Scottish affairs: The Scottish Parliamentary debate of the Rural Affairs Committee inquiry into salmon farming took place on Thursday, which I will discuss in the next issue of reLAKSation. I will also comment then on the announcement by the Cabinet Secretary that she intendeds to leave politics.
Two and two: According to iLAKS, CEO, Robert Eriksson of the Norwegian Seafood Industry Association has said that the Traffic Light System has not worked. His view is supported by the Aquaculture Committee’s report from autumn 2023 which said that several rounds of reductions have not led to better conditions for wild salmon, despite a high cost to the industry, The reduced production has been perceived as poorly targeted and appear as rather arbitrary measures. In addition, research from, among others, the Institute of Marine Research (IMR) supports this conclusion.
The news that IMR do not believe the Traffic Light System to have worked highlights the fact that sea lice scientists are simply out of touch. On one hand, their research is said to show that the Traffic Lights do not work yet, their recent Risk Report incriminates salmon farming in the decline of wild salmon. They appear unable to put two and two together and concluded that the reason the Traffic Light System does not work is because, despite their claims, salmon farming is not the cause of the continued decline of wild salmon.
Mr Eriksson says that the Traffic Light System has not been successful in solving the real challenges of the aquaculture industry, neither in terms of sea lice nor increased salmon production, He says that the authorities must stop prescribing more of the medicine (as in the Traffic Light System) that does not work. Instead, he says we need new and better tools in the toolbox.
I would disagree with Mr Erisksson. We may need new and better tools but that is not what is needed now. What is urgently required is a new discussion about the impacts that the industry is alleged to inflict on the environment. I have written before now that the new green technology etc that is regularly promoted as solutions are not a solution at all because the problem that they are supposed to address does not actually exist.
Mr Eriksson is spurred on to highlight the deficiencies created by the Traffic Light System because not all farming companies are treated equally. However, I would argue instead that the fundamental problem is that the Traffic Light System relies only on the ‘expertise’ of a small clique of scientists who refuse to even consider that the science they advocate may be wrong. It is sheer madness that an industry that is at the mercy of this clique of scientists has no representation on the Sea Lice Expert Group or its Steering Committee. Surely, the industry has a greater level of expertise than many of these scientists who are more interested in the publication of peer reviewed papers than the success of one of Norway’s most important sectors.
I am still waiting for any of these expert scientists to explain how catches of wild salmon from Scottish rivers around salmon farms are declining at exactly the same rate as catches of wild salmon from rivers where there are no salmon farms, if sea lice are responsible for the decline. In fact, I would invite readers of reLAKSation to write in with any other possible explanation to why catches from two different coasts are in decline at exactly the same rate.
Real data: Kyst.no has published a commentary from Even Søfteland of PO3/4 Knowledge Incubator in which he details some of the new information that has increased our knowledge of the interactions between salmon farming and wild fish. He specifically highlights the data from the Granvin River at the end of the Hardangerfjord in Vestland County.
First Mr Søfteland discusses how data is collected by both IMR and the industry led Salmon Tracking 2030 programme (ST2030), IMR have been monitoring migrating smolts since the late 1990s through the NALO monitoring programme. The monitoring programme lasts for around 4 weeks in the spring (although in some places, it lasts a little longer).
Since 2017, ST2030 began a programme of monitoring rivers which now covers 50 different rivers in total. The various ways rivers are monitored is by video surveillance and a variety of fish tags.
In 2017, the Norwegian Government established their Traffoc Light System to regulate growth in salmon farming based on the risk to wild fish. The TLS is based on 4 physical methods of measurement and 4 different models. Mr Søfteland highlights that the TLS relies on an Expert Group made up from scientists and a Steering Group also made up from just scientists.
Mr Søfteland goes on to consider the data collected from the different sources. He says that in the spring of 2022, the NALO trawl caught a total of nine (9) salmon smolts that were thought to originate in the Granvin River. These fish had 0.059 lice/gram of body weight which was well below the 0.3 lice/gram which the researchers claim will lead to the deaths of all 9 fish.
The nine fish were not caught together but as follows, with 4 fish caught 10-12 May, 2 from 17 May and 3 from 20-22 May. IMR also conducted other trawls where no fish were caught. Mr Søfteland makes no mention of the small nature of the sample size but 9 fish especially caught over three different samplings can hardly be considered representative of the wild fish population. In Scotland, the protocol for sampling fish is for a minimum sample size of 30 fish, although the success of achieving this size of sample is only 18% with 72% being of a much smaller size. In Norway, Taranger recommended a minimum sample size of 100 fish but this number has been conveniently forgotten by IMR because it is so hard to achieve. Instead, they rely on sample sizes that are so small, they are actually meaningless. In the one short conversation that I have managed to have with IMR they argued that small samples are acceptable. However, I would argue that one sample of 30 fish is not the same as 30 fish caught one at a time in 30 different samplings. IMR also appear to ignore the fact that parasites are not distributed evenly through a host population and that it is perfectly natural for a small number of fish to have high lice counts. It is also easier to catch fish which are parasitically challenged than it is to catch healthy parasite free fish. The fact that decisions are being made on a catch of just nine fish is just one of the weakness’s of the Traffic Light System that should be questioned.
In addition to trawling, IMR set up sentinel cages throughout the Hardangerfjord, and at the same time period when the Granvin fish were being trawled, from 12-26 May, all the sentinel fish were classified as green which indicates that they were not suffering any lice infestation. During the second period from 25 May to 9 June, half the sentinel cages were classified as yellow which still indicated a very low level of lice infestation.
The ST2030 programme used tags and video surveillance to identify that the smolt migration had begun in early April and by 22 May 75% of the smolts had left the Granvin River by which time IMR had also completed the NALO trawling in the locality.
Based on the 9 fish, the IMR modelling of mortality calculated that around 50% of the smolts died on their migration from sea lice infestation despite having an average count of 0.059 lice/gram. By comparison, the Etnevassdraget which is at almost the end of the fjord had an average lice count of 0.22 lice/gram but were modelled as having a mortality of just 23.7%. Finally, fish from the Uskedalselva river which is located much in the middle part of the fjord had lice counts of 0.66 lice gram but were modelled to have a mortality of 35.5%. Both the Uskedal and the Granvin river are classified as red in the Traffic Light System whilst the Etne was classified as yellow. This makes very little sense.
Mr Søfteland suggests that when the IMR data is combined with that from Salmon Tracking 2030 the IMR modelling cannot be correct. He says that one or more assumptions for estimate mortality in the Traffic Light System must be inaccurate or at worst, wrong. He adds that given the many billions spent every year on measures to reduce the impact of salmon farming on wild fish, it is important to ensure that the measures are both effective and measurable. Inaccuracies and incorrect conclusions are an obstacle to any attempts to improve conditions for wild salmon and sea trout. He ends by saying ‘It can’t be like this’.
I would go further and say that whilst the modelling is still finger in the air, the basic science is also wrong. The Expert Group say that infective sea lice are transported down the fjords infecting any wild fish they encounter but as yet, none of these scientists have shown that these modelled sea lice larvae can actually be found in the fjords. It is not enough to use a model to predict their presence, the time has come to prove their existence in the waters. Surely after 30 years of attempting to show their presence, the time has come to prove it or change the narrative.
Lowered threshold: About a month ago, a commentary was published in Intrafish written by Nina Santi, Managing Director of INAQ that proposed the imposition of a lower lice limit on farmed salmon until week 30. I am prompted to write about this commentary now after Aquablogg published a commentary about her proposal. Aquablogg goes into detail about the numbers used by Dr Santi which I don’t intend to repeat here. What I found of more interest is the approach she takes that appears to treat sea lice as a theoretical product rather than a living parasite. What is of most concern is that Dr Santi expounded her views at this year’s lice conference when as Even Søfteland has shown, there are much more important issues that require urgent discussion but never reach the agenda.
Dr Santi says that previously she has argued that the focus needs to be on reducing the production of sea lice on farms although critically, she doesn’t say why sea lice numbers need to be reduced.
In her latest commentary she says that lice prevention and control is complex and when trying to solve such complex issues there are some tools that can be useful, which to her knowledge have not been used to contribute to lice control.
The tool to which she refers is a scientific field called ‘systems thinking’, which is an approach to analysing system complexity primarily to understand how the dynamics of the systems might be changed but also allows the further development of models and scenarios. Dr Santi says that this approach has found application in many different fields including environmental protection and ecology.
According to Dr Santi, systems thinking is about understanding dependencies and connections with many systems being characterised by being stable over time. This is because there are equilibrium mechanisms in the system which ensure that changes are balanced, and the situation stabilised. She says that it is important to identify such equilibrium mechanism as they function as buffers against change like a thermostat on a heating system.
Dr Santi says that by applying systems thinking to lice development, two effects emerge. One is the powerful reinforcing mechanism of lice reproduction with the potential for exponential growth. To offset this growth, Dr Santi says that there is a n equilibrium mechanism in the system – the 0.5 female lice limit set by the authorities. This she says is the thermostat in the lice system. She goes on to explain that by lowering the lice limit will bring greater stability to the lice system and will prevent sudden surges in the number of lice on farm.
Unfortunately, applying this different thinking to sea lice, ignores the overall understanding of the ‘lice system’. It doesn’t require systems thinking to know that maintaining sea lice at ultra-low levels will prevent the development of high numbers of sea lice on farmed salmon. However, if this approach is applied to traditional salmon farming the inevitable outcome will be high levels of stress from repeated treatments, leading to ever higher levels of mortality and reduced fish growth.
More critically, this approach forgets the imposed purpose of controlling lice numbers which according to the scientific community will protect and safeguard stocks of wild salmon. Sadly, this narrative continues to dictate policy even though it is clear that maintaining low levels of lice on farm does not safeguard wild fish simply because the reason that wild fish numbers are in decline has nothing to do with sea lice or salmon farming. Dr Santi also ignores the fact that sea lice are a natural parasite that are part of the aquatic system and restricting sea lice on farmed salmon does not necessarily restrict sea lice in the environment.
We don’t need systems thinking for sea lice management. What we do need is a new no-nonsense discussion on the interactions between salmon farming, sea lice and wild fish. We can then understand what measures are actually required for the control of sea lice on farms if any. Perhaps, what is needed is just the routine management by healthcare professionals rather than government regulation.