Scope#39 | Danish Salmon A/S

Swimming Upstream
Against All Odds, Danish Salmon is Leading Land-Based Salmon Farming.

Atlantic salmon, aka the “King of Fish,” is a versatile seafood. Cooked, smoked, or raw, it is tasty. It is also highly nutritious yet lower in fat than meat—another reason for the ever-growing appetite for Atlantic salmon around the globe.

Atlantic salmon are migratory fish. They leave rivers to spend a few years at sea before they return to spawn. As populations of wild species have severely declined, virtually all Atlantic salmon in stores today are farmed. The two largest producers are Norway and Chile; combined, they produce 80 percent of the world’s supply. Sea-based farming, through which fish are cultured in open-net pens, requires cold waters and sheltered fjords. Such locations, however, are limited to high latitude regions.

“About 90 percent of the world’s surface is not suitable for farming Atlantic salmon, so we thought, ‘What if we recreate optimal conditions on land?’” says Kim Lyhne, CEO of Danish Salmon, explaining the inception of the company in 2009, when it started to grow Atlantic salmon entirely in indoor fish tanks at its facility in Hirtshals, Denmark, using a Recirculating Aquaculture System (RAS). At a RAS facility, the same water keeps recirculating for a few weeks with a very small, gradual intake of new water, during which it is filtered both biologically (to remove ammonia with bacteria) and mechanically (to remove solid waste), disinfected, and oxygenated.

At the time, land-based salmon aquaculture had been practiced for growing juvenile fish in fresh water, but using a combination of fresh water and seawater to grow full-size Atlantic salmon on land only was extremely challenging.

When Lyhne joined Danish Salmon in 2012 as a new university graduate with a business degree, the company was still struggling to make it work; both the volume of production and the size of the fish fell far short of what they had aimed to achieve with the amount of feed that they were using. It was not until 2018, when they had a successful proof of concept, that they finally produced a batch of fish, the average size of which was 4.5 kilograms, in a way that they had expected, within the timeframe that they had expected. “That was when we realized that the only thing that we needed to do now was to replicate these results and eliminate all the problems that could possibly hinder us from achieving our goals.”

Danish Salmon imports eggs, but it does everything else—from incubation to harvest, as well as processing, packing, and shipping. Harvest takes place every two weeks, throughout the year. Its annual production, which currently stands at 1,100 metric tons (about 800,000 fish swimming around), is expected to increase to 2,700 metric tons by 2023, when the increased capacity starts operating in earnest.

Land-based is the Future of Sustainable Salmon

In 2020, Marubeni ventured into land-based aquaculture by investing in Danish Salmon, a pioneer and one of the very few successful companies of this emerging business. While the future supply of Atlantic salmon by traditional sea-based farms will most likely be restricted, because of the limited availability of suitable coastlines as well as growing concerns for its impact on the ecosystem, land-based farming holds high growth potential. It can be practiced anywhere, in proximity to consumers, which can significantly minimize transport emissions.

“As is already happening here in Europe, global consumer demand for sustainable products is expected to grow,” says Kazuki Kaida, manager of Danish Salmon, who came from Marubeni. He adds that global demand for Atlantic salmon is also on the rise largely because it is suitable for being eaten raw in popular dishes such as sushi. Danish Salmon and Marubeni are currently focusing on the European market, but their long-term goal is to spread land-based salmon aquaculture using a RAS to many parts of the world that are currently importing Atlantic salmon all the way from Norway or Chile. “Our mission is to deliver sustainable salmon that are raised in a sustainable way, to consumers around the world,” Kaida says.

Experts say that land-based farming has many advantages over sea-based farming, both from an ecological and a production point of view.

“It gives you a chance to clean water before it is discharged,” says Dr. Per Bovbjerg Pedersen, head of the aquaculture section of the National Institute of Aquatic Resources at Technical University of Denmark. Nutrient pollution is a big challenge for open-net pen farms to tackle, because feces and uneaten feed are directly released from cages into the ocean. Such waste contains nitrogen and phosphorus, the culprits of algae blooms, which cause oxygen depletion in the waters. Such nutrients are removed from the effluent of land-based farms because it is properly treated.

“You have much more control over your production,” Dr. Pedersen says, adding that various parameters, which are important for the fish, such as salinity, temperature, and pH, can be strictly controlled at a land-based facility. “And you are not dependent on (or affected by) the conditions of nature, such as wind, rain or storm.”

Recreating Natural Conditions on Land

The production cycle of the 4.5-kilogram fish at Danish Salmon stretches to 22 to 24 months. When they become ready to “migrate” after living in fresh-water tanks for 9 to 11 months, the fish are transferred to seawater tanks. Deciding when to do this is the most critical part of the operation, because the fish cannot survive if they haven’t developed seawater tolerance.

“We try to mimic nature,” says Arndt von Danwitz, production manager at Danish Salmon. Controlling the seasons is difficult yet key to successful production because salmon growth hormone is mainly controlled by daylight. Over the course of many years, Danish Salmon has established effective artificial lighting programs, by which they simulate several summers and several winters every year, for different families of fish.

Keeping good and stable water quality is also critical yet quite challenging. Salmon are very sensitive fish; a miniscule change in the system can be a big stress for them. “We always have to be alert. Very often, something unexpected happens,” von Danwitz says. “We work with living animals—in our case, living fish and living bacteria, and both have different demands.”

Not Only More Sustainable, but Superior Quality

“I find the fillet to be very thick, the taste to be very clean,” says Jasper Hansen of Fiskerikajen, a seafood store in Copenhagen that sells Danish Salmon’s products.

Atlantic salmon that are raised at a land-based facility taste good not only because they are produced locally and delivered fresh. They are superior in quality than those raised in conventional sea-based farms because they are leaner, Lyhne says. “We are constantly exercising the muscle of the fish.” At Danish Salmon, the fish in seawater tanks are swimming against high-velocity currents to develop a better cardiovascular system, whereas the fish that are raised in cages at sea are more static, which often leads to the development of excessive body fat. Wild salmon live in a harsh environment and they burn a lot of energy especially when they are swimming upstream. “That is why we always compare our fish to wild salmon,” Lyhne says.

When the company was still in the experimental phase, trying to identify problems and figure out solutions, “there was too much faith in technology, doing things automatically,” Lyhne says. What was needed most was to understand better and deeper about the biology and the well-being of the fish growing in a RAS by frequently checking on them; how much they weigh, how much they eat, how mature they are.

“We have a lot of technologies that can help us ensure the stable environment for the fish to thrive in, but this technology has to be run by people,” Lyhne says. He adds that the most important thing for the successful operation of the land-based aquaculture business is to have the key staff that understand their responsibilities and also have the mindset that this is a 24-hour job. “If you get an alarm, you have to react to it. This is simply the most important thing that we do here every single day.”

All information contained in this article is based on interviews conducted in November 2021.