Atlantic Salmon

Salmo salar

Sources, Quantities and Cultivation Methods

Sources and Quantities

Atlantic salmon (often known simply as ‘salmon’)1 is native to the North Atlantic and its islands (e.g. UK, Iceland, Greenland, etc.). Wild Atlantic salmon are anadromous; spending their adult life in the sea but swimming upriver to freshwater spawning grounds. After hatching, young salmon stay in rivers as parr for 1-5 years before undergoing physiological changes (smoltification) that enables them to migrate out to the open ocean. They head for deep water feeding grounds, and after 1-4 years the mature fish return to their home rivers to spawn2.

Wild populations of Atlantic salmon are generally at low levels and capture fisheries have seen significant decline2. Commercial fishing is now limited. Almost all commercially available Atlantic salmon is farmed and from locations with the necessary environmental and geographical characteristics (i.e. water temperature and indented coastlines).

Apart from being farmed across its native range Atlantic salmon are also cultured as a non-native species along the coast of North America’s Pacific Northwest (i.e. British Columbia) and in countries such as Chile and Tasmania.

Atlantic salmon is one of the most important farmed finfish species in the world and its production is highly efficient. Global production has increased markedly since the early 1990's from around 30,510 tonnes in 1993 to over 2.43 million tonnes in 2018, valued at just over US$17 billion3.

Global Atlantic Salmon Production: Key Locations and Volumes 2018 (2, 3)

As the map shows, Norwegian production is dominant and is over double that of its closest competitor, namely Chile. The UK (Scotland) and Canada are the other two major producers. These four countries represented some 91% of world Atlantic salmon production in 20183. During the last decade the salmon farming industry has seen a period of consolidation and production in each of the ‘big four’ is undertaken by five to ten companies4. Many of these companies are global enterprises with facilities in multiple countries.

Europe (including Russia) and North America are by far the largest markets for Atlantic salmon. However, emerging markets (such as Brazil and Asia) are growing at significantly higher rates than these traditional markets4. Farmed salmon is now Scotland’s largest food export by value and over 50 countries imported Scottish salmon in 2016, with the US and France being the largest markets5. Scottish salmon was the first fish and first non-French product to be awarded the Label Rouge quality mark6.

Domestic Market Information7, 8

‘Salmon’ has grown to dominate the seafood market in Great Britain (i.e. England, Scotland and Wales) in terms of both value and volume, the majority of which is farmed Atlantic salmon. From 2008 to 2017 salmon was the only one of the top five seafood species to show market growth despite having a relatively high average price. In 2018 the long-term run of volume growth ended; as value grew by 51.2% and volume declined by -4.8% from a base of £611m and 54,361 tonnes in 2008, and the significant inflation impacted on shoppers value for money perception. Salmon has the highest average price of any of the top ten seafood species; over double that of cod and haddock.

In June 2018 UK salmon retail sales were worth £1,056 million (+3.6% compared to June 2017) with a volume of 62,190 tonnes (-8.5%), average price £16.98 per kg; still ranking as the most popular UK seafood by value and volume (in the 52 weeks up to 16/06/2018 (including discounters)).

In 2018, the UK imported a total of 84,190 tonnes of salmon, including 58,028 tonnes of chilled Atlantic salmon.

Note: the difference between the volume of salmon sold in UK retail and that which is imported is due to its use in the foodservice industry (e.g. restaurants) (no data available) and that which is re-exported.

Production Method

Atlantic salmon farming replicates the species natural cycle. It is divided in to two phases; freshwater - hatchery and smolt production, and seawater – growing the fish through until harvest4, 9, as shown in the production schematic below.

Atlantic Salmon Production Schematic (adapted from 2)

Selected adult broodstock are stripped of eggs and milt (sperm), and the eggs are fertilised.  The first life stage or alevin have a yolk-sac and once absorbed they become free swimming fry and then develop further in to parr.  These initial stages take place in freshwater tanks and the fry and parr are fed commercially available pelleted feeds tailored to their specific requirements. Parr develop further into smolts and at this stage they are ready to go to sea.

Traditionally in Scotland, parr are transferred to net-pens in freshwater lochs for further on-growing into smolts. Whilst this method is still important, industry is increasingly using sophisticated onshore recirculation systems which provide producers with greater control and faster growth rates;  producing larger smolts and shortening the seawater grow-out phase10, 11.

Smolts can be transferred to the sea net-pens by several methods, including road, helicopter and well-boat. Once in the sea pens, the fish are fed a pelleted diet that is, again, tailored to their needs. The majority of Atlantic salmon are harvested after 14-20 months at sea, depending on the location12.

Fish are harvested at a size depending on the requirements of their destination market. Increasingly, the fish are transferred from the net-pens to a well-boat (a vessel with wells or tanks for the storage or transport of live fish) and transported to a shore-based harvest facility, where they are humanely stunned, bled and prepared for market. In Scotland a significant proportion of fish are now harvested directly into well-boats and 'dead hauled' to processing plants12.

References

  1. Defra
  2. FAO
  3. FAO FishstatJ
  4. MOWI
  5. SSPO
  6. SSPO
  7. AC Nielson
  8. HMRC
  9. FAO
  10. HIE
  11. Ellis, T., et al, 2016. Trends during development of Scottish salmon farming: An example of sustainable intensification? Aquaculture 458, 2016 p82-99
  12. SSPO, pers. comm., 2018