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reLAKSation no 1119

Vanishing data: Last week, Fisheries Management Scotland (FMS) published their 2023 Annual Review and did so without any fanfare.  The Annual Review is usually published at about this time of year and provides a first view of the salmon and sea trout catch statistics from approximately 45 rivers or fishery districts. The official catch statistics from Marine Scotland Science have been typically published about a month later.

I have copies of all the Annual Reviews from 2009 onwards and they provide an overview of the changing picture of salmon and sea tout catches often going back to the early 1950s so has been a valuable resource. However, I have recently begun to delve deeper into this data and observed major discrepancies between the catches reported by FMS and those that appear in the official statistics. I was looking forward to downloading the 2022 data from the 2023 Annual Review to analyse any inconsistencies in the latest data as compared to that which should be soon published by Marine Scotland Science. I was therefore extremely surprised to see that all the catch data has been omitted from this latest FMS Annual Review.

In his introduction, FMS’s Chairman provides the following explanation:

“This year you will not find catch graphs at the end of the review. The new approach reflects the timing of publication of the official Scottish Government statistics and the real-time catch data that is now available online. The Scottish Government have also decided to publish preliminary catch statistics in March – a very positive approach in our view. We are exploring means of presenting catch graphs once the official statistics are published.”

I am totally mystified by this statement. It makes no sense. Last year, the official Marine Scotland Science statistics were not published until 1st of June, some 18 months after the fishing season first began. The publication date of 1st of June is also about five weeks later than during the period 2014 to 2019 when the Data was published around 25th April each year. This means that the official statistics are now published 8-9 weeks after the FMS Annual Review is normally published. As the chairman notes, Marine Scotland Science have published a preliminary catch data at the beginning of March, but this preliminary data is worse then useless. There is absolutely no detail except the total catch for Scotland and the number of fish caught for arbitrary east and west coast regions.  The new preliminary data is no substitute for that which has previously appeared in the FMS Annual Review.

Although proper real time data might be useful, it is clear that not every proprietor subscribes to on-line data. The main source FishPal lists just eighteen rivers or catchments and there is no way of knowing the reliability of this data, so it is also no substitute for the FMS data.

I fail to understand how replacing the Annual Review data by methods not yet identified will help understand the trends of salmon declines across Scotland. Th only reason I can think of that FMS has adopted this approach is because over the past couple of years, major discrepancies between FMS data and that provided by Marne Scotland Science, have been highlighted, despite coming from the same original sources. Perhaps, both FMS and Marine Scotland Science want to avoid having to answer any questions as to the accuracy of the data they provide. However, waiting 18 months to obtain supposedly accurate data is totally unacceptable. FMS would be screaming and shouting if the salmon farming industry was even 18 days late with their data, let alone 18 months.

In his contribution to the Annual Review, the FMS Chief Executive writes that:

“Many people are rightly concerned about the ongoing declines in our wild salmon and sea trout populations. The provisional salmon and sea trout catch statistics for 2022 have now been published and whilst there was a small increase in catches, it is clear that salmon stocks remain at a low ebb. There is no simple solution to the current situation – the pressures which salmon face are complex and multifaceted, and concerted effort is required to address these pressures in the areas that we can control.”

The Chief Executive provides clear recognition that despite a small increase in catches, the provisional catch data shows salmon stocks remain under threat and that concerted effort is required to address any pressures affecting stocks. It is therefore nonsensical that FMS have delayed publication of more specific data so there can be a better understanding of what action is required to help safeguard salmon’s long term future. Of course, FMS already have preconceived ideas of those pressures that they want to control – salmon farming being one. Yet, the provisional data shows that west coast catches actually increased from 2021 and 2022. How can this be when FMS claim that management of salmon farms has failed to protect wild fish? Perhaps if the FMS chief executive or their Marine Scotland funded Aquaculture Interactions Manager would be willing to speak to me, I would happily explain to them why their narrative about the impacts of sea lice on wild fish is just wrong and their attention should focus instead on other pressures.

Meanwhile, the Chief Executive says that “concerted effort is required to address these pressures in areas that we can control” yet fails to address the one pressure that he and his members can control – exploitation. It is not just the unnecessary killing of any wild fish that needs to be stopped but the length of the fishing season should be curtailed, and mandatory training imposed on all anglers for minimal impact catch and release. Of course, we should not forget that there should be also improved up-to-date reporting of catches. The reason why Marine Scotland Science can only publish preliminary results in March, five months after the fishing season ended is because FMS members have failed to promptly submit the catch returns to Marine Scotland Science delaying early publication.


Misunderstanding data: One possible reason why FMS and MSS have delayed publishing catch data could be that they wish to reconcile their data sets before others highlight the obvious inconsistencies. Publishing any data can also lead to its misinterpretation or a misunderstanding of the implications. According to Undercurrent News, Wild Fish have just published a new report – “Breaching the Limits” in which they accuse the salmon farming industry of failing to safeguard wild fish stocks.

Salmon Scotland has refuted Wild Fish claims claiming it is ‘yet more conjecture from a group of anti-salmon activists with a long history of misrepresenting the facts’. However, it is not just the facts that are wrong but also their science. The report includes 27 references which are a mixture of scientific papers, newspaper articles and Government reports. Here I just want to focus on the science.

Most of the references are taken directly from the contentious Marine Scotland Science on-line review – Impacts of sea lice from fish farms on wild Scottish salmon and sea trout. It is contentious because MSS steadfastly refuse to discuss the science it cites and have done since it was first published around 2016. I have argued that if MSS are confident about this science, they should have no problem discussing its relevance. I would also argue that Wild Fish has simply lifted the science from the MSS review without any checks. For example, they cite Butler and Watt (2003) and give the reference as Pest Management Science 58 595-608, as do MSS. This is not the correct reference for that paper. Wild Fish also cite a paper by Butler (2002) and give the same reference – Pest Management Science 58 595-608, which is correct for this paper. If simple references are incorrect, how can any of the content be trusted?

The report begins with an introduction in which most of the scientific works are cited. One which is of most interest is actually cited twice in the references (why?) and this is by Mark Costello bout the ecology of sea lice and appeared in Trends in Parasitology in 2006. Referring to this paper, Wild Fish say that free floating juvenile lice travel as far as 70km in search of a host. The problem is that Dr Costello actually cites other work about the distances covered which are modelling studies, and not the result of actual measurements. What is more interesting is that this paper then refers to studies of the dispersal of other marine organisms such as sea grass and decapod crustaceans and assumes a similarity with sea lice.

There is a fundamental problem though in comparing dispersal by wind and currents to find a new habitat and supposed similar dispersal to find a new host. Habitat location is very generalised whereas parasite host location is extremely specialised.  Costello even recognises that parasites are distributed differently to other animals, but this is ignored because it doesn’t fit the accepted narrative. Wild Fish also ignore this aspect of the science because it would undermine the rest of their report.

Wild Fish cite a paper also from the MSS review in which they say it can take as little as 0.2 sea lice per gram to kill a n Atlantic salmon smolt. This is a laboratory experiment in which mortality occurred in both the experimental tanks and the controls. Yet the mortality of the control fish was ignored even though the lice infestation could have masked the same causes of mortality in the experimental fish. This trial should have been scrapped and restarted but it wasn’t.

When the detail of the scientific papers is explored, there are many questions arising that question the conclusions drawn. If they wish to analyse the data, then they should ensure that there is really good science to support their findings. Sadly, this is not the case with most sea lice research.  So intent they are at trying to highlight alleged deficiencies in the farming process that they just ignore the science.

If Wild Fish want to ensure the protection of wild salmon and sea trout, then they need to stop blaming others and start to talk, something they appear extremely reluctant to do.

One recent example of this unwillingness to discuss the issues face to face occurred last month at a meeting about the Icelandic salmon farming industry. This took place at the end of March in London, and anyone interested in finding out more should read a commentary that I am writing for inclusion in a future issue of Fish Farmer magazine.

One of the attendees, who posed a question, identified himself as William Hicks, Chairman of Wild Fish. After the meeting I introduced myself to him and asked why it is that no-one from Wild Fish will speak to anyone from the salmon farming industry. He replied that I should speak to someone else in the organisation to which I responded that they don’t speak either, at which point he just walked off. I find it surprising that someone who is a barrister and is so eloquent in speaking in his day job and who is clearly sufficiently interested in hearing about the salmon farming industry in Iceland, was so unwilling to discuss the industry in Scotland.


Barriers: The Herald newspaper has published am extensive expose of the failure to address the slow pace of barriers removal from Scottish rivers and the way that these barriers are contributing to the demise of wild salmon stocks. The latest River Basin Management plan dated 2021 identified 244 artificial barriers to fish migration of which just 16 have so far been removed or eased. The plan commits to remove all these barriers by 2027.

According to the Herald, Environmental Standards Scotland (ESS) are now investigating why the pace of removal is so slow especially since alarm bells are now ringing for salmon, a species already in crisis that has seen a 70% decline in the last 25 years. Some claim that the body charged with barrier removal are showing a lack of urgency and are failing to carry out their responsibilities to even ensure that all barriers over a metre tall are actually licenced.

The organisation charged with fixing the issue of barriers by 2027 is the Scottish Environment  Protection Agency (SEPA), the same organisation who are attempting to launch the risk assessed sea lice framework on salmon farming.

It seems incredible that SEPA are rushing to impose the sea lice risk framework on salmon farming with undue haste, in order to supposedly protect wild salmon, yet are perceived as having a lack of urgency when it comes to removing barriers to protect the same fish. The recent assessment of pressures by MSS and FMS show that barriers have a much greater impact on wild fish than sea lice across all of Scotland.

Perhaps SEPA need to engage in more discussion about the risk assessed framework and much more action with regard to barriers if they really want to help the recovery of wild salmon stocks. Currently it seems that they are diverting resources in the wrong direction to the detriment of all Scottish wild salmon stocks.