Frequently asked questions about seafood
Here are some frequently asked questions about seafood. Feel free to contact us if you have questions you want answers to.
What is seafood?
Seafood is defined in the Swedish dictionary as:
(for humans) edible animals and plants living underwater such as fish, shellfish and algae.
Which seafood can I eat and how much?
For most people, 'eat more' is good advice. But there are a few things to consider, especially for certain groups such as children, young people and women who want to become or are pregnant.
You can find advice on seafood on the website of the Swedish National Food Agency.
What is seaweed, algae and sea grass?
Seaweeds are perennial macroalgae, i.e. algae that we can see with the naked eye and that live longer than one season. Read more about seaweed on, for example, the Seaweed Blog.
Algae are not plants but a type of organism that lacks conduction tissue, the equivalent of our bloodstream. Algae are well described on Wikipedia
Seagrass is easily confused with 'seaweed', but while seaweed is another word for algae, seagrasses are flowering plants that are pollinated underwater. In Sweden, eelgrass in particular performs important ecosystem services, including binding bottom sediments and creating an important habitat for many marine species. But it's not something you want to eat.
Can it be grown?
Can you grow seaweed in lakes?
Seaweed needs salt water to survive. Even the waters of the Baltic Sea are too low in salinity for seaweed cultivation. In Sweden, however, it is possible to grow seaweed in the North Sea and in containers on land.
Can you grow mussels in the Baltic Sea?
It is certainly possible to grow mussels in the Baltic Sea. Although they do not grow as large as in the North Sea, they capture nutrients such as nitrogen and phosphorus, they improve visibility and, although their size makes them unsuitable as sea food, they can be used as animal feed. Research from SLU shows that new cultivation techniques and larger farms can make mussel farming an effective environmental measure for the Baltic Sea.
How much fish is caught in Sweden?
Fish volumes vary from year to year, partly due to quotas.
In 2024, Swedish fishermen caught just over 130 000 tons of wild fish and shellfish. Around 117 000 tons, about 90% of the total catch, consisted of small pelagic fish such as herring, sprat and sandeel. Just over 72 000 tons, around 68%, were used for feed. Around 68% of all fish caught by Swedish fishermen in 2024 was landed in other countries, mainly Denmark.
The commercial freshwater catch was just over 1,600 tons in 2024. The most economically significant species are zander and crayfish.
In addition, so-called reduction fishing is carried out to improve water quality.
What is reduction fishing?
Reduction fishing involves catching large quantities of cyprinid fish, such as bream and roach, in nutrient-rich lakes. This reduces the pressure on zooplankton, which after reduction fishing becomes more numerous and in turn limits the amount of phytoplankton. It reduces the nutrient content of the lakes and improves visibility. It also reduces the risk of algal blooms.
Reduction fishing has been shown to have positive effects on water quality, as measured by water clarity and chlorophyll, especially in small, shallow and heavily eutrophic lakes.
The catch from reduction fishing often goes into biogas production but there are initiatives to use this type of fish to make mince. Hopefully, more can be used as seafood in the future.
How much fish is farmed in Sweden?
In Sweden, around 10 000 tons of fish, crayfish and molluscs are farmed for human consumption annually. In 2024, 7 700 tons of rainbow trout, 830 tons of char and 850 tons of mussels were farmed. This is less than 1% of Norwegian salmon farming. So there is great potential to increase Swedish sustainable aquaculture.
Read 25 answers on fish farming and aquaculture on the website of the Swemarc research center.
The Swedish Board of Agriculture collects statistics for Swedish aquaculture, the latest compilation is from 2024.
What are extractive species?
Extractive species are animals and plants that obtain their food or nutrients from the surrounding water. Examples of extractive species include algae, mussels, oysters and seaweed. In addition to being self-sufficient in food and water, extractive species help to reduce the amount of nutrients in eutrophic waters.
What is the production of extractive species in Sweden?
In Sweden, 850 tons of mussels were farmed in 2024. Swedish seaweed farming is a growing industry but the total volumes are still limited. Swedish oyster farming and oyster fishing are also small-scale.
What are pelagic and demersal species?
Pelagic species are those that live in the open sea, such as herring, sprat and mackerel.
Demersal species live at the bottom of the sea and in lakes, such as cod, saithe and Norway lobster.
How much small pelagic fish is caught and how is it used?
In 2024, Swedish fishermen caught around 117 000 tons of small pelagic fish such as herring, sprat and sandeel.
How much of the fish is used?
During filleting of both wild and farmed fish, as well as processing of seafood, 50-70% of the weight of the fish is lost as residues. Often more than half of the residue consists of primary muscle that could be used as alternative cuts instead of being considered as scraps.
What is the difference between...
wild caught fish and farmed fish?
Wild-caught fish are those that live in seas and lakes and are caught with various gears, usually from boats. Farmed fish are raised in different types of farming systems in the sea, lakes or on land.
fed and unfed aquaculture?
Examples of fed aquaculture include the farming of fish and crustaceans. Unfed aquaculture involves so-called extractive species that take food or nutrients from the water, such as mussels, oysters and algae.
underutilized species, side streams and species underutilized for food production?
- Underexploited species are those that are fished far below the levels that stocks can sustain, such as bream and id in Sweden, which we do not eat to any great extent for historical reasons or because they have a lot of bone, for example.
- Side streams can be, for example, fish scraps such as backbones, fish heads and shellfish remains from fish that we eat other parts of.
- Species underutilized for food production include small pelagic fish such as herring, sprat and sandeel, which are thus exploited but not for human consumption. Most are exported and used to produce fishmeal and fish oil.
What is the carbon footprint of seafood?
Seafood is a broad concept and includes everything from algae to fish (see 'What is seafood'). Moreover, each species can be produced in different ways, resulting in completely different carbon footprints. However, it can be said that, on average, seafood has a lower carbon footprint than meat from land animals. But it is equally true to say that the carbon footprint spans the entire range of other foods, from the lowest to the highest emissions. Therefore, it is important that we develop the right species and production methods - and improve those that already exist.
Vegetables and algae usually have a lower carbon footprint than animals, and this also applies to seafood. However, they also have lower bioavailability of the nutrients they contain. For seafood from fisheries, it is the fuel consumption in the fishery that determines a large part of the carbon footprint and it depends both on the fishing method used and the health of the fish stock. For farmed seafood, it is the amount and type of feed used that dominates the carbon footprint. Therefore, species that do not need feed (see 'What are extractive species'), such as mussels, algae and scallops, have a major climate benefit.
The production chain on land generally has much less impact than fishing or farming, except when fresh seafood is flown to market. Fortunately, this is rare, and the vast majority of seafood, both fresh and frozen, is transported by truck or container ship, so the carbon footprint of transportation is very small compared to upstream. This means that just because it is produced nearby, it is not necessarily sustainable or climate-smart. The most important thing is always to ensure that the production itself is as sustainable as possible - and to avoid air freight.
Here you can read more about the climate impact of transport.
Photo from Vattudalen fish