Introgression: The Norwegian website, Aquablogg, highlights an updated report from the Norwegian Institute for Nature Research (NINA) that looks at the genetic influence of farmed salmon on wild salmon stocks during 2020. In an interview with Dagens Naeringsliv, the lead author, Kjetil Hindar said that nearly three out of four national salmon rivers are impacted by farmed salmon, which means these rivers suffer from both increased mortality and lower production. According to Aquablogg, Dr Hindar says that stock from escaped farmed salmon produce fewer migrating smolts and have a higher mortality rate whilst at sea. These salmon exhibit changes to important traits such as growth rate, age at migration, migration patterns and maturation. These are all traits that are believed to weaken the way salmon adapt to the natural environment.
The study investigated 53 rivers that are classified as National Rivers in Norway. Of these 15 (28.3%) are classified as green which means that they have no genetic changes. Another 15 (28.3%) are classified as yellow with weak genetic changes. A further 10 rivers (19%) have moderate genetic changes and are classified as orange and the remaining 13 rivers (24.5%) have had major genetic changes detected and are classified as red. Since the last evaluation in 2019, eight rivers have been shown to have genetic changes that have deteriorated whilst six others have improved.
In a leaf out of my own book, the researchers at Aquablogg examined the catches of salmon from the 53 National rivers and have published their results in the following graph:
In this graph, yellow rivers are shown in black to help distinguish them from orange rivers. The green, yellow and orange lines relate to the left hand axis, whilst the smaller catch from the red rivers use the right hand axis.
The graph shows that whilst both green and yellow rivers have catches that are either stable (green) or down 15% (yellow), catches from orange rivers have increased by 17% and by 52% from red rivers. The ‘green’ river Tana is not included in this data because catches have so seriously collapsed, it would distort the overall data. The collapse of catches from the River Tana is said to be due to excessive over-fishing as a consequence of poor river management.
Aquablogg asks how is that the rivers with the highest degree of genetic change are producing the most improved catches, whilst those with little change are in decline? Aquablogg is not hopeful that the researchers from NINA will reply. Instead Aquablogg points to another study that ran from 2017 to 2019 and was funded by Fiskeri- og havbruksnæringens forskningsfinansiering (FHF).
One of the co-authors of this report was Dr Kjetil Hindar, who also co-authored the NINA report. The FHF study found that only a small number of fish that are genetically identified as coming from escaped farmed stock find their way up the rivers and successfully spawn, but crucially, that these fish have a greater similarity to wild salmon than they have to the various breeding stocks from which they originate. Despite the significance of these findings, the authors did not seem to express any opinion as to why such differences had occurred.
The conclusion expressed in Aquablogg, and one that I support, is that natural selection is weeding out the salmon that are not adapted to life in the wild. By comparison, those salmon with the best adaption to life in the wild are the ones that survive. This is contrary to the usual narrative about escaped farmed salmon which argues that maladapted fish do survive and subsequently breed increasing the maladaptation leading to, as Dr Hindar told Dagens Naeringsliv, fewer offspring and increased mortality. Seemingly, his own research does not appear to support this view. Why maladaptation would continue to be successful is a complete mystery.
Whilst red rivers have a high degree of genetic change, as expressed by the SNP analysis, the few fish that do adapt to the wild appear to help increase the size of the stock. This would suggest that genetic introgression might not be the evil that the wild fish lobby claim it to be.
Connections: Eva Thorstad, one of the prominent members of Vitenskapelig råd for Lakseforvaltning – the Scientific Council for Salmon Management, a group appointed by the Norwegian Environment Agency, has tweeted that ‘salmon farming reduces wild salmon populations.’ Her Tweet linked to a new paper by Ingrid A. Johnsen, and her colleagues, published in the ICES Journal of Marine Science.
This tweet was forwarded to me, because Eva Thorstad has blocked me on Twitter. I can’t remember why she blocked me, but it was probably for correcting or questioning what she had said in one of her tweets. If she hadn’t blocked me already, she would probably block me now. This is because I would like to point out that this paper does not show that salmon farming significantly reduces wild salmon populations at all.
Instead, I would suggest that her post should say that “a ‘virtual post smolt’ (VPS) model built by the authors suggests that salmon farming significantly reduces wild salmon populations”. As far as I can see, the paper provides no evidence at all that salmon farming has any impact on wild salmon. The nine-page paper (excluding references) uses the word ‘assumed or assuming’ 28 times. It uses variations of the word ‘estimated’ 58 times and the word ‘calculated’ 10 times. There are far too many assumptions and estimations to consider that these findings are a true reflection of what happens in the fjords.
In an attempt to build the model using actual data, the paper described how for calibration and validation purposes, wild salmon smolts were captured in the outer part of the fjords using a surface trawl 35m wide and 5m deep towed at 4-5 knots. This produced observational data of a captured wild post smolts for weeks 18-24 for the years 2015 to 2019, yet there is no mention in the paper of how many fish were caught nor whether they were infested with lice or not. Instead, the paper dwells on from which rivers fish might originate. The abstract mentions that an archive with spatiotemporal concentrations of lice larvae in Norwegian coastal water that had been established using a combination of state of the art hydrodynamic and lice biology models was used to evaluate lice influence during post smolt migration, but this is not actually mentioned in the paper. It does seem to me that this VPS model was built on the output from other models making it a model on a model. This does not instil any confidence that the findings present a realistic picture of what happens to smolts during their early migration.
What is concerning is that one of the co-authors of this paper is a member of VRL whilst two others are on the Expert Group who advise on the Traffic Light System. It begs the question as to how much influence does such modelling have on policy and whether regulation of the salmon farming industry in Norway is based on assumptions and estimates rather than on hard facts? The biggest assumption is that salmon farming does have a negative impact on wild. If researchers didn’t think this, then they wouldn’t bother building a model at all.
In a past issue of reLAKSation, I discussed that VRL have stated that sea lice are the greatest threat to wild salmon populations, even though exploitation or over-exploitation is responsible for the loss of more salmon to wild populations than the predicted, but unproven, estimate of the effects of sea lice on wild fish. Last year 136,000 salmon were killed by fishermen whilst a modelled estimate of just 39,000 salmon were predicted to die from sea lice. It is rather surprising that the loss of 136,000 wild fish is not considered a threat to the population yet, an estimated 39,000 fish predicted to die from sea lice, is.
The real problem is that experimental work involving real fish does not support the conclusions of the modelling work. Research by Dave Jackson and his colleagues at the Irish Marine Institute found that mortality due to sea lice was only about 1%. According to the Irish Marine Institute a similar study in Norway arrived at the same result. What is interesting is that one of the authors of the Norwegian work is also a co-author of the latest modelling paper as well as being a member of VRL.
What makes the Jackson paper even more interesting was that a group of four scientists from Norway, Canada and the UK, subsequently issued a short communication to the journal that published the Jackson paper claiming that Jackson and his colleagues had made three fundamental methodological errors and that sea lice exert a large effect on wild fish. One of these scientists was Bengt Finstad, who now sits on the Expert Committee and has just retired from VRL. He also co-authored a report about sea lice commissioned by Salmon & Trout Conservation that was used to attack the salmon farming industry in Scotland.
The second author was Crawford Revie, who has just been commissioned to lead a group of scientists, who will review that Traffic Light system for the Norwegian Government. The third scientist was Martin Krkosek, who first came to attention when one of his first studies on modelling sea lice impacts was questioned because it claimed that wild salmon mortality was caused by salmon farms. The reason it was questioned was because although sea lice numbers were measured on wild fish, they were not measured on the farm. Crucially, as highlighted by campaigner Vivian Krause, there wasn’t any fish on the farm during part of the study. Martin Krkosek later admitted that the study was correlative and did not show cause. Interestingly, the study was funded by the environmentalist David Suzuki who campaigned against salmon farms.
This is not the only time that Martin Krkosek has collaborated with researchers from Norway. In 2017, he was a co-author on a paper titled ‘Disentangling the role of sea lice on the marine survival of Atlantic salmon’. In all, this paper has sixteen authors, thirteen from Norway and three from Canada.
Of the Norwegians, four are currently members of the Expert Group and four are associated with VRL (two have just retired and one has just joined).
The significance of this association between scientists is that Martin Krkosek and another of the Canadian authors, Andrew Bateman are directors, along with Alexandra Morton, of the Salmon Coast Field Station. Martin Krkosek has been closely associated with Alexandra Morton for many years and has been a co-author on at least twelve papers which have included a contribution from Ms Morton.
I shouldn’t need to highlight that Ms Morton’s form of science has led to closures of salmon farms in the Broughton Archipelago and now the planned closures of farms around the Discovery Islands.
It makes one wonder how long will it be before the science and modelling behind the Traffic Light system starts to indicate that rather than reduce farm production, it should close it down?
Who’s to Blane(y)?: Canada’s National Observer reports that salmon farming company’s Mowi and Cermaq want the Federal Court to set aside the Fisheries Minister’ decision to phase out salmon farming operations in the Discovery Islands. Initially, they are seeking an injunction to suspend the decision until the court hears their application.
The Fisheries Minister had said her decision was largely the result of overwhelming opposition to the farms by the regions’ seven First Nations.
While the opinion of Indigenous Peoples is an integral part of decision making in Canada, it is not the only consideration. Most importantly the country’s Prime Minister has made it clear that First Nations do not have veto power over the Nation’s development decisions.
Justice Cohen was uncertain about the connection between salmon farming and wild salmon runs in 2012, which is why he proposed that research should be undertaken by Fisheries & Oceans Canada to determine the impacts. Eight years on, DFO concluded that farms pose minimal threat to wild salmon runs. This is something that is becoming ever more apparent in all salmon farming nations. Previous claims about the impact on wild fish have been based on circumstantial evidence that has been widely disseminated by others with a vested interest. It is right that the decision should be taken to court so that both sides can express their point of view.
What seems to have been forgotten is that there is an experiment currently underway in the Broughton’s where salmon farms have already been removed. Surely, it makes sense to see whether there is any recovery of wild salmon there, before further decisions about closures elsewhere are taken.
Bob Chamberlain, a former vice-president of the Union of BC Chiefs and long-time advocate for wild salmon has listened closely to the advice of Alexandra Morton who originally blamed sea lice and now PRV for the declines. Mr Chamberlain told the newspaper that more than 100 First Nations depend on wild salmon along the coast and this is why there is support for removal of the farms. What he doesn’t say is what will happen when the farms are gone, and the wild salmon still fail to return. He also said that the proposed closures are the result of a consultation between the Homalco and other Nations and the Minister.
Homalco Chief Darren Blaney told the National Observer that the DFO had conflicting roles as both a promoter of fish farms and a regulator tasked with protecting wild salmon. He said that the aquaculture companies never bothered to address the issues they created with sea lice and diseases adding that they never looked into closed containment on land because they had a free ride in the ocean.
Perhaps the reason why the salmon farming companies didn’t consider land-based farming as an option is because it isn’t commercially viable and even if they were forced to do so, the likelihood is that they wouldn’t do it in BC. Equally, the simple fact is that salmon farming is not the cause of the decline of wild fish and therefore there is no reason to move out of the sea and onto land.
It is interesting that Chief Blaney highlighted possible conflicts in DFO because the same might be said within the Blaney family. Seafood News reports that a west coast MP has spoken to the Fisheries Minister to relay her concerns about the repercussions of the decision to remove salmon farms from the area. She said that workers and small business owners are understandably worried for their and their family’s futures adding that a plan needed to be implemented sooner rather than later so that the economic concerns of the region are addressed.
It’s a shame that this North Island-Powell River MP, Rachel Blaney, who is also the wife of Chief Darren Blaney, did not express her concern about the economic repercussions of this decision before the Minister made her announcement. In my opinion, it does seem likely that she put the interests of her family before those of her constituents.
This is yet further reason why it is right that the decision should be reviewed by the Federal Court before any farms are closed. In addition, it is the Fisheries Minister who should have a separate plan in place for when the wild salmon fail to return and after all the other economic activity has been removed from the region.