In a 3 minute interview, Professor Elwood of Queens University in Belfast describes his new research and concludes we should therefore find more humane ways of handling and killing these animals: http://www.bbc.co.uk/news/science-environment-21063999.

Professor Elwood’s previous research is discussed here: reports-from-the-ufaw-and-hsa-symposia-portsmouth-july-2011.

Salmon farm, U.S.
Credit: Department of Marine Resources, State of Maine.

and has published welfare guidelines on the transport and slaughter of farmed fish. However, most farmed fish throughout the world, and many in the EU, are handled, transported and killed by methods that do not meet these welfare recommendations and are not humane.

EU law recognises fish as sentient beings and gives theoretical protection during rearing and slaughter. The EU’s “AHAW” panel has published scientific opinions on the animal welfare aspects of husbandry systems for six farmed fish species (Atlantic salmon, trout, eel, common carp, seabass and seabream) and on the welfare aspects of the main systems of stunning and killing of eight farmed fish species (the above species, turbot and tuna). However, EU directives contain no detail regarding fish on permissible rearing conditions, such as stocking density or enrichment, or slaughter methods. Many existing commercial killing methods cause substantial suffering over a prolonged period of time.

The magnitude of the serious welfare problems in EU and global fish farming are multiplied by the large numbers of animals involved. It seems probable that the rising number of farmed fish slaughtered globally for food each year, estimated at between 37 and 120 (midpoint 80) billion^* in 2010 (see estimate of farmed fish numbers), has already have overtaken that of farmed mammals and birds reported by the FAO at 63 billion that year.

In the EU, farmed fish numbers are lower but represent a significant proportion of farmed vertebrates slaughtered each year. EU farmed fish numbers are estimated at 460 to 1,700 million^**, for which the mid-point of 1.1 billion equates to 15% of total EU farmed birds and mammals slaughtered in 2010 (most of these (86%) being chickens). Since the lifespan of farmed fish (typically ranging from a few months to over a year) is generally several times that of broiler chickens reared for meat (which are typically slaughtered at around six weeks of age) the numbers of animals in the EU alive at any one time may well be greater for fish than the combined totals for farmed mammals and birds.

Improving fish welfare in global aquaculture will require:

• humane slaughter, transport and handling methods
• environmental rearing conditions that both promote fish health and meet the ethological needs of the species
• fish feeds based on trimmings and alternative feeds rather than purpose-caught wild fish.

Some key welfare issues in fish farming are discussed in the pages below. A fully referenced discussion of the welfare issues in fish farmed is available in the following paper:
Study to estimate numbers of farmed fish killed in global aquaculture each year ( 540 KB) 40 pages. July 2012.

1. Chapter 7.1. Introduction to recommendations for the welfare of farmed fish. 2010 OIE Aquatic Animal Health Code. http://web.oie.int/eng/normes/fcode/en_chapitre_1.7.1.pdf.

Wild caught fish suffer slow and distressing deaths in enormous numbers.
Credit: National Oceanic and Atmospheric Administration/Department of Commerce.

How big is a problem of animal suffering? This depends on the numbers of animals involved. The total magnitude of animal suffering may be quantified with the equation:

Magnitude of welfare problem

=

Severity

x

Duration

x

Numbers.

For most wild-caught fish, and also most farmed fish, during capture and subsequent processing the severity and duration of suffering will be high. Most wild-caught fish are likely to die from being crushed in nets or from suffocation, freezing or live dissection after landing. This process will probably take many minutes, or even hours. Most of the world’s farmed fish are also killed by slow and inhumane methods.

The following studies estimate the numbers of fish killed globally each year in fishing and fish farming, using FAO fisheries capture and aquaculture production tonnages together with estimated mean weights for fish species. It is estimated that, each year:

• 970 – 2,700 billion fishes are caught from the wild, of which
• 450 – 1,000 billion fishes are caught to make fishmeal and fish oil.
• 37 – 120 billion farmed fish are killed for food.

These huge numbers mean the treatment of fishes in commercial fishing and fish farming are major animal welfare issues.

 
Numbers of fish caught from the wild each year

Japanese jack mackerel (Trachurus japonicus).
An estimated 3.5 to 20 billion individuals of this species are caught each year.
Credit: Nemo's great uncle.

In this study it is estimated that between 0.97 and 2.7 trillion^* fish (ie 970,000,000,000 to 2,700,000,000,000) were caught from the wild globally each year for 1999-2007.

• introduction to the study
• study overview
• full writeup of study (109 KB)
• results on screen
• results in pdf document (216 KB)
• results in spreadsheet (XLS, 1,922 KB)

 
Numbers of farmed fish slaughtered each year

Grass carp (Ctenopharyngodon idellus) in aquarium.
An estimated 1.7 to 8.7 billion farmed individuals of this species are "harvested" for food each year.
Credit: Lebatihem Ehsan.

In this study it is estimated that between 37 and 120 billion^* (ie 37,000,000,000 – 120,000,000,000) farmed fish slaughtered for food globally in 2010.

• introduction to the study
• study overview
• full writeup of study (540 KB)
• results on screen
• results in spreadsheet: global estimated numbers 2010 (XLS, 520 KB)
• results in spreadsheet: estimated numbers by country and year with graphs (zipped XLS, 9.9 MB zipped; 38.4 MB unzipped)

 
Numbers of wild fish caught for reduction to fish oil and fishmeal

The above study to estimate numbers of farmed fish also estimates that, on average each year for 2005-2009, between 0.45 and 1.0 trillion^* (ie 450,000,000,000 – 1,000,000,000,000) wild fish were caught for reduction to fish oil and fishmeal, mainly used to feed farmed fish.

• results on screen
• numbers of fish used for feed in aquaculture

Extracts from this report are now available in French from Les Cahiers antispécistes:

• Le pire a lieu en mer
  Les méthodes de la pêche commerciale
• Combien de poissons sont pêchés par an ?

The summary report is available in a German adaptation by the Swiss fish welfare organisation fair-fish:

• Auf See geht es schlimmer zu:
  Leid und Wohl gefangener Wildfische

If fish could scream

This article by Peter Singer, published on the Project Syndicate website on 13 Sep 2010, discusses animal suffering in commercial fishing and is available in several languages.

Progress towards better welfare at slaughter for wild fish and other marine creatures

Papers and posters etc from these two excellent symposia, held in Portsmouth, UK in July 2011 by the Universities Federation for Animal Welfare and the Humane Slaughter association, included:

• A presentation on research into humane slaughter of fish on fishing vessels using dry electric stunning
• A poster presentation: “Improving Welfare in Commercial Fishing- constraints and opportunities”
• Other poster presentations on the welfare of fish in commercial fishing
• A presentation on the sentiency of decapod crustacea
• A poster presentation: “Humane slaughter of crustaceans”
• Presentations on the welfare of farmed fish
• The 2011 Humane Slaughter Association Award awarded for work in humane slaughter technology for farmed fish.

Presentation: Electrical stunning of captured fish.
See p18 of HSA Speaker Abstracts

This presentation at the HSA conference describes a study on board Norwegian vessels to establish the time taken for cod and haddock to lose consciousness; to test the viability of carrying out humane slaughter at sea and its effect on fishery operations. The research is being prepared for publication.

During an experimental trawl carried out over a 3-4 hour period (rather shorter than the usual commercial trawl), cod and haddock were landed on board. To test the length of consciousness out of water, the team took five fish shortly after landing and another five every half hour until processing was near completion two hours later. These fish were tested for brain and heart function by EEG and ECG respectively and for behavioural signs of awareness.

After two hours of storage out of water, the cod appeared motionless. However, the EEG test showed that all still showed signs of consciousness. This suggests that the welfare benefits of early stunning and humane slaughter are considerable.

The fish were stunned using a dry-stunning system which had been installed on the boat. This is preferred to a wet-stunning system since a higher current is required in salt water, resulting in tissue damage¹. EEG recordings were used to show that a voltage of 52 V_rms at a frequency of 100 Hz for 1 s produces sufficient current to stun cod or haddock. They are then cut and bled to kill them before consciousness returns.

The fish are fed into the dry chamber from a water tank. Recently, equipment has been devised to ensure that fish enter the stunning chamber in not more than one layer of animals. The issue of a sound dosing system² needs further investigation.

The fishermen responded favourably to the system. Stunned fish are easier to handle, reducing the time taken to gut and rinse them.

The same team is also conducting research in the Netherlands with Dutch fishermen who wish to improve welfare. Early research using EEG measurements on the flatfish turbot and sole suggests that these species can be stunned with a voltage of 100 V_rms. Studies on dab have also started and work on plaice is planned.

¹The other alternative method commonly used for farmed marine fish is percussive stunning.

²i.e. to prevent the fish being exposed to pre-shocks. Dosing systems for electrical stunning after dewatering have been developed for farmed species like eel, A. catfish, a hybrid of A. catfish and Vundu catfish and Atlantic salmon.


Poster presentation: Improving welfare in commercial fishing – constraints and opportunities.
See p34 of UFAW Poster Abstracts

This poster presentation, at the UFAW symposium, outlines some examples of fisheries using more humane methods of capture and employing, or experimenting with, humane slaughter methods. Semi-automated percussive stunners for wild fish are currently under development and preliminary results suggest these can provide a marked improvement in quality. It concludes that wild salmon may be one good place to start in developing humane models of fishing since:

• Some salmon fishers are already using humane slaughter methods
• These fish are often handed individually and “carefully”
• It is a high value species
• Consumers often look to wild salmon as a higher welfare alternative to farmed salmon

and that a premium market in better welfare may help bring better practice across the whole industry. Information in this poster is reproduced at: developing-humane-models-of-fishing


Other presentations on the welfare of fish in commercial fishing
See p26 of HSA Poster Abstracts
See p63 of UFAW Poster Abstracts

Poster presentation “Humane capture & slaughter of commercially-caught wild fish – An emerging issue” argues that the welfare of fish in commercial fishing is a major animal welfare issue on account of the severity and duration of suffering caused and the large numbers of animals involved.

This welfare issue is also included in the survey of veterinary surgeons presented in the poster “Prioritising issues in animal welfare: findings from an online survey of veterinary surgeons”.

Presentation: “Do crustaceans experience pain?”
See p9 of HSA Speaker Abstracts

When Professor Elwood was asked this question by Rick Stein he decided to investigate. Vast numbers of these animals are eaten, a fact which he illustrates as follows: if you ate beef every day you might consume 25 individual cattle over a lifetime whereas the same number of individual prawns could be consumed in just a single prawn cocktail.

In his experiments crabs and hermit crabs demonstrated avoidance learning when subjected to electric shocks. Hermit crabs subjected to electric shocks in their shells were more likely to leave their shell if it was a preferred type of shell, indicating some motivational trade-off. Given new shells, shocked hermit crabs investigated the new shell more quickly and entered it more quickly, i.e. were more motivated to find and accept a new shell, and this change lasted 24 hours. In experiments with glass prawns, when acetic acid or sodium hydroxide was applied to the animals’ antenna prolonged rubbing was observed. This behaviour was inhibited when local anaesthetic was applied. These experiments suggest that responses to noxious stimuli by decapod crustaceans are more than reflexes and that a feeling of pain may be involved.


Poster presentation: “Humane slaughter of crustaceans”
See p8 of HSA Poster Abstracts

This poster describes the ethical and humane killing of crabs, lobsters, langoustine and other decapods crustacean by electro-stunning. The problem with crustaceans is how to stun an animal that has an exoskeleton and doesn’t have a central nervous system. The solution is to stun the animal partially immersed in salt water, to create good contact between the belly and the base electrode, while the stun electrode makes contact with the back of the shellfish. A 110AC voltage is applied and a typical stun current of 4-8 A flows through the animal which is rendered unconscious in less than half a second until prolonged application of the current kills it. A current duration of 5s kills lobsters and langoustines while 10s is needed to kill crabs.

Two (“Crustastun”) machines are commercially available for doing this – a countertop stunner for restaurants and retailers and a batch stunner for shellfish processors. Electro-stunning of crustaceans also brings improved eating quality benefits and can prolong shelf-life.


Presentations on the welfare of farmed fish
See p4 and p8 of HSA Speaker Abstracts
See pages 5, 6, 16, 20, 23, 30 and 31 of HSA Poster Abstracts
See p64 of UFAW Poster Abstracts

A wide range of presentations relating to the welfare of farmed fish was also presented.


Presentation of the “2011 Humane Slaughter Association Award”
This award was presented to joint winners for their work in the development of humane slaughter technology for farmed fish:

• Jeff Lines of Silsoe Livestock Systems for his research into electrical methods for humane stunning and killing
• John Ace-Hopkins of Ace Aquatec Limited for taking up this research in the development of commercial humane stunning and killing equipment.

How can humane models of fishing be developed? As discussed below, some artisanal fishers are already using humane methods of slaughter with relatively more humane capture methods, and some research is currently investigating the use of percussive and dry electrical stunning machines which could be used on trawl-caught and other fish. Fishers who are already bleeding the fish may be the most likely to begin to adopt humane slaughter methods since humane stunning would only involve adding another step in a current process. Humane slaughter methods may be easier for artisanal fishers since some are already employing them but, on the other hand, larger fishing operations will have economies of scale with the use of humane slaughter technology.

The fishing methods which appear to have the greatest potential for humane capture include:

• fast hook and line methods where use of live bait fish is avoided
• trapping where traps are retrieved in short intervals
• use of surrounding nets.

Sections 1. to 3. below show some fisheries employing humane slaughter methods. Note that we have not conducted any welfare assessment of them but are simply reporting their use of potentially humane slaughter methods from information given on their websites or by email:

1. Fisheries using manual humane slaughter methods
2. Fisheries using more automated humane slaughter methods
3. Humane slaughter as part of certification
4. Correspondence with MSC-certified fishery companies
5. Costs, benefits, constraints & opportunities

1. Fisheries using manual humane slaughter methods

Trolling for salmon.
Credit: Eric Jordan.

Usan Fisheries percussively despatching a salmon.
Credit: Usan Fisheries^TM.

2. Fisheries using more automated humane slaughter methods

Wild Salmon Direct.
Credit: Wild Salmon Direct on YouTube.

The humane slaughter technology used by Wild Salmon Direct is marketed on quality and efficiency by Seafood Innovations International Group Pty Ltd who wrote:

“Seafood Innovations are also developing simple systems to help stun and bleed fish at the first opportunity after harvest. Preliminary results so far have suggested that this can provide a marked improvement in quality as a motivator for better handling practices. The SI technology is seen as a good potential solution in handling fish from, trawl, seine-net and long-line.”

Recent research into the humane slaughter of trawl-caught fish using electrical dry-stunning was discussed at the Humane Slaughter Association’s Centenary International Symposium (see our reports from the ufaw and hsa symposia portsmouth july 2011).

3. Humane slaughter as part of certification

percussive stunning in the fair-fish certification scheme
Credit: fair-fish

• animal welfare
• sustainability and
• fair trade.

Fishery : Wildcatch^TM salmon
Country : Alaska
Year : 2000
Fishing methods nets
Slaughter method : manual spiking followed by bleeding.

Wildcatch^TM was certified organic in 2000. One of the organic standards that this company addressed was the humane slaughter of the catch. Wildcatch^TM told us:

“It may not seem practical to humanely slaughter net caught salmon. However, I think many could be stunned or pricked just prior to the bleeding process. Those that have taken the steps to bleed and refrigerate would be the best recruits to humanely slaughter as these fishers have already embraced change. Monetary incentives paid for bleeding are approximately $0.05 per lb to fishers plus refrigeration of $0.12 per lb. Quality bonuses are also given by salmon buyer at the end of the season based on their sales in the market for his whole pack.”

One of the primary reasons for their pursuit of the organic label was to have a processing chain of custody that would allow them to make up their own set of standards/rules that each fisher would have to sign off to.

Unfortunately organic certification was not continued due to the inherent difficulty of marketing food from wild fish as organic.

4. Correspondence with MSC-certified fishery companies

Several spokespeople and fishing companies for fisheries certified for sustainability by the Marine Stewardship Council were contacted, including Alsakan’s Own^TM and Wildcatch^TM discussed in the sections above. A fisherman representing a larger fishing company responded:

“We are already struggling hard to compete in the market…because of the general market‟s focus on cheap food …with limited focus on sustainability, working conditions, health/nutrition etc. Since we are large suppliers of fish to the world markets, we are not in a position to market our fish as niche products, and have to direct attention to the mass/large markets… “Economic implications would involve extra worker(s), redesign of fish receiving area of vessel (if possible with respect to area constraints), investment in permissible stunning system (various legal constraints on use of stunning, tranquilizing or similar, and unclear basis for defining what would be considered ‘humane’).”

5. Costs, benefits, constraints & opportunities

Benefits from improving welfare include:

1. Better flesh quality from humane slaughter (if fish are not too stressed before landing)
2. Added welfare quality leading to:
   • welfare premiums
   • new markets
   • better welfare choices for consumers
   • more sustainable jobs in fishing.

Economic costs include:

1. Additional labour required per fish for catching and handling
2. Reduced catch sizes in some cases (e.g. from shorter capture durations)
3. Equipment costs for humane slaughter and fish handling (e.g. pumps) technology
4. Redesign of vessels may be required.

Other constraints include:

1. Humane slaughter and handling technology requires further development for larger fishing operations
2. Lack of recognition of this welfare issue among stakeholders
3. Assurance will be more challenging on fishing vessels.

Opportunities

Fishers for whom quality and ethical seafood is part of the branding appear to be the most likely to seek to improve welfare. Many artisanal fishers may be using methods which could be made more humane relatively easily. One good place to start may be wild salmon since:

• Some salmon fishers are already using humane slaughter methods
• These fish are often handed individually and “carefully”
• It is a high value species
• Consumers often look to wild salmon as a higher welfare alternative to farmed salmon.

A premium market in better welfare may help bring better practice across the whole industry.

In this Edwardian novel the ethics of inhumane treatment of wild-caught fish is raised through the heroine, Anna, who is out fishing with friends. Anna empathises with the mackerel that have been caught, unhooked and left to suffocate in a box and is appalled that a live fish has a piece cut out of it to be used for bait. A process of desensitisation to animal suffering is also shown:

Full text is available here.

Concern for the welfare of fish species, like that for other animals, is not new. Here are some examples of humane attitudes towards fishes and complex invertebrates found in literature and religion:

• Arnold Bennett
• D H Lawrence
• Thomas of Celano
• Tu Fu

Anna of the five towns
Arnold Bennett (1867 – 1931)
In this Edwardian novel the ethics of inhumane treatment of wild-caught fish is raised through the heroine, Anna, who is out fishing with friends more…

First life of St Francis, cc. 61, 77
Thomas of Celano (c 1200 – c 1265)
This earliest biography of Saint Francis, based on the testimony of Francis’ close companions, describes his fatherly affection not only towards people but also towards dumb and wild animals including fish. It tells a story in which Saint Francis takes pity on a captured fish and returns him to the lake more…

Hsin yeh-fe shih
Tu Fu (712 – 770)

“I see shining fish struggling within tight nets, while I hear orioles singing carefree tunes. Even trivial creatures know the difference between freedom and bondage. Sympathy and compassion should be but natural to the human heart.”

Taken from The Extended Circle, ed. Jon Wynne-Tyson 1985 1st edition.

Sea and Sardinia
D H Lawrence (1885 – 1930)

“An inkpot…is a polyp, a little octopus which, alas, frequents the Mediterranean and squirts ink if offended…Alessandro caught inkpots: and like this. He tied up a female by a string…through a convenient hole in her end…When Alessandro went a-fishing, he towed her, like a poodle, behind. And thus, like a poodly-bitch, she attracted hangers-on in the briny seas. And these poor polyp inamorati were the victims. They were lifted as prey aboard, where I looked with horror on their grey, translucent tentacles and large, cold, stony eyes. The she-polyp was towed behind again. But after a few days she died. And I think, even for creatures so awful-looking, this method is indescribably base, and shows how much lower than an octopus even is lordly man.”

Taken from The Extended Circle, ed. Jon Wynne-Tyson 1985 1st edition.