{"id":353668,"date":"2026-01-05T17:24:17","date_gmt":"2026-01-05T17:24:17","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/353668\/"},"modified":"2026-01-05T17:24:17","modified_gmt":"2026-01-05T17:24:17","slug":"seven-million-lice-eating-fish-died-at-salmon-farms","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/353668\/","title":{"rendered":"Seven million lice-eating fish died at salmon farms"},"content":{"rendered":"

\n Detailed research by a campaigner has uncovered the first estimate of the total number of so-called cleaner fish lost in salmon farms around \u00adScotland\u2019s coast. The figure has been calculated from information released by the Scottish Government<\/a>.\n<\/p>\n

\n The data was not examined by the Government\u2019s Scottish Animal \u00adWelfare Commission (SAWC) before it published its report on cleaner fish in November 2025. The report \u00adaccepted that losses \u201cmay be very high\u201d, but didn\u2019t recommend any changes in current practice, saying that more research was needed.\n<\/p>\n

\n Campaigners said the death toll was \u201cunacceptable\u201d, \u201cappalling\u201d and \u201ca colossal waste of life\u201d, and \u00addescribed the use of cleaner fish as \u201c\u00addesperately cruel\u201d and \u00ad\u201cunethical\u201d. They \u00adcriticised the SAWC report as \u00ad\u201cdeeply flawed\u201d, and called on \u00adScottish ministers to require the \u00adroutine publication of industry \u00adfigures on cleaner fish deaths.\n<\/p>\n

\n READ MORE: Scottish political parties react to US bombing Venezuela as Nicolas Maduro ‘captured’<\/a>\n<\/p>\n

\n The SAWC said that a total of \u00adseven million cleaner fish deaths was \u201cwithin the same range\u201d as \u00adestimates from different salmon farms. It stressed that this was one of its \u201c\u00adbiggest \u00adconcerns\u201d and was why the aim should be to phase out the use of cleaner fish.\n<\/p>\n

\n The salmon industry did not \u00addispute the figure, but stressed that it had high welfare standards and acted \u201cresponsibly\u201d. The Scottish Government said it was working to improve welfare standards for cleaner fish.\n<\/p>\n

\n Sea lice infestations have long been a major problem for salmon \u00adcompanies because they can \u00adweaken and kill farmed fish. Pesticides are used to kill them, and there are a \u00advariety of treatments aimed at \u00addetaching them from salmon.\n<\/p>\n

\n But because lice can become \u00adresistant to pesticides and salmon can be harmed by removal treatments, the use of cleaner fish to graze the lice has grown since 2008. Two fish have mainly been used, ballan wrasse and lumpfish, which are either caught in the wild or bred in farms.\n<\/p>\n

\n The Scottish Government\u2019s Marine Directorate and Fish Health<\/a> Inspectorate do not publish statistics on the number of cleaner fish used or how many die. But they have released data under Freedom of Information law on transfers to and from salmon farms, as well as hundreds of inspection \u00adreports on individual farms.\n<\/p>\n

\n For the last three years \u00adRoddie Macpherson, a researcher and \u00adcampaigner from the Black Isle, has been analysing the data and \u00adreading the reports. A 76-year-old retired planning consultant, his study of 138 salmon farms suggested they have used more than 22 million cleaner fish since 2020, including 16 million lumpfish and six million wrasse.\n<\/p>\n

\n According to the SAWC report, most of the cleaner fish are killed by salmon farmers at the end of \u00adproduction cycles, which last one or two years, rather than being \u00adre-used. There are fears that they could \u00adtransmit diseases or lice.\n<\/p>\n

\n Macpherson has now also \u00adanalysed transfer data and inspectors\u2019 \u00adreports to estimate the total number of \u00adcleaner fish that have been killed \u00adduring salmon production. He has concluded that between 2020 and the end of 2024, at least seven \u00admillion have died, including 5.8 million \u00adlumpfish and 1.2 million wrasse.\n<\/p>\n

\n In many cases, the cause of death is not given, with some fish health inspectors describing them as \u201cblack losses\u201d, a term used in agriculture to describe deaths from causes \u00adunknown.\n<\/p>\n

\n But some inspectors\u2019 reports do identify a range of causes, \u00adincluding viruses, bacteria and \u201chandling\u201d. On several occasions, they attributed mass cleaner fish deaths to \u00adfreshwater or warm water treatments used by fish farms to remove lice from salmon.\n<\/p>\n

\n <\/p>\n

\n Staff at farms were reported as \u00adsaying that they had difficulties \u00adseparating cleaner fish from salmon before such treatments. Fish health inspectors referred a few incidents since 2020 to the UK \u00adAnimal and Plant Health Agency, but there is no record of any subsequent \u00ad enforcement \u00adaction.\n<\/p>\n

\n Macpherson stressed that seven million deaths was an \u00adunderestimate because it excluded incidents in which fewer than 10,000 wrasse or 20,000 lumpfish died. It was also \u00adlimited to just 69 of the bigger salmon farms, omitting 69 smaller farms.\n<\/p>\n

\n The Ferret reported in August 2025 that Scotland\u2019s biggest fish farming company, Norwegian-owned Mowi, was going to stop using lumpfish to clean lice from salmon. This followed the loss of 135,000 lumpfish and wrasse from a salmon farm in Torridon.\n<\/p>\n

\n Macpherson described the failure to publish cleaner fish statistics as a \u201chuge hole\u201d. Scottish ministers should require \u201croutine publication\u201d of their deaths and known causes, he argued, \u201cso that the public can judge whether using cleaner fish is an \u00adacceptable practice.\u201d\n<\/p>\n

\n He pointed out that the industry had told SAWC that it kept weekly records of cleaner fish deaths. The commission\u2019s failure to follow this up had resulted in its recent report being \u201cfatally flawed\u201d, he told The Ferret.\n<\/p>\n

\n The Coastal Communities \u00adNetwork Scotland, which brings together 30 groups concerned about the \u00admarine environment, pointed out that using \u00adanimals to remove parasites from livestock was unusual in farming. \u201cNo other farming system would be allowed to kill them all afterwards,\u201d said the network\u2019s fish farming spokesperson, John Aitchison.\n<\/p>\n

\n He added: \u201cScottish ministers \u00adinsist that the reporting of \u00admortality of farmed fish is fit for purpose, but the painstaking work needed to \u00adreveal these millions of hidden deaths for the first time shows that it is \u00adnothing of the sort. It is high time that the Scottish Government came clean about the scale of this issue.\u201d\n<\/p>\n

\n Aitchison described the death toll as \u201cappalling\u201d and \u201cunacceptable\u201d, and argued that it was \u201cunethical\u201d to use cleaner fish. \u201cThe Scottish Government is deliberately looking the other way,\u201d he said. \u201cThis has to stop.\u201d\n<\/p>\n

\n The Scottish Greens<\/a> reiterated their call for a \u201cpause\u201d on new salmon farms. \u201cThis analysis is very concerning and raises big questions,\u201d said Green MSP Ariane Burgess.\n<\/p>\n

\n <\/p>\n

\n \u201cThe reality is that too many \u00adcompanies have been raking in huge profits while failing to make the kind of improvements that are so badly needed in terms of animal welfare or our environment.\u201d\n<\/p>\n

\n The campaign group Animal Equality UK described the use of cleaner fish as \u201cdesperately cruel\u201d and \u201ca colossal waste of life\u201d. It called on Scotland to \u201cmove away from cleaner fish use urgently\u201d.\n<\/p>\n

\n The SAWC report concluded that \u201cfurther research\u201d was needed to find out the causes of \u201cunexplained \u00adlosses\u201d of cleaner fish. \u201cThe losses may be very high, and the \u00admissing \u00adanimals are likely to have died and likely \u00adexperienced poor \u00adwelfare \u00adbefore death due to disease or \u00adpredation,\u201d it said.\n<\/p>\n

\n The commission\u2019s chair, Professor Cathy Dwyer, highlighted evidence of cleaner fish death rates of between 22% and 57% at different salmon farms.\n<\/p>\n

\n <\/p>\n

\n \u201cMr McPherson\u2019s figures \u00adsuggest 32% mortality, which is within the same range,\u201d she told The Ferret.\n<\/p>\n

\n \u201cWe suggest that this level of \u00admortality is one of the biggest \u00adconcerns in the use of cleaner fish in the industry and also note that \u00adcleaner fish are typically culled at the end of deployment.\u201d\n<\/p>\n

\n She added: \u201cWe did not recommend that, currently, the use of cleaner fish should be immediately halted, due to our concerns about other methods of sea louse treatment for salmon \u00adwelfare.\n<\/p>\n

\n \u201cHowever, we do recommend that other methods should be sought and the use of cleaner fish phased out,\u201d Dwyer added.\n<\/p>\n

\n The UK Government<\/a>\u2019s Animal and Plant Health Agency (APHA) said it was unable to comment on \u00adindividual cases. \u201cAPHA treats all \u00adreports of \u00adsuspected cases of poor welfare at salmon farms seriously,\u201d said a spokesperson.\n<\/p>\n

\n The Scottish Government promised to deliver better welfare for cleaner fish.\n<\/p>\n

\n \u201cWe are progressing work to \u00adimprove welfare standards for farmed fish by bringing forward guidance \u00adunder the Animal Health and \u00adWelfare (Scotland) Act 2006, which will \u00adextend to cleaner fish,\u201d a spokesperson said.\n<\/p>\n

\n A spokesperson for Salmon \u00adScotland, which represents salmon farming companies, said: \u201cScottish salmon farmers operate to some of the highest health, welfare, and \u00adenvironmental standards in the world, acting responsibly for all fish in their care, including cleaner fish.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"Detailed research by a campaigner has uncovered the first estimate of the total number of so-called cleaner fish…\n","protected":false},"author":2,"featured_media":353669,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[1397,90,56,54,55],"class_list":["post-353668","post","type-post","status-publish","format-standard","has-post-thumbnail","category-environment","tag-environment","tag-science","tag-uk","tag-united-kingdom","tag-unitedkingdom"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/353668","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=353668"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/353668\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/353669"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=353668"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=353668"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=353668"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}