1 in 4 salmon in sea cages are dying: What can we do to stop it? 

Myriam Hammadi

January 30th, 2023

"Salmon deaths on fish farms in Scotland nearly doubled last year, official figures show, owing to growing levels of disease, parasites and jellyfish blooms”. About one in four salmon in sea cages are dying in Scotland (the Scotsman, Jan. 2023).  

Salmon production has been on the rise in the past decade (see Figure 1) but the top 3 salmon producers – Norway, Chile and Scotland – are now seeing their industries at danger of collapse: the salmon population is dying at historical levels (see the Scotsman , Science Norway, National Geographic).   

Figure 1: Global production of Atlantic salmon in the last decade 

The main causes for salmon deaths are twofold: poor sanitary conditions and environmental problems. 

The sanitary causes include a series of illness, viruses and bacteria that cause death and they include the infectious salmon anemia (a virus that causes anemia), gill disease, pancreatic disease, and sea lice. Infectious salmon anemia has been one of the main concerns in Chile, since a brutal outbreak in 2007, and is still monitored very closely to prevent a new outbreak (Shamba Centre). Gill disease is largely a concern in Scotland, as over 70% of the declarations concerning salmon deaths in Scotland between 2019 and 2022 cited gill disease as the cause. In Norway, one of the main sanitary causes for salmon death was pancreatic disease (cf. NORCE report), caused by a virus which infects the pancreas of the fish, leading to malnutrition and starvation. 

The environmental causes include toxic algal blooms, eutrophication, low levels of oxygen and jellyfish.  In the past two years, over 12 percent of the declarations made to the Scottish fishing authorities identified the “environment” as the cause for salmon deaths. Low levels of oxygen and toxic algal blooms are a growing concern in Chile, as they represented a quarter of the deaths in 2021,  doubling from the previous year, and rising to the number one cause of death in the Chilean salmon population (cf. Boletín ambiental, Sernapesca 2020). Toxic algal blooms have also been a concern in Norway (see New York Times article). Finally, jellyfish blooms have been affecting fish stocks, causing historic levels of gill disease in Scotland. Jellyfish contain a toxin that damages the gills of the salmon, making it difficult for the fish to breathe. This can lead to infections and ultimately, death. 

Why have these causes of death increased so significantly in the past few years?

The answer to the massive rise in deaths is linked to the methods of production. Cage-based production has globally increased in the past few years, mainly in seawater farming. One of the reasons is that cage-based farming requires lower capital investment per unit of production and, at adequate scale, has lower operating costs than other methods of intensive aquaculture (source).This is true in Norway, Chile and Scotland.  

But cage-based farming can have negative environmental consequences. Cages sit in the ocean, so the fish stock in the cages are affected by the natural environment, and the methods of production inside the cages (e.g. from chemical inputs, antibiotics use, and organic matter resulting from production) can affect the natural environment.  

The excess of feed and antibiotics released in the ocean can only be absorbed up to a certain point. Beyond that, they alter the ecosystem surrounding the cages, causing eutrophication (too much concentration of nutrients) and antibiotics that are released threaten wildlife and the surrounding biodiversity. Furthermore, if the cages have high density of salmon, which is the case in intensive salmon farming, it creates stress and increases the susceptibility of the fish to infectious diseases.  

Why are these practices continuing if they cause so many negative consequences that could make the industry collapse?   

Alongside the growth of the salmon industry has come an increasing concentration of market power by fewer and fewer companies. A series of mergers and acquisition has increasingly allowed big and historical companies to dominate. This is evident in all three major producing and exporting countries: from 30 operators to 10 operators in Chile, from 70 to 23 operators in Norway and from 10 to 4 players in Scotland (see Figure 2).  

Market concentration in the salmon industry has allowed large companies to expand their market share by acquiring smaller firms. Bigger cages are preferred by large players in the salmon industry due to their higher production yields and better stability. Nevertheless, bigger cages are worse for the environment because they contain more biomass and therefore release more nutrients into the surrounding water, which amplifies the extent of the abovementioned damage on the ecosystem.

Figure 2: Number of players in producing countries (source: Mowi handbook, 2022)

What has been done?  

The governments in these three countries have responded. In some cases, for the better, in others for the worse. Moratoriums have been put in place that are doing more harm than good, but 5 other ideas are worth exploring.  

1. Moratoriums: a cure worse than the disease  

Chile and Norway have put in place moratoriums for new market entrants. Chile did it to address the sanitary issues. Norway did it to reform the regulatory landscape in the salmon industry. But in both cases, the cure is worse than the disease. A moratorium on new entrants strengthens the market power of the big and historical companies, stifling competition, innovation, and undermining efforts to change production methods.  

2. Promoting more competition through the aquaculture tax: results to be observed in the near future 

Three weeks ago, Norway, introduced a new 40% aquaculture tax for companies producing over 4,000 or 5,000 metric tons of salmon, trout, and rainbow trout. It is designed as a ground rent tax and is considered a rental fee for the use of natural resources. The minister promoting the tax, Trygve Slagsvold Vedum, said the goal is to affect large companies and shield small ones. It is way too early to know the effects, but there are two things to look out for. First, a tax of this size is going to create a shake-up for the companies that will be subject to it, with associated job losses, bankruptcies, and potentially accelerate mergers and acquisitions. Another scenario is that the tax will make it easier for smaller players – who will not be subject to the tax – to enter the market and acquire licenses.  

A nuance is needed, regardless of the scenario. The fact that this tax is introduced on existing licenses and not only on new ones, is disrupting stability and predictability, notably from a cost perspective. In this frame, mass redundancies to be expected, as it is already the case at SalMar. 

3. The green licenses 

In 2013, Norway opened up 45 new salmon farming licenses subject to strict environmental criteria on sea lice, escape risk and other environmental factors dubbed “Green Licenses.” 

In this frame, farmers were given the opportunity to expand production if they developed new production methods that could reduce the problems of sea lice and salmon escapes. Farmers would also report on their experiences with the solution the adopted and tried out. 

The main drawback is that these licenses are quite expensive – between 1 and 4 million USD (10 to 40 million NOK), which is a limit to entry for smaller and new players.  

Other drawbacks include the fact that the scientific basis for the assessment of the green licenses is questioned, as well as the fact that the government counting is flawed, since some salmon farmers might be underreporting cases of lice, and salmon escapes. (source) 

What more can be done?  

4. Reforming the competition law and policy to encourage innovation  

Encouraging competition can lead to advancements in addressing sanitary and environmental issues. Competition benefits consumers by providing lower prices, higher quality products, and innovation. It is through innovation that we can find ways to improve products and develop methods that are less harmful to the environment and that promote better sanitary conditions. Additionally, competition in the marketplace can also improve job opportunities and provide workers with more options for higher wages and better working conditions. (Shamba Centre) 

5. Encouraging the adoption of natural processes and resources to help with the industries challenges: the nature-based solutions 

Reforming the policy landscape, so that it promotes and encourages the adoption of nature-based solutions and polyculture. Nature-based solutions are ways to use natural processes and resources, to protect, manage and restore ecosystems in a sustainable way to address societal challenges such as climate change, disaster risk, food and water security, biodiversity loss, and human health.  

This can be done through a method called integrated multitrophic aquaculture (IMTA) which can, for example, combine sea cage salmon farming with other biological cultures (e.g. mussels): other organisms can feed on the waste products from salmon farms for their own growth, resulting in an increase of total yield (see Figure 3).  

Figure 3: Integrated multi-trophic aquaculture (source: Susan Løvstad Holdt) 

6. Promoting good production methods from market incentives: having consumers on board.  

The producing States could put in place market incentives to improve production methods, notably through State labeling or certification. Producing states could collaborate or get inspiration from independent organizations such as the Aquaculture Stewardship Council which provides for a strict protocol to assess salmon farms – including their sanitary and environmental situation.  

Giving a clear visual identity to sustainably farmed salmon will help consumers identify it as a healthier, better quality and more sustainable and will therefore provide the product with an added value on the market.   

Ultimately, if producer countries do not put in place such certification standards, importing countries can then become the engine of change and encourage certain production method through a better valuation on their markets, or through the principle of equivalence. In this frame, the importing country imposes the same (strict) rules on both local and imported products to consider them both as “sustainably produced”. This principle was used in the European Union, and since 2022, for an imported product to be sold as an organic product, it must meet standards equivalent to those of European products.  

Preserving natural capital is essential for this industry to maintain its growth levels. There are solutions, in which Norway, Chile and Scotland can invest, whether they are tax measures, competition law reform, new labeling rules, or promoting solutions based on nature. Regardless of which solution is adopted, it will be necessary to be careful about its design and to limit eventual collateral damage (redundancies, market power strengthening, etc.)

Sources:  

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