Excuse the language: The Norwegian salmon farming industry is well and truly stuffed This is the only conclusion I can draw from the proposals in the Norwegian government’s new white paper.
The Minister has said that although salmon is Norway’s second largest export, it can no longer be regulated as to how much is produced but how production affects the environment fish health and welfare. However, what the Minister fails to appreciate is that it is government policy that has led to poor reputation, poor fish health and poor fish welfare. Changing how the regulation is applied will not help improve the environment, fish health or welfare or reduce mortality. What it will do is further damage the salmon farming industry in Norway without achieving the positive results the government wants to achieve.
The simple reason why the plans will not work is because the government has relied far too heavily on advice from a small group of scientists. The Minister has said that she hopes that the planned changes will be fully in place by 2027 which should allow plenty of time to examine whether the scientific advice the Minister has received is correct. There should be absolutely no reason why any discussion of the science cannot be run in parallel with the implementation of the plans. I would imagine that the scientific community would claim that the science is correct but if they are confident- it is, then they should have no problem facing others who wish to discuss an alternative view.
The Minister’s speech launching the white paper was accompanied by a press release. This was reported in various sections of the media both in Norwegian and English. I was interested in one interpretation in Fish Farmer magazine which discussed sea lice quotas saying that quota levels will be set based on the carrying capacity of the natural environment. When I translated the press release, this said ‘The quotas will be set on the basis of what nature can actually tolerate in a given area.’ I take carrying capacity to be the same as what nature can tolerate.
This is an interesting interpretation of sea lice ecology. The definition of the natural carrying capacity of an environment refers to the maximum population size of a biological species that the environment can sustainably support give the availability of resources like food, habitat and water. It essentially defines the limit on how many individuals can live in a specific area without depleting or degrading the environment.
In essence, this all seems a perfectly reasonable expectation from the Norwegian government, however there is a problem. Parasites do not inhabit the natural environment as the government, or their scientists suggest because parasites do not inhabit the natural environment but instead their environment is their host. Carrying capacity of parasites of a host refers to the maximum number of parasites an individual host can support dependent on the hosts’ ability to tolerate the infection. The carrying capacity is affected by host size, metabolism and immune response.
Even if the government’s idea of carrying capacity was applied, the fact is that when considering wild salmon, the hosts do not inhabit the environment at all. They simply use the fjords to transit from freshwater to their northern feeding grounds. Fish are travelling through the water column so the imagined carrying capacity is changing all the time and only for a few weeks in the year.
Sea trout are also affected but whilst the fish do not migrate like salmon, they too are also moving affecting any perceived carrying capacity. The reality is that even if salmon farms were pumping out billions upon billions of sea lice larvae (which they are not) unless they encounter an infective sea lice larva, they will not be infested. It is also important to understand that sea lice are a natural parasite of wild fish and thus there is always a natural population of the parasite in the fjords. Sea lice infestations are not exclusive to salmon farms. In fact, whilst the focus of sea lice is directed at farming, there is no understanding of how sea lice propagate and find their host when there are no salmon farms present. Without this understanding of the natural life of sea lice, any beliefs about the impacts of sea lice associated with salmon farms are not proven. It is worth mentioning that in UK waters, there are 50 different species of Lepeophtheirus parasite infesting different species of fish. Very little is known how these parasites breed and find their host fish. What is clear is that because there are relatively so few parasites, what they don’t do is release their larvae into the open sea with a hope that they will encounter a new host fish.
When it comes to infestation of wild fish by sea lice associated with salmon farms, the scientists offer the following from the Sea Lice Expert Group’s ‘Production area-based assessment of sea lice induced wild fish mortality.’ The following is taken directly from section 3.5.1 which is a description of the Institute of Marine Research’s Sea lice dispersal model:
The particle dispersion model uses reported data on the number of lice, the number of fish and sea temperature from all reporting farms to calculate the release (number) of newly hatched larvae from the farms. These larvae experience temperature, salinity and current from the hydrodynamic model at the position they are in. Based on available knowledge about the development rate, behaviour and mortality of sea lice, it is calculated how the larvae spread with the current, first as non-infectious nauplii and then as infectious copepodites. The end product is the distribution of infectious copepodites in the fjords and along the entire coast hour by hour, which provides a good and detailed overview of which areas have a lot or a little sea lice larvae at any given time. The copepodite density maps (as below) show great spatial variation, with a clear tendency to accumulate along the shore, and in fronts and eddies. There is also a sharp increase in lice throughout the spring/summer in the most POs. The amount of infection that wild fish are exposed to will depend on the number of sea lice larvae in the area.
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(This text and image are taken from the 2023 version as in 2024 the Expert Group divided some of this detail between the main report and the appendices). The image shows the prediction of lice dispersal on 14th May 2023. The areas shown in yellow are predicted to have high lice counts in the water body.
This model is then used to predict the risk to wild fish in the area and then has been used to ascribe which colour from the Traffic Light assessment is given to the relevant PO which in this case was PO 2.
Over recent years I have raised questions about the impact of these predicted sea lice larvae on wild fish, one of which I will ask again here. As I have commented on several times previously, the relevant scientists, not just in Norway, have been extremely reluctant to enter into any form of discussion about this question.
The area in yellow is supposed to have a high concentration of sea lice larvae in the water body. The concentrations will change on a daily basis depending on wind and current, but this snapshot of a large yellow area is not unique to that day, so the question is whether the scientists have ever validated their model to ensure that it is true representation of sea lice larvae concentration by sampling the area and actually counting the lice. This model is fundamental to the regulation of the salmon farming industry that it is essential that it is reflects what is happening in the fjords. If the lice are not present as predicted, then the salmon farming industry is being unfairly accused of something which is not happening.
My understanding is that the Norwegian scientists have never validated their sea lice dispersal models by comparing the predicted sea lice concentration with the actual concentration of sea lice found in the water body.
Models are widely used in the modern world, and it is important that they are validated to ensure their accuracy. It is clear from the Covid models that they were not as reliable as was thought and this was because circumstance prevented proper validation. A summary of why validation is so important is as follows:
Validating predictive models is crucial because it ensures their accuracy, reliability, and generalizability when applied to new or different data. Validation helps identify potential overfitting, underfitting, or biases, which can lead to inaccurate predictions and unreliable decision-making. It’s a key step in ensuring that a model performs as intended and can be used with confidence in real-world applications.
It is my understanding that sea lice scientists will claim that the models have been validated, not by sampling actual lice larvae but by using sentinel cages. Unfortunately, whilst scientists claim sentinel cages are an effective way to validate their models, the reality is that any infestation of sentinel cage fish could equally come form passing wild fish. I am led to believe that no-one has actually determined how the fish become infested. What I do know is that between 2011 and 2013, Scottish government scientists operated several sentinel cages in Loch Linnhe and during the smolt migration period, not one sentinel cage suffered anything but the lowest levels of sea lice infection, yet somehow the results were used to validate the Scottish sea lice dispersal model. As a note, during the autumn period, the sea lice level in the same sentinel cages were much higher, which coincided with the appearance of returning adult salmon most of which were infested with sea lice. Rather strangely, the Scottish scientists have refused all attempts to discuss the role of sentinel cages in model validation.
The Traffic Light system has been in place since 2016 which has given scientists many opportunities over nearly a decade to sample for sea lice in the water body. It is only necessary to trawl up and down the fjord in the affected area with a plankton net and then separate out the sea lice larvae, yet it has not happened. Given that such simple science is all that is required to ensure that any regulation is appropriate, the fact that this has not happened is highly questionable.
Of course, those of us who are immersed in sea lice science know that whilst the idea of trawling for sea lice larvae with a plankton net should be a relatively simple process, the reality is very different. This is because researchers from around the world have been looking for sea lice larvae in the water column since 1994 and have yet to find any. If the infective sea lice larvae are not present as the models predict, then they cannot represent any risk to wild fish. Yet, in their narrative about sea lice and salmon farming, the scientific community do not seem to consider this a problem. It is just a minor inconvenience, especially if no-one ever challenges them and other than me who does?
The hunt for sea lice larvae has taken place in most fish farming countries including Norway. Karin Boxaspen is the head of the Sea Lice Steering Group but in 1997, she published a paper about the variation in abundance of salmon lice, the abstract of which begins:
Surveys in the area around Austevoll Aquaculture Research station have failed to reveal the presence of a large number of free-swimming stages of salmon lice in the water column.
I think that is clear as to the fact that after nearly thirty years, lice could not be detected around salmon farming facilities. Although I don’t usually discuss my correspondence, but a very rare exchange with Dr Boxaspen in May 2023 is worth repeating here bearing in mind her role in providing sea lice advice to government and how important getting the science right is to the future viability of the salmon farming industry.
From: Boxaspen, Karin Kroon
Sent: 31 May 2023 15:05
To: Martin Jaffa
Subject: RE: Not surprised
HI Martin, sorry for the delay but discussions of effects of sea lice on email is not very high on my list. It would take all my time and are not really within the scope of my job.
Thank you for the article. The article addresses issues we discuss within our oceanography research group on a regular basis. They have also found the article very interesting and correct. They might read it differently than you? I also find that the word “model” is used very widely and misused for all kind of things. IMR has been developing and are using hydrodynamic models for decades. It is used for describing dispersion in the sea be it fish eggs, plankton (sea lice), inert particles from mining waste and even under search for drowned people. That they replicate the currents and physical measurable parameters like salinity and temperature have been well documented.
I find that a lot of people seem to think that the problems with sea lice/ salmon lice must be the same everywhere in the world. That Norway with long fjords giving a long migratory route to the sea for the post smolts and a production of about 1,3 mill metric tons salmon produced per year in the same area are automatic comparable to other places seems at best misguided.
We have been through two court cases where the science for the effects of salmon lice on wild salmonids stood up very well. The fish farmers lost in both levels of court and their appeal was not taken up by the Supreme court.
We will continue to publish all of our findings and share how the models are run so that others can check our work.
Best regards
Karin
Despite the fact that this critically important issue is not on her list of priorities, the actual issue is not about the model but how it is applied to a parasite, which behaves totally differently to either other plankton, mining waste or even drowned people.
The last major attempt to identify sea lice in the water body took place in Scotland during the summer of 2021. Scottish researchers sampled an area around the Isle of Shuna off Scotland’s west coast, which is home to ten fish farms. Over seven months, they sampled 372 times and found just twenty lice. Like in Norway, these Scottish researchers had the benefit of a sea lice dispersal model showing where high densities of lice larvae were predicted, yet they still only found twenty lice larvae (one was actually an adult). The final report stated that just because they couldn’t find any lice doesn’t mean that they are not there.
This is a statement from scientists who cannot let go of the fact that whole narrative about sea lice is simply wrong.
I have written previously about why it is wrong and the answer s available in a paper published in 1996 that has been widely ignored because it doesn’t ft the accepted narrative. I have spoken to one of the original researchers and he said that at the time of publication, they received a great deal of abuse from those who thought that their work was intended to shift the blame for declining wild fish numbers away from the salmon farming industry. We now know that salmon farming does not have the claimed effect on wild fish numbers as claimed, although the scientific community still seem reluctant to accept this fact. The 1996 paper showed that any sea lice emanating from a salmon farm was so dilute within 1 km of the farm that they were impossible to detect. They still remain almost impossible to detect and that is because they are still so dilute in the water body. Clearly, if the sea lice are so few in number in the water body, they cannot represent a risk to wild salmon.
In a report published alongside the white paper from the Fish Directorate, the Food Safety Authority and the Environment Department, which is their response to an assignment to investigate the instruments for sea lice regulation, the same process and science as used in the Traffic Light System will be used for the new sea lice quota system. This will make the new quota system as equally flawed as the Traffic Lights.
I began by expressing my view on the impacts of the white paper on the salmon farming industry in Norway. The industry has now got at least a year to demand a full reassessment of the science to make sure that the new regulation is not only valid, but that it will actually serve the intended purpose. If the industry does not demand such a discussion, then they will have no-one but themselves to blame when they find they have been well and truly stuffed.