fishcount.org.uk https://fishcount.org.uk towards more humane commercial fishing Fri, 24 Jul 2026 17:35:15 +0000 en-US hourly 1 http://wordpress.org/?v=3.5.1 Numbers of other farmed invertebrates https://fishcount.org.uk/fish-count-estimates-2/numbers-of-other-farmed-invertebrates https://fishcount.org.uk/fish-count-estimates-2/numbers-of-other-farmed-invertebrates#comments Fri, 24 Jul 2026 17:29:11 +0000 admin https://fishcount.org.uk/?page_id=17156

 
Table 1. Estimated numbers of farmed aquatic invertebrates besides crustaceans and molluscs (2024).

Taxonomic group Production
(1,000 t)1		 Estimated numbers (millions)2
(Lower) (Upper) (Midpoint)
Sea cucumbers (Holothuroidea) 334 2,100 4,800 3,400
Miscellaneous invertebrates 190 970 2,200 1,600
Sea squirts (Ascidiacea) 23 76 330 200
Sea urchins (Echinoidea) 10 90 90 90
Bristle worms (Polychaeta) 0.5 38 40 39
True jellyfish (Scyphozoa) 83 12 55 34
Total of above 641 3,300 7,500 5,400
1. Source: FAO (2026).
2. Rounded to two significant figures. Full results & notes are available here.

 
We estimated the numbers of farmed aquatic invertebrate animals ‘harvested’ (killed for use as food and feed etc.) in 2024 (Table 1), in addition to the crustaceans and molluscs previously estimated, using FAO aquaculture production tonnages (FAO 2026) and our estimated mean weights. These comprise all other invertebrates not recorded as being crustaceans or molluscs, and their estimated numbers totalled 3.3-7.5 billion individuals (midpoint 5.4 billion or 5.4 * 109 individuals). This includes 0.97-2.2 billion unnamed invertebrates, which may include molluscs and crustaceans. Details of the estimate are available by species and by country.

The largest taxonomic order represented is Echinodermata, comprising an estimated 2,100-4,800 million (midpoint 3,400 million) sea cucumbers (Holothuroidea) and an estimated 90 million sea urchins (Echinoidea).

Sea squirts (Ascidiacea) were the next largest group, with an estimated 76-330 million (midpoint 200 million) individuals. There were also 39 million bristle worms (Polychaeta) and 34 million jellyfishes (Scyphozoa), by estimate midpoint.

Note that these estimates exclude animals caught from the wild (and so exclude sea ranching) and on-farm mortalities. For example, a study of different farming systems for Japanese sea cucumber (Apostichopus japonicus) (discussed below), in a region of China, reported mortalities of 20% for indoor tanks and 10% for semi-intensive ponds during grow out (Wang et al. 2015). Another example of on-farm mortality is the unwanted growth of sea squirts that are discarded at sea (Gao et al. 2023).

Global production of these invertebrates, totalling 641 thousand tonnes in 2024, represented a 22% increase from 525 thousand tonnes in 2020 (FAO 2026).


Sentience, natural behaviours and animal welfare implications

We briefly consider the animal welfare implications of farming these several billion other invertebrate aquatic animals, firstly by looking at the question of sentience. Invertebrate animals are not generally recognised as sentient beings, in law or voluntary codes, but this is beginning to change in some cases.

 
Invertebrate sentience

Birch et al. (2021) developed a framework to evaluate the existing evidence on pain in cephalopod molluscs and decapod crustaceans, and to inform animal welfare legislation. This framework used eight criteria for assessing evidence relevant to pain in animals:

  1. possession of nociceptors;
  2. possession of integrative brain regions;
  3. connections between nociceptors and integrative brain regions;
  4. responses affected by potential local anaesthetics or analgesics;
  5. motivational trade-offs that show a balancing of threat against opportunity for reward;
  6. flexible self-protective behaviours in response to injury and threat;
  7. associative learning that goes beyond habituation and sensitisation;
  8. behaviour that shows the animal values local anaesthetics or analgesics when injured.

Each criterion adds to the case for pain: the more criteria fulfilled, the higher the likelihood. Based on an assessment of evidence against these criteria, Birch et al. (2021) recommended that all cephalopod molluscs (e.g. octopuses) and decapod crustaceans should be regarded as sentient animals for the purposes of UK animal welfare law.

Adopting this framework, researchers have concluded that at least some insects might also feel pain (Crump et al. 2023). Importantly, sentience (i.e. the capacity of an animal to have feelings that matter to them) is not just about pain, and there are ways to make a case for insect sentience that do not proceed via responses to noxious stimuli (Birch 2024). Huge numbers of insects, totalling over a trillion, are farmed for food and feed each year (Barrett & Fischer 2023).

Regarding the sentiency of echinoderms, sea squirts, polychaete worms or jellyfishes, there appears to be less published research (Lewbart & Zachariah 2023). While two of the framework criteria (4 and 8) require a suitable analgesic or local anaesthetic, there is little information on these for invertebrates (Wahltinez et al. 2022), though MS-222 and propylene phenoxetol have been used as local anaesthetics in studies involving echinoderm connective tissue (Crespi-Abril and Rubliar 2023). Information is also lacking on the effectiveness of general anaesthetics recommended for the euthanasia (e.g. in science) of echinoderms, jellyfish and polychaete worms (Bakker et al. 2026) and sea squirts (Bay-Nouailhat & Bay-Nouailhat 2015). However, Carter et al. (2024) formally tested the efficacy of four common anaesthetics, using behavioural and other biomarkers, in northern sea cucumber (Cucumaria frondosa) (see next section). Carter et al. (2024) found that MS-222 seemed to be an effective general anaesthetic, i.e. one that blocks pain rather than just immobilising the animal, representing a promising anaesthetic and sedative in echinoderms and other soft-bodied aquatic invertebrates.

It is critical to recognize that the absence of evidence of painful sensations in echinoderms should not be interpreted as conclusive proof of pain absence in this group, according to Argentinian scientists Crespi-Abril and Rubliar (2023), who argue that echinoderm animals should be treated with respect and compassion in science and farming, without waiting for conclusive evidence of sentience. There are inherent difficulties in determining what an animal is capable of feeling, due to our limited understanding of phenomenal consciousness (Browning & Birch 2022).

We discuss these fascinating animals in the sections below, based on literature searches relating to their natural behaviours, nervous systems and learning:

followed by a conclusion.

 
Echinoderms (sea cucumbers and sea urchins)

The top farmed echinoderm species is the Japanese Sea cucumber, which is farmed for food and medicine (Yang et al. 2015), almost entirely in China, with some production in Russia. Sea urchins (Strongylocentrotus spp) are also farmed in these two countries, mainly for their edible roe (gonads), with some Russian sea urchin production used for pharmaceuticals (Rubilar & Cardozo 2021).

Japanese Sea cucumber is a marine bottom-dwelling species whose natural behaviours include crawling (Hu et al. 2021, Kwon et al. 2019) and foraging, using tentacles surrounding the mouth to collect food (Hu et al. 2021); sheltering (Kwon et al. 2019, Li et al. 2026) and aggregating (Hu et al. 2021, Li et al. 2026).

Sea cucumbers and sea urchins move using their numerous tube feet (Lewbart & Zachariah 2023), tiny tube-like projections on their undersides. Some limited research has suggested that the tube feet, tentacles, and papilla (small, soft projections found on the skin surface) of Japanese sea cucumber may be the most important potential sensory organs for light, chemical and mechanical stimulation (Wang et al. 2023).

A study by Hamel et al. (2021) showed that, upon detecting predator scents, the northern sea cucumber prepares itself for potential injury by rapidly increasing levels of coelomocytes (immune cells) and cortisol, suggesting an internal state that might involve anxiety. Carter et al. (2024) found that MS-222 appeared to be an effective anaesthetic in this sea cucumber species, mirroring its prior use in fish. It completely immobilized the individuals and kept cortisol levels low, even during exposure to a predator starfish (Solaster endeca).

The echinoderm nervous system is organized in a central nerve ring and radial nerve cords, along with peripheral nerves (Paganos et al. 2025). The nervous system lacks a ‘brain’, in the sense of any centrally cephalized group of neurons (Freas & Cheng 2022).

When Paganos et al. (2025) reconstructed the cell atlas of a juvenile sea urchin (Paracentrotus lividus) using single-nucleus transcriptomics, more than half of the cell type clusters were neuronal. The large number of neuronal cell type families identified (totalling 29), together with the high diversity of their molecular signatures and use of diverse neuropeptides, suggested a high functional specialization (Paganos et al. 2025). According to these authors, their analysis strongly supports the hypothesis that echinoderms have a ‘head-like’ body-plan, previously proposed by Formery et al. (2023). Paganos et al. (2025) further concluded that the expression of several vertebrate CNS homologs in tissues throughout the sea urchin nervous system, demonstrated by their study, suggests the nervous system has an ‘all-brain’ organization, which may apply to the entire echinoderm clade. In other words, rather than being brainless, the brain is distributed across the entire organism.

There has been some research into echinoderm associative learning, mainly focused on starfish (Asteroidea), according to Freas and Cheng (2022). For example, when given the choice between a rough or a smooth surface to settle on, starfish and brittle stars (Ophiuroidea) prefer a rough texture, but Diebschlag (1938; cited in Freas & Cheng 2022) trained these echinoderms to reverse this behaviour by giving an electric shock to arms that touched the rough surface. Trained starfish and brittle stars would withdraw their arm as soon as it touched the rough texture, i.e. before a shock was applied, including arms that had not previously been shocked, leading Diebschlag (1938; cited in Freas & Cheng 2022) to conclude that the animal as a whole learned, not individual arms. A more systematic reporting of all animals and all phases of experiments would have enhanced the presentation of this 1938 study (Freas & Cheng 2022).

 
Sea squirts

Red oyas (Halocynthia roretzi) is a solitary sea squirt farmed in South Korea and Japan, for food and bioactive compounds in the tissues (Lee et al. 2020). Some farmed production of unnamed species of sea squirts (‘Ascidiaceans NEI’) is also reported for the former.

Sea squirts, together with other tunicates, are the closest living relatives of vertebrates (Sasakura 2026); tunicates and vertebrates being the two sister groups in the clade Olfactores, within the phylum Chordata.

In their tadpole larval stage, sea squirts possess a central nervous system which is homologous to that of vertebrates, though with smaller numbers of cells (Sasakura et al. 2012). Once the swimming larvae find a suitable settlement location, they attach themselves to the substrate and undergo metamorphosis, to become sessile adults.

Adults are barrel-like and furnished with two chimney-like siphons (inhalant and exhalant) for water circulation inside the body, on which both respiration and feeding relay (Manni et al. 2025). The adult CNS is reorganised, as well as the body plan, as it no longer needs to regulate swimming but now needs to regulate adult organs such as the heart (Sasakura et al. 2012).

Despite it often being said that the metamorphosing tadpole larva ‘eats its own brain’, based on the notion that the adult brain is degraded, adult ascidians have perfectly good brains (Mackie & Burighel 2005). The adult brains (cerebral ganglia) are an order of magnitude larger than those of their larvae, and their behaviour is as finely adapted to sessility as that of the larvae to motility (Mackie & Burighel 2005).

Sea squirt adults possess primary sensory cells that are sensitive to water movement, vibration, and direct tactile contact (Varello et al. 2023). Their stimulation can evoke the squirt response, a strong, synchronous contraction of both siphons that causes a violent ejection of water from them (Varello et al. 2023). Secondary sensory cells located on the oral tentacles, which comprise the coronal organ, are considered homologues of the hair cells of the vertebrate internal ear and lateral line system (Varello et al. 2023). These, like hair cells, allow hearing and vibrational sensing (Varello et al. 2023).

Tolstenkov et al. (2025) found that the sessile adults of the sea squirt species Ciona intestinalis can exhibit different behavioural states, distinguished from each other by various postural and motion features, which can be induced by external stimuli or spontaneously.

Little research exists on learning and memory in adult solitary ascidians (Gasbo et al. 2025). While Gasbo et al. (2025) recently found non-associative learning (sensitisation and habituation) in these animals, this type of learning does not meet the Birch et al. (2021) criteria (see above). Specifically, Gasbo et al. (2025) showed that the solitary sea squirt Polycarpa mytiligera exhibits non-associative learning; its siphon contraction habituated to a weak mechanical stimulus (brush bristles), and this memory lasted for at least one day.

 
Bristle worms

King ragworm (Alitta virens or Nereis virens) and blow lugworm (Arenicola marina) are the two species of bristle worms reported in FAO aquaculture production statistics for 2024, reared in the Netherlands and France respectively. Polychaete worms are presently cultivated in both Europe and Asia, on a relatively small scale, and mainly sold as aquaculture feed or fishing bait, often as live animals (Standal et al. 2024).

Wild king ragworm is omnivorous and found in intertidal mud flats and sand beaches (Du Clos et al. 2013). It builds U-shaped burrows, often 30 cm or deeper, that it expands over the course of a few days and maintains for its semi-sessile lifestyle, generally remaining in its burrow at high tide and emerging at low tide to scavenge for food (Du Clos et al. 2013). King ragworm will burrow under the sand in the direction of food, in order to reach food without leaving the burrow (Copeland & Wieman 1924). Wild blow lugworm lives in 20 to 40 cm deep J-shaped burrows in lower shore sediment, and feeds by swallowing sediment (Riisgard & Banta 1998).

Wild king ragworm defends its burrow from conspecifics, resulting in the expulsion of the intruder or resident, or in cohabitation (Miron et al. 1992). Clark (1959) observed that a closely related species, Nereis pelagica, seemed capable of distinguishing individuals with which it had previously fought. A further observation was that, on one occasion, such a worm anticipated its invasion of a tube (artificial burrow) by fighting a neighbouring worm outside the tube (Clark 1959).

Polychaetes have a brain or cerebral ganglion that originates and usually resides in the head (Verdonschot 2015). There are six major kinds of sensory structures found in polychaetes, which include palps, antennae and eyes (Verdonschot 2015).

King ragworm is able to learn to avoid one arm of a ‘T’ maze in which they receive a slight electric shock, providing ‘correct’ choices (i.e. the arm in which they receive no shock) are reinforced by permitting the worms to remain undisturbed in a darkened chamber for at least 5 minutes before the next trial (Evans 1963). In this study (Evans 1963), the arbitrary learning criterion of 10 consecutive correct choices was achieved after an average of 68.2 maze trials. A period of 48 hours separated the first and last trials in a series of 30 consecutive ‘correct’ choices by one individual king ragworm. During initial training, and once trained, the worms moved rapidly through the maze, but during the later part of training they tended to crawl very slowly and often paused at the junction. Frequently, a worm with some experience in the maze made an ‘incorrect’ choice at the junction, halted before reaching the electrodes, retreated and then continued along the ‘correct’ arm.

 
Jellyfishes

One species of jellyfish, the flame jellyfish (Rhopilema esculentum), was reported in FAO aquaculture production statistics for 2024, which a scyphozoan or ‘true jellyfish’. This species is reared in China, where it is a popular food and also used in traditional medicine, with other potential uses for farmed jellyfish including feed (Duarte et al. 2022). Cultured Rhopilema esculentum is fed on wild zooplankton and brine shrimp (Artemia) nauplii (Duarte et al. 2022).

Jellyfishes belong to the phylum Cnidaria, which is the sister group of Bilateria (Zapata et al. 2015), and are therefore our more distant relatives compared to bilaterian animals discussed here (sea squirts, echinoderms and polychaete worms).

While jellyfishes lack a single centralized brain, it is a common misunderstanding that they have only a diffuse, homogenous nerve net for a nervous system (Katsuki & Greenspan 2013). In most jellyfish, an argument can be made for the presence of centralized nervous systems that interact with the more diffuse nerve nets (Satterlie 2011). Katsuki and Greenspan (2013) describe three main components of the ‘true jellyfish’ (Scyphozoa) nervous system, briefly summarised as follows:

  • the rhopalia, sensory structures located round the bell margin (numbering eight or more, and representing integrative centres for sensory inputs and motor outputs (Satterlie 2011));
  • the motor nerve net, which activates swimming muscles (in response to signals from pacemaker neurones in the rhopalia) and
  • the diffuse nerve net, believed to relay sensory info. to the musculature (both directly (i.e peripherally) and indirectly via the pacemakers).

In a paper whose title begins ‘What’s on the mind of a jellyfish?’, Albert (2011) described what he calls the ‘central nervous system’ of the moon jellyfish genus Aurelia (also Scyphozoan) as a functionally effective brain that deals with sensory input from several modalities (e.g. light, touch, gravity, chemicals, sound pressure waves, direction) simultaneously, generating complex behaviours (e.g. horizontal directional swimming, staying below turbulence and away from rock walls, aggregating) that are not simple reflexes.

A review by Cheng (2021) found no published studies on learning in jellyfish, besides habituation. More recently, Bielecki et al. (2023) showed that a jellyfish in the class Cubozoa (box jellyfish), namely Tripedalia Cystophora, is capable of associative learning that changed its behaviour. Unlike Scyphozoans, Cubozoans possess image-forming eyes, and they have a higher degree of neuronal condensation (Katsuki & Greenspan 2013). This learning process was localised within the rhopalia (Bielecki et al. 2023).

 
Conclusion

Cultivation of these invertebrate species has the important advantage, compared with some fed aquaculture species, that they do not require (inhumanely caught) wild finfishes as feed. Red oyas are farmed in Korea on suspended ropes (Goa et al. 2023) and obtain food by filtering seawater. However, while natural food supply (such as microalgae) is often sufficient for growing Japanese sea cucumber, artificial feed containing fish powder is sometimes used in farms with high stocking densities (Yang et al. 2015).

For better welfare in aquaculture, farming conditions should promote animal health and permit natural behaviours, while minimising stress (including during rearing, breeding and slaughter). Meeting these behavioural needs should be easier for sessile and slow moving animals, like sea squirts and sea cucumbers, than it is for motile finfishes (Jacquet 2017), which is another advantage for animal welfare.

However, methods of killing for food, such as live gutting followed by boiling for sea cucumbers (Yang et al. 2015) and using live ragworms to bait fishing hooks (Morris-Webb et al. 2025) could cause considerable suffering if these animals are sentient.

For the ethical treatment of millions, and in some cases billions of animals, the sentience and welfare needs of all farmed animals should be scientifically investigated. This should include the development of more humane methods of slaughter.

Invertebrates currently farmed in the EU27 (besides insects) include molluscs, decapods and bristle worms; while sea cucumbers are under consideration for future culture (AAC 2024). The Aquaculture Advisory Council (AAC) has argued for the EU to organize a programme of research into the potential sentiency of all farmed aquatic animals (AAC 2024).

 

A. Mood, July 2026.

___________________________________________________________________________

 References

AAC (Aquaculture Advisory Council) 2024 Recommendation on Molluscan Welfare. AAC 2025-1.
https://aac-europe.org/wp-content/uploads/2024/11/1-AAC-Recommendation-on-Molluscan-Welfare.pdf.

Albert D J, 2011. What’s on the mind of a jellyfish? A review of behavioural observations on Aurelia sp. jellyfish. Neuroscience & Biobehavioral Reviews, 35(3), pp.474-482. https://doi.org/10.1016/j.neubiorev.2010.06.001.

Bakker J, de la Garza M A, Morel M, Outwater A H, Chipangura J, Stumpel J B, Vercammen F, Lewbart G A and Nederlof R A, 2026. Euthanasia Methods in Invertebrates: A Critical Narrative Review of Methodological and Welfare Standards. Animals: an Open Access Journal from MDPI, 16(2), p.222. https://doi.org/10.3390/ani16020222.

Barrett M and Fischer B, 2023. Challenges in farmed insect welfare: Beyond the question of sentience. Animal Welfare, 32, p.e4. https://doi.org/10.1017/awf.2022.5.

Bay-Nouailhat W and Bay-Nouailhat A, 2015. Eugenol, another way to anaesthetize ascidians. Association Mer et littoral, Melgven, France. https://www.mer-littoral.org/eugenol-ascidians-anaesthetic.pdf.

Bielecki J, Nielsen S K D, Nachman G and Garm A, 2023. Associative learning in the box jellyfish Tripedalia cystophora. Current Biology, 33(19), pp.4150-4159. https://doi.org/10.1016/j.cub.2023.08.056.

Birch J, 2024. The edge of sentience: risk and precaution in humans, other animals, and AI. Oxford University Press. https://researchonline.lse.ac.uk/id/eprint/126246/1/9780192697684_web.pdf.

Birch J, Burn C, Schnell A, Browning H and Crump A, 2021. Review of the evidence of sentience in cephalopod molluscs and decapod crustaceans. LSE Consulting. LSE Enterprise Ltd. The London School of Economics and Political Science. https://www.lse.ac.uk/News/News-Assets/PDFs/2021/Sentience-in-Cephalopod-Molluscs-and-Decapod-Crustaceans-Final-Report-November-2021.pdf.

Browning H and Birch J, 2022. Animal sentience. Philosophy compass, 17(5), p.e12822. https://doi.org/10.1111/phc3.12822.

Carter J, Jobson S, Hamel J F and Mercier A, 2024. Efficacy of anesthetics in an echinoderm based on multifaceted stress biomarkers. Scientific Reports, 14(1), p.26619. https://doi.org/10.1038/s41598-024-77627-9.

Cheng K, 2021. Learning in Cnidaria: A systematic review. Learning & Behavior, 49(2), pp.175-189. https://doi.org/10.3758/s13420-020-00452-3.

Clark R B, 1959. The tubicolous habit and the fighting reactions of the polychaete Nereis pelagica. Animal Behaviour, 7(1-2), pp.85-90. https://doi.org/10.1016/0003-3472(59)90036-3.

Copeland M and Wieman H L 1924. The chemical sense and feeding behavior of Nereis virens. Sars. The Biological Bulletin, 47(4), pp.231-238. https://doi.org/10.2307/1536502.

Crespi-Abril A C and Rubilar T, 2023. Ethical considerations for echinoderms: New initiatives in welfare. Animals, 13(21), p.3377. https ://doi.org/10.3390/ani13213377.

Crump A, Gibbons M, Barrett M, Birch J and Chittka L, 2023. Is it time for insect researchers to consider their subjects’ welfare?. PLoS Biology, 21(6), p.e3002138. https://doi.org/10.1371/journal.pbio.3002138

Diebschlag E, 1938. Ganzheitliches verhalten und lernen bei echinodermen. Zeitschrift für vergleichende Physiologie, 25(4), pp.612-654.

Duarte I M, Marques S C, Leandro S M and Calado R, 2022. An overview of jellyfish aquaculture: for food, feed, pharma and fun. Reviews in Aquaculture, 14(1), pp.265-287. https://doi.org/10.1111/raq.12597

Du Clos K T, Lindsay S M and Jumars P A, 2013. Spatial distribution of Alitta virens and Clymenella torquata with respect to rigid boundaries in mud and sand. https://www.researchgate.net/publication/261180483_Spatial_distribution_of_Alitta_virens_and_Clymenella_torquata_with_respect_to_rigid_boundaries_in_mud_and_sand

Evans S M, 1963. Behaviour of the polychaete Nereis in T-mazes. Animal Behaviour, 11(2), pp.379-392. https://doi.org/10.1016/S0003-3472(63)80129-3.

FAO (Food and Agriculture Organization of the United Nations) 2026. FishstatJ: Global aquaculture production 1950-2024.https://fao.org/fishery/en/statistics/software/fishstatj

Formery L, Peluso P, Kohnle I, Malnick J, Thompson J R, Pitel M, Uhlinger K R, Rokhsar D S, Rank D R and Lowe C J, 2023. Molecular evidence of anteroposterior patterning in adult echinoderms. Nature, 623(7987), pp.555-561. https://doi.org/10.1101/2023.02.05.527185

Freas C A and Cheng K, 2022. Neuroecology beyond the brain: learning in Echinodermata. Learning & Behavior, 50(1), pp.20-36. https://doi.org/10.3758/s13420-021-00492-3.

Gabso B, Zer-Eshel G, Cohen S, Khayat A, Glanzman D L, Yovel Y and Shenkar N, 2026. Habituation and sensitization learning in adult solitary ascidians. Scientific Reports. https://doi.org/10.1038/s41598-026-43408-9.

Gao P, Khong H Y, Mao W, Chen X, Bao L, Wen X and Xu Y, 2023. Tunicates as sources of high-quality nutrients and bioactive compounds for food/feed and pharmaceutical applications: A review. Foods, 12(19), p.3684. https://doi.org/10.3390/foods12193684

Hamel J F, Jobson S, Caulier G and Mercier A, 2021. Evidence of anticipatory immune and hormonal responses to predation risk in an echinoderm. Scientific Reports, 11(1), p.10691. https://doi.org/10.1038/s41598-021-89805-0

Hu F, Ding P, Yu Y, Wen B, Cui Z, Yang M, Chi X, Sun J, Luo J, Sun Z and Zuo R, 2021. Effects of artificial reefs on selectivity and behaviors of the sea cucumber Apostichopus japonicas: New insights into the pond culture. Aquaculture Reports, 21, p.100842. https://doi.org/10.1016/j.aqrep.2021.100842

Jacquet J, 2017. Seafood in the future: Bivalves are better. The Solutions Journal 8(1) pp 27-32. https://scholarship.miami.edu/esploro/outputs/journalArticle/Seafood-in-the-future-Bivalves-are/991031799419902976/filesAndLinks?index=0.

Katsuki T and Greenspan R J, 2013. Jellyfish nervous systems. Current Biology, 23(14), pp.R592-R594. https://www.cell.com/current-biology/fulltext/S09609822(13)00359-X

Kwon I, Lee K and Kim T, 2019. Shelter material and shape preferences of the sea cucumber, Apostichopus japonicus. Aquaculture, 508, pp.206-213. https://doi.org/10.1016/j.aquaculture.2019.05.011

Lee Y J, Wilberg M J, Han E, Choi K S, Lee W C and Kang C K, 2020. Growth of the longline-cultured sea squirt Halocynthia roretzi in a temperate bay of Korea: Biochemical composition and physiological energetics. Aquaculture, 516, p.734526. https://doi.org/10.1016/j.aquaculture.2019.734526

Lewbart G A and Zachariah T T, 2023. Aquatic and terrestrial invertebrate welfare. Animals, 13(21), p.3375. https://doi.org/10.3390/ani13213375

Li X, Wang S, Song Q, Zhao Z, Sun Y, Ding J and Zhao C, 2026. The characteristics of sheltering behavior in the sea cucumber Apostichopus japonicus. Aquaculture Reports, 46, p.103355. https://doi.org/10.1016/j.aqrep.2025.103355

Mackie G O and Burighel P, 2005. The nervous system in adult tunicates: current research directions. Canadian Journal of Zoology, 83(1), pp.151-183. https://doi.org/10.1139/z04-177

Manni L, Sabbadin G, Domenichi S, Ballarin L, Zaffaroni-Caorsi V and Zambon G, 2025. New Methods for Studying Underwater Noise Effects on Microscopic Sessile Marine Invertebrates: Challenges and Perspectives. In Proceedings of Forum Acusticum-Euronoise 2025 (pp. 6117-6124). https://node.unimi.it/wp-content/uploads/sites/158/2025/07/Manni_et_al_2025-03-28-2.pdf

Miron G, Desrosiers G and Retier C, 1992. Organization of fighting in the polychaete Nereis virens (Sars) and the effects of residency and orientation. Behaviour, 121(1-2), pp.20-34. https://doi.org/10.1163/156853992X00426

Morris-Webb L, Parry R and Jenkins S, 2025. An Evaluation of the Current Use of Farmed vs Wild-Caught Ragworm Bait in Wales: NRW Evidence Report No: 883. https://research.bangor.ac.uk/en/publications/an-evaluation-of-the-current-use-of-farmed-vs-wild-caught-ragworm/

Paganos P, Ullrich-Lüter J, Almazán A, Voronov D, Carl J, Zakrzewski A C, Zemann B, Rusciano M L, Sancerni T, Schauer M and Akar O, 2025. Single-nucleus profiling highlights the all-brain echinoderm nervous system. Science Advances, 11(45), p.eadx7753. https ://doi.org/10.1126/sciadv.adx7753

Riisgard H U and Banta G T, 1998. Irrigation and deposit feeding by the lugworm Arenicola marina, characteristics and secondary effects on the environment. A review of current knowledge. Vie et Milieu/Life & Environment, pp.243-257. https://hal.sorbonne-universite.fr/hal-03173003/document

Rubilar T and Cardozo D, 2021. Blue growth: sea urchin sustainable aquaculture, innovative approaches. Revista de Biología Tropical, 69, pp.474-486. https://hal.sorbonne-universite.fr/hal-03173003/document

Sasakura Y, 2026. Thaliacean tunicates, vertebrate sisters regained lifelong mobility. Plos Biology, 24(3), p.e3003674. https://doi.org/10.1371/journal.pbio.3003674

Sasakura Y, Mita K, Ogura Y and Horie T, 2012. Ascidians as excellent chordate models for studying the development of the nervous system during embryogenesis and metamorphosis. Development, growth & differentiation, 54(3), pp.420-437. https://doi.org/10.1111/j.1440-169X.2012.01343.x

Satterlie R A, 2011. Do jellyfish have central nervous systems? Journal of Experimental Biology, 214(8), pp.1215-1223. https://doi.org/10.1242/jeb.043687

Standal I B, Mozuraityte R and Slizyte R 2024. Quality of lipids during frozen storage of polychaete (Alitta virens) – a low trophic marine resource relevant for aquaculture feed. Journal of Aquatic Food Product Technology, 33(2), pp.161-176. https://doi.org/10.1080/10498850.2024.2316581

Tolstenkov O, Norland S and Chatzigeorgiou M, 2025. The evolution of embodied postural dynamics underlies behavioral diversity in benthic sessile chordate. bioRxiv, pp.2025-08. https://doi.org/10.1101/2025.08.28.672800

Varello R, Asnicar D, Boaga J and Cima F, 2023. Behavioural responses to ultrasound antifouling systems by adult solitary ascidians. Journal of Marine Science and Engineering, 11(6), p.1115. https://doi.org/10.3390/jmse11061115

Verdonschot P F, 2015. Introduction to Annelida and the class Polychaeta. In Thorp and Covich’s Freshwater Invertebrates (pp. 509-528). Academic Press. https://doi.org/10.1016/B978-0-12-385026-3.00020-6

Wahltinez, S J, Stacy N I, Hadfield C A, Harms C A, Lewbart G A, Newton A L and Nunamaker E A, 2022. Perspective: Opportunities for advancing aquatic invertebrate welfare. Frontiers in veterinary science, 9, p.973376. https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2022.973376/pdf

Wang G, Dong S, Tian X, Gao Q and Wang F, 2015. Sustainability evaluation of different systems for sea cucumber (Apostichopus japonicus) farming based on emergy theory. Journal of Ocean University of China, 14(3), pp.503-510. https://doi.org/10.1007/s11802-015-2453-z

Wang X, Wang Y, Wang Y, Storey K B and Chen M, 2023. Characterization and expression profile of transient receptor potential channels in sea cucumber Apostichopus japonicus. Frontiers in Marine Science, 10, p.1142982. https://doi.org/10.3389/fmars.2023.1142982

Yang H, Hamel J F and Mercier A eds, 2015. The sea cucumber Apostichopus japonicus: history, biology and aquaculture (Vol. 39). Academic Press.

Zapata F, Goetz F E, Smith S A, Howison M, Siebert S, Church S H, Sanders S M, Ames C L, McFadden C S, France S C and Daly M, 2015. Phylogenomic analyses support traditional relationships within Cnidaria. PloS one, 10(10), p.e0139068. https://doi.org/10.1371/journal.pone.0139068

]]> https://fishcount.org.uk/fish-count-estimates-2/numbers-of-other-farmed-invertebrates/feed 0 Wild-caught shrimp and prawn numbers https://fishcount.org.uk/related-links/wild-caught-shrimp-numbers https://fishcount.org.uk/related-links/wild-caught-shrimp-numbers#comments Tue, 07 Oct 2025 14:37:29 +0000 admin https://fishcount.org.uk/?page_id=16630 The staggering numbers of shrimps and prawns caught from the wild has been estimated for 20201 by researchers at Rethink Priorities. According to this research, an estimated 25 trillion (range 6.5 to 66 trillion) shrimps and prawns were caught from the wild that year1. These comprised
  • 19 trillion (range 4.1 to 55 trillion) Akiami paste shrimp (Acetes japonicus) and
  • 6.3 trillion (range 0.6 to 30 trillion) individuals of other species.

This research illustrates how reporting production of aquatic animals in tonnages masks the vast numbers of individuals affected. In terms of tonnage for 2020, the production of shrimps and prawns from farming (7.4 million tonnes2) was double that from wild capture (3.1 million tonnes2). However, in terms of midpoints of estimated numbers, wild-caught individuals (25 trillion1) were around 50 times greater than those farmed (450 billion3) due to their generally smaller size.

 

   

___________________________________________________________________________

1. Daniela R. Walhorn and Elisa Autric 2023. Shrimp: The animals most commonly used and killed for food production. Accessed here on 11 April 2025.
2. FAO 2024. Fishstat: Global aquaculture production 1950-2022 and Global capture production 1950-2022.
3. A. Mood and P. Brooke 2024. Estimated farmed crustacean numbers 2020 to 2022.

]]> https://fishcount.org.uk/related-links/wild-caught-shrimp-numbers/feed 0 Numbers of farmed molluscs https://fishcount.org.uk/fish-count-estimates-2/numbers-of-farmed-molluscs https://fishcount.org.uk/fish-count-estimates-2/numbers-of-farmed-molluscs#comments Mon, 06 Oct 2025 18:32:00 +0000 admin https://fishcount.org.uk/?page_id=16752 Global numbers of farmed molluscs, like other aquatic animals, are increasing as aquaculture rapidly expands. In the five years to 2022, reported annual global production of farmed molluscs increased from 17.5 to 18.9 million tonnes (FAO 2025), almost doubling that for the year 2000. Although 2022 production in the EU27 countries combined showed a 30% decline since 2000 (FAO 2025), it still represented over half a million tonnes.

Using a method similar to that used to estimate wild finfish numbers, we estimate that 390-1,000 (midpoint 700) billion1 molluscs were slaughtered in recorded global aquaculture production in 2022 as follows:

  • 360-900 billion bivalves
  • 31-95 billion unnamed molluscs
  • 4.1-8.8 billion gastropods.

Details of the estimate are available by species and by country. The most numerous species include the Japanese carpet shell (Ruditapes philippinarum). Most farmed molluscs were reared in China. EU27 countries combined accounted for 13-25 billion1 molluscs, of which 85% were sea mussels (Mytilidae).

Note that these estimates exclude on-farm mortalities. A review by Lupo et al. (2021) found that mortality risk in blue mussel (Mytilus edulis) and Mediterranean mussel (Mytilus galloprovincialis) varied across the seasons, increased with an elevated seawater temperature above a thermal threshold of 20 and 24°C respectively, decreased with protecting mussels from predation, and was associated with the presence of pathogens in blue mussel. Climate change foretells negative effects on mussel production, including through rising sea temperatures (Soliño & Figueras 2025), potentially increasing mortality numbers. These estimates also exclude mortalities of young mussels, spat, occurring during collection from the wild and in hatcheries.

These estimates also exclude farmed cephalopod molluscs, i.e. octopus, the farming of which is currently experimental and raises huge new animal welfare concerns (Lara 2021, Schnell et al. 2022), since no farmed cephalopod production tonnages are reported by FAO for 2022 (FAO 2025).


Implications for animal welfare

The rearing of bivalves like mussels and oysters is arguably more welfare-friendly than finfish and decapod aquaculture (Jacquet 2017), particularly when cultured on ropes suspended under the water rather than on the seabed (which involves dredging), due to their being generally sessile (semi-permanently attached) and filter-feeders. However, after ‘harvesting’ they are eventually killed by boiling or cooking (FAO 2009) which, if bivalves experience pain, may cause intense suffering.

In the wild, mussels attach themselves to rocks or other mussels using strong byssal threads produced from a gland located within their foot (ASC 2010-2025), which is also used for occasional locomotion (Deep Look 2023). In farming, mussel spats attach themselves to ropes, which would appear to offer a natural life that allows motivated normal behaviours.

Unlike farmed finfishes and decapods, which consume large numbers of inhumanely caught wild fishes as feed (Mood & Brooke 2024), bivalves do not require feed inputs (Naylor et al. 2021) and feed entirely off very small, naturally occurring, organisms in the water. In addition to phytoplankton, these include zooplankton and other tiny animals (Davenport et al. 2000), possibly numbering quadrillions annually2.

While there is sufficient scientific evidence to conclude that finfishes (Sneddon et al. 2014, Sneddon & Leach 2016), decapod crustaceans (Birch et al. 2021, Crump et al. 2022), cephalopod molluscs (Birch et al. 2021) and certain groups of insects (Gibbons et al. 2022) are sentient, there are almost no studies on bivalve sentience (de Souza Valente 2024). Scallops (free swimming bivalves) and clams have simple eyes and chemosensory organs, and they initiate escape swimming if a threat is detected, thus some integration of information and basic decision making occurs (Crook et al. 2011). Queen scallops (Aequipecten opercularis) have demonstrated increased cardiac activity when threatened by a predator (starfish) if they are unable to find refuge compared to when a refuge was available or the predator was absent (Kamenos et al. 2005). Mussel defensive responses to the presence of predators include producing more byssal threads to reduce risk of dislodgement by dexterous crabs (Garner & Litvaitis 2013), and trapping dogwhelks with byssal threads, leaving them immobilised (Petraitis 1987, Farrell & Crowe 2007). There is some evidence that mussels can ‘learn to fear’ their parasites, from a study by Selbach et al. (2022). In this study, blue mussels that had previously experienced parasitic load reduced their filtration rate when parasites later reappeared, compared to parasite-naïve conspecifics.


Conclusion

Given the large numbers used for food, research into the sentience of bivalves should be given a high priority (AAC 2024). Meanwhile, on a precautionary basis, since they may have the capacity to suffer, and since their numbers are very large, there is an ethical need to develop welfare codes for mollusc farming and ‘harvesting’, to provide for welfare as far as possible.

Welfare requirements during rearing are likely to include the availability of clean, unpolluted and plankton-rich water and keeping stocking density at a level that avoids undue competition for food, as well as mitigating mortality.

Since many bivalves are sold live direct to the consumer, welfare during transport and killing may prove more challenging. It may be possible to develop methods of humane killing (e.g. with food-grade anaesthetics), especially for the production of pre-cooked mussels and other bivalves targeted at welfare-conscious consumers.

 

A. Mood and P. Brooke. 6th October 2025.

___________________________________________________________________________

Notes

 1. rounded to 2 significant figures.

 2. Davenport et al. (2000) estimated that a medium sized (24 to 47 mm shell length) blue mussel inhales 120 small animals per day in spring. Assuming this is typical for a farmed mussel’s lifespan, and that none survive even if they are not digested, then based on this and an estimated lifespan of 6-24 months (ASC 2010-2025), each mussel kills between 22 and 88 thousand animals. If this consumption is typical for all farmed bivalve molluscs, then our estimated 360-900 billion1 bivalves ‘harvested’ globally in 2022 consumed between 7.8 and 79 quadrillion tiny creatures i.e. 7.8 x 1015 to 7.9 x 1016 individuals.

 

References

AAC (Aquaculture Advisory Council) 2024 Recommendation on Molluscan Welfare. AAC 2025-1.
https://aac-europe.org/wp-content/uploads/2024/11/1-AAC-Recommendation-on-Molluscan-Welfare.pdf.

ASC (Aquaculture Stewardship Council) 2010-2025 Learn more about mussels. https://asc-aqua.org/learn-about-seafood-farming/farmed-mussels/.

Birch J, Burn C, Schnell A, Browning H and Crump A, 2021. Review of the evidence of sentience in cephalopod molluscs and decapod crustaceans. https://www.lse.ac.uk/News/News-Assets/PDFs/2021/Sentience-in-Cephalopod-Molluscs-and-Decapod-Crustaceans-Final-Report-November-2021.pdf.

Crook R J and Walters E T, 2011. Nociceptive behavior and physiology of molluscs: animal welfare implications. ILAR journal 52(2) pp 185-195. https://academic.oup.com/ilarjournal/article/52/2/185/659960.

Crump A, Browning H, Schnell A, Burn C and Birch J, 2022. Sentience in decapod crustaceans: A general framework and review of the evidence. Animal Sentience 7(32) p 1. https://www.wellbeingintlstudiesrepository.org/animsent/vol7/iss32/1/.

Davenport J, Smith R J and Packer M, 2000. Mussels Mytilus edulis: significant consumers and destroyers of mesozooplankton. Marine Ecology Progress Series 198 pp 131-137. https://www.int-res.com/articles/meps/198/m198p131.pdf.

de Souza Valente C, 2025. Rethinking sentience: invertebrates as worthy of moral consideration. Journal of Agricultural and Environmental Ethics 38(1) p 3. https://doi.org/10.1007/s10806-024-09940-2.

Deep Look 2023. How does the mussel grow its beard? https://www.youtube.com/watch?v=4vWtkzwFnS0.

FAO (Food and Agriculture Organisation of the United Nations) 2009. Mytilus edulis Linnaeus 1758 Cultured Aquatic Species Information Programme. https://www.fao.org/fishery/en/culturedspecies/mytilus_edulis/en.

FAO 2025. FishstatJ: Global aquaculture production 1950-2022.

Farrell E D and Crowe T P, 2007. The use of byssus threads by Mytilus edulis as an active defence against Nucella lapillus. Journal of the Marine Biological Association of the United Kingdom, 87(2) pp 559-564. https://doi.org/10.1017/S0025315407055622

Garner Y L and Litvaitis M K, 2013. Effects of injured conspecifics and predators on byssogenesis, attachment strength and movement in the blue mussel, Mytilus edulis. Journal of Experimental Marine Biology and Ecology, 448, pp 136-140. https://www.westga.edu/share/documents/pubs/090576_1253.pdf

Gibbons M, Crump A, Barrett M, Sarlak S, Birch J and Chittka L, 2022. Can insects feel pain? A review of the neural and behavioural evidence. Advances in insect physiology, 63 pp 155-229. https://doi.org/10.1016/bs.aiip.2022.10.001

Jacquet J, 2017. Seafood in the future: Bivalves are better. The Solutions Journal 8(1) pp 27-32. https://scholarship.miami.edu/esploro/outputs/journalArticle/Seafood-in-the-future-Bivalves-are/991031799419902976/filesAndLinks?index=0.

Kamenos, N.A., Calosi, P. and Moore, P.G., 2006. Substratum-mediated heart rate responses of an invertebrate to predation threat. Animal Behaviour, 71(4), pp.809-813. https://doi.org/10.1016/j.anbehav.2005.05.026.

Lara, E., 2021. Octopus factory farming: a recipe for disaster. Compassion in World Farming International. https://www.ciwf.com/research/octopus-factory-farming-a-recipe-for-disaster/.

Lupo C, Bougeard S, Le Bihan V, Blin JL, Allain G, Azema P, Benoit F, Bechemin C, Bernard I, Blachier P and Brieau L 2021. Mortality of marine mussels Mytilus edulis and M. galloprovincialis: systematic literature review of risk factors and recommendations for future research. Reviews in Aquaculture 13(1) pp 504-536. https://archimer.ifremer.fr/doc/00642/75438/76573.pdf.

Mood A and Brooke P, 2024. Estimating global numbers of fishes caught from the wild annually from 2000 to 2019. Animal Welfare 33 e6. https://doi.org/10.1017/awf.2024.7.

Naylor R L, Hardy R W, Buschmann A H, Bush S R, Cao L, Klinger D H, Little D C, Lubchenco J, Shumway S E and Troell M, 2021. A 20-year retrospective review of global aquaculture. Nature 591(7851) pp 551-563. https://www.nature.com/articles/s41586-021-03308-6.

Petraitis P S, 1987. Immobilization of the predatory gastropod, Nucella lapillus, by its prey, Mytilus edulis. The Biological Bulletin 172(3) pp 307-314. https://doi.org/10.2307/1541710

Schnell A K, Browning H and Birch J, 2022. Octopus farms raise huge animal welfare concerns-and they’re unsustainable too. The Conversation. https://eprints.lse.ac.uk/115947/1/Octopus_farms_raise_huge_animal_welfare_concerns.pdf.

Selbach C, Marchant L and Mouritsen K N, 2022. Mussel memory: can bivalves learn to fear parasites?. Royal Society Open Science 9(1) p 211774. https://royalsocietypublishing.org/doi/10.1098/rsos.211774.

Sneddon L U, Elwood R W, Adamo S A and Leach M C, 2014. Defining and assessing animal pain. Animal behaviour 97 pp 201-212. https://www.wellbeingintlstudiesrepository.org/cgi/viewcontent.cgi?article=1068&context=acwp_arte.

Sneddon L U and Leach M C, 2016. Anthropomorphic denial of fish pain. Animal Sentience 1(3) p.28. https://www.wellbeingintlstudiesrepository.org/animsent/vol1/iss3/28/

Soliño M and Figueras A, 2025. The vulnerability of mussel aquaculture: Understanding environmental threats and future directions. Aquaculture 599 p 742196. https://www.sciencedirect.com/science/article/pii/S0044848625000821.

]]> https://fishcount.org.uk/fish-count-estimates-2/numbers-of-farmed-molluscs/feed 0 New Policy Roadmap Outlines Path to More Humane Slaughter Practices for Wild-Caught Finfish https://fishcount.org.uk/related-links/policy-roadmap-outlines-path-to-humane-slaughter-for-wild-caught-fish https://fishcount.org.uk/related-links/policy-roadmap-outlines-path-to-humane-slaughter-for-wild-caught-fish#comments Fri, 30 May 2025 14:44:34 +0000 admin https://fishcount.org.uk/?page_id=16691

A landmark report1, and a peer-reviewed review paper2, together present the first comprehensive, science-based strategy to support the adoption of humane slaughter methods for wild-caught fish at scale.

Key findings from the report, published in May 2025 by the Humane Slaughter Association, include:

  • Most wild-caught fish are slaughtered without stunning, often dying slowly by suffocation, bleeding, or live processing, with some species remaining conscious for several minutes to hours.
  • Humane stunning methods exist, such as electrical or mechanical techniques, but are rarely used in wild-capture fisheries due to cost, logistics, and lack of regulatory requirements.
  • Scientific evidence confirms fish sentience and supports urgent reform to minimise suffering at slaughter.
  • Continuous-flow in-water electrical stunning, a method already used in aquaculture, shows strong potential for adaptation in wild-capture fisheries.
  • Significant knowledge gaps remain, particularly around species-specific stunning parameters and practical deployment in mixed-species or high-volume fisheries.
  • Humane stunning may support industry benefits such as maintaining or improving product quality, enhancing shelf life, reducing labour demands, and improving crew safety.

The proposed six-stage roadmap offers a structured, collaborative path for industry, policymakers, and technology developers to adopt humane slaughter practices.

 —————————————————————————————-

1. James KL, Amarasinghe US, Herath TK, Jayasuriya NS, Lines J, Sneddon LU and Randall NP 2025. Humane slaughter of wild-caught fish. Recommendations for improving the welfare of over 1 trillion fishes caught in the wild annually. Humane Slaughter Association. https://www.hsa.org.uk/downloads/hsa15403—humane-slaughter-of-wild-caught-fish—report-designweb4-(3).pdf .

2. James KL, Aparicio SP, Jayasuriya NS, Herath TK, Lines J, Sneddon LU, Amarasinghe US and Randall NP 2025. Humane stunning or stun/killing in the slaughter of wild-caught finfish: The scientific evidence base. Animal Welfare, 34, e33, 1–15 . https://doi.org/10.1017/awf.2023.30 .

]]> https://fishcount.org.uk/related-links/policy-roadmap-outlines-path-to-humane-slaughter-for-wild-caught-fish/feed 0 Updated farmed fish & crustacean estimates https://fishcount.org.uk/fish-count-estimates-2/updated-farmed-fish-crustacean-estimates https://fishcount.org.uk/fish-count-estimates-2/updated-farmed-fish-crustacean-estimates#comments Sat, 07 Dec 2024 18:23:24 +0000 admin https://fishcount.org.uk/?page_id=16490 The numbers of farmed aquatic animals reared and killed for food is increasing annually, as aquaculture rapidly expands. Since 1990, farmed finfish numbers killed annually have increased nine-fold, to an estimated 124 billion (1.24 x 1011, range 78-171 billion) in 2019. Updated finfish estimates for 2020 to 2022 give respectively 126 billion (range 79-172 billion), 130 billion (range 84-177 billion) and 133 billion (range 86-181 billion).

Estimated numbers of farmed crustaceans killed in 2020 to 2022 were respectively 550 billion (range 280-830 billion), 590 billion (range 290-890 billion) and 630 billion (range 310-950 billion).

These estimates, which are available by species and country via the above links, do not represent total numbers farmed, due to mortalities during rearing and non-food production.

]]> https://fishcount.org.uk/fish-count-estimates-2/updated-farmed-fish-crustacean-estimates/feed 0 testpage1 https://fishcount.org.uk/testpage1 https://fishcount.org.uk/testpage1#comments Sun, 04 Feb 2024 10:20:50 +0000 admin https://fishcount.org.uk/?page_id=16364 qwerty qwerty

]]> https://fishcount.org.uk/testpage1/feed 0 Towards a strategy for humane fishing in the UK https://fishcount.org.uk/uk-strategy https://fishcount.org.uk/uk-strategy#comments Fri, 01 Nov 2019 13:51:35 +0000 admin http://fishcount.org.uk/?page_id=16116 We urge the UK authorities and food businesses to develop more humane commercial fishing. Current practices result in poor welfare to very large numbers of fishes. With the growing importance of fish welfare to UK and global consumers, this is a major opportunity to develop welfare-quality branding for UK fishing and to benefit a huge number of sentient animals.

A pdf version of this article is available here here

    Contents

  1. Introduction
  2. Wild catch fisheries – a major animal welfare issue
  3. Recent advances in humane slaughter of farmed fish
  4. Improving welfare of wild-caught fish
  5. Value-added benefits from ethical "care of the catch".
  6. Conclusion.
    Tables

  1. Numbers of animals killed in, or caught by, the UK for food annually.
  2. Application of potentially humane stunning/killing in wild catch fisheries worldwide.

 

1. Introduction

UK as leader in animal welfare
The UK has long been a leader in animal welfare. For example, the UK was the first country to end veal crates and sow stalls – after which a veal crate ban and a restriction on use of sow stalls were introduced across the EU1. In the UK, free range egg production has grown from almost nothing in the 1980’s to achieve more than half of total UK egg production (DEFRA, 2019) – despite the fact that free range eggs cost more to buy – and this also demonstrates that the UK consumer is prepared to pay more for higher welfare.

In fish welfare too, the UK is a leader and innovator. A high proportion of British farmed salmon and trout are now reared to RSPCA standards (see section 3), which require humane slaughter. The UK aquaculture industry, with government support, has developed electrical stunning machines (manufactured by the Scottish company “Ace Aquatec Ltd”) for the humane slaughter of farmed fish including trout (HSA, 2017; DEFRA, 2001 and 2006). Ace Aquatec Ltd is currently developing a humane stunning system for use on wild caught fish species (Ace Aquatec, personal communication, 2017) and a separate UK company (Crustastun) has previously developed a machine for the humane stunning/killing of decapod crustaceans.

Consumer concern for welfare of fish
British citizens, in common with their counterparts in the rest of Europe and internationally, care about the welfare of animals. A survey conducted for the EU Commission concluded that

“animal welfare is a very important issue for Europeans”

and

“The majority of Europeans are prepared to pay more for products sourced from animal welfare-friendly production systems”

and further that

“Since the last survey, there has been a shift in opinion, with most Europeans now considering there is not a sufficient choice of animal welfare-friendly products available in shops and supermarkets”

(EU Commission, 2016). This poll does not specifically cover fish species but separate market research has shown a willingness of consumers to pay more for better fish welfare in eight European countries studied, including the UK (Feucht and Zander, 2016).

Concern for the welfare of fish is growing internationally. A study of university-educated citizens from Bogota, Colombia, and Curitiba, Brazil into their perception of fish sentience, welfare and slaughter, reported that 80% and 72% of respondents, respectively, perceived fish as sentient beings; and 76% and 72% believed farmed fish should be included in humane slaughter regulation (Rucinque et al, 2017). Note also that most countries in the world are signed up to the codes of the World Organisation for Animal Health (the OIE) which recommend that only humane methods of killing should be used for farmed fish (OIE, 2019).

 

2. Wild catch fisheries – a major animal welfare issue

Welfare of fish during capture
Considerable suffering is caused to wild-caught fish during capture, landing and subsequent processing (Mood, 2010). Fish are likely to experience fear, pain and distress as they are, for example:

  • pursued to exhaustion by nets
  • crushed under the weight of other fish in trawl nets
  • raised from deep water and suffer decompression effects e.g. burst swim bladders
  • snared in gill nets
  • spiked with hooks to bring them aboard (if gaffing is used)
  • impaled live on hooks as bait (if live bait is used)
  • processed, e.g. gutted, while alive and conscious.

In many types of fishing the duration of capture can be very long, lasting hours or even days. Most commercially-caught fish that are alive when landed are not “slaughtered” but are left to asphyxiate or die during further processing which may include gutting, filleting and freezing while alive and conscious. Dutch research found that trawl-caught cod were still alive and conscious when tested after 2 hours of storage in air (Lambooij et al, 2012). Previous Dutch research found that, even after gutting, fish species take a considerable time (25-65 minutes) to lose consciousness (van de Vis and Kestin, 1996).

Number of fishes caught
It is estimated that the average number of wild fish caught globally each year, in the decade to 2016, is between 790 billion – 2,300 billion individuals (Mood and Brooke, 2019a). This estimate is based on FAO reported capture tonnages and average weights for fish species obtained from internet searches. The number of wild fish caught by UK commercial fishing fleets is around 2 billion per year (estimated at between 1.5 and 2.7 billion) as shown in Table 1 in comparison to other animal groups. This number greatly exceeds the 1.1 billion birds and 28 million mammals killed for food in the UK in 2017.

 

Table 1 Numbers of animals killed in, or caught by, the UK for food annually

Animal group Numbers of animals (millions)* Source
Mammals 28 FAOSTAT (data for 2017)
Birds 1,100 FAOSTAT (data for 2017)
Farmed fishes 25-110 Mood and Brooke, 2019b
Wild-caught fishes 1,500-2,700 Mood and Brooke, 2019c

         * To 2 significant figures
 

Welfare footprint
The magnitude of an animal welfare problem may be quantified as follows (WSPA, 2003):

Magnitude of welfare problem =  Severity   x   Duration   x   Number of animals affected.

For commercially-caught wild fish, the severity of suffering is likely to be high, the duration often extended and the numbers very large. This makes the treatment of fish during commercial fishing a major welfare issue.

 

3. Recent advances in humane slaughter of farmed fish

International welfare codes
The OIE has developed welfare recommendations for the slaughter of farmed fish (OIE, 2019; first adopted in 2010 and last updated in 2012) which state:

“As a general principle, fish should be stunned before killing, and the stunning method should ensure immediate and irreversible loss of consciousness. If the stunning is not irreversible, fish should be killed before consciousness is recovered.”

Recommended methods are the following mechanical methods:

  • percussive stunning (manual or by specially developed equipment)
  • spiking (iki jime)
  • shooting (for large fish such as tuna)
  • electrical stunning (in water or dry).

Chilling with iced water, asphyxiation by removal from water and exsanguination without stunning are discouraged, as they have been shown to result in poor fish welfare. The UK, like all other EU countries and nearly all other countries globally, has signed up to these codes.

International legal protection
We understand the EU Commission regards OIE Guidelines as the benchmark for assessing compliance with EU law – namely the EU Slaughter Regulation Article 3.1 (EU Council, 2009) which states that

“Animals shall be spared any avoidable pain, distress or suffering during their killing and related operations”

and which also states that its applicability includes fish species. Unfortunately, in the EU as a whole with the exception of Atlantic salmon, there is widespread non-compliance with the OIE slaughter guidelines, according to a report published by the EU Commission (IBF, 2017).

Norway is the largest producer of farmed fish in Europe2 and its legislation now requires farmed fish to be stunned prior to slaughter, with percussive and electrical stunning being the two methods used (Norwegian Animal Welfare Alliance, 2016; Norway Seafood Council, 2016). Czech animal protection legislation also specifies requirements for stunning before slaughter of fish (Czech National Council, 1992).

Note also that the UK Animal Welfare Act applies to all vertebrates, including farmed fish.

Humane slaughter of UK farmed fish
In the UK, humane slaughter methods for farmed fish are more widely applied. Atlantic salmon and large trout are typically percussively stunned; small trout are commonly electrically stunned. This has been facilitated over the years by a range of measures:

  • Published opinions by the UK government’s Farm Animal Welfare Committee e.g. FAWC 1996, 2014
  • Defra-funded research and development into humane fish slaughter methods
  • A high proportion3 of UK salmon and trout being produced to RSPCA-Assured certification standards which require humane slaughter (organic standards also require this)
  • Supermarkets’ own welfare standards requiring humane slaughter.

 

4. Improving welfare of wild-caught fish

A strategy for more humane commercial fishing will have two main objectives: firstly, to design the fishing method to reduce stress and injury during capture and, secondly, to employ methods of humane slaughter as soon as possible after landing the fish. As was discussed in a paper arising from a workshop on Fish Welfare and Fisheries held by the Fisheries Society of the British Isles (FSBI) in Japan 2008,

“some of the technologies developed for aquaculture, particularly those concerned with humane slaughter, might be applicable in commercial fisheries”;

(Huntingford and Kadri, 2009) and this is now beginning to happen.

 

4.1 More humane methods of capture

A key objective for improving the welfare of wild-caught fish is more “gentle” capture. In practice, gentler capture means designing and adapting the fishing method to achieve minimal levels of injury and mortality, and lower stress levels, in landed fish. A key part of this is that the fishing method should catch and land the fish more quickly.

To achieve clear welfare benefits from gentler capture, the capture and landing must be followed immediately by humane slaughter. There are some examples in the UK and abroad both of fishers using traditional methods of capture that lend themselves to more humane capture, eg fish traps (Mood, 2014) and flyshooting (which can land fish in prime condition because the fish are only in the actual net for a very short time before the net is hauled in (Montgomerie, 2015)), and of fishers using humane slaughter technology. Welfare-friendly approaches are needed for both small and large-scale fishing operations.

A welfare-friendly fishing operation will also need to avoid inhumane treatment of fish used for bait, and to minimise bycatch (including bycatch of non target species and undersized fish) and avoid habitat damage.

Opportunities for more gentle capture
From the point of view of the target species, providing a list of good and bad fishing methods is not straightforward because, firstly all types of fishing method cause stress, injury and potentially mortality; and secondly because the damage caused to wild-caught fish depends on other factors too: the sub type of fishing gear; the fishing context (eg fishing depth) and the size and species of the fish themselves. The ultimate goal is that a fishery can demonstrate that is it achieving low levels of injury and stress (and minimal bycatch) during the capture process.

One review has systematically analysed published research for the effect on fish mortality and injury of different fishing gear types/characteristics (Veldhuizen et al, 2018). The researchers’ findings, they say, “provide options to reduce injuries and mortality from commercial capture fisheries”. According to this review, the design of fishing gear, e.g. shape of hook, affects levels of injury and the following increased the injury and/or mortality of fish during capture:

  • longer fishing duration
  • higher density in trawl nets (NB longer duration will lead to higher density)
  • capture at greater depths due to
    • change in pressure
    • change in temperature
    • may take longer to land
  • large change in water temperature during capture (ie if surface water warmer than the depths)
  • longer air exposure increased mortality
  • trawls and seines have higher mortality than hooks, gillnets and traps
  • mortality is higher in smaller fish.

Consideration of the factors influencing levels of damage or stress to fish will help in the development of gentler capture methods. For example, a study of the welfare of wild-caught plaice, one of Europe’s commercially most important species, identified some key indicators for better welfare during the capture process for this species (Hürlimann et al, 2014):

  • nets of soft material and knotless
  • short hauling ie towing duration where plaice is in the net for a short time period
  • no/small quantities of bycatch (unwanted materials, debris and other organisms)
  • low hauling speed so that plaice is still able to swim within the net and can still move.

 

Duration of capture
As discussed in section 2, the magnitude of an animal welfare issue may be measured as the product of the severity of suffering, the duration and numbers of animals affected. Hence reducing the duration of the capture process would reduce the distress caused to wild caught fish. A longer duration of fish capture increases the period over which fish suffer and, for several reasons, can also result in a greater severity of distress eg by increasing the crowding and crushing in the net during trawling. Fish may incur injury while trapped in gillnets or on hooks, struggling to escape and unable to evade predators (Mood, 2010).

Landing fish
The process of landing caught fish onboard should be as gentle as possible and be followed immediately by humane slaughter. Time out of water should be absolutely minimised, as should crowding before landing. Handling methods that cause less stress should be used, eg well-designed pumps developed for aquaculture to move fish without injury. If braille nets are used to lift the fish then they should carry water. Where fish are to be handled manually, wet hands should be used or soft wet gloves should be worn (Hürlimann et al, 2014).

For fish species that experience injury with sudden changes in pressure, these should be reduced by bringing the gear to the surface more slowly to ensure a more gradual change in depth and pressure, though the ideal surfacing speed (at which fish are retained in the gear but sustain less pressure injuries) is not known (Veldhuizen et al, 2018).

 

4.2 Humane slaughter in commercial fishing

Humane slaughter is arguably the most important requirement for improving the welfare of wild caught fish. The welfare benefits of more gentle and quicker capture may not be realised if fish are not subsequently humanely slaughtered but allowed to die during processing or exposure to air. On the other hand, humane slaughter is likely to benefit welfare even where gentler or faster capture has not been achieved, since research has shown that landed fish can remain conscious (and therefore likely to be suffering) for a long time, eg trawl-caught cod where found to be conscious when tested after two hours of onboard storage in dry bins (Lambooij et al, 2012).

In this section we describe the basic methods of humane slaughter as recommended by the OIE for farmed fish; how these methods are beginning to be applied for wild-caught fish and some key opportunities for this. In the killing methods described in this section, we emphasise that these are potentially humane killing methods but need to be implemented properly to achieve the humane objective.

Dry and semi-dry electrical stunning
Electrical stunning systems have been developed for en mass humane slaughter in fish farming and are beginning to be used on fishing vessels. Electrical stunning must be performed correctly or it can be very painful and paralysis may occur without loss of consciousness (IBF, 2017).

In “dry” stunning, an electric current is administered to a fish, after de-watering, on a conveyor belt. Fish may be humanely stunned (ie rendered unconscious within 1 second) by electrical stunning if the necessary electrical parameters are identified for the species (usually in laboratory tests) and achieved in practice. It must also be ensured that fish are subsequently killed before any recovery from the stun. The OIE also refer to “semi-dry” stunning (OIE, 2019). In semi-dry systems, there is a water-filled buffer in front of the stunner and the fish may be sprayed with water between the buffer and the stunner. This reduces the duration of stress caused by being taken out of water.

A collaboration between Dutch and Norwegian scientists has been researching how onboard dry electrical stunning might be achieved using a “STANSAS” stunning machine manufactured by the Norwegian company Optimar (formerly Seaside). Researchers have identified, or partly identified, key parameters for the dry stunning of several wild-caught species including cod and haddock (Lambooij et al, 2012); plaice and dab (Bracke et al, 2013); turbot and sole (Daskalova et al, 2016); mackerel (Anders et al, 2019). The stunner can also be used for large crustaceans such as crabs and lobsters.

A Stansas dry stunner is now in use commercially for the humane slaughter of plaice caught by the Dutch Ekofish vessels “PD147” and, more recently, the “Spes Nova”. Marketed as humanely killed, plaice caught by the PD147 went on sale in all Dutch PLUS supermarkets from June 2015 (Visserijnieuw, 2015). The fish stunner dry stuns the fish, before they are killed in iced water, although more research may be still needed to optimize the device (PALSED, 2014; Hürlimann et al, 2014). On the newer vessel, welfare has been improved by keeping the plaice in water prior to the stunning process by landing the netted fish into a tank of water. The Dutch government is currently funding a five-year research project (see Wageningen University, 2019) to test parameters for semi-dry and in-water stunning of demersal (bottom dwelling) fish, and to address some technical issues in using the stunner for wild caught fish (e.g. ensuring fish enter the stunner one at a time and preventing debris entering, a particular problem with demersal fish caught by bottom trawling).

Electrical dry stunning for whitefish has been implemented onboard several national and international fishing vessels, including on some Scottish seiners in Norway, to facilitate easier handling of fish and immediate bleeding after capture (Aursand et al, 2015). Disappointingly, it appears that electric current is applied at a relatively low voltage to immobilise the fish rather than to render them unconscious, as is required by legislation in the Norwegian aquaculture industry (Aursand et al, 2015).

Electrical in-water stunning
With in-water electrical stunning, a current is passed though the water containing the fish. The fish are stunned immediately, and remain unconscious until killed (eg by chilling unconscious fish in ice water), if the voltage and duration of the current are sufficient. These will depend on the species and the conductivity of the water. With in-water stunning the fish do not need to be removed from water (which is highly stressful to fish) for more than a fraction of a second during the stunning process and so, in principle, in-water stunning may be less stressful to fish than dry stunning (IBF, 2017). Stunning parameters for in-water stunning tested with EEG measurements (ie measurements of brain activity which are the most reliable indicators of consciousness/unconsciousness) are not available.

A Scottish firm, Ace Aquatec, is developing in-water stunners for wild-caught cod, haddock and saithe (personal communication, 2017) which can also be used on crustaceans. Electrical in-water stunning is used to stun (prior to bleeding) longline-caught Alaskan cod as soon as each fish is individually landed on the “Blue North” fishing vessel, as part of the companies “humane harvest” initiative.

Percussive stunning
Percussive stunning is the application of a blow to the head manually or by using a device. It should be performed with sufficient force and accuracy to produce an immediate stun, ie within one second (since a blow to the head is painful when the stun is not achieved immediately), and recovery should not occur (IBF, 2017). To ensure that death ensues without recovery, the percussive stun should be followed immediately by bleeding. Manual percussive stunning is used by some artisanal fishers such as Usan Salmon Fisheries Ltd (Scotland) and Alaskan’s Own troll-caught Pacific salmon (Mood, 2014).

Automatic percussive stunning devices have been developed for some species in fish farming and are more reliably accurate than manual stunning. In some cases, the fish are directed to the stunning machines without removing them from water or manual handling (both very stressful to fish) prior to stunning. However, percussive stunning is not suitable for all types of fish. Automatic percussive stunning machines have been used (followed immediately by manual bleeding) for the humane killing of wild Alaskan salmon caught in small purse seines by the company “Wild Salmon Direct” (Wild Salmon Direct, 2006; Mood, 2014). The main challenge for onboard percussive stunning might be the variability of fish sizes caught (see IBF,2017), presumably greater for wild than harvest-size farmed fish.

Spiking (iki jime)
In spiking (also called “ike jime”) a fish is killed by inserting a spike into the brain. If this is performed accurately, the fish can become unconscious immediately. This is a traditional method used in some longline and trolling fisheries where fish have their brains spiked as soon as they are landed, which delays onset of rigor and benefits quality (Gregory, 1998). Spiking has not yet been automated for fish farming due to the difficulty in accurately locating the brain with varying fish size.

A hand held device called the “Ikigun” has recently been developed in New Zealand to enable anglers to easily employ the spiking method (Fishing World, 2013). It is marketed as a

“simple, humane way to kill fish that improves taste.”

and suggests another option for artisanal fishers who handle fish individually, though it is not marketed for high volume commercial fishing (see www.ikigun.com). The Australian government has developed codes that recommend spiking as a method of humane killing in its commercial rod and handline fisheries (AAWS, 2012) and has produced a video explaining how to do it (see www.ikijime.com).

Key welfare opportunities for wild caught fish
The key areas of opportunity for improving the welfare of commercially-caught fish are:

  1. to adapt automated humane stunning/killing systems used in aquaculture for use onboard fishing vessels
  2. to ensure that stunning machines on fishing vessels are aiming at, and achieving, humane stunning (immediate anaesthesia lasting until death)
  3. to widen the use of traditional manual methods of humane stunning/killing in artisanal fisheries (namely percussive stunning and spiking)
  4. the development of semi-automatic devices to improve on the methods in 3.

Examples of 1, 3 and 4 above are shown in Table 2.

 

Table 2 Application of potentially humane stunning/killing in wild catch fisheries worldwide

Stunning/killing method Manual Semi-automatic
(hand-held or hand-fed device)		 Automated system
Percussive stunning Some artisanal fisheries e.g. Usan fisheries (Mood, 2014; fair-fish, 2007) Wild Salmon Direct (experimental)
Spiking (iki jime) E.g. Japanese market and some long line fisheries (for quality) Ikigun used in recreational fishing
Electrical Stunning (in water) Blue North.
Ace Aquatec stunners (potentially)
Electrical Stunning (dry) Ekofish (Optimar stunner, previously known as “Stansas” or “Seaside”).
Optimar stunners are installed on fishing-vessels in Norway, Iceland, Holland, the US and Canada (personal correspondence, 2017).
Electrical stunning of crustaceans (in water) Ace Aquatec stunners (potentially)
Electrical stunning of large crustaceans eg crabs and lobsters (dry) Crustastun (single stunner for restaurants) Crustastun (reportedly used for Tesco and Waitrose).
Hitramat AS (Optimar stunner for edible crabs (Roth and Grimsbø, 2013)

 

4.3 Welfare quality assurance
The killing methods described in this document need to be implemented properly to achieve the humane objective. Van de Vis et al (2016) propose the three main steps to establish effective humane stunning and killing of farmed and captured fish. In the context of electrical or percussive stunning, the basic steps are:

  1. In a laboratory setting, determine the conditions required for an effective stun without avoidable stress, pain and fear. EEG and ECG measurements of fish are needed in addition to behavioural observations because fish not displaying signs of consciousness can still be conscious, as evidenced by measurements of brain activity.
  2. Test the stunning or stunning/killing method in a (semi-) commercial setting. This includes physical measurements of the stunning equipment (such as strength of current for electrical stunning and air pressure for percussive stunning) and behavioural observations of the fish. The researchers stress that caution is needed in the interpretation of behavioural observations of fish since fish may still be conscious but unresponsive due to, for example, paralysis or exhaustion.
  3. Once industry has installed equipment and adopted humane stunning, ongoing control (measurements and corrective action where needed) to ensure effective stunning. To achieve this, a process-oriented Quality Assurance system could be used as described by (Van de Vis et al (2012).

 

5. Value-added benefits from ethical “care of the catch”

The term “care of the catch” is sometimes used to mean better handling to achieve product quality and value. Consumers will increasingly expect ethical care of the catch to mean more humane treatment as well as product quality. Ethical care of the catch can bring several benefits.

Welfare quality and premium
With growing pressure on wild fish stocks, it makes perfect sense to increase the value of each animal caught. Improving animal welfare provides an opportunity to add value and to provide a superior product that can attract a welfare premium.

Food quality
Humane killing of fish can bring improved food quality by reducing pre-slaughter muscle activity, which is one of the reasons that iki jime is traditionally used. SINTEF research scientist, Dr Hanne Digre, found that reducing the stress experienced by caught fish improves the eating quality (SINTEF, 2016). According to the US company Blue North’s website, the humane slaughter of wild-caught cod on its pioneering vessel (see section 4.3) improves nutritional and eating quality as well as shelf life.

Worker health and safety
Researchers at SINTEF, Norway, have been developing electrical stunning of trawl-caught cod and haddock. SINTEF researcher, Dr Digre, argues that electrical stunning can benefit fishers as well as fish welfare. Currently, it is common to gut fish manually, which is a cumbersome and hazardous job for the fishermen, and is made safer, easier and more efficient by stunning the fish first (SINTEF, 2016).

Sustainability
Adding welfare and quality value to each fish can help to maintain incomes as part of sustainable fisheries management. Blue North’s care of the catch enables it to efficiently utilise proteins that currently go to waste (Blue North, 2017b).

 

6. Conclusion

The UK should act quickly to develop systems for humane killing onboard its fishing vessels and more gentle methods of capture and landing of fish. The opportunity to improve welfare is substantial.

We understand that food businesses are interested in being able to provide humanely caught fish to their customers. We expect that increasing numbers of fishers will choose to improve the way they handle their catch, given the right knowledge and technology. Animal welfare can help fishers add value to each fish and make it a superior product.

Development of humane fishing would benefit greatly from industry-wide initiatives and the support of government. The UK Government has helped to solve similar problems in UK aquaculture, working together with UK industry and scientists, and has a key role in the development of more humane fisheries.

 
A Mood and P Brooke, November 2019.

   

___________________________________________________________________________

1. Veal crates were banned in the UK from 1990 and in the EU from 2007; Sow stalls were banned in the UK from 1999 and restricted (banned beyond first month of pregnancy) in the EU from 2013.
2. 1.3 million tonnes in 2017 (FAO, 2019).
3. We believe 70-80% of salmon and over half of trout.

References
See the pdf version of this article here.

]]> https://fishcount.org.uk/uk-strategy/feed 0 List of all fishcount estimates https://fishcount.org.uk/studydatascreens/2016/fishcount_estimates_list.php https://fishcount.org.uk/studydatascreens/2016/fishcount_estimates_list.php#comments Sun, 20 Jan 2019 21:42:08 +0000 admin http://fishcount.org.uk/?page_id=15599 https://fishcount.org.uk/studydatascreens/2016/fishcount_estimates_list.php/feed 0 Analysis of reduction in estimated fish numbers between 1999-2007 and 2007-2016 https://fishcount.org.uk/studydatascreens/2016/fishcount_estimates_analysis.php https://fishcount.org.uk/studydatascreens/2016/fishcount_estimates_analysis.php#comments Sun, 20 Jan 2019 20:20:59 +0000 admin http://fishcount.org.uk/?page_id=15554 https://fishcount.org.uk/studydatascreens/2016/fishcount_estimates_analysis.php/feed 0 Numbers of fish caught from the wild each year https://fishcount.org.uk/fish-count-estimates-2/numbers-of-fish-caught-from-the-wild-each-year https://fishcount.org.uk/fish-count-estimates-2/numbers-of-fish-caught-from-the-wild-each-year#comments Sun, 20 Jan 2019 16:49:05 +0000 admin http://fishcount.org.uk/?page_id=15496

Japanese jack mackerel (Trachurus japonicus).
An estimated 1.1 billion individuals of this species are caught each year.
Credit: Nemo's great uncle.

 
Our recent estimates of wild-caught fish numbers have been published in a peer-reviewed paper in the journal Animal Welfare. We estimate that 1.1-2.2 trillion wild fishes were caught annually, on average, during 2000-2019. Approximately half of these were used for reduction to fishmeal and oil, based on 2010 data. We have since extended this estimate to the period 2003-2022, for which estimates are available by species, country and by individual year.

We previously estimated (in 2019) that between 0.79 and 2.3 trillion* fish (ie 790,000,000,000 to 2,300,000,000,000) were caught from the wild globally each year for 2007-2016. Details of the 2019 estimate are available here.

This is an update to an earlier estimate (in 2010) of between 0.97 and 2.7 trillion* fishes caught from the wild globally each year for 1999-2007. Details of the earlier 2010 estimate are available here.

The fall in wild-caught fish numbers between the two estimates is very largely due to a decline in Peruvian anchovy catch between 1999-2016 and, to a lesser extent, a decline in capelin, Japanese anchovy, sandeels, European anchovy and Black and Caspian Sea sprat. See below for a more detailed analysis.

 

 

* rounded to 2 significant figures.

]]> https://fishcount.org.uk/fish-count-estimates-2/numbers-of-fish-caught-from-the-wild-each-year/feed 0