found that 50% of the strikes of an automated spiking machine were inaccurate.


There are further difficulties in adapting existing methods of stunning fish in aquaculture to the wild caught context. The extremely large catch sizes and the many different species caught by many fishing industries presents a further barrier to stunning before slaughter (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020). The rocking decks and the general chaos involved in fishing presents a significant challenge to adapting these technologies to the wild caught context.


Two methods of electrical stunning can be distinguished: within water stunning and dry stunning, with the latter being significantly more stressful for fish (Mood and Brooke, 2019). It is very important that electrical stunning is implemented correctly. When done incorrectly, it may only result in paralysis – not true stunning. This will not only fail to protect the fish from the agony of slaughter, but can in itself be extremely painful (Van de Vis et al., 2003). In order for it to be done correctly, the right frequency must be used for the species in question. This must be exacted through lab studies of the subject. Data on this is available for many of the species fished in UK waters, but there is much more to be learned. Unfortunately, there are reasons to think that it is often not done correctly, leaving fish paralyzed yet fully conscious (Aquatic Life Institute, 2021).


Adding a food grade anaesthetic to the water may also be an option, alongside other methods, for making their death slightly more humane. Isoeugenol is a medication that could be used for this purpose. This would likely not render the fish completely insensible to pain, but there is evidence that it reduces at least visible signs of pain and distress (Mood, 2010).


To be effective, humane slaughter needs to be carefully tailored to the species in question. Fortunately, specific recommendations for humane slaughter already exist for the main species in UK fisheries (Billington and Kirsch, 2021)


Humane slaughter prototypes

We now turn to successful implementations of the above. All of these humane slaughter methods are only practised on a limited scale, but can serve as prototypes for future more comprehensive implementations.


This video shows an automated percussive stunning machine being used by the Alaskan company Wild Salmon Direct. The fish are passed through a machine that gives them a blow to the head to stun them without removing them from the water. The process looks quite straightforward, though automated percussive stunning is not always accurate, especially on a moving vessel. (Fishcount, no date c).


These methods only work effectively with a smaller number of larger fish. For fisheries that have large numbers of small fishes, other methods must be found. Additionally, adapting these methods for salt water is difficult because of its greater conductivity (Mood, 2010).


Crustastun is a UK developed stunning method for crustaceans, and evidence suggests it does not cause stress in the animals (Conte et al., 2021). It has models for individual (such as restaurant) use and for shellfish processing plants, but no on board models. The shellfish processing plant models cost over £60,000 (McSmith, 2009). Another method of electrically stunning crustaceans, “StunCrab”, also appears to be effective in stunning the animals (Conte et al., 2021).


One electric stunning prototype is the Dutch trawling company, Ekofish. Ekofish has two vessels that catch turbot, brill and other fish in the North Sea. They use a STANSUS stunning machine that is the result of a collaboration between Dutch and Norwegian scientists. In this prototype, captured fish are moved along a conveyor belt through an electric dry stunning machine. Their first vessel uses dry stunning, but the second vessel improves welfare by keeping the fish and water during this process. After stunning, the fish are handgutted and chilled (Mood, 2010).


Humane Harvest is another humane slaughter method from the Alaskan cod fishing company, Blue North, owned by the Bristol Bay Native Corporation. They currently have one very large long liner vessel that implements the technology. The lines are drawn up through a “moon pool” which takes the fish up individually through an entrance port at the bottom of the vessel. Fish of the wrong species can be recognized and released before being drawn up, significantly reducing bycatch. This also eliminates the need to gaff the fish to bring them on board. They are then taken to an automatic semi-dry stunning table and immediately slaughtered.


Blue North claims that stunning before slaughter greatly increases the quality of the fish meat, both in taste and health. Additionally, they claim there is a benefit to workers’ health because they do not risk injury by exposure to panicked, struggling fish. These benefits to humane harvesting may provide an avenue for change. The average fish caught by this company is between 10 and 20 pounds and the meat is sold as a premium product. Even if many others in the industry do care enough about fish welfare to implement reforms on their own, they may be much more responsive to these other social goods and to the premium this may enable them to charge. It might be hard to replicate this in fisheries with smaller, less expensive fish, though it could be replicated in the UK due to the substantial cod fishing industry in UK waters (ALI, 2021; Waley et al., 2021).

Another stunning method has been pioneered by Efectos Navales del Atlántico. This device has fish come into contact with an electrode in the water as they approach the boat, which stuns them before they are taken up and slaughtered (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020).


Bycatch

Most methods of commercial fishing are highly nonselective, and so catch large numbers of non-target species. This is called bycatch. These accidentally caught animals typically have no commercial value to the fishermen and so their suffering and deaths from fishing operations represent a complete waste, with their meat not even replacing the meat of other animals by satisfying demand for the product. There are some exceptions to this. For example, the selling of bycatch tuna is permissible in the UK and since tuna is a highly lucrative product, this is an attractive option for fishers (Harper, 2021).


Bycatch rates vary dramatically according to fishing methods, and accurate data is missing in many cases, but overall the EU estimates that 40 to 60% of EU North Sea catches are bycatch, or one fifth of catches worldwide (Cook, 2003; Mood, 2010).


Bycatch animals are typically left to asphyxiate on deck or are thrown back into the ocean. Overall survival rates are extremely low for fish, with only 1-2% surviving according to one study (Cook, 2003). This low survival rate may be the result of physical injuries or simply stress (Billington and Kirsch, 2021). Because of the low survival rates, it is important to minimise the number of bycatch animals, rather than rely on returning caught animals to the ocean.


The number of porpoises caught as bycatch in the UK in 2017 has been estimated at 1098 (Calderan and Leaper, 2019). Estimates of the pressure this puts on different populations of cetaceans typically find excess mortality caused by this to be in excess of 2%, which may be unsustainable for maintaining populations of the slow breeding animals (Cook, 2003). This provides another angle for focusing on reducing bycatch that will be more persuasive to people who do not care about fish. Many other marine animals are also at risk of bycatch including sea turtles, seals, and many species of seabirds (Cook, 2003).


Even when fish are thrown back, the ship may have already moved a significant distance and the animals may be displaced from their home environment and community. Many animals are only able to survive in a relatively narrow range of environmental parameters, such as depth, temperature, currents, and biome. This could mean that they are unable to survive long term, even if they survive their injuries (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020).


Reducing Bycatch

The best method for reducing bycatch is to use fishing methods and techniques that naturally result in lower rates of bycatch. Nevertheless, there are some methods that have been devised to reduce the amount of bycatch (Cook, 2003).


Bycatch can be reduced by altering the properties of the net to make it more selective. For example, a net could be made with holes just large enough to snare the target organism while letting many smaller fish pass through (Cook, 2003). This practice has indeed been found to reduce bycatch, though in one study it was found to increase the risk of injury to the fish that were caught, making it unclear whether this modification is desirable overall (Mood, 2010).


Another strategy is to make special, larger holes scattered throughout the net that non-target species can escape through called bycatch reduction devices (Mood, 2010). However, even if these are successful in allowing non-target species to escape, the animals may still be injured and severely stressed during the process and there may still be a significant risk of mortality (Davis, 2002). Fish that survive are often weakened by the process and may later succumb to predation or disease (Chopin and Arimoto, 1995).


Estimates of mortality rates vary widely according to species, type of fishery, and study design (Chopin and Arimoto, 1995). For example, Chopin and Arimoto (Chopin and Arimoto, 1995) found mortality rates for escaping animals between 0% and 100% for cod (one of the most commonly caught UK species). Suuronen et al. (Suuronen, Erickson and Orrensalo, 1996) found mortality rates between 75% and 90% for herring (another commonly caught UK species). The data of these studies is often limited to the short term because of the difficulty of assessing the influence on long-term mortality rates, and they may therefore underestimate overall mortality (Chopin and Arimoto, 1995).


There are a number of devices that can be added to nets to reduce bycatch. As a unique solution that might help prevent bycatch of sharks, fishers can attach a magnetic metal layer to hooks or nets that only they can distinguish because of their electromagnetic sense (Billington and Kirsch, 2021). Similarly for cetaceans, acoustic pingers may be added to nets to alert the animals to their presence. These devices periodically admit a noise that can be picked up by the sensitive hearing of cetaceans, though they also attract seals and therefore their impact overall is unclear (Mood, 2010; Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020). Adding lights to nets can also reduce bycatch of whales, turtles, and seabirds (University of Exeter, 2019). Finally, a type of panel can be added to the bottom of nets to reduce bycatch of crustaceans and other invertebrates, as well as reducing predation from these animals on trapped fish (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020).


TRACTABILITY


Public Opinion

Fish welfare in wild caught fisheries has long been a neglected topic, even for animal advocates. However, the 2021 Netflix documentary, Seaspiracy, was an immensely popular portrayal of the issue, reaching the top 10 most viewed movies on the platform in several countries in the week that it was released (Korban, 2021).


Though specific information on attitudes towards the welfare of wild caught fish is lacking, surveys generally suggest that the UK public wants more action on fish welfare. In general, the polling data on the public’s concern for fish and perception of their mental abilities (including the ability to feel pain) is somewhat less than for other animals, but not dramatically so (Šimčikas, 2020).


The most relevant data point we found for the purposes of this report was that 76% of the UK public believes that fish should be protected to the same extent as other animals used for food (CIWF, 2018). This implies that they would be in favour of much stronger protections for wild caught fish, though people are unlikely to have thought through the full implications of their answers to survey questions and this should not be taken at face value.


Another relevant data point is that 89% of people across Europe believe that humane slaughter is essential for good welfare, 79% of people believe that fish welfare should be better protected than it is now, and 73% of them also believe that fish feel pain (Waley et al., 2021). Similarly, only 28% of the public surveyed in the UK agreed that the aquaculture can be relied upon to ensure fish welfare without a legal requirement (Daw, 2021). It is unclear if they would have a more or less optimistic view of the fishing industry.


These are all encouraging signs, but we are sceptical that people would act according to the stated opinions about protecting fish. We suspect that in practice they are far less willing to protect fish. Fish welfare has been a much more neglected issue than the welfare of other animals, which suggests it is a cause that people effectively care less about (FWI, 2019).


Having said this, asks that also affect recreational fishing would likely face opposition from the 3 million recreational fishers in the UK (Winfield, 2016). This is a much larger population than the approximately 11,000 professional fishers in the UK. It might be thought that, despite its smaller size, the professional lobby of the fishing industry may be better funded, though it is not clear if this is true. A survey of freshwater anglers revealed that the economic contribution of their spending is an estimated £1.46 billion, and this spending is thought to support 27,000 jobs, compared to less than half of the revenue and jobs of the fishing industry in the same year (Environment Agency, 2018; Marine Management Organisation, 2021). Alongside the smaller number of animals affected by recreational fishing, this potentially larger lobbying potential suggests that, when possible, we should target inventions against commercial fishing rather than recreational fishing for less resistance.


Finally, the public has a generally rosy perception of the practice of fishing. Schlag and Ystgaard (Katrin Schlag and Ystgaard, 2013) found that fishing is generally mythologized by the European public they surveyed, being seen as more natural, traditional, and wholesome than aquaculture. This wSystemsill make wild caught fish advocacy efforts more difficult and will have to be tackled by organisations working on this subject.


Support from Members of Parliament

The UK government's recent recognition of the sentience of animals also extends to wild caught fish, which may provide a way of arguing for more concrete protections for them that was not available previously (Garrett and McCulloch, 2022).


The Conservative Animal Welfare Foundation released a report on Fish Welfare (Billington and Kirsch, 2021), which calls for many important fish welfare improvements in aquaculture and wild caught fisheries. They have considerable support in parliament – they list seven current MPs as patrons of their organisation (CAWF, 2020).


Unfortunately, the fishing industry already feels politically marginalised, and politicians have demonstrated a willingness to take industry concerns very seriously. Many in the government would not wish to further alienate members of the industry (interview proceedings). One example of this is that fisheries have been a prominent topic in Brexit negotiations, despite only making up 0.03% of the GDP of the UK (Parker, 2020; Ares et al., 2021). This could make strong changes difficult, without work to make changes more palatable to the industry. Having said this, almost all animal advocacy efforts face significant opposition from animal industries.


Another option would be to focus specifically on Scotland and its devolved Parliament. This is promising because Scotland is responsible for a significant portion of UK fishing. Its fleet is also top-heavy, comprising an easy majority of UK vessels over 10m, and it may be particularly promising to work on larger vessels because they may be able to implement more significant reforms, as well is easier to communicate with than a much larger number of vessels (such as humane slaughter at some point) (Marine Management Organisation, 2021). Scotland’s population is also less than 10% of England’s (Park, 2021), which arguably means that its policies are easier to influence through campaigns and lobbying because the budget is smaller and each vote represents a greater share of the total.


It may be especially promising to focus on Scotland because of the position of the Scottish Green party. The seven elected MPs of the Scottish Green Party are in a ruling coalition with the 64 elected MPs of the Scottish National Party (Editors, no date). This means that the Scottish Greens have unprecedented power.


The Scottish greens have pledged to:


  • Introduce controls on the type of fishing gear and harvesting levels allowed, including restricting the area where dredging and seabed trawling is permitted.

  • Redress the historical consolidation of quotas in the hands of a few by redistributing them, so that the wealth generated from the industry is more equally shared and small businesses are the key beneficiaries.

  • Make all public support to fisheries businesses, including licences and quotas, conditional on operating in an environmentally and socially responsible way.

  • Invest in better enforcement, including more compliance vessels and the introduction of mandatory on-board cameras and remote electronic tracking and monitoring systems on all commercial vessels.

  • Introduce a Scottish Fisheries Bill to establish a new system of fisheries support that is based on observing mandatory catch limits and incentivises environmentally and socially responsible operations.

  • Exclude dredging and trawling from much of our inshore waters, with specific areas identified in line with local ecology, but with the default being within 3 miles of Scotland’s shore.


While these do not mention fish welfare, they may well promote fish welfare and they are encouraging signs from Edinburgh. The compromise platform put forward by the coalition has also recently been released:


The agreement promises to protect 10 percent of Scotland’s seas from trawling and dredging by 2026 and to cap fishing at current levels within three nautical miles of the coast. ‘We are determined to make a step change in marine protection,’ it says.


They’ve also expressed concern for the welfare of fish on other occasions in the context of aquaculture: “[T]he Greens want to phase out open net pen salmon farming and block the growth of the sector until environmental and animal welfare concerns are discussed.”


Policy Window

The UK has recently left the EU with its shared legislation and fishing area. This means that the UK is in the process of drafting legislation to replace the EU legislation used to apply to the UK. The UK has also been passing new legislation that exceeds EU legislation in animal welfare standards in many cases. This makes it an excellent time to be focusing on animal welfare in the UK.


Enforcement

Undercover investigations suggest that enforcement (especially government enforcement) of fish welfare in Scottish aquaculture is very weak (CIWF and OneKind, 2021). This does not bode well for (at this point theoretical) welfare enforcement in wild caught fishing, because welfare inspection at sea presents additional challenges.


However, though welfare is not currently monitored on fishing vessels, they are currently inspected for permitted species to make sure they do not exceed quotas and for other environmental reasons. This includes physical monitoring by dockside inspections, surveillance aircraft, and patrol boats (including occasional boardings) (Course, 2015). It also includes electronic monitoring for vessels over 12m (I-VMS) that share the location, speed, and heading of vessels (DEFRA, no date). Vessels under 12m in England will be required to have these systems by the end of 2022 (Marine Management Organization, no date). This monitoring largely exists for environmental reasons, rather than welfare reasons. However, some environmental reasons are also welfare reasons, such as reducing bycatch, but in many cases these concerns will differ. Though these methods of surveillance do not currently monitor welfare, it may be possible to enlist them for welfare enforcement, once welfare becomes enforceable.


In addition to these methods, requiring mandatory CCTVs on fishing vessels is another way of increasing enforcement. This policy is taken seriously in the UK and the EU, and may well take place without the work of animal advocacy organisations. If so, animal welfare could be one of the aspects that we monitor them for. The House of Lords placed an amendment in the fisheries bill that would have required CCTV on fishing vessels (Remote Electronic Monitoring: Instrument of Control or Assurance Tool?, 2020).


CCTVs are required in slaughterhouses in England, Wales, and Scotland, and are widely used (but not mandatory) in Northern Ireland (DEFRA, 2018; The Newsroom, 2018; Jones, 2021). Since similar arguments apply for CCTV monitoring on fishing boats, it could be promising to build on this precedent and push for requiring them.


The WWF (Course, 2015) conducted a feasibility study on implementing CCTVs on fishing vessels in the UK. They estimate that installing the equipment and monitoring 10% of the data would cost £4697 per vessel. Moreover, they estimate that it would cost around the same as is currently spent on monitoring efforts, but current efforts monitor only 0.1% of the hours of fishing vessel operation.


Mandatory CCTV use on fishing vessels therefore seems both relatively politically popular and economically feasible. It would therefore be synergistic with other asks to improve wild caught fish welfare. If it is successful and once other welfare measures for wild caught fish are passed, CCTVs may enhance enforcement of fish welfare.


Legal Hurdles

Including wild caught fish in the Animal Welfare Act would involve amending primary legislation, which may be difficult. It seems significantly more difficult than, for example, writing a new piece of secondary legislation such as a code of practice. We are not aware of precedents for adding animals to the Animal Welfare Act, though Crustacean Compassion is currently working on this (Crustacean Compassion, no date).


Campaign angles

In addition to a strong focus on welfare, a campaign that successfully leverages other angles would seem to have a much stronger chance of success. Appealing to a diverse range of issues will help bring a broader range of people on side and reduce opposition.


There are also a number of campaign angles that could get greater support through the greater public enthusiasm for environmental issues.


  1. Dolphin and porpoise bycatch have received a great deal of popular concern. These animals could therefore be the poster children for a campaign to reduce bycatch. However, the interests of dolphins are not always aligned with the interests of other animals. For example, using floating objects in purse seine fishing will attract fish but not dolphins and therefore lower the relative proportion of dolphins caught. However, other potential bycatch animals are attracted to the floating objects and so the strategy may raise the total proportion of bycatch (Mood, 2010).

  2. Reducing ‘ghost nets’ – abandoned nets that continue to catch animals and contribute significantly to the amount of garbage in the world’s oceans – is another possible environmental campaign angle with a significant animal welfare benefit as well (AAA, no date a).

  3. Targeting larger fish rather than smaller fish (whether of the same species or different species) will also have important welfare benefits while potentially having environmental benefits (increasing fish population sizes) that could support a campaign.

  4. Dredging, beam trawling and demersal trawling rip up ocean floor habitats, so there is a strong environmental case for preventing them. There may also be a significant animal welfare reason for doing so because of the large amount of bycatch that they generate (Billington and Kirsch, 2021). Fishing fleets account for 1.2% of global oil consumption, though this is a lower total than other forms of animal agriculture (Mood, 2010).


In addition to environmental arguments, there are some human health arguments in favour of improving welfare and wild caught fisheries. Acute stress immediately prior to slaughter has been found to reduce meat quality in a variety of species (Mike Breen, Neil Anders, Odd-Børre Humborstad, Jonatan Nilsson, Maria Tenningen, and Aud Vold, 2020). This is why the meat of large, expensive fish is sometimes slaughtered in a more humane way, such as through spiking. This provides some economic incentive to adopt more humane slaughter practices, and is another angle from which to argue for these reforms.


Additionally, higher welfare practices may help to protect the health of the fishing crew. The process of handling fish to bring the board can be hazardous to the people handling the fish since the fish may struggle very forcefully. There is also the risk of repetitive strain injuries from the repetitive motions involved (ALI, 2021). This can be minimised with the use of pumps to bring the fish on board. Similarly, stunning before slaughter can reduce risk of injury to fishers from flapping and writhing fish (interview proceedings).


EXPERT INTERVIEWS


The initial ask that we considered with this report was removing the exception for animals affected by fishing activities from the Animal Welfare Act. However, our expert interviews convinced us that this would likely be too large of an ask and so likely to be politically infeasible. Though it is not entirely clear what would happen if the exception were removed, a very plausible interpretation of this would be that fisheries or even anglers could face prosecution. The industry would face massive disruption and might even end overnight. As with the response of politicians in 2004 to the original Animal Welfare Act not including a fishing exception that may have resulted in the prosecution of anglers, politicians who interpret removing the exception in this way would be very unlikely to allow it to be removed (BBC, 2004). In response to this, we pivoted the report away from this topic, towards more achievable asks.


Many of our experts also emphasised the need to work with fishers and the fishing industry. They proposed a need to identify barriers in place of broader adoption of higher welfare practices and cooperate with the fishing industry in order to solve those. To illustrate this, they brought up the chaos in the aftermath of the Landing Obligation to illustrate this point. They argued that the fishing industry was unable to satisfy this requirement, and that this led to resentment.


One proposal they had for working with the industry was the certification schemes that would allow forward thinking members of the industry to be rewarded for their efforts and stimulate the adoption of technologies and practices that could eventually permeate to the broader industry. They also mentioned that greater government funding for research could be a way of working more cooperatively with the industry.


They mentioned various other benefits of higher welfare fishing, such as protecting the health of fishers, a better tasting product, and a more nutritious product. They stressed that these benefits will also be important in shifting the industry in a more positive direction.


They also brought up a number of important details, such as the welfare benefits of pumps in reducing harmful handling. They mentioned that, though chilling was contraindicated in some species (such as herring) as causing much more suffering, it was relatively humane for other species (such as mackerel). Another point was that reducing time out of water would usually be less costly for fishermen, so would be a more promising ask and would reduce fishing times. Additionally, electrical stunning was likely to be best, and that stunning machines would be practical enough for larger vessels, but that for smaller vessels manual percussive stunning may need to be used.


They did not think there would be much risk of substitution between wild caught fish and aquaculture fish if the price of the former were raised by welfare reforms. This is because they think that the two are already different products, with wild fish already a premium product.


COUNTERFACTUAL REPLACEABILITY


In general, there is much less attention and funding directed to the welfare of wild caught fish than there is towards fish in aquaculture, and far less again than is directed towards improving welfare in land animal agriculture. Having said this, there is some promising work going on in this space. However, this work is at an early stage, and has mostly taken the form of research rather than advocacy.


One exception to the general lack of advocacy on behalf of wild caught fish is the World Day to End Fishing (End of fishing, 2016). This was established by the advocacy group Pour l'Égalité Animale (PEA), and they help to facilitate protests in many cities each year on March 26 to push for an end to all fishing and aquaculture.


The Humane Slaughter Association is a UK nonprofit that recently awarded a prize of £166,000 to Nicola Randall, who is the Director of the Centre for Evidence-Based Agriculture at Harper Adams University for a global systematic review of humane slaughter methods for wild caught fish. The project began in July 2020, and the protocol for the project has now been published (James et al., 2022). The results of this will be used to inform a feasibility analysis on the most promising slaughter method for wild capture fish (HSA, 2020). This is a substantial amount of funding for an approach that sounds very promising.


There is also a very large research program into automatic on board stunning by SINTEF Fisheries and Aquaculture of Norway (Fishcount, no date d). This would include automatic electrical stunning followed automatically by automatic bleeding to help ensure death before a return to consciousness.


As mentioned in the “Support from members of Parliament” section, the Conservative Animal Welfare Foundation is interested in improving the welfare of wild caught fish (Advance Fish Welfare, 2021). They have some sympathy towards a ban on trawling (Billington and Kirsch, 2021).


The Aquatic Animal Alliance is concerned about this issue and has a set of recommendations for welfare improvements during world capture (AAA, no date a). They also recently published a welfare guide for wild capture fisheries (ALI, 2022). Finally, they created the Aquatic Animal Alliance, which is a coalition of 75 organisations that do advocacy work for aquatic animals, though this does not imply that all of these organisations are actively working on wild caught fish welfare (AAA, no date b).


Fishcount is a UK organisation that does research on the welfare of fish, including wild caught fish (Fishcount, no date b). They have written specifically about the prospects for humane fishing in the UK (Mood and Brooke, 2019), and their report, Worse Things Happen at Sea (Mood, 2010), is the most comprehensive work on the subject of the welfare of wild caught fish.


Eurogroup for Animals works on the welfare of wild caught fish within the EU, including publishing the report Catching Up: Fish Welfare in Wild Capture Fisheries (Eurogroup for Animals, no date a; Waley et al., 2021). Eurogroup for Animals is a coalition of 83 animal advocacy organisations throughout the EU, though again this does not imply that all of these organisations are working on wild caught fish (Eurogroup for Animals, no date b).


PRIORITISATION AMONG FISHING INTERVENTIONS


In the research for this intervention we identified a short list of interventions (subasks) that, at least initially, seemed promising in UK fishing. Evidence is rather weak for making detailed comparisons between these subasks, so we are not highly confident of our conclusions here. Instead, these are a preliminary set of possible subasks that further research might confirm or disconfirm.


In the longer term more ambitious asks could be pursued, but these are asks that we think are practical enough to campaign for now.


Preferentially catch larger fish; do not catch smaller fish

The principle behind this ask is simple: fewer individual fish must be killed for the same amount of meat if larger fish are killed. For instance, a 10g sandeel represents a minuscule amount of meat, compared to many kilograms of meat you might get from a larger fish (Mood, 2010). This can be done through selective fishing gear (for example with nets with larger holes so that smaller animals will not be trapped in them) (Fishcount, no date e). This may also incidentally reduce bycatch of other animals. This ask was mentioned by Fishcount, but we found no mention of this by other organisations (Fishcount, no date e).


In the UK, the most commonly caught species do not differ in size as dramatically as the above example. The largest of the comely caught species is cod, which typically weighs 8kg compared to 225g for herring (FishBase, no date; Mass.gov, no date). This represents a difference of 32 times in meat yield, but substitution across species is likely to be a much more difficult ask than substitution for larger fish within the same species.


There are already some regulations concerning this in the UK. Minimum allowable catch lengths are given for various species under UK legislation (British Sea Fishing, 2012b; Marine Management Organisation, 2017), and undersized fish are not allowed to be sold for human consumption, though they may still be sold for fish meal and fish oil. This may reduce the profitability of capturing smaller fish, and incentivize against the practice (UK Government, no date). In some cases, such as for herring and blue whiting, the size limits are close to the average catch size, so it might be difficult to push these. Nevertheless, even a small increase here would be impactful because of the huge numbers of these fish caught by the UK. For some other fish frequently caught in UK waters, there is more room to increase the minimum allowable size. These include cod, haddock, and possibly mackerel (Angling Trust, 2020). Many species also do not have a minimum allowable catch size (though all of the most commonly fished species in the UK have minimum catch sizes), and some limit could be argued for in these cases (Angling Trust, 2020).


These minimum allowable catch sizes are in place to allow fish to grow large enough to reproduce as well as to avoid wastefully catching small fish that will not yield much meat. Because this ask may lead to an increase in fish populations relative to a strategy targeting smaller fish, considerations around this (described in the crucial considerations section) apply more strongly than they do to other asks in UK fisheries. It may also be less effective than it appears because fish may just be captured once they reach adulthood.


Because of these size restrictions already in place, the most straightforward ask would be to increase the minimum allowable size for various species. However, the real question is whether this would work given that small fish may still be sold for fish meal and fish oil. There are also potential issues with compliance. For example, UK cod fisheries reported zero catches of undersized fish in 2018, too few to be believed. The true number of undersized fish they caught and illegally disposed of is estimated at 7,500 tonnes (Gordon, 2019). Finally (and most decisively) one of our staff members has found, through their experience in governmental work on fisheries management, that the specific size limits are set by both scientific and political factors and are highly unlikely to be susceptible to external pressure from animal advocacy organisations (at least in Australia).


An article reviewing capture injuries, Veldhuizen et al. (2018), identified another benefit to this policy; that smaller size is associated with increased risk of mortality and injury during capture, so preferentially catching larger fish is also likely to reduce suffering for this reason as well. However, this pattern was not universal. For example, some studies of herring found higher mortality was associated with larger size.


The long-term effect of this policy on the average size of fish from captured species in the oceans is unclear. Overfishing has tended to decrease the average size of fish caught, working against this (Audzijonyte et al., 2013). On the other hand, selecting for the capture of large fish creates evolutionary pressure for fish to mature more slowly and perhaps never reach large sizes (Jørgensen, Ernande and Fiksen, 2009). Larger fish sizes in the wild is associated with decreased mortality because, for example, decreased risk of predation (Audzijonyte, Fulton and Kuparinen, 2015), so reducing the average size of fish may decrease welfare, though there are many complexities here.


Though size limits are already practised and there is a strong non-animal welfare rationale to help achieve this ask, the fact that external organisations are unlikely to be able to influence these size limits means that we do not recommend this ask.


Ban live baiting

Live baiting, the use of small live fish as bait on the end of hooks or thrown out of boats to cause feeding frenzies, is a particularly horrific fishing practice. Live bait fish are typically raised and transported in terrible conditions, and then impaled alive on a hook to be eaten alive by the targeted fish (Mood, 2010).


This practice is horrific, but the numbers of fish it harms are probably significantly lower than other practices we consider in this section. Active capture techniques, including long lining, make up a minority of capture methods used in the UK and bare hooks, artificial lures, or dead fish meat are more commonly used (Mood, 2010; Marine Management Organization, 2020). The use of dead fish is itself problematic, though it is preferable to the use of live fish.


One risk associated with banning live baiting is, if it makes long lining proportionally less profitable than other methods of fishing, it is possible that it would cause fishers to stop long lining in favour of other methods. Since long lining probably has higher welfare than most alternative practices, this could cause some increase in suffering, with a small chance that this would increase net suffering. Nevertheless, alternatives are already more common, suggesting that they are also more profitable, and Davie and Kopf (Davie and Kopf, 2006) write that “[l]ive-baiting is not essential to capture most predatory fish and is discouraged if fish welfare is to be considered”. Different forms of fishing may not be easy substitutes with each other since they are best at capturing differing species of fish. Overall, we judge that the risk of substitution with other forms of fishing is not large.


As mentioned, live baiting has already been banned in Scotland. This may mean that it is easier to implement this ask in the rest of the UK, because that important precedent has already been set. However, it also means that the ask is less impactful because Scotland already accounts for the majority of the fishing done in the UK .


There is also a potential environmental angle behind a campaign to ban live baiting; if the bait fish escape, they can become invasive to the area. However, this applies much more strongly to freshwater contexts than to saltwater.


Limit time out of water

Time out of water is a particularly painful time for fish. Fish are of course not designed for life outside of water, and suffer many harms from this, in addition to the obvious harm of asphyxiation. Since they will die eventually, it is better for this to come more quickly than it does under current practices, so that their suffering is not greatly prolonged. Compared to limiting time in the nets or on the line, limiting time out of water may also be relatively less costly for fishers to slaughter fish more quickly, making it an easier ask for the industry to adopt (interview proceedings). This ask would likely have to include specific proposals for allowable time periods out of water based on capture methods and species.


Unlike preferentially catching larger fish or banning trawling, this ask does not have any strong rationale other than animal welfare. This likely makes it more difficult to push through than the other asks.


Ban or restrict bottom trawling and dredging

As described, bottom trawling and dredging are capture methods that tend to result in particularly high numbers of bycatch, as well as being notorious for the environmental damage that they cause. Along with purse seines, these methods are associated with increased mortality more than other capture methods, which is one of the best proxies we have for the relative suffering associated with them (Veldhuizen et al., 2018). Fishing depth is also associated with increased mortality, perhaps because of barotrauma among other injuries, and bottom trawling and dredging is typically done at deeper depths than other forms of fishing (Veldhuizen et al., 2018). Having said this, data to inform comparisons of the amount of fish suffering associated with different methods are lacking, and so we cannot be very confident that they are associated with more suffering than alternatives. However, given the evidence of high rates of bycatch, increased mortality, and a judgement call based on how bad the capture method sounds, we believe that it is worse than the capture methods that would counterfactually replace it if it were banned. Bottom trawling is also a common method for catching shrimp, which is a type of fishing that both results in a disproportionate number of animals being killed and results in high rates of bycatch (though bycatch rates are lower than in tropical shrimp fisheries) (Gillett, 2008). Expert views reflect this, with 18 experts interviewed in Garrett and McCulloch (2022) overall identifying bottom trawling as the most harmful type of fishing from a welfare and environmental point of view.


As with many fishing welfare reforms, though they are likely beneficial for fish welfare, none of these were established for that reason. Restrictions on bottom trawling and dredging are well within the Overton window, and there are some precedents for limited bans on these practices. As mentioned, The Scottish National Party and Scottish Greens coalition have pledged to ban trawling in 10% of Scottish waters (Edwards, 2021). Furthermore, a type of trawling called pulse trawling that uses electric pulses to stun the fish was banned in UK waters in 2021 (Embury-Dennis, 2021). Finally, bottom trawling was recently banned in 4 of the 40 special marine protected areas in the UK (an area approximately the size of South Wales) (McVeigh, 2021a). There has been an uproar that the practice is still allowed in a majority of areas designated as special marine protected areas, and the apparent contradiction here could add leverage to a campaign against trawling (McVeigh, 2021c).


The net effect of these specific policies is not completely clear; trawling that might have happened in these protected areas might just be displaced to other areas, potentially resulting in the same number of fish killed. Pulse fishing does sound particularly gruesome, though this must be compared to the alternatives that are also highly problematic. Nevertheless these are positive signs that the government might be more receptive to calls for further restrictions.


Another factor that may motivate a ban or further restrictions is that bottom trawling is responsible for outsized carbon emissions of 600m - 1,500m tonnes. This is comparable to the total emissions from global aviation (McVeigh, 2021b; Sala et al., 2021). It happens because ocean floors are the largest store of carbon on the planet, and disturbing them can re-mineralise them into CO2 which contributes to both climate change and ocean acidification (Sala et al., 2021).


Because the government is already taking restrictions on the practice seriously and because of the strong environmental arguments for restrictions, this ask seems quite promising to us. Based on this preliminary assessment, we consider this the strongest ask in this area. We remain uncertain about whether it would be best to push for a full ban on trawling or whether more restrictions on the practice might be preferable because they are easier to achieve.


Reduce bycatch

Bycatch animals experience the same suffering and death that deliberately caught animals experience (even when thrown back their chance of survival is low), but in their case the death is for no reason at all since the meat is never used. Again, this ask has a strong environmentalist angle that could be leveraged.


There is some precedent for the UK acting to reduce bycatch; in 2015 the UK led an EU effort to ban the discard of unwanted quota fish in the waters (DEFRA, 2015). The idea behind this was that it would discourage bycatch because unwanted fish would have to be brought back, taking up room on the ship and counting towards quota limits.


However, this ban is regarded as a failure because it generated perverse incentives and the fishing industry was able to work around it. For example, the fishing industry was able to remove quotas for certain species, so that the discard of these fish would continue to be allowed. This removal of quotas is a bad consequence because it will generally result in more animals fished. They were also able to get exceptions to the ban based on throwback survival rates, which should not have been strong enough evidence to support this (Dutch Elasmobranch Society, no date). This offers a lesson into both the potential for unintended consequences of ostensibly beneficial interventions, and the power of the fishing industry in working around legislation designed to restrict it.


CRUCIAL CONSIDERATIONS


How feasible is stunning before slaughter of wild caught fish?

We expect that a significant amount of the value that comes from work on the subject will ultimately come from encouraging the development of stunning before slaughter of wild caught fish. This is technologically and economically difficult. Since the government is very unlikely to force anyone to adopt changes that they cannot realistically afford, technological developments to make stunning before slaughter feasible in fisheries is a plausible bottleneck to impact.


The ‘Humane slaughter prototypes’ subsection discusses examples of how this might be implemented. However, many of these prototypes are much more expensive than current fishing practices, and may have additional problems that would need to be worked out before widespread adoption. There is then a real outstanding question about how feasible and economically viable these technologies are.


Having said this, there did not seem to be good reason to think that the remaining scientific and technological problems in this area are insurmountable. Stunning machines are being used and studied in aquaculture contexts, so the outstanding problems just concern adapting these to the more complicated context of fishing vessels. One possible exception to this is stunning on board small vessels, for which bulky stunning machines might be impractical. However, small vessels may be able to use manual methods and, in any case, most fish in the UK are caught by large vessels that could easily fit stunning machines (interview proceedings).


Would legislation on this lead to more consumption of aquaculture fish?

Some of the possible welfare reforms we have been discussing would presumably result in an increase in the price of wild caught fish meat because they would increase the cost to producers. A risk of this is that it might shift consumption to fish raised in aquaculture, because aquaculture would not have to implement these welfare reforms, and so would become cheaper in many cases.


If people just substituted by eating proportionately more fish from aquaculture, this would likely not be an effective ask. This might be especially worrying because aquaculture could result in more fish suffering because fish are raised in low welfare conditions for their whole lives, rather than just being subjected to particularly painful conditions during slaughter as is the case with wild caught fish.


It might be thought that aquaculture and wild caught fish would be easy substitutes, since the product is fish meat in both cases. Whether aquaculture and wild caught fish are fact substitute goods depends on location and species, however, in general they are not (Bjørndal, 2016). This may be because wild caught fish already have a higher price point and are marketed as premium products, or because only some species are raised in aquaculture (interview proceedings). Having said this, Scottish farmed salmon is somewhat of an exception in that it is generally regarded as a premium product. Its price point is higher on average than for the other main countries that practise salmon farming (Griggs, 2022).


Schlag and Ystgaard (2013) discuss how public perceptions of aquaculture and wild caught fishing differ. In general there is a much more positive view of wild caught fishing, with wild caught fishing being viewed as a premium product and more associated with words like ‘local’, ‘fair’ and ‘natural’.


Another reason that this may not happen is because fish meal and fish oil from wild caught fish is a significant proportion of the diet of fish in aquaculture. This means that, as demand for aquaculture rises, demand for wild caught fish to feed them also tends to increase. It also means that if the price rises for wild caught fish, the cost for aquaculture will also rise because of the increased cost to producers of supplying fish meal and fish oil, further tying the performance of the two industries together.


On the other hand, if aquaculture producers are able to effectively substitute another form of feed, this may not be the case. Most feeds that might be substituted would cause less direct suffering than fish meal and fish oil, but an important exception would be if insects were substituted for fish meal and fish oil (Kessler, 2020).


Population dynamic effects on wild fishes

There are two key ways in which improving the welfare of wild-caught fish would also reduce human impacts on the populations of wild fish and other animals. Firstly, if the government imposes a new legal requirement to reduce bycatch, the mortality of non-target wild fish and other animals would decrease. This may cause an increase in the population numbers of these non-target animals, although such an increase would depend on the particular ecological context (Zhang, Chen and Ren, 2016; Zhou et al., 2019). Secondly, if the fishing industry adopts practices that incidentally improve both fish welfare and meat quantity – for example, by reducing the amount of fish flesh that is too damaged to be consumed as meat – this could lead to an overall lower catch and, therefore, reduce the fishing mortality of the targeted fish species. This might also cause an increase in the population numbers of the target fish species. Both of these causal chains could lead to further reductions in suffering caused directly by fishing activities. However, due to predation and other complex ecological interactions, the effect on overall suffering would be uncertain (Tomasik, 2015b; Delon and Purves, 2018).


There are also some ambiguous ways in which improving the welfare of wild-caught fish would affect the populations of wild fish and other animals. If the industry adopts practices that improve both fish welfare and meat quality, such practices may reduce the amount of fish flesh that is wasted. Conversely, such practices may also increase the value of fishing activities, and this incentive may cause fishing efforts to increase. Also, if the industry adopts practices that improve fish welfare, such practices might change the industry's broader fishing patterns. For example, there might be changes in fishing methods, technologies aboard the vessels, and the distribution of fishing effort in space and time. These changes might cause the overall catch to increase, decrease, or change in species composition. These effects would have profound impacts on the lives of some individual fish and other wild animals. However, at the level of the population (aggregate suffering), there is no clear reason to believe that these effects would cause a major overall increase or decrease in suffering.


Overall, we believe that improving the welfare of wild-caught fish would affect the lives of wild fish and other animals, but there is no strong evidence to suggest that these effects would be strongly positive or negative for welfare. Given this lack of evidence, we believe that this ask is worth pursuing on the basis of the strong, positive improvements of the welfare of caught fish.


A comparison between counterfactual causes of death in the wild

It is also important to consider the counterfactual cause of death that fish might have suffered otherwise. Fish will likely die painfully in the wild. This should make work to reduce the number of fish caught relatively less important, because fish are dying painfully in any case, and so what matters is only if one method is less painful than another (Tomasik, 2015a). This is a very difficult comparison to make and a full catalogue of the harms of death of wild fish is beyond the scope of this report.


A further complication is that fish killed during fishing otherwise live longer lives before dying from another cause. If their life quality during this time is positive, this would make an early death from fishing relatively worse. If their life quality during this time is negative, this would make the early death from fishing relatively better. Again, considering the quality of life of a variety of species of fish in the wild is beyond the scope of this report.


An answer (even an approximate answer) to this question would take considerably more research. We think the most plausible effect of this consideration is to make interventions to reduce the number of fish caught relatively less exciting, but potentially still very promising.


Thankfully, this consideration only applies to interventions that reduce the number of fish caught. It does not apply to interventions that only increase the relative humaneness of the deaths of the fish who are caught. As such, it does not apply to many of the possible interventions in this space, but it does apply to efforts to reduce bycatch and to a ban on bottom trawling and dredging.


A declining industry?

The wild fish catch of the UK has been declining steadily, but not precipitously, since the 1930s. The 1930 total catch in British waters was 1,094 metric tonnes and the 2018 catch was 429 metric tonnes, with the total declining every decade except for 1960-1970 (Marine Management Organisation, 2021). Additional fish amounting to 200,000 to 300,000 tonnes may be caught by British fishers in other territorial waters (Kay, 2021). The fishing industry in the UK has shrunk from around 20,000 fishers and 7,700 fishing vessels, to around 11,000 fishers and 5,700 vessels in 2021 (Marine Management Organisation, 2021). This is also the trend globally, with catches declining since the mid 1980s (Pauly and Watson, 2003).


Meanwhile, the aquaculture industry has been the fastest growing food production system for decades, growing at an annual rate of 8.4% worldwide (Österbloma and Jouffray, no date). UK aquaculture – dominated by Scottish salmon and trout farming – is no exception to this trend. It plans to double the economic contribution of the industry by 2030 (McConnell, 2018). Seafish predicts that the aquaculture industry will account for 62% of British fish consumption by 2030 (Kay, 2021). The primary market for Scottish salmon is the domestic market, with the sales accounting for 15% of all fish sales in the UK as of 2003 (Fofana and Clayton, 2003).


If the UK fishing industry is declining and being replaced by aquaculture, the value of asks to improve fish welfare, especially longer term asks, may be significantly reduced. This is because the value of the ask takes longer to be realised, and if it only affects a smaller industry, its value will correspondingly be reduced.


Despite a decline in the industry in the UK, there are some reasons to think this decline will be bounded, and a precipitous decline in the future should not be expected.

  1. Carnivorous aquaculture species such as salmon and trout are responsible for consuming a significant amount of fish meal and fish oil that is supplied through wild capture fisheries. This can be as high as 45% of the diet of Scottish aquaculture salmon (Tveterås and Tveterås, 2010). Globally, one third of all wild caught fish are fed to aquaculture fish or to other livestock (Tveterås and Tveterås, 2010). This would suggest that the rise of aquaculture might not be such a detriment to wild caught fisheries. However, fish meal may be imported from elsewhere rather than produced domestically: according to Seafood Source, in 2010, 135,400 tonnes of fishmeal were used in the UK, with 97,400 tonnes of these being imported and the remaining 38,000 tonnes produced in the UK (Seafood Source, no date). Exports to Peru are responsible for the bulk of UK fishmeal imports at 33,600 metric tonnes, followed closely by Demark at 29,700 tonnes, then Germany at 14,900 tonnes, Ireland 10,900 tonnes, Norway at 3,600 metric tonnes, and finally Iceland at 2,800 metric tonnes (Seafood Source, no date).

  2. Ultimately, the biggest bottleneck is a collapse of commonly fished wild fish populations (Gregory and Grandin, 1998). Therefore, if the number of fish killed by the fishing industry decreases, the populations will increase accordingly, incentivizing more fishing. This suggests that if there is not a further precipitous decline in wild fish populations, we should not see precipitous declines in fish catches.


CONCLUSION AND REMAINING UNCERTAINTIES


The scale and neglect of the welfare of wild caught fish is staggering, and it is worthwhile to make forays into work on the subject. Though in fisheries fish are only under control of humans for a short time at the end of their lives, they are subjected to a staggering amount of suffering during this time. Further, the number of fish affected by fishing in the UK is much larger than the total number of farm animals in the UK.


Based on our research, we can recommend that organisations begin exploratory work on the subject. Based on preliminary research, our top recommendation in this area is to ban bottom trawling and dredging. The following asks were identified as more promising within this area:

  1. Ban live baiting

  2. Limit time out of water

  3. Reduce bycatch

In the longer term, the fishing exception to the Animal Welfare Act could be removed and humane slaughter could be required, dramatically increasing welfare for many fish. We remain uncertain about the timelines for humane slaughter and the relative strength of different interventions in this space, corporate work or further research.

Nevertheless, work on wild caught fishing represents a challenge for animal advocacy organisations. Welfare measures are more difficult to implement on board vessels, and the science and technology of them is still in its infancy. The topic has been less well explored than even neglected areas of animal agriculture like aquaculture. We appreciate that more research is needed on the subject, and not all animal advocacy organisations will be in a position to work on the subject. We are happy to work with any organisations interested in beginning work on wild caught fishing, to more confidently identify the highest priority interventions in this space.


This report has focused on the UK, much of the reasoning and details (with the notable exception of specifics around animal welfare legislation) applies to other countries.


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