NASCO nonsense: Last week, NASCO posted on their website the Final Report on the Review of the Effect of Salmon Aquaculture on Wild Atlantic Salmon Populations (CN(25)17). This is one of the documents intended for discussion at the forthcoming NASCO annual meeting in Cardiff at the beginning of June. The document is intended to provide the NASCO Council with a final report on the efforts to provide the latest scientific knowledge on the impacts of sea lice and escapes on wild salmon.
And what is this latest scientific knowledge? Well, I can tell you that this latest scientific knowledge is in fact the same old scientific knowledge that is promoted by those with strong connections to the wild fish lobby, such as NASCO.
The final report states that ‘Evidence indicates that salmon lice from aquaculture negatively affects wild Atlantic salmon populations. Systematic review data shows a reduction in survival and adult returns in salmon exposed to salmon lice.
NASCO’s report goes on to say that ‘increased mortality (presumably of wild salmon) linked to salmon lice infestations is documented in countries with significant salmon aquaculture including Norway, Ireland and Scotland suggesting a widespread impact across the North Atlantic.
Finally, NASCO say that studies show a degree of bias due to limitations in study design including inadequate documentation of salmon lice levels during out migration and effectiveness of anti-parasitic lice treatments. These biases suggest that the true impact of salmon lice on wild salmon populations may be greater than current estimates.
However, the real bias is that NASCO and their angling friends (39 NGO groups who are allowed to be observers) still wrongly believe that salmon farms have a detrimental impact on wild fish, yet despite extensive desk research have been unable to provide any hard evidence of damage. It is all circumstantial, yet there is now plenty of evidence to show that salmon farms are not to blame. The problem is that NASCO aren’t interested in such inconveniences. They certainly aren’t prepared to listen to anyone who is not a recognised representative body. They used to recognise the International Salmon Farmers Association but the last time there was any interaction, NASCO refused to let them speak at their annual meeting.
The NASCO final reports states that it was agreed to fund a study to provide the latest scientific knowledge at the annual meeting in 2021. The proposed approach was to produce a State of Knowledge paper where the goal was to conduct a systematic review and potential meta-analysis of the effect of sea lice on wild fish. Together with a similar approach on escapes, the project cost was €83,000.
An expert group was formed which later recruited further ‘experts’ but did not include any representation from the salmon farming industry. The research areas of those involved in the project provide a clear indication of how they view any relationship between salmon farms, sea lice and wild fish. It was obvious from the outset what conclusions the researchers would reach.
The project consisted of a literature search, about which I have previously written. The group found only 17 papers out of over two thousand that had any relevant data. I have attempted to find out which papers these are, but it is impossible to get a straight answer. One of the original expert group members wasn’t even aware of these 17 papers.
The completed literature search was then subjected to a ‘standardised critical appraisal’ intended to highlight those papers with the most rigorous experimental design. Based on the results, an evaluation was made whether there was sufficient empirical data to undertake a meta-analysis of randomised control studies. According to the financial plan, €27,000 was allocated to the literature search and critical appraisal, a sum which I could have saved them since the outcome was a forgone conclusion.
One of the members of the sea lice expert group is Knut Wiik Vollset, who was for a time head of the Norwegian Sea Lice Expert Group. In 2015, he was lead author of a paper titled ‘Impacts of parasites on marine survival of Atlantic salmon: a meta-analysis’. If there was sufficient data to produce this paper in 2015, then surely, there is also sufficient empirical data to conduct a similar meta-analysis ten years later. The reasoning for this meta-analysis ten years ago was there was part of the scientific community who could not accept the findings of the 2013 Jackson paper which at the time, was the largest study of its type. Jackson found that the impact of sea lice on wild fish was about 1%. The paper was published in a high-ranking journal but despite its credibility, it was not accepted by the scientists and wild fish community because it contradicted the established. They criticised the paper at the time and subsequently attempted to dilute its key findings by burying the data within such meta-analyses.
It is likely that Knut Wiik Vollset, as a member of the original NASCO expert group will also be the lead author on the proposed paper. However, the final report also documents various meetings that took place between the project team during 2024 and 2025. In total there were 5 meetings between July and December 2025 and a further 4 in January and February 2025. It is interesting to see who attended these meetings and how often.
Knut Wiik Vollset attended six of the nine meetings. He is one of the original members of the NASCO Expert Group. The other members listed as experts on sea lice were Eva Thorstad from NINA who did not attend any meetings at all and Simon Joes from Canada who attended one meeting. The last member of the Expert Group, Damien Brady from the US, who is listed as an expert in coastal ecology also attended two of the nine meetings.
In May 2022, the Expert Group recruited Steven Cooke from the Canadain Centre for Evidence Based Conservation at Carleton University. His job was to undertake the critical appraisal of the results of the literature search. Professor Cooke attended one meeting but his colleague Trina Rytwinski attended four of the meetings.
The Expert Group also recruited four more experts to be part of a subgroup. These were Sussie Dalvin from IMR in Norway who is not recorded as attending any meeting. Sandy Murray of Scottish Government Science, Frank Nilsen of the University of Bergen and Sam Shephard, formerly of Inland Fisheries Ireland, who all attended just one meeting.
I mention these meeting because what is most interesting is that one person attended all nine meetings. This was Marie Lie Larson (sic) from the Fridtjof Nansen Institute. None of the NASCO documents record how Mari Lie became part of the team of these sea lice experts. However, seven of the meetings involved her and just one other person. Three of the meetings were with Knut Wiik Vollset, which should not be of any surprise, because Professor Vollset was Mari Lie’s PhD supervisor. In fact, Mari Lie was only awarded her PhD in March 2025. Her thesis was titled – Evidence based policy making: Exploring the effectiveness of salmon aquaculture management in Norway. According to FHI, Mari Lie examined whether current management systems effectively control salmon lice and protect wild salmon stocks – something that merits consideration in a different commentary. Meanwhile, it seems that despite all these experts, NASCO’s sea lice project was being directed by a PhD student.
The final report records that a paper has been prepared entitled ‘Does exposure to sea lice from aquaculture have a population-reducing effect on wild Atlantic salmon? A systematic review. The paper is to be submitted to the ‘high impact’ journal Fish and Fisheries in summer 2025. NASCO have allowed €6,500 to pay for open access fees to ‘a high-ranking journal’.
Presumably NASCO have opted for the journal Fish & Fisheries because the journal states that they amongst others publish meta-analysis.
In a final twist, NASCO reveal that to help fund the project, they applied for funding from the EU DG Mare and received 80% of the fundings of the €33,234.20 for the sea lice project of which €21,400 went towards writing the manuscript. Seemingly, the Expert Groups, various institutions would have had difficulty in covering the costs of their staff’s time.
Interestingly, I kept getting asked why I don’t write a paper, and the reasons are patently clear. However, the major obstacle is that like the Jackson paper, it doesn’t matter if the findings are clear or whether the paper is published in a high-ranking journal, if the content is contrary to the beliefs of the scientific clique, then the paper is simply ignored or portrayed as irrelevant, which is exactly what this NASCO paper will be but because of the makeup of the Expert Group and with the support of NASCO this paper will be undoubtedly portrayed a ground breaking proof of the evil nature of the salmon farming industry.
Priestly: There has been a bit of a controversy with news that a salmon farm has been suspended from the RSPCA scheme and delisted by a supermarket. This follows the publication of a video of workers despatching sick fish using a priest (a metal baton). Of course, the vegans associated with activists were outraged but they are outraged by anything to do with salmon farming.
The RSPCA standards recommend despatching sick fish with a priest as highlighted below.
Casualty slaughter
Any seriously sick or injured fish, or fish found not to be recovering, must be humanely killed without delay. Records of this must be made available on request
During the seawater stage, in addition to anaesthetic overdose, the following are permitted for the emergency killing of fish: a) a priest of appropriate size for the fish b) a mechanical percussive device.
Use of the emergency killing methods must result in a non-recoverable percussive blow to the head of the fish to render it immediately insensible.
Although the worker made repeated blows, it was unclear how many fish were in the net and even under the most rigorous control, sometimes, more than one blow is required as I am sure any angler will attest. The priest is part of any angler’s kit and is used to kill any fish that is not to be returned.
The issue is where is the line drawn. The vegan activists were outraged by one incident that they filmed but why not covertly film anglers when they use the same tool with eth same aim. Despite, salmon’s threatened status, 1,106 wild salmon were killed by anglers during the 2024 season. A further 972 sea trout met the same fate. Why is this acceptable but killing a sick salmon on a salmon pen not?
The RSPCA standard states that no fish be left to die in the air yet thousands upon thousands of marine fish die in this way. Interestingly, these and other issues about fish and pain are addressed in a new report from the Scottish Animal Welfare Commission (SAWC). According to the Scottish Daily Express, the SAWC has called on the Scottish Government to treat fish better as they have ‘emotional’ experiences that matter to them. SAWC have just published a new report titled ‘Ascribing sentience to fish: potential policy implications. This has highlighted how fish should be treated as they are caught, and this should be similar to the way birds and mammals are treated and that the Animal Health and Welfare (Scotland) Act 2006 should be amended as it currently excludes acts carried out whilst fishing.
The newspaper continues that the capacities of fish, their needs and wants may differ from terrestrial animals and may vary between different fish species but according to the SAWC, the evidence suggests that fish are individuals with personal experience as are other sentient animals.
The key recommendations in the SAWC report are that:
1) Fish caught at sea or in freshwater and therefore under the control of man should be protected from unnecessary suffering and welfare compromises.
2) Catch and release practices in game, coarse and sea angling should be given further consideration by the sport’s governing bodies and associations in consultation with fish welfare specialists.
It has always been on the cards that those screaming most about welfare issues in salmon farms would eventually have the focus turned on their own activities.