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reLAKSation no 1091

Summarised: The Summary of Sea Lice Science posted on the Scottish Government website continues to offer endless opportunities for further investigation. One of the references cited in the summary is a paper by Butler and Watt (2003) however, as I have pointed out more than once before, the reference provided is incorrect. I would have thought that prior to posting on an official website, everything would have been double checked but apparently not.

The reference as it still appears on the website is shown below:

However, the paper that has been published in Pest Management Science is not the one cited but another paper by James Butler in his name alone and is titled ‘Sea louse infestations on the west coast of Scotland.’ This is a much more interesting paper by far than the one cited, because it includes what I consider to be the first graphical examples of aggregated sea lice infestation, and this is in a paper that was published twenty years ago.  The graphs grouped the lice together in bundles of twenty lice so one to twenty lice, twenty-one to forty lice and so on. This does not provide sufficient clarity on the spread of the lice although it is clear that the majority of fish have low lice infestations. Butler used a figure of thirty lice per fish as the number of lice that might be potential lethal, and he claims that fish with levels above this, range from 14% to 40% of the sample but this is difficult to ascertain from his graphs.

Butler obtained his data from that collected by the west coast fisheries’ trusts for the month of June for the years 1998 to 2000. Fortunately, these three years are included in the data published earlier this year by Marine Scotland Science for the years 1997 to 2019. This means the data should be available for me to reproduce these graphs but in greater detail.

Unfortunately, whilst James Butler has given the size of the samples collected during the month of June as:

1998 – 232

1999 – 156

2000 – 205

The Marine Scotland data base has only the following number of entries:

1998 – 85

1999 – 101

2000 – 139

This represents a shortfall of 147, 55, and 66 samples that appear to be missing from the Marine Scotland database. Because of the way that Butler drew his graph, it is only possible to look at the lice free fish to assess the difference. For 1998, Butler shows about 21% lice free fish whereas the Marine Scotland data base records just 10%.

For 1999, Butler records about 48% lice free fish whereas MS have just 25% of the fish as lice free and finally for the year 2000, Butler has 24% of the fish free of lice, whilst MS have just 13% lice free. Clearly, a large proportion of the missing fish samples are fish that are lice free.

This discrepancy of 325 fish samples from just one month over three years brings into question the accuracy of the remaining data in the full Marine Scotland dataset. How many other samples are missing and are these samples free of lice or with very low lice numbers? The obvious reason for raising this question is that some of this data has appeared in published papers that are cited in the Scottish Government’s summary of science as demonstrating that salmon farming has an impact on wild fish. If the data is incomplete, then any resulting conclusions could well be flawed.

This would not be the first time that results of sea lice monitoring have been misreported in official Government datasets. In 1996, the Irish Sea Trout Monitoring and Advisory Group (STMAG) raised concerns about discrepancies in the sampling procedures and data collation of sea lice monitoring in Ireland. They decided to commission an independent review and consequently, an academic from the University of Hull in England was commissioned to undertake this task. The findings were that there were discrepancies in the monitoring programme with errors of up to 14%. Part of the problem was that despite best intentions, in order to get samples from a wide range of sites, the monitoring programme was too dissipated, which also could be said to apply to Scotland.

In addition, the Scottish monitoring programme is operated by Fisheries Trusts who are ultimately part of the wild fish sector and who, it could be said, have a vested interest in the results. Perhaps, the monitoring programme should be undertaken by an independent agency, if such a monitoring programme is even necessary.


Inaccurate: The possibility that inaccuracies exist in the sea lice monitoring programme reminds me that questions about the accuracy of the annual catch data have been totally ignored. I have previously written that the catch numbers published in the latest issue of the Fisheries Management Scotland (FMS) annual review do not tally with those listed in the Marine Scotland Science official catch data.

One explanation is that sometimes official data is deficient of catch data because some proprietors have been tardy in submitting their returns (Why? and why are they not taken to task over such delays lasting a period of months?) and that the numbers will be adjusted when the statistics are reissued. However, the FMS review is always published before the official statistics so if they have the numbers, why cannot MSS have them too.

Whilst the 2021 catch data may not be reconciled yet, the catch data from previous years should now have been. I have therefore looked back at all the years in which FMS have reported catches in their annual review. This is for catches from 2011 to 2021.

As there are about forty records for each year to examine, I have taken the data from five rivers for comparison. These are the Tweed, Tay, Ythan, Deveron, and Spey, all of which are east coast rivers.

Before I discuss the findings, I would mention that having sampled some of the data that some fishery districts consistently report the same number of fish caught as MSS and there are also examples where the fishery district total is less than the subsequent MSS total.

However, as can be seen from the following table, in every year but one, the number of fish reported in the FMS annual review exceeds the numbers that appear in the official statistics. In some years, the numbers can be small for these five districts with the lowest being 87 (2016) although the year later produced the only negative figure with MSS catches exceeding those in the FMS report.

The largest differences appeared in 2012 and 2020 with differences well over two thousand fish.

Given that FMS has called for action to protect wild salmon, it is nothing short of a national scandal that FMS and MSS cannot agree on how many fish are caught every year. The catch data is important in assessing the state of the total population as well as future egg output. Inaccurate data can only lead to inaccurate conclusions.

However, the biggest scandal at all is that no-one from Marine Scotland nor the wild fish sector appears interested in the fact that there is such a divergence in catch numbers. Anyone interested in the well-being of wild salmon populations should be concerned but instead there is silence.

Later in this issue of reLAKSation I mention that the Coastal Communities Network wanted representation on the Scottish Aquaculture Council. One group which does attend is FMS. I wonder whether the interests of wild salmon would be better served if they spent all their time getting their own house in order rather than continuing to spend their time attacking the salmon farming industry.


Whose voice:  The Coastal Communities Network (CCN) recently sent out their newsletter with the news that following their meeting with the Cabinet Secretary & Minister for the Environment and Land Reform, CCN’s request to be part of the Scottish Aquaculture Council was denied and rightly so. The disparate group made up largely from what Professor Griggs described as the economically inactive part of the community have no mandate to speak as community representatives. They have made it clear that they are very much against the salmon farming industry and all that means with regard to job creation and boosting local economies. The problem is that it seems that anyone can form a group with the name community in it to give the impression that they represent something they actually don’t. CCN reminds me of the Salmon & Trout Association, an organisation that greenwashed its name by replacing ‘association’ with ‘conservation’. However, just because they included the word ‘conservation’ in their name doesn’t make them conservationists. They have since changed their name again to Wild Fish Conservation but still have yet to call for an end to killing of wild salmon and trout for sport.

After being denied membership of the Scottish Aquaculture Council, CNN have written that this means that: ‘there is currently no organisation representing the community impact of the industry in this group’ or do they really mean that there is no organisation representing the community interest relating to the impacts of the industry. Unfortunately, CCN simply follow the herd of other industry critics by repeating the same old criticisms but remaining uninterested in discussing these impacts unless any discussions agree with their existing views.

Interestingly, for a network supposedly about coastal communities, CCN is run from Edinburgh by Flora & Fauna International, a conservation organisation who say that they have been quietly shaping and influencing conservation practice since 1903. It seems that CCN is not about coastal communities at all but using them to influence conservation policy so whilst CCN criticise salmon farming for allegedly having an impact on the environment, but with little proof, they have yet to openly criticise the angling sector for killing fish for sport. In fact, to the contrary, Friends of Loch Hourn use data on the number of fish killed by angling as evidence of the alleged impacts of salmon farming.

Friends of Loch Hourn are an interesting example of the groups that form CCN. Although they will not admit it, they were established to specifically object to changes to salmon farming development in Loch Hourn. Despite being established in 2020, other areas of their website than those about salmon farming are still under development. The group says that they have over 100 members but there is not a single person who appears willing to put their name to being with the group.

The latest CCN newsletter also brings news that the group Friends of Loch Creran has disbanded. This was an example of a ‘group’ whose only interest was fighting against salmon farming and to the best of my knowledge comprised of just two people, who also were a couple. They had moved into the area and were horrified to find that there was a local economy providing people with work and an income.

Coastal Communities Network submitted a seventeen-page response to the SEPA consultation. This is far too long for comment here, however there are a couple of points worth mentioning. The first is a statement to ‘be precautionary while more information is gathered’. They say that ‘in a situation of seriously deficient knowledge it is vital that SEPA take a precautionary approach’. That is their view. I am of the view that there is plenty of knowledge available but because it is not the knowledge that CNN (and others) want to hear, they claim the knowledge to be deficient. I have previously mentioned that I offered to speak to CCN’s aquaculture group about some of the latest sea lice knowledge, but they refused.

The second point is the last paragraph. CCN state that ‘it is their hope and expectation that CCN will be part of the implementation group for the new framework, particularly as it has significant expertise in sea lice modelling’. Personally, I think we already have far too much modelling and not enough fact. Just as with the Scottish Aquaculture Council, CCN do not have a mandate to speak on behalf of the communities and my hope and expectation would be that their hope and expectation should be denied.

In their consultation, SEPA asked respondents if they have any expertise they wished to share, and CNN said yes. They explain that several members of CCN have worked with the hydrodynamic modelling company MTS-CFD to develop sea lice models such as in Loch Hourn.  They say they are now working on a wider area model and are also liaising with Marine Scotland Science SPILLS team. (Yet when asked, MSS have said that they have no knowledge of this liaison). They continue that they have a good understanding of the underlying biological science and use of integrated biological models including the most widely used protocols and parameters for se lice behaviour (although their response to SEPA doesn’t provide much indication of such understanding). They also say they are well versed in the important issue of how the results of this modelling should be analysed and presented to help decision makers and communities understand them (in other words, how to twist the science and develop a narrative that portrays the salmon farming industry in the worst possible light).

The salmon farming industry already faces a large number of ‘experts’ whose only qualification seems to be catching fish for sport. Now it seems that living by the coast is also sufficient qualification to be an expert too.