FISH WELFARE ON SCOTLAND’S SALMON FARMS A REPORT BY ONEKIND

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CONTENTS

1 INTRODUCTION 2 6.3.1 Increased aggression 26 6.3.2 Increased spread of disease and parasites 26 2 SALMON SENTIENCE 6.3.2 Reduced water quality 26 AND INDIVIDUALITY 4 6.3.4 Issues with low stocking densities 27 2.1 Fish sentience 5 6.4 Husbandry 27 2.2 Atlantic salmon as individuals 5 6.4.1 Handling 27 6.4.2 Crowding 28 3 ATLANTIC SALMON LIFE CYCLE 6 6.4.3 Vaccination 28 3.1 Life cycle of wild salmon 6 6.5 Transportation 28 3.2 Life cycle of farmed Alantic Salmon 6 6.6 Failed smolts 29 6.7 Housing 20 4 SALMON FARMING IN SCOTLAND 8 6.8 Slaughter 31

5 KEY WELFARE ISSUES 10 7 MARINE WILDLIFE WELFARE IMPACTS 32 5.1 High mortality rates 10 7.1 Wild salmon and trout 32 5.2 Sea lice 11 7.2 Fish caught for salmon food 33 5.2.1 How do sea lice compromise 7.3 Seals 33 the welfare of farmed salmon? 11 7.4 Cetaceans 34 5.2.2 How are sea lice levels monitored? 12 7.5 Crustaceans 34 5.2.3 How severe is sea lice infestation in Scotland? 13 8 FUTURE CHALLENGES 35 5.3 Disease 14 8.1 Closed containment 35 5.3.1 Amoebic Gill Disease 15 8.2 Moving sites offshore 35 5.3.2 Cardiomyopathy Syndrome 15 5.3.3 Infectious salmon anaemia 15 9 ACCREDITATION SCHEMES 5.3.4 Pancreas disease 15 AND STANDARDS 36 5.4 Treatment for sea lice and disease 16 9.1 Certification in Scotland 36 5.4.1 Thermolicer 17 9.2 What protection do standards provide salmon? 36 5.4.2 Hydrolicer 17 9.2.1 Soil Association Organic standards 36 5.4.3 Hydrogen peroxide 17 9.2.2 RSPCA Assured 36 5.5 Cleaner fish 18 9.2.3 Code of Good Practice 37 5.5.1 Wrasse 18 5.5.2 Lumpsucker 18 10 LEGISLATION AND INSPECTION 38 5.5.3 Welfare of cleaner fish 18 10.1 Animal Health and Welfare 5.6 Escapes 21 (Scotland) Act 2006 38 10.2 The Welfare of Animals (Transport) 6 OTHER WELFARE ISSUES 22 (Scotland) 2006 39 6.1 Confinement 22 10.3 Aquatic Animal Health (Scotland) 6.1.1 Jellyfish and Algal Blooms 22 Regulations 2009 39 6.1.2 Predation 23 10.4 Aquaculture and Fisheries (Scotland) Act 2013 39 6.1.3 Weather 24 10.5 Inspections 39 6.1.4 Unnatural behaviours 24 6.2 Health defects 24 11 RECOMMENDATIONS 40 - 45 6.3 Stocking density 26

Published by OneKind 2018 Registered charity no. SC041299 RESEARCH AND REPORT Sarah Allen [email protected] 50 Montrose Terrace, Edinburgh, EH7 5DL DESIGN John Nicol [email protected] www.onekind.scot 1: INTRODUCTION

The industry is growing fast, with the Scottish Scotland is the Government committed to targets of production for largest farmed over 45 million salmon in 2020 and over 65 million in 2030, from a 2016 level of 35 million individuals. salmon producer Yet the industry is facing major challenges. The impacts in the EU and the of salmon farming on Scotland’s biodiversity and natural environment are increasingly well - documented third largest in and debated, but the welfare of the tens of millions of the world. fish involved in the industry is often forgotten.

This report focuses on the welfare of fish on salmon farms specifically because they dominate the Scottish aquaculture industry, making up more than 90% of aquaculture production. Protecting the welfare of these

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fish and preventing suffering is a moral imperative, but Furthermore, the industry’s Code of Good Practice it is also critical to the viability of the industry itself. (2015), that guides 90% of salmon farming production, Consumers expect healthy, happy and sustainable fish, notes that “Fish health and welfare is paramount at and poor welfare also leads to direct economic losses. each stage of production”.

This has long been recognised, with a 1995 review This report does not attempt to provide a concluding that “to maintain salmon farming as a viable comprehensive review of the environmental impacts industry it is necessary to continue to focus on the well of salmon farming, which are well highlighted by other - being of fish” (Juell, 1995). Indeed, industry leaders groups such as Salmon and Trout Conservation Scotland themselves recognise this. For example, Marine Harvest and the Scottish Salmon Think - Tank. However, there (2018a) describes it’s focus as always being on “health are many overlaps between welfare and environmental and welfare” and note that it “makes no commercial concerns, such as sea lice, escapes, and the use of sense to neglect the welfare of fish and to employ acoustic deterrents, which we explore in detail here. anything but the best husbandry techniques”.

FISH WELFARE ON SCOTLAND’S SALMON FARMS Page 3 2: SALMON SENTIENCE AND INDIVIDUALITY iStock Prefect Stills iStock Prefect photograph by by photograph Page 2 FISH WELFARE ON SCOTLAND’S SALMON FARMS It is easy to forget about the individual 2.2 Atlantic salmon as individuals when discussing salmon farming, Atlantic salmon have been shown to have unique personalities, with individuals varying in their avoidance especially given the sheer scale of the behaviour. Church and Grant (2018) exposed fish to a industry. It is, however, the case that novel object and measured their responses, finding that each salmon farmed in Scotland is a some individuals were bolder, and quicker to approach unique individual, capable of suffering. the object than others, who were warier.

Atlantic salmon are also unique in their appearance. 2.1 Fish sentience They have unique spot patterns on their gill coverings It is now widely acknowledged that fish are sentient which are distinct enough that humans can distinguish animals, capable of feeling pain. It is known that the between individuals (Stien et al. 2017). Salmon can pathways for feeling pain in fish share similarities also distinguish between friend and foe, with research with those in humans (Brown, 2015). Sneddon showing that they use smell to differentiate between (2015) compared the ability to feel pain between fish individuals (Brown and Brown 1992). and terrestrial mammals and found that they both demonstrated the same evidence for feeling pain. Salmon can use their skin colour to communicate. This includes possessing nociceptors (pain receptors), Fish that are losing territorial disputes become darker moving away from a noxious stimulus and paying a in colour, a change that was found by researchers cost to avoid an adverse stimulus. An example of fish to reduce the number of times the “loser” fish was feeling pain can be seen in rainbow trout (Oncorhynchus attacked (O’Connor et al. 1999). It is therefore likely mykiss) - a species in the same family as Atlantic salmon that darkening in colour acts as a sign of submission (Salmo salar), the Salmonidae. Research has shown that, from the losing fish, which prevents them from receiving if a chemical is injected into their lips, they rub their further damage from their aggressor (O’Connor et al. lips on the gravel and against the side of the tank, and 1999). this behaviour is reduced once provided with morphine (Sneddon, 2003). Within aquaculture, salmon vary in their physical appearance and behaviour, with some fish being A number of studies have clearly demonstrated that described as “loser fish”. These fish can make up salmon feel pain. For example, stimulation of the tail nearly a quarter of stocked salmon globally, and are base of Atlantic salmon results in electrical stimulation characterised as being smaller, anorexic, and less active. of an area of the brain known as the telencephalon, On investigation of these “loser fish”, Vindas et al. which is associated with emotion and pain perception (2016) found that they exhibit behaviour and serotonin (Nordgreen et al. 2007). Salmon also change their levels that could be described as a “depressive state”. behaviour in response to an adverse experience. Helen - Bjørge et al. (2011) found that Atlantic salmon change their swimming and feeding behaviour after iStock Prefect Stills iStock Prefect suffering from peritonitis following vaccination. photograph by by photograph FISH WELFARE ON SCOTLAND’S SALMON FARMS Page 5 3: ATLANTIC SALMON LIFE CYCLE

3.1 Life cycle of wild Atlantic salmon 2016). Stripping can be damaging to fish as it involves Atlantic salmon are anadromous fish that, in the removal from water, handling, and requires placing a wild, migrate thousands of miles in their lifetime. strong pressure on the fish, which has the potential to Atlantic salmon that hatch in Scotland have been cause internal bleeding (Stevenson, 2007). shown to migrate as far as the Davis Strait, which is between Greenland and the Canadian Arctic (Scottish Causing damage to broodstock does not just Government, 2018). compromise the health of these individuals. In salmon, it has been shown that any stress that the mothers face Atlantic salmon start their lives in freshwater as eggs, can have a detrimental impact on their offspring, for which hatch to become alevins (fish still with their yolk example through reducing their feeding success and sac attached). They then subsequently become fry, increasing the amount of attacks they face (Eriksen and then parr. When they are physiologically ready for et al. 2011). migration to seawater, they become known as smolts. Once in seawater, Atlantic salmon can spend up to three Once eggs have been fertilised, they are kept in years at sea, though some salmon- known as grilse - freshwater hatcheries. Once the eggs hatch, the fish go travel back to freshwater after only one year at sea. through successive stages known as alevins, fry, and The migration of salmon upstream is an incredible feat, parr. These young fish are kept in freshwater cages or often requiring salmon to leap up weirs and waterfalls. tanks until they undergo a process called smoltification, Amazingly, salmon often return to their natal rivers to which is when their body changes to adapt to saltwater. spawn, largely as a result of an excellent sense of smell Once fish have undergone smoltification, they are and their ability to use the Earth’s magnetic field for known as smolts. navigation during migration (Lohmann et al. 2008). It is smolts that are then transported to sea cages, 3.2 Life cycle of farmed Atlantic Salmon where they will typically spend one or two years at sea Farmed Atlantic salmon start their lives in freshwater before being slaughtered. In 2016, 43 million smolts hatcheries. Most eggs are obtained from overseas, in were put to sea in Scotland (Marine Scotland Science, 2015 over 90% of eggs used in the Scottish salmon 2016). farming industry came from other countries, with the majority originating from Norway.

There are, however, sites in Scotland that produce salmon eggs. Salmon that are used to produce eggs or sperm are known as “broodstock”. In 2016 there were three sites which housed broodstock in Scotland. Broodstock undergo stripping (stroking the abdomen of fish) to obtain either sperm or eggs. In 2016, 1,695 fish were stripped in Scotland (Marine Scotland Science,

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How many farmed salmon are there?

Data on the number of salmon on farms in Scotland We have therefore estimated the number of individual is only available in weight (tonnes) from Scottish salmon from weight data. To do this we calculated upper Aquaculture, a website established by a partnership of and lower estimates of numbers. The higher estimate Government agencies. This data is used throughout is calculated using the assumption that all salmon on this report, however, given that salmon are individual farms weigh 1 kg (Salmon and Trout Conservation, sentient beings we consider it inappropriate to consider 2017), and the lower estimate assumes that all salmon them purely in terms of weight. weigh the average harvest weight following two years at sea of 5 kg (Scottish Government, 2016).

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Salmon farming in Scotland is a new industry, only starting in the 1970s. It has rapidly increased in size, salmon farms, with an increase in large scale production and Scotland is now the largest producer of farmed overseen by large companies, with a decline in the Atlantic salmon in the EU, and the third largest globally, number of active companies producing salmon, from after Norway and Chile. In 2016, there were 253 132 companies in 1993, to 10 in 2016 (Marine Scotland seawater farms, 136 of which produced fish, producing Science 1993 - 2016) (Figure 1). 35 million fish. These sites are located along the west coast of Scotland, and along Orkney and Shetland In 2016, an industry working group published a strategy (Figure 2). aimed to increase aquaculture by growing production in new and expanded farm sites (Scotland Food and The majority of salmon farms in Scotland are operated Drink, 2016). The industry aims to double the value of by five companies: Marine Harvest, Scottish Sea Farms aquaculture to the economy by 2030. The targets set Ltd., The Scottish Salmon Company, Cooke Aquaculture are 210,000 tonnes of finfish (“true” fish as opposed to and Grieg Seafood Ltd. In total, 15 companies were shellfish) by 2020, and 350,000 tonnes by 2030. This recorded as operating in 2016, although only 10 of is estimated to be a target of over 65 million individual these were recorded as being active. Overall, there is salmon by 2030. a shift away from independent companies operating

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20 NUMBER OF COMPANIES PRODUCING ATLANTIC SALMON SALMON ATLANTIC PRODUCING NUMBER OF COMPANIES 0 YEAR

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 1993

FIGURE 1. The number of active companies producing Atlantic Salmon in Scotland between 1993-2016. Source: Marine Scotland Science Fish Farm Production Surveys

Page 8 FISH WELFARE ON SCOTLAND’S SALMON FARMS FIGURE 2. Locations of salmon farms in Scotland between 2013 and 2017. Source: Scotland’s Aquaculture website 5: KEY WELFARE ISSUES

5.1 High mortality rates Mortality rates on Scotland’s salmon farms are high. For As well as overall mortality levels, it is possible to example, of smolts put to sea between 1984 and 2014, ascertain mortality rates within a month on each farm between 5 and 40% did not survive the full production in Scotland. Our analysis of this shows that monthly cycle (Marine Scotland Science, 1984 - 2016) (Figure 3). mortality as a percentage of on-site biomass ranged Looking at this on a more recent scale, of the 48 million from 0% to 94% across sites between 2013 and 2017. smolts that were put to sea in 2014, 9 million (26.7%) During this period, the highest monthly mortality was died during the two-year production cycle. at Cole Deep salmon farm, where 640,812 kg (an estimated 128,000 to 641,000 fish) died in December In 2016, mortality rates were equally high, with 2015. suggestion that 10 million salmon died prematurely on seawater sites in 2016, and this is estimated to have Some may argue that mortality is not a welfare issue increased to over 11 million in 2017 (Marine Scotland in itself, but an inevitable consequence of raising fish Science, 2016, Scotland’s Aquaculture, 2018). in captivity. Ellis et al. (2012) refute this claim, as well as other misconceptions about mortality of farmed fish. They note that, whilst some mortality is inevitable (a rate of around 1.5%), higher mortality rates can indicate suffering. Deaths are rarely instantaneous, being due to conditions such as disease and sea lice. 45

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20 MORTALITY (%) MORTALITY 15

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0 1984 1986 1990 1992 1994 1996 1998 2000 2002 2004 2006 2010 2012 2014

SMOLT YEAR OF INPUT

FIGURE 3. Mortality rates (%) of smolts put to sea between 1984 and 2014 Source: Marine Scotland Science 1984-2016

Page 10 FISH WELFARE ON SCOTLAND’S SALMON FARMS 5.2 Sea lice Sea lice are natural occuring parasitic copepods (small, As the skin is an important component of water-dwelling crustacea) that feed on the skin, scales, osmoregulation, such damage disrupts water and salt tissues and mucous layer of fish. There are two types of concentrations within the fish. This is because it reduces sea lice that infect farmed salmon: Caligus elongatus the efficacy of the skin as a barrier, meaning that a and Lepeophtheirus salmonis. The most prevalent type greater amount of water leaks from the fish into the in Scotland is L. salmonis - the salmon louse - which environment (Thorstad et al. 2015). currently causes severe problems to farmed salmon. Sea lice can also hinder swimming ability, and act as 5.2.1 How do sea lice compromise the welfare vectors for transmission of diseases such as Infectious of farmed salmon? Salmon Anaemia (ISA) (Wagner et al. 2003, Nylund et al. 1994). Through feeding on the skin and tissues, sea lice cause serious damage to the health of salmon and can Not surprisingly, because of the damage they cause, ultimately cause death. high numbers of sea lice can cause high levels of stress. It has been shown that heavy infestation of sea lice Sea lice create physical damage to the skin and tissue leads to increased levels of the stress hormone cortisol, of salmon, causing the development of lesions, and the which can last up to three weeks post infestation loss of scales. So - called “death crowns” can also be (Mustafa et al. 2000). Chronic stress compromises created by sea lice, where the flesh on the head of the the welfare of fish by reducing their growth rate and fish is exposed. For example, Fish Health Inspectorate increasing the likelihood of further infection. reports (2017) document seeing fish with “severe lice damage to their heads”. Given all these factors, sea lice can be fatal to salmon (Thorstad and Finstad, 2018).

Fish Health Inspectorate Fish Health Inspectorate

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5.2.2 How are sea lice levels monitored? The salmon farming industry sets its own thresholds for Critically, there appears to be no scientific or fish welfare sea lice, under the Code of Good Practice for Scottish basis. Trigger levels also only relate to one stage of the Finfish Aquaculture (2015). These levels are criteria for life cycle of sea lice, the adult female. This is because treatment and are set at an average of 0.5 to 1 adult they indicate the potential for further spread of sea lice. female lice per salmon, depending on the time of year. Focusing only on adult females means that trigger levels ignore male sea lice, and other life stages. This is despite TABLE 1. Code of Good Practice sea lice trigger levels by time of year. Source: Code of Good Practice for Scottish Finfish evidence that other stages of sea lice - not just adult Aquaculture (2015) females - can seriously compromise the welfare of fish (Thorstad and Finstad, 2018).

TIME OF YEAR TREATMENT TRIGGER LEVEL (average female louse) Research by the Salmon and Trout Conservation Trust (2018) documents that there is very little evidence that 1st February - 30th June 0.5 effective action is taken once Scottish Government sea 1st July - 31st January 1.0 lice trigger levels are exceeded by salmon farms. They also note that, between the introduction of the new trigger levels in June 2016 and up to November 2017, The Scottish Government also has sea lice trigger levels, only one enforcement notice was given, despite the fact which were introduced in June 2016 and are much that more than 20 sites breached trigger levels of eight higher than those set under the Code of Good Practice adult female lice in 2017. (2015). These are average adult female sea lice counts of three (which means that sites have to produce a sea lice “action plan”), and eight (at which point enforcement action is taken).

Page 12 FISH WELFARE ON SCOTLAND’S SALMON FARMS 5.2.3 How severe is sea lice infestation in Scotland? Fish Health Inspectorate reports (2017) show that 48% or welfare issues associated with sea lice, or the early of visits to seawater sites in 2017 had recorded sea lice harvesting of stock as a method to tackle sea lice). problems within the last four years (defined as a site Documentation released under Freedom of Information having one of the following: sea lice levels over trigger requests show that over 70 salmon farms exceeded sea levels, completing two consecutive treatments that lice thresholds for treatment, in 2017. The worst was failed to reduce lice numbers, physical damage North Havra salmon farm, which had average female lice counts of up to 29.5 per individual (Table 2).

TABLE 2. Largest recorded sea lice averages in 2017. Source: Published Freedom of Information request, reference FOI/17/02754

SITE NAME COMPANY MAXIMUM AVERAGE SEA LICE LOAD North Havra Grieg Seafood Ltd. 29.5 Score Holms Grieg Seafood Ltd. 22.4 Dury Voe Scottish Sea Farms Ltd. 22 Spoose Holm Grieg Seafood Ltd. 20.6 Clashnessie Bay Loch Duart Ltd. 20.1 Quarry Point The Scottish Salmon Company 19.9 Teisti Geo Scottish Sea Farms Ltd. 18.4 North Papa Grieg Seafood Ltd. 16.6 West of Burwick Grieg Seafood Ltd. 16.2 Langa Isle (East) Grieg Seafood Ltd. 15.4

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5.3 Disease Farmed salmon can suffer from a wide range of There is now increased understanding of the link diseases. This is not surprising given fish farms inevitably between stress and disease, with stressed fish being create the perfect conditions for diseases to spread, increasingly susceptible to infection (Tort 2011). Given with many fish kept in high densities. Environmental that salmon farming exposes salmon to a great number conditions can also increase the prevalence of disease, of stressors (for example handling, crowding and with warmer waters leading to new and complex gill treatment) it is again not surprising that they suffer issues, and reducing generation times for disease and from numerous diseases. sea lice.

Farmed salmon in poor condition Fish Health Inspectore

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The most common diseases suffered by farmed salmon in Scotland are discussed below.

5.3.1 Amoebic Gill Disease 5.3.3 Infectious Salmon Anaemia Amoebic Gill Disease (AGD) is caused by a parasitic Infectious Salmon Anaemia (ISA) is characterised by amoeba Neoparamoeba perurans. Infestation by N. severe anaemia and haemorrhage in internal organs. It perurans can cause an increase in mucous production in is a severe disease which currently does not have a cure, the gills of salmon, which causes respiratory problems, meaning that all infected fish must be slaughtered. In and can cause death through asphyxiation. AGD is still March 2018, at Greshornish salmon farm, 6.3% of the a major cause of mortalities in Scotland and has been salmon on the site died as a result of anaemia. As there known to cause up to 50% losses on salmon farms were an estimated 430,000 to 2 million fish on this (Scottish Government, 2018). In 2016, at the salmon site in this month, this means an estimated 27,000 to farm Raineach, 116,551 salmon died over a period of 130,000 fish died from ISA (Marine Harvest, 2018b). 10 weeks as a result of AGD (Fish Health Inspectorate, 2016). 5.3.4 Pancreas Disease Pancreas Disease (PD) is caused by the salmonid 5.3.2 Cardiomyopathy Syndrome alphavirus (SAV) and causes necrosis of pancreatic Cardiomyopathy Syndrome (CMS) affects the heart tissues. Infected fish have been shown to be in poor muscle of infected fish, creating heart lesions and condition, being thin and lethargic. Kilburn et al. (2012) consequently reducing their cardiovascular capacity analysed mortalities caused by PD in Scotland and (Garseth et al. 2017). This leaves fish fragile and weak found that there has been an increase in the prevalence and means they are less able to cope with any further of PD in recent years. In 2017 2,000 salmon died as a stress. CMS has been recorded as the cause for many result of PD on the Plocrapol salmon farm (Fish Health mass mortalities, including the death of 68,265 salmon, Inspectorate, 2017). over a period of 17 weeks, on Winna Ness salmon farm (Fish Health Inspectorate, 2016).

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5.4 Treatment for sea lice and disease Traditionally, the salmon farming industry has This is due in part to the treatment process itself, but it’s relied on the use of insecticides (chemicals) such as also because fish that undergo treatment already have azamethiphos and emamectin benzoate to treat sea compromised health as a result of sea lice or disease, lice and other diseases. Whilst these are still used, their making them more vulnerable to stress. Marcos-Lopez use is being reduced following emergence of sea lice or et al. (2017) discuss this in reference to treatment for disease resistance to these chemicals (Aaen et al. 2015). AGD. They found that fish suffering from AGD have compromised gills, making them more susceptible to Nonetheless, chemicals are still used to tackle sea lice damage during treatment. and disease, and these can compromise salmon welfare. One example of this is Salmosan, which is the patented There is also no guarantee that treatment will work. name for the insecticide azamethiphos. Salmon are For example, in 2016 it was noted that after treatment exposed to this chemical as part of a bath treatment, with freshwater (i.e. hydrolicer treatment) for sea lice which involves crowding salmon within a small area at Raineach salmon farm, sea lice resettlement was using a tarpaulin, and exposing them to chemicals. quick (Fish Health Inspectorate, 2016). At Ardintoul, in Salmosan treatment led to the death of 20,718 fish at 2016, it was noted that “the alphamax and peroxide Gob a Bharra in 2017 (Fish Health Inspectorate, 2017). treatment was ineffective” (Fish Health Inspectorate, 2016). Given the increased resistance to chemical treatment, combined with environmental concerns over the impacts of such chemicals on the wider environment, the salmon farming industry is increasingly using new treatments for sea lice and disease.

Unfortunately, many of these new treatments can seriously compromise the welfare of farmed salmon, often leading to mass mortality events. Bui et al. (2017) state:

“Among aquaculturists, there is an unspoken understanding that it is the treatment, and not the sea lice, that causes many of the large-scale mortality events”.

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5.4.1 Thermolicer 5.4.2 Hydrolicer The Thermolicer is a new mechanical treatment that The Hydrolicer works in a similar way to the Thermolicer, uses a sudden rise in water temperature to kill sea but instead of warm water, freshwater jets are used to lice. The process involves using warm water to remove dislodge sea lice. Freshwater is used as sea lice are not sea lice from salmon. Salmon are first “crowded” into adapted to survive in it, and therefore should detach one area, so that they can be pumped up into the once exposed to it. Reports from Scottish salmon farms Thermolicer. Crowding is recognised as a stressful show that treatment using the Hydrolicer can result in process and can expose the fish to harsh, abrasive eye damage. Hydrolicer treatment also led to the death surfaces, which can cause them physical damage. of 1,851 fish at the fish farm Kenmore (Loch Torridon) in They are then exposed to water of up to 34oC, which is June 2017. outside of their normal temperature range. Indeed, it has been found that temperatures above 22.5oC cause 5.4.3 Hydrogen peroxide stress to Atlantic salmon (Environment Agency, 2008). Hydrogen peroxide is exposed to fish as a bath In addition, salmon are not used to rapid temperature treatment, to treat both sea lice and amoebic gill changes, which cause additional stress. When they have disease. It is praised as an environmentally friendly finished being exposed to the warm water, they are treatment (Solvay,2018), though it is far from welfare - pumped back into their cages. Some are then checked friendly, as hydrogen peroxide, more commonly known for sea lice, which involves removal from the water, a as bleach, is a chemical irritant. Studies have shown that further stressor. exposure to hydrogen peroxide causes stress (Vera and Migaud 2016) and can cause damage to the mucosal Scientists at the Norwegian Veterinary Institute found barriers of the gills, skin and gut. The latter has been that treatment using the Thermolicer resulted in fin shown to prevail for up to two weeks post treatment; damage, snout injuries, and scale loss (Grøntvedt et al. fish are highly susceptible to further infection during this 2015). time.

Mass mortalities of over 90,000 fish associated with On Scottish salmon farms, hydrogen peroxide treatment Thermolicer use have been documented in recent years, has caused mass mortalities. For example, in November including an incident at Score Holms in 2017, where 2015, 92,000 salmon died at the site Sgian Dubh 10,619 fish died following Thermolicer treatment. following hydrogen peroxide treatment (Fish Health Inspectorate, 2016). Following hydrogen peroxide losses at the site North Papa, vets documented salmon as having “bleeding around the heart, which is attributed to increased stress” (Fish Health Inspectorate, 2017).

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5.5 Cleaner Fish Another alternative “treatment” for sea lice that is (Ctenolabrus rupestris) and corkwing wrasse now prevalent across Scotland is the use of “cleaner” (Symphodus melops) are sometimes used. fish – lumpsucker (Cyclopterus lumpus) or species of Wrasse exhibit winter dormancy, which means they do wrasse - to pick off and eat sea lice from salmon. It is not feed below 6oc. This reduces their effectiveness recommended that there is one cleaner fish for every as cleaner fish in the winter months, which partially 25 salmon (Marine Conservation Society, 2018). The explains why the industry is shifting towards using use of cleaner fish began in the UK in the late 1980s lumpsuckers instead. but has only become widespread in recent years. It is expected that by 2020 10 million cleaner fish will be 5.5.2 Lumpsucker used in Scotland and that by 2019 all cleaner fish will be Lumpsuckers are also known as lumpfish. They lack obtained from a farmed source (Marine Conservation a swim bladder, so instead have a suction cup which Society, 2018). they use to stick to surfaces. Unlike wrasse, lumpsuckers will feed below 6oc, feeding to 4oc. This makes them In 2016, three hatcheries in Scotland produced 118,000 preferable to the industry over wrasse, though there is wrasse, and seven hatcheries produced 262,000 some debate over the effectiveness of lumpsuckers as lumpsuckers. The remaining cleaner fish used by the cleaner fish. industry are wild caught, with inevitable impacts on wild populations and welfare issues relating to how they are 5.5.3 Welfare of cleaner fish caught, handled, and transported, and how well suited As noted by the Farm Animal Welfare Committee they are to captivity. (2014a), cleaner fish experience the same welfare issues that farmed fish face. However, there is very little 5.5.1 Wrasse research into their biology and welfare in captivity, Within Scottish salmon farming, the most common though the University of Stirling is starting to research species of wrasse used is the ballan wrasse (Labrus cleaner fish behaviour in captivity (for example see bergylta), although others such as goldsinny Leclercq et al. 2018).

Ballan Wrasse iStock wrangel Lumpsucker iStock feathercollector

Page 18 FISH WELFARE ON SCOTLAND’S SALMON FARMS 5.5.3.1 Interactions with other fish Further high mortalities of cleaner fish have been seen Salmon are carnivorous, and can show aggression following disease outbreaks such as the outbreak of towards cleaner fish, and have been found to consume Viral Haemorrhagic Septicaemia (VHS), which occurred cleaner fish. Indeed, recommendations, including those in wrasse on salmon farms in Scotland, in 2012 of the Royal Society for the Prevention of Cruelty to (European Union Reference Laboratory for Fish Diseases, Animals (RSPCA) Assured standards, state that cleaner 2016). fish must only be introduced once salmon are satiated (full), to avoid salmon eating cleaner fish. It has also There is also a suggestion that cleaner fish may transfer been shown that cleaner fish compete with salmon for disease to salmon, although research into this is limited, access to food pellets (Imsland et al. 2014). with a report by the Norwegian Scientific Committee for Food and Environment (2017) concluding: Aggressive interactions can also work the other way “the disease status of wild - caught cleaner fish is, in around, with cleaner fish causing damage to salmon. In general, poorly known. Translocations of such fish may one incident documented in 2010, ballan wrasse caused result in the introduction of new pathogens to farmed eye damage to a number of salmon, which resulted salmonids”. in many salmon bleeding to death (Treasurer, 2013). Cleaner fish can also show aggression to each other. Cleaner fish can also suffer from health problems such For example, reports by the Fish Health Inspectorate as cataracts, with Powell et al. (2017) noting that show that aggression and cannibalistic behaviour have this is likely associated with rapid growth and dietary been documented in farmed lumpsuckers (Fish Health deficiencies. Fin damage has also been observed to Inspectorate, 2016). affect cleaner fish, which can lead to the development of fungal infection. 5.5.3.2 Health Cleaner fish on farms suffer from numerous diseases. Like salmon, cleaner fish can suffer high mortalities as Ironically, they too can experience severe sea lice a result of treatment. Wrasse have been known to die loads (Powell et al. 2017). Fungal infection is also a in large numbers following treatment, often as a result common cause of mortality in cleaner fish. Therefore, of over inflation of the swim bladder because nets to cleaner fish in salmon farms often have severely capture fish were raised too quickly (Treasurer, 2013). compromised health, which can lead to high mortality Lumpsucker can also suffer as a result of treatment. levels. According to the EU Reference Laboratory for Fish For example, at Caolas A Deas salmon farm, lumpfish Diseases (2016): were not removed prior to treatment, resulting in the “Cleaner fish mortalities in salmon farms are often high, death of 1,500 - 2,000 lumpfish per cage (Fish Health and very few cleaner fish presumably survive through Inspectorate, 2017). a full salmon production cycle. Losses of entire batches due to bacterial disease are also occasionally observed in cleaner fish farms”.

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5.5.3.3 Husbandry Cleaner fish have been documented to be easily In addition to consuming sea lice, cleaner fish need stressed and can respond negatively to routine supplementary food. It is also not the case that aquaculture practices. withdrawing extra food from cleaner fish will cause them to eat more sea lice. It is believed that wrasse are more sensitive than lumpsuckers to handling, though both will suffer Problems with providing supplementary food to cleaner when handled incorrectly. Leclrecq et al. (2014) found fish have been documented on salmon farms. Powell et that ballan wrasse exposed to 1-minute air exposure al. (2017) noted that around one third of lumpfish died had an increase in cortisol (stress hormone) levels by from starvation within a few weeks of being introduced up to 83.9%, compared to a resting rate. In 2016, into salmon cages. In 2017, at one salmon farm site it at a lumpsucker rearing unit, handling led to the was observed that there was an “increase in lumpsucker development of furunculosis (swollen areas on the skin mortality as fish were switched onto pelleted food and caused by a bacterial infection), due to the stress caused some of the smaller fish were unable to feed” (Fish by handling (Fish Health Inspectorate, 2016). Health Inspectorate, 2017).

Page 20 FISH WELFARE ON SCOTLAND’S SALMON FARMS 5.6 Escapes Over 30,000 salmon escaped from Scottish farms in 2017. The causes of these escapes vary, and include human error, weather, and predation. Between 2013 and 2017, the greatest cause of escapes was human error, which accounted for 31% of escape events (Figure 4). Unfortunately, the data collected on escapes is limited and gives very little information on the circumstances which led to fish escaping.

Chafe/Snag Equipment Damage Equipment wear and tear Hole in net Human error Net under water No actual escape of fish Other Predator Screen Failure Unknown Weather Wellboat/Boat collison

Figure 4. The causes of escapes between 2013 and 2017 Source: Scotland’s Aquaculture website

Escaped salmon have compromised welfare. They are fertilised eggs from removing the extra chromosome set not well-adapted to the wild, which means that they during development. Having this extra chromosome set. likely suffer. Despite this there is evidence that they Having this extra chromosome renders triploid fish can interbreed with wild individuals (Karlsson et al. sterile, meaning that they cannot interbreed with the 2016). This compromises the welfare of wild salmon, wild population. However, triploid salmon have been as it produces offspring that have reduced fitness. shown to have reduced welfare compared to their Furthermore, it has been suggested that escaped diploid counterparts. Evidence shows that triploid farmed salmon compete with wild salmon for food. salmon have increased prevalence of spinal deformities, One solution proposed to reduce the impact of escaped are often outcompeted by their diploid counterparts, farmed salmon on wild populations is to use triploid fish. and are more vulnerable to temperature stress (Fjelldal These are fish that have an extra set of chromosomes, and Handsen 2010, Carter et al. 1994, Fraser et al. meaning they have three sets instead of two. This is 2012). This means that often triploid salmon have a done using heat or pressure shock to prevent newly much higher mortality rate than diploids (Cotter et al. 2002).

FISH WELFARE ON SCOTLAND’S SALMON FARMS Page 21 6: OTHER WELFARE ISSUES

As well as the key welfare concerns above, which are perhaps the more pressing to fish welfare, other animal welfare issues are also caused by salmon farming in Scotland.

6.1 Confinement In the wild, salmon migrate thousands of miles. Farmed salmon are unable to do this, and other natural, innate behaviours, and instead have been shown to display unnatural behaviours. Furthermore, being enclosed means they cannot escape adverse events. These include predation, aggressive interactions from other fish, severe weather conditions, and exposure to jellyfish and harmful algal blooms. Farmed salmon can be exposed to these conditions for a long period of time, with individuals being held on seawater farms for up to two years.

6.1.1 Jellyfish and Algal Blooms Jellyfish harm salmon by causing gill irritation and decreasing water quality. Depending on their size, jellyfish can either damage fish from outside or inside the cages. One species of jellyfish that is small enough to enter salmon cages is Phialella quadrata, which has Salmon in cages. Fish Health Inspectorate been shown to cause gill damage, as well as acting as a vector for bacterial infection (Ferguson et al. 2010). These issues mean that jellyfish can cause high Other research has shown that the common jellyfish mortalities on salmon farms. In 2016, at Muck salmon (Aurelia aurita) causes severe damage to Atlantic farm, 37,880 salmon died following issues with lion’s salmon smolts that lasts up to 48 hours post-exposure mane jellyfish (Cyanea capillata). (Baxter et al. 2011). Furthermore, as noted by the European Food Safety Authority (2008), fish that come Similarly, farmed salmon are unable to escape when into contact with jellyfish cause themselves damage a harmful algal bloom occurs. Algal blooms cause through scratching the affected region on hard surfaces severe irritation to the gills of salmon and result in such as nets. deterioration of water quality. This can cause mortality rates of up to 100%. Bruno et al. (1989) reported that

Page 22 FISH WELFARE ON SCOTLAND’S SALMON FARMS Salmon in cages. Fish Health Inspectorate Moon Jellyfish iStock ginosphotos

phytoplankton blooms in Loch Torridon resulted in gill fish and because of the wild fish that aggregate around necrosis, leading to 550,000 fish dying. This is similar to salmon pens. a more recent event in 2016, where 520,000 fish died following a cyanobacterial bloom at Cliff Site freshwater Animals that predate farmed salmon include: Seals salmon farm (Fish Health Inspectorate, 2016). (common (Phoca vitulina) and grey (Halichoreus grypus)), seabirds (such as gannets, fulmars, shags), 6.1.2 Predation and other mammals (such as otters and mink). As well Confining salmon in one location makes them an easy as consuming salmon on fish farms, predators can also target for predation if a site is not properly protected cause physical damage through biting salmon through (using non-lethal, humane methods). Predators are the netting. attracted to salmon farms as a result of both the captive

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Salmon with physical damage following exposure to strong currents Fish Health Inspectorate

6.1.3 Weather Atlantic salmon within sea cages perform mass shoaling Harsh weather conditions can cause physical damage behaviour. Such behaviour does occur in juvenile fish, to farmed salmon and even death. Mortality is largely but in the wild does not tend to be performed by adults caused as salmon are pushed against the harsh surface in their seawater stage. of cages, causing wounds that can then become infected. In 2017, 23,657 fish died at South Sound 6.2 Health defects salmon farm because of physical damage following bad It has been shown that farmed salmon have a range weather (Fish Health Inspectorate, 2017). of defects that compromise their health and welfare. Cataracts are relatively common and can be as Bad weather can also prevent Fish Health inspectors prevalent as 80% in farmed salmon (Ersdal et al. 2001). and vets from visiting sites and assessing fish health and The causes of cataracts are likely multifactorial, and welfare. This is documented in Fish Health Inspectorate include nutritional deficiencies, rapid growth and water reports (2016), for example at Bight of Foraness salmon pollution (Rhodes et al. 2010, Waagbo et al. 1998 , farm in 2016, where the “site inspection could not Bjerkas et al. 2004). The development of cataracts be conducted due to weather conditions. [Inspectors] reduces the ability of salmon to find food, which in turn returned to site, however weather conditions compromises their development and growth. deteriorated again, so inspection had to be abandoned” (Fish Health Inspectorate, 2016). Spinal deformities are also prevalent in farmed salmon. It is suggested that these can be caused by genetics, 6.1.4 Unnatural behaviours parasites, nutrition, pollution, and injury during As a result of confinement, farmed salmon have been husbandry (Silverstone and Hammell 2002). Whilst wild shown to display behaviours they would not normally salmon do have spinal deformities, they are far less perform in the wild. Juell et al. (2003) describe that severe than those seen in farmed salmon (Sambraus

Page 24 FISH WELFARE ON SCOTLAND’S SALMON FARMS et al. 2014). Fish with spinal deformities suffer as they are not able to swim effectively, hindering their ability to obtain food and move away from aggressive interactions (Silverstone and Hammell 2002).

Fish Health Inspectorate reports document many incidents of deformities in farmed salmon, including: • At Linga (Setterness), some fish were described as having “stunted growth and deformities” as a result of “a very big tidal flow, in combination with severe weather” which “could have pushed fish against the side of the cages”. (Fish Health Inspectorate, 2016). • At North Voe, the main cause of weekly mortality was noted to be “deformity”. (Fish Health Inspectorate, 2017). • At Lismore North, fish were described as having deformed gill covers (Fish Health Inspectorate, 2016).

Other health defects that farmed salmon experience include abnormal swim-bladders and heart shapes (Poppe et al. 1997, Poppe et al. 2003). Farmed salmon are also often deaf, as a result of deformed sagittal otoliths, an important component of hearing in teleost fish (Reimer et al. 2017). This deformity is likely to be Salmon with a spinal deformity Fish Health Inspectorate caused by genetic selection for fast growth.

Salmon with cataracts Fish Health Inspectorate

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6.3 Stocking density Having too high a density of fish can seriously The weight of salmon stocked in cages of a given size is compromise their welfare in the following ways, known as stocking density. Unfortunately, the Scottish though this is not an exhaustive list: Government does not hold data on stocking densities for salmon farms in Scotland, nor is the collection of 6.3.1 Increased aggression stocking density data done routinely by the Fish Health Having more salmon in a confined space increases the Inspectorate. However, RSPCA Assured standards for prevalence of aggressive interactions, as salmon cannot salmon set a maximum stocking density of 22 kg/m3 express their natural avoidance behaviour. Canon- Jones at seawater farms. Given that 78% of salmon farms in et al. (2011) found that increased stocking densities Scotland are certified under this scheme, in theory most resulted in increased occurrence of dorsal fin damage. sites should not have a stocking density greater than This is likely as a result of an increased prevalence of fin this. This threshold has been set at this level because biting by other salmon. Ashley (2007) argues that high research has found that high stocking densities can stocking densities can cause “chronic social stress”, with compromise fish welfare, and Turnbull et al. (2005) fish that are victim to aggressive interactions suffering found that densities of over 22 kg/m3 caused reduction as a result of decreased feeding, changes in metabolism, in fish welfare. impaired immune function, and reduced growth.

It is important to note that the actual group densities 6.3.2 Increased spread of disease and parasites that farmed salmon experience are likely to be different Increasing the amount of fish within an area creates the to the stocked density. Salmon tend to prefer specific perfect conditions for diseases and parasites to spread environmental conditions, meaning that they will often throughout the population. There is also evidence that group together in certain areas (for example, to avoid intensive farming of fish can cause rapid evolution of areas of low dissolved oxygen concentrations) (Stehfest pathogens, creating bacterial strains that have high et al. 2017). This leads to an increased local density of virulence (ability to cause harm). This makes such fish. Some suggest that, because of this, actual densities pathogens potentially more damaging to farmed fish of fish can be up to five times higher than overall (Sundberg et al. 2016). stocking densities (Oppedal et al. 2011).

Furthermore, stocking density can be increased as a result of net deformation. Northridge et al. (2013) note that net deformation is not uncommon in Scotland. Net deformation can occur when nets are lifted upwards by water currents, reducing the amount of available space within a net.

Page 26 FISH WELFARE ON SCOTLAND’S SALMON FARMS Farmed salmon with physical damage from handling Fish Health Inspectorate

6.3.3 Reduced water quality 6.4 Husbandry Good water quality is critical for good fish welfare. Having more fish within one area increases 6.4.1 Handling the concentrations of waste and decreases the Not surprisingly, handling causes severe stress to fish. concentration of oxygen. There are many factors that Ashley (2007) notes that removal from the water “elicits determine the quality of water, including dissolved a maximal emergency physiological response” in fish, oxygen, ammonia, carbon dioxide and pH. If levels of and should therefore be kept to a minimum. As well as these are changed, it can impact on the well-being of causing high levels of stress, handling can also result in salmon. For example, research has shown that exposure physical damage, for example the removal of scales. to high levels of ammonia can lead to reduced growth in salmon, as well as causing changes in swimming Farmed salmon are handled during processes such as behaviour, and high mortality levels (Kolarevic et al. vaccination, grading (a process to separate fish into 2012, Knoph, 1996). groups according to their size), treatment and transport. In 2017, at the Ardgaddan salmon farm, 1,078 fish 6.3.4 Issues with low stocking densities died following handling during grading (Fish Health It has been suggested that having too low a stocking Inspectorate, 2017). density can compromise salmon welfare. This is because when there are too few salmon within a cage, territories can quickly develop, potentially leading to increased aggression. Indeed, evidence from Adams et al. (2007) shows that fish held at densities of 15 kg-3 had a lower welfare score than those held at 25 kg-3.

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6.4.2 Crowding 6.5 Transportation Crowding is when fish are gathered into one corner of their cage to make handling them easier. It is done 6.5.1 Transportation within Scotland before practises such as treatment, transportation and slaughter. Throughout their lives, farmed salmon will be transported from their freshwater hatcheries to sea During crowding, salmon are exposed to very high pens, and from sea pens to slaughtering facilities (Farm densities, which can seriously compromise their welfare. Animal Welfare Committee, 2014b). Indeed, Skjervold et al. (2001) found that salmon that were crowded to densities of between 200 kg/m-3 and Prior to transportation, salmon are starved to reduce the 500 kg/m-3 had plasma glucose levels 70% higher than amount of waste products and carbon dioxide within pre-crowding levels. Basrur et al. (2010) also found that tanks. Withdrawing food for too long a period can lead salmon parr exposed to crowding had a growth rate that to increased aggression. Jones et al. (2017) found that was reduced by up to 44%. Crowding can also result in salmon that have their food restricted form two groups, aggression, physical damage, and the deterioration of the “initiators” and “receivers” of aggression, leading to water quality (Stevenson, 2007). increased incidence of fin damage.

6.4.3 Vaccination Whilst being transported, salmon are exposed to Vaccination is important as it can prevent serious numerous stressful stimuli, including increased stocking illness. It is done during the freshwater stage of the density, reduction in water quality, unfamiliar noise and salmon lifecycle to protect them from various diseases vibrations, and loading on and off of vehicles. Many once living in seawater. Vaccination is a crucial tool for studies have shown that transport leads to increased the prevention of suffering on salmon farms, but if it stress in salmon, with studies suggesting that cortisol is not done properly it can cause damage to salmon. levels can increase by up to 15 times from resting This happened in 2016 at the Loch Garasdale salmon values (Iversen et al. 1998, Sandodden et al. 2001, farm, where vaccination led to fungal infection and Iversen et al. 2005). Transportation can also cause consequent mortalities of up to 1,000 fish per day physical damage through handling and contact with (Fish Health Inspectorate, 2016). Bjorge et al. (2011) abrasive surfaces. Fish Health Inspectorate reports make also found that vaccination can lead to peritonitis frequent mention of mortalities relating to transport. For (inflammation), which compromised fish as their latency example, 48,620 salmon died following transportation to eat (the amount of time it takes for fish to eat, once in August 2017 as a result of descaling (Fish Health provided with a food source) was increased, which was Inspectorate, 2017). Furthermore, Iversen et al. (2005) coupled with reduced levels of swimming. Further to this, found that many disease outbreaks that occur on Sorum and Damsgard (2004) found that vaccinated fish salmon farms occur within the first month after smolts had a growth rate that was reduced by up to 20%. have been transported to their sea pens.

Page 28 FISH WELFARE ON SCOTLAND’S SALMON FARMS TRANSPORTATION TO DUBAI

In early 2018, the first live export of salmon parr and The journey from Scotland to Dubai took between smolts from Scotland to Dubai took place. twenty and twenty-six hours and included a five-hour journey by road to Glasgow airport and a seven and a Salmon were transported in a specialist transportation half hour flight to Dubai. system known as FishPac, from a hatchery in Scotland to Dubai, where it is thought that they will be grown until Fish Health Inspectorate reports (2018) document they are slaughtered. the problems with such a journey, noting that: “The shipment that went out 80kg/m2 lost a significant amount of fish”.

6.5.2 Transportation outside of Scotland 6.6 Failed smolts As well as transportation within Scotland, the transport Before being ready for life in a seawater environment, of live salmon smolts abroad is not uncommon. salmon parr undergo smoltification, whereby their Destinations have included Spain, France, Switzerland, physiology changes to adapt to the seawater and Dubai. This is done in specialist containers and must environment; at this stage they are known as smolts. be done in compliance with The Welfare of Animals Within salmon farming, lights can manipulate this (Transport)(Scotland) Regulations 2006. process and induce early smoltification. However, not However, as discussed, transportation can cause all salmon become smolts at the same time, meaning damage and stress to farmed salmon, and can cause some are not adapted for seawater when transferred increased mortalities. When salmon are transported and thus soon die (Stradmeyer 1994). For example abroad, they are often exposed to stressful stimuli at the salmon farm Holms Geo reported 7,702 failed for hours. smolts dying in 2016 (Fish Health Inspectorate, 2016).

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Salmon farm iStock phbcz

6.7 Housing provision of shelter actually reduced the growth rate of fish at high densities. Therefore, more research is 6.7.1 Enrichment needed to determine how enrichment could be best Farmed salmon have very little variety in their used to improve farmed salmon welfare. environment, and enrichment is rarely (if ever) provided for them. This is vastly different to their natural, wild 6.7.2 Netting environment where they are exposed to many different Today, most salmon farms use nets made of rubber stimuli, in both freshwater and saltwater environments. and plastic. These surfaces can be abrasive to salmon, Whilst the research into whether enrichment would creating physical damage. Nets can also acquire benefit farmed salmon is minimal, there is some biofouling organisms (such as mussels, algae, and suggestion that it would improve welfare. Brown et al. bacteria), which can affect fish welfare by reducing (2003) found that salmon parr raised within enriched oxygen levels, increasing the amount of waste, and tanks (which contained plants, rocks, and novel objects) reducing the efficacy of cleaner fish (Floerl et al. 2016). were more successful at foraging live prey. Rosengren Washing nets to remove biofouling organisms can also et al. (2017) found that provision of shelter (shredded create problems as it causes the organisms on the nets material) decreased aggression between salmon to become waterborne, which can then become lodged smolts, as well as levels of stress hormones following in the gills of salmon. disturbance. However, the same study found that

Page 30 FISH WELFARE ON SCOTLAND’S SALMON FARMS 6.8 Slaughter The slaughter of farmed salmon in Scotland is thought Whilst this is currently the most humane slaughter to be of a high welfare standard. Most (95%) salmon method available, sometimes it can be carried out are slaughtered by percussion followed by bleeding, incorrectly or goes wrong, causing suffering to the which is the most humane method of slaughtering fish. For example, the first percussive blow may not be (European Commission, 2017). effective. Furthermore, if fish are not properly graded prior to slaughter, the mechanical percussive This method of slaughtering first requires fish to be equipment will not be set to be effective for all fish. held in well-boats in temperatures of between 4oC This leads to mis-stunning of some fish (European and 6oC, which is intended to calm the fish. Slaughter Commission, 2017). via percussion is usually done by a mechanical device, whereby fish are removed from the water and a bolt A small proportion (5%) of salmon in Scotland are driven by air pressure delivers a percussive blow. stunned using electrical stunners. Salmon are stunned Percussive stunning is non-reversible, as it results in out of the water, and as stunning using electricity is not fish dying of cerebral haemorrhage. permanent, they should then be killed using a humane and immediate method such as percussion (European Commission, 2017).

Salmon at market iStock Straitel 7: MARINE WILDLIFE WELFARE IMPACTS

Brown Trout iStock abadonian Seal William Brown

The farming of salmon in Scotland 7.1 Wild salmon and trout does not just compromise the welfare There is much discussion about the impacts that of farmed fish. It also impacts on the salmon farming has on the welfare of wild salmon and welfare of other animals, including brown trout. Escaped farmed salmon can compromise wild salmon and trout, fish caught for the welfare of wild populations through interbreeding salmon food, seals, cetaceans, and (Karlsson et al. 2016). Sea lice can also impact wild fish, crustaceans. and this can cover a wide range, infecting wild salmon and trout, sometimes up to distances greater than 15 km from salmon farms (Salama et al. 2016). This leads to wild salmon and trout experiencing welfare problems such as osmoregulation disruption and changes in behaviour, which can ultimately lead to increased mortality and population declines (Thorstad and Finstad, 2018).

Page 32 FISH WELFARE ON SCOTLAND’S SALMON FARMS 7.2 Fish caught for salmon food Salmon are carnivores, and therefore need to be shot, and that some seals had multiple gunshot wounds. fed a diet with a high protein content, with much of The general assumption by salmon farm operators is this coming from fish meal and fish oils. In Scotland, that shooting a single seal will be effective in reducing between 20 and 25% of food fed to salmon is made predation on the farm (Northridge et al. 2013). up of fish meal and fish oils, with most of this coming from fisheries along the west coast of South America Operators of fish farms can apply for licences to shoot or Northern Europe (Scottish Association for Marine seals. Both grey and common (harbour) seals are shot Science, 2017). This raises concerns for the welfare of on salmon farms in Scotland, in an attempt by salmon fish caught to feed farmed salmon, as it is estimated farm owners to reduce predation. Just under 50 seals that the production of 3.6 kg of farmed salmon will have were shot in 2017 on salmon farms. Although this involved killing tens or hundreds of feed fish (Mood and number is much diminished from previous years (Figure Brooke, 2012). 5) as a result of introduction of a licensing system under

120

100

80

60

40

NUMBER OF SEALS SHOT 20

0

2013 2014 2015 2016 2017

Figure 5. The number of seals shot on salmon farms in Scotland between 2013 and 2017 Source: Marine Scotland Seal Licensing, 2013- 2017

7.3 Seals the Marine (Scotland) Act 2010- shooting still seriously Research by Nunny et al. (2016) on post-mortems of compromises the welfare of those seals that are shot. seals that have been shot highlight the suffering that these seals face. It has been found that seals have been However, this assumption is not supported by scientific shot in the water, a practice that experts say can never evidence, which suggests most seals that associate with be humane because of the prolonged suffering and salmon farms are transient, meaning they will rarely visit increased risk of injury it causes. Further post-mortems a particular farm site more than once (Northridge et al. show that pregnant or lactating mothers have been 2013).

FISH WELFARE ON SCOTLAND’S SALMON FARMS Page 33 7: MARINE WILDLIFE WELFARE IMPACTS

Harbour Porpoise William Brown

7.4 Cetaceans The main way that salmon farms currently impact There are other ways that cetaceans can be impacted cetaceans is through the use of Acoustic Deterrent by salmon farming, for example through entanglement. Devices (ADDs). These devices emit a high frequency In 2014, a humpback whale died off the coast of Mull sound in an attempt to deter seals from salmon farms. from drowning after becoming trapped under a salmon However, there is little evidence that ADDs remain fully pen (Scottish Rural College, 2014). effective over the longer term in reducing seal damage. Seals have been shown to associate with salmon farms 7.5 Crustaceans that use ADDs, and there is even a suggestion that they There is increased understanding and acknowledgement may be attracted to them (Gotz and Janik 2013). that crustaceans are capable of feeling pain and suffering (Elwood and Appel, 2009). Salmon farming There is, however, clear evidence that ADDs can have can harm crustaceans such as lobsters and crabs unintended negative effects on cetaceans, most notably through the use of emamectin benzoate (Slice®), which harbour porpoise which are often resident in the same is a chemical used to treat sea lice that can be toxic to areas as salmon farms (Hebridean Whale Dolphin Trust crustaceans. For example, it has been shown that use 2018). Evidence shows that ADDs can cause disturbance of emamectin benzoate led to reductions in abundance to harbour porpoise through excluding them from and richness of wild crustacea (Scottish Aquaculture sections of their habitat (Johnston 2002). There is also Research Forum, 2016). a suggestion that they can cause hearing damage and alter the behaviour of cetaceans (Lepper et al. 2014).

Page 34 FISH WELFARE ON SCOTLAND’S SALMON FARMS 8: FUTURE CHALLENGES

With targets set for growth, and the 8.2 Moving sites offshore problems identified, there is suggestion Another suggestion is to move sites further offshore as well as relaxing limits on biomass. This is seen by that the salmon farming industry may the industry as a solution to the lack of available space use different methods of farming. The for the development or expansion of salmon farms two most widely discussed currently (Scottish Aquaculture Innovation Centre and Highlands are closed containment systems, and and Islands Enterprise, 2017). movement of salmon farms offshore. Moving sites further offshore would expose the salmon

8.1 Closed containment to harsher sea conditions, which has the potential Closed containment involves creating a complete barrier to increase the severity of the physical damage they to separate the fish from the surrounding water. This experience and could increase mortalities. Furthermore, can be done both on land and in water. Many argue because of harsher sea conditions and increased speed that closed containment is the solution to a lot of the of water flow, it is likely that there will be an increase in environmental and fish health problems associated the distortion of netting, increasing the actual stocking with salmon farming, for example by removing the risk density. of disease and sea lice. However, closed containment systems are a lot more expensive to run than the Furthermore, moving sites further offshore would make seawater pens currently used. To compensate for it harder for the Fish Health Inspectorate and vets to this, it’s likely that greater stocking densities would visit farms, making monitoring of fish welfare and health be used, which could seriously compromise the challenging. welfare of salmon. Furthermore, closed containment systems require water to be continuously moving in Moving sites further offshore risks having a greater one direction. This means that salmon that are ill impact on the welfare of cetaceans. If ADDs are used at cannot rest or remain still as they are pulled by the offshore sites, they are more likely to affect cetaceans water movement, which can cause physical damage because of increased overlap with suitable habitat. and death. Closed containment systems are also completely managed environments, which increases the risk of human error or equipment failure, both of which can be catastrophic. One example of this is that at Kinlochmoidart Hatchery, operated by Sunbeam Aquaculture, where a power cut led to the death of 140,886 (39%) of fish on site in February 2016 (Fish Health Inspectorate, 2016).

FISH WELFARE ON SCOTLAND’S SALMON FARMS Page 35 9: ACCREDITATION SCHEMES AND STANDARDS

Scotland’s salmon farms are accredited The standards set limits on stocking density, starvation by numerous schemes. The most period, and handling, and ban the lethal control of predators. Unlike other organic standards, the use of notable for animal welfare is the chemicals is not prohibited. Instead, there are limits RSPCA’s Assured standards, although on the number of times drug treatments can be used. others include the Code of Good For example, they state that parasite treatments Practice, GlobalG.A.P, Label Rouge and should only be used a maximum of twice a year if the the Soil Association Organic standards. production cycle is 18 months or over. The stocking density recommended under soil association standards 3 9.1 Certification in Scotland is 10 kg/m , a density which may compromise salmon Just under 78% of salmon farms in Scotland are welfare through causing increases in aggression certified by the RSPCA Assured scheme. Just five sites (Adams et al. 2007). As these standards follow EU were certified as organic in 2016, and all sites operated organic regulations, they do not allow for the use of by companies in the Scottish Salmon Producers recirculatory aquaculture systems (RAS), a form of Organisation (all major salmon producers except for closed containment. Grieg Seafood Ltd.) follow guidelines set by the Code of Good Practice (2015). Only five Scottish salmon farms were certified as organic in 2016. To become certified as organic, fish

9.2 What protection do standards farm operators must pay a fee of £624 (or £520 for provide salmon? hatcheries). Inspections are carried out annually. Previous analysis of welfare standards by OneKind and Compassion in World Farming (2012) compared RSPCA, 9.2.2 RSPCA Assured Soil Association and Code of Good Practice standards. RSPCA Assured standards for farmed Atlantic salmon Whilst standards have changed since this report, it gives aim to “represent good practice in the care and welfare a good indication of the level of protection afforded by of commercially-farmed Atlantic salmon at all stages of these schemes. This analysis rated Soil Association as their lives.” (RSPCA, 2018). the best for animal welfare, followed by the RSPCA, and then the Code of Good Practice. The scope of these Standards set by the RSPCA Assured scheme are based three schemes are outlined below. on the principle of the “five freedoms”. The most recent farmed Atlantic salmon standards were published in

9.2.1 Soil Association Organic standards February 2018. They cover the whole life cycle of farmed The aquaculture standards set by the Soil Association salmon, from freshwater to seawater, and ultimately aims to provide the “highest possible standards of slaughter. RSPCA Assured has had some success in animal welfare, environmental and wildlife protection”, improving farmed salmon welfare. A key example of this and follow the EU organic regulations. They are not is that it only permits killing using a percussive blow, limited to salmon, and include a wide range of fish which, if done correctly, is the most humane method of species, crustaceans, echinoderms and molluscs. slaughter (European commission, 2017). Partly because

Page 36 FISH WELFARE ON SCOTLAND’S SALMON FARMS of this, most (95%) salmon farms in Scotland only salmon, and includes farm design and location, sea lice slaughter using this method. and disease control, and husbandry practices such as handling and crowding, and humane slaughter. They However, the RSPCA Assured standards allow lethal also include provisions for cleaner fish, for example they control of seals: “However, at the present time, it is require provision of adequate hides for cleaner fish. acknowledged that in some exceptional cases, and as As the Code of Good Practice (2015) does not a last resort only, and where the welfare of the fish has exclusively cover salmon, some provisions are not as been compromised, i.e. they have been injured/attacked, specific as those under the RSPCA Assured standards. it may be necessary to use a lethal deterrent (i.e. shoot) For example, the Code of Good Practice does not set a a seal to protect the welfare of the fish”. maximum stocking density, but states that: “Stocking density should be monitored in relation to The standards also permit the use of triploid fish, health, fish behaviour and water quality to ensure that despite evidence that they have severely reduced fish welfare is not compromised”. welfare compared to diploids, and the use of cleaner fish, despite the high mortality rates and welfare This is similar to the Code of Good Practice requirements challenges these fish face. for feed withdrawal, handling and crowding, as no limits for these are provided, they should just be kept to a Seventy eight percent of salmon farms in Scotland are “minimum”. certified by RSPCA Assured. Farms that are certified are then checked annually by inspectors. A list of Like the RSPCA Assured standards, the Code of Good farms certified by RSPCA Assured is not currently made Practice allows the lethal control of predators, as long available to the public. as it is done in accordance with legislation. It also recommends the use of ADDs, though does not provide 9.2.3 Code of Good Practice any information on best practice for these. The Code of Good Practice for Finfish Aquaculture in Scotland was introduced in 2006 but reviewed in Whilst the Code of Good Practice contains many 2015 to include the latest industry developments. All welcome references to the welfare of farmed fish, farms operated by companies in the Scottish Salmon many of the provisions are too vague and therefore Producers’ Organisation subscribe to it (all companies are ineffective in safeguarding salmon welfare. The except Grieg Seafood Shetland Ltd.). This means that report on farm assurance schemes by OneKind and 90% of production is done under the Code of Good CIWF (2012) concluded that the Code of Good Practice Practice. standards “offer few welfare benefits compared with standard industry practice”. The Code of Good Practice (2015) aims to bring the standard of salmon farming “up to a specified acceptable level” that is “based on science and experience”. It covers all stages of the life cycle of

FISH WELFARE ON SCOTLAND’S SALMON FARMS Page 37 10: LEGISLATION AND INSPECTION Farmed fish in Scotland are not 10.1 Animal Health and Welfare protected by the wider Welfare of (Scotland) Act 2006 The Animal Health and Welfare (Scotland) Act covers Farmed Animals (Scotland) Regulations “any vertebrate other than man” that is commonly 2010, but they are subject to other domesticated in the British Islands, under the control legislation. of man on a permanent or temporary basis, or not living in a wild state. The Act covers all farmed fish and places a duty of care on those responsible for farmed salmon to safeguard them from unnecessary suffering, promote their welfare and prevent distress. This means that, under the Act, farmed salmon should be provided with a suitable environment, diet, opportunity to express normal behaviour, and protection from diseases, pain, and suffering. In August 2010, following the deaths of 20,000 salmon following chemical poisoning, the regional manager and site manager for the company Hoganess Salmon were charged with animal cruelty. However, they were not prosecuted (Farm Animal Welfare Committee, 2014a).

If the person responsible for the care of animals commits an offence in that they fail to safeguard the welfare, and prevent harm to the animals in their care, they can face up to 12 months in prison, a fine of up to £20,000, or a combination of both.

Page 38 FISH WELFARE ON SCOTLAND’S SALMON FARMS 10.2 The Welfare of Animals (Transport) 10.4 Aquaculture and Fisheries (Scotland) Regulations 2006 (Scotland) Act 2013 These regulations implement EC Regulation No 1/2005 This Act covers various issues such as escapes and regarding the protection of animals during transport. disease spread and promotes good management. The It covers all vertebrates, and therefore includes farmed Act is intended to ensure that aquaculture and fisheries salmon, and protects the welfare of animals throughout are managed effectively. For example, it requires that transportation in connection with an economic activity. all fish farms have a farm management agreement As pointed out by the Farm Animal Welfare Committee that covers fish health, parasites, movement of fish and (2014a), some of the provisions included do not suit the harvesting. It also gives power to inspectors to collect transport of fish, for example that sufficient floor area samples of fish from farms to aid in understanding and height is provided for all animals. The regulations escape events. are enforced by local authorities, with additional checks and monitoring by the Animal and Plant Health Agency, 10.5 Inspections and if found to be guilty of an offence, individuals can Sites are inspected by the Fish Health Inspectorate who face up to three months in prison, or a fine of up to mainly focus on disease management. They are not £5,000, or both. tasked directly with monitoring welfare of farmed fish and can only take action on welfare where it relates 10.3 Aquatic Animal Health (Scotland) to disease. The responsibility for all other welfare Regulations 2009 concerns lies with the Animal and Plant Health Agency These implement EC Directive 2006/88 which relates (APHA). If a welfare issue is detected by the Fish Health to animal health and the prevention and control of Inspectorate they will pass this information on to the certain diseases. Within these regulations there is APHA for follow up. Fish Health Inspectorate reports requirement for the Fish Health Inspectorate to carry do however give insight into welfare issues on farms, out unannouced inspections. including problems with diseases, sea lice, treatment, and mortalities.

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OneKind believes that animal welfare on salmon farms in Scotland needs improving urgently, and that the following recommendations should be introduced as soon as possible.

1

INTRODUCE A MORATORIUM ON THE EXPANSION OF THE INDUSTRY

The salmon farming industry should halt its expansion until it has successfully addressed the current animal welfare challenges

On 25th March 2015, Scotland’s National Marine Plan Doubling production will exacerbate the current welfare (NMP), produced by the Scottish Government, was problems on salmon farms and result in many more fish adopted to ensure “sustainable economic growth of suffering. In addition, we note the compelling evidence marine industries”. The Plan sets specific growth targets that salmon farms place a large and unsustainable for the aquaculture industry of 210,000 tonnes of finfish burden on the natural environment (Environment, (true fish, and not shellfish) by 2020, an estimated 45 Climate Change and Land Reform Committee, 2018). million salmon. OneKind therefore recommends a moratorium on In October 2016, the Aquaculture Growth to 2030 industry growth that applies to the development of plan was published by an industry working group, new farms and the expansion of current ones. This compromised of representatives from the Scottish moratorium should be kept under review, to be lifted Salmon Producers Organisation, Scottish Aquaculture once the industry demonstrably passes three tests: Innovation Centre, Scotland Food and Drink, Association of Scottish Shellfish Growers, Highland Council and 1. The farmed salmon and any cleaner fish have leading businesses that work in the sector. good lives that are worth living.

The working group envisaged that growth of finfish 2. The industry does not cause suffering to wild aquaculture should reach between 350,000 and animals native to Scottish waters, including 400,000 tonnes (an estimated 63 to 72 million seals, cetaceans and wild salmon and trout. individuals) by 2030, double the production of salmon in 2016 (35 million individuals). These growth targets 3. The environmental impact of salmon farms is are supported by the Scottish Government. reduced and can be shown to do no harm

Page 40 FISH WELFARE ON SCOTLAND’S SALMON FARMS 2 3

NO MOVEMENT OF FARMS STOCKING DENSITIES ON FARMS OFFSHORE AND NO USE OF SHOULD BE NO HIGHER THAN 22 KG/M3 CLOSED CONTAINMENT SYSTEMS Salmon stocked at high densities can have The movement of farms offshore or the use of compromised welfare, and stocking density closed containment would have a major and limits should reflect this. detrimental impact on salmon welfare, and their promise detracts from addressing issues on existing farms.

Closed containment (the complete separation of Stocking densities on salmon farms should not be over cages from the outer environment) is often proposed 22 kg/m3, as high densities lead to increased aggression as a solution to the environmental problems of and production of waste, and decreased oxygen salmon farming. However, closed containment is more concentration and water flow. This limit is justified by expensive to run, and to compensate for this salmon will scientific research which highlights that salmon welfare be stocked at higher densities. This compromises the is compromised at higher densities. Research also shows welfare of salmon through increased aggression and that within cages, salmon are not distributed uniformly, waste products and decreases in the concentration of with salmon clustering in areas which meet their oxygen. Closed containment is also highly mechanised, environmental preferences. This can mean that actual meaning that there is greater risk of human error or densities can be up to five times as high as the stocked equipment failure. density. Furthermore, net distortion can also increase stocking density. These two factors therefore need to Another direction that the industry is taking is to move be considered to ensure that individual salmon have farms further offshore in a bid to create new, and bigger adequate room to express normal behaviours. farms. This exposes fish to stronger water currents and more unpredictable weather, which has been shown to There is also suggestion that low stocking densities cause mass mortalities. Moving farms offshore will also (below 15 kg/m3) can compromise salmon welfare make it difficult for Fish Health inspectors and veterinary through leading to territorial behaviour and aggression. professionals to inspect farmed fish. Salmon should therefore not be kept at a density low enough to compromise their welfare, though more research is needed to reach consensus on what this lower limit should be.

FISH WELFARE ON SCOTLAND’S SALMON FARMS Page 41 11: RECOMMENDATIONS

4

INTRODUCE COMPREHENSIVE, WELFARE-LED TRIGGER LEVELS FOR SEA LICE, AND ENFORCE COMPLIANCE

The current approach to sea lice monitoring and treatment fails to account for salmon welfare. Trigger levels should be based on counts of all sea lice and should be enforced effectively.

Currently, there are two sea lice trigger levels that Furthermore, both sets of trigger levels only refer to one guide when action against infestation should be taken life stage of the sea lice: the adult female. This is despite in Scotland. These are those set by the Code of Good the fact that all life stages of sea lice can compromise Practice (2015) and the Scottish Government. The the welfare of farmed salmon. Trigger levels should Code of Good Practice states that treatment against therefore reflect this and cover all life stages of sea lice. sea lice should be taken once average burdens of adult female lice are greater than either 0.5 or 1 per fish, Enforcement of sea lice trigger levels needs to be depending on the time of year. Trigger levels set by the effective. Currently, even when levels of eight adult Scottish Government require that a sea lice action plan female sea lice are exceeded, those responsible face is produced if an average of three adult female sea lice little consequence. This needs to change, and effective per fish is detected. At an average of eight adult female enforcement needs to be routine. sea lice per fish, enforcement action is taken.

Clearly, there are variations in the trigger levels set by the government and the Code of Good Practice (2015). It is not clear why this is the case, nor is there any obvious research that justifies these trigger levels. There is an urgent need for such research.

Page 42 FISH WELFARE ON SCOTLAND’S SALMON FARMS 5 6

INTRODUCE A MANDATORY WELFARE THE USE OF CLEANER FISH SHOULD BE ASSESSMENT BEFORE TREATMENT BANNED UNTIL WELFARE STANDARDS METHODS ARE CONSENTED ARE PRODUCED

The use of new treatments such as Thermolicer The welfare of cleaner fish used in salmon and Hydrogen peroxide for sea lice and disease aquaculture is severely compromised. have been shown to cause severe welfare problems. New treatments should be welfare assessed, and more research should be directed to preventative measures.

Treatment for sea lice and disease is one of the Cleaner fish used on salmon farms suffer from high major causes of mass mortality on salmon farms in mortality rates, aggression, and inappropriate provision Scotland. This needs to stop, and treatments should of supplementary food amongst other issues. Most not compromise the welfare of salmon. For this to will not survive the full production. There is also a lack change, welfare assessment prior to treatment needs of research on cleaner fish behaviour and welfare in to be routine. This should prevent salmon with severely captivity. This is despite the increase in their use, as by compromised health being subjected to further 2020 it is estimated that 10 million cleaner fish will be stressors. The use of new treatments should also not be required by the Scottish salmon farming industry, an done without prior welfare assessment. increase from 380,000 in 2016. Yet there are no welfare standards to guide the use of cleaner fish. There should be a shift in emphasis from the use of treatments to the prevention of initial infection. The use of cleaner fish should be halted until There has been promising research into ways of doing standards that protect their welfare are developed and so, including reducing stocking densities, the use enforced, and until these standards can be shown to be of “snorkel” barriers, and the use of fish behaviour, effective so that cleaner fish are able to live good lives although these require further welfare assessment worth living. (Stien et al. 2016, Bui et al. 2017).

FISH WELFARE ON SCOTLAND’S SALMON FARMS Page 43 11: RECOMMENDATIONS

7 8

THE COLLECTION OF DATA ON ESCAPES ENVIRONMENTAL ENRICHMENT SHOULD NEEDS TO BE IMPROVED, AND THE USE OF BE PROVIDED TO FARMED SALMON TO TRIPLOID FISH SHOULD BE BANNED. REDUCE STRESS

The published information on escape events is Currently, salmon on farms in Scotland live in inadequate to determine the exact cause of the cages with no variety in their environment. escape; and there are concerns about the health This should change, with farmed salmon being and welfare of triploid fish provided with enrichment.

Escapes must be minimised to prevent the suffering of The current conditions that farmed salmon are provided escaped farmed fish as well as wild fish. Whilst data are with do not reflect their natural environment. Salmon available on escape events in Scotland, it needs to be farms offer little variety in environment for fish, with improved. Currently, very little detail can be ascertained little (or no) enrichment provided. This contrasts with and there appears to be overlap between some of the their natural environment, where salmon encounter categories (e.g. human error and inappropriate use of variety in both freshwater and seawater. equipment). More detail on the cause of escapes should be provided to help identify major issues and prevent Environmental enrichment should be provided for them from happening in the future. farmed salmon. This could include structures that mimic seaweed or shelters. Enrichment has the capacity to One solution to the problem of escaped salmon improve the welfare of farmed salmon by, for example, interbreeding with wild fish is the use of triploid reducing aggression and stress levels. As well as being a salmon. These are salmon who have an extra basic ethical requirement, reducing stress is beneficial chromosome, which makes them infertile. This prevents to the industry as fish that are less stressed are less them from interbreeding with wild individuals. OneKind vulnerable to infection from diseases and parasites. does not support the use of triploid fish as research shows that they have increased mortality and reduced welfare compared to diploid (“normal”) salmon. Triploids have been shown to have a greater prevalence of spinal deformities, cataracts, and are more sensitive to temperature stress. They also face increased levels of aggression when compared to diploids. For these reasons, there should be a ban on the use of triploid salmon.

Page 44 FISH WELFARE ON SCOTLAND’S SALMON FARMS 9 10

SALMON SHOULD BE THOUGHT OF THE IMPACT OF SALMON FARMING ON AS INDIVIDUALS, NOT TONNES OTHER ANIMALS NEEDS TO BE REDUCED

Salmon are sentient beings, and considering Salmon farming can seriously compromise the them in terms of tonnes and not as welfare of other wild animals. Urgent efforts are individuals is not acceptable and leads to needed to address this, including an end to the their commoditisation. killing of seals.

The industry, Scottish Government and the public BAN SEAL SHOOTING need to consider salmon as individuals in the same The lethal control of seals should be banned, and way that other farm animals are. One of the ways that alternative deterrents or preventative measures should the commoditisation of salmon is most frequently be used. These include the use of seal blinds and the expressed and reinforced is the reporting of information removal of dead fish, which would otherwise attract relating to salmon in tonnes rather than the number of seals. The use of predator nets should be kept to a individuals. For example, data that is currently available minimum due to the risk they pose to wildlife through on salmon mortalities is only provided in kilograms. entanglement.

Referring to sentient animals in terms of their weight REDUCE THE USE OF ACOUSTIC is unacceptable. We recommend that the industry and DETERRENT DEVICES the Scottish Government always publish data on the There needs to be emphasis on a reduction of the number of individuals as well as their collective weight. use of acoustic deterrent devices (ADDs) on salmon For example, mortality data should include the number farms, with a view to discontinue their use, due to their of individual salmon that died, not just their mass. negative impacts on cetaceans. There should instead be emphasis on alternative, humane measures that successfully deter seals without harming cetaceans.

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