Preventing Gyrodactylus salaris

Prevent parasites: follow this advice from the Scottish Executive on how to avoid bringing the Gs bug to Scotland.

  • Dry equipment at a minimum of 20°C for at least 2 days
  • Heat for at least 1 hour at temperatures of above 60°C
  • Deep freeze for at least 1 day
  • Immerse in a solution* suitable for killing Gs for a minimum of 10 minutes

Gyrodactylus salaris is a parasite that can attack salmon. (Sea trout are not affected.) Salmon of the Baltic rivers of Sweden, Finland and Russia seem to be immune; however, infected farmed fish in Sweden took the bug to Norway, where it spread to vulnerable native salmon stocks and decimated them. ‘In Norway, for example, salmon stocks in 20 rivers have been virtually wiped out,’ according to the Scottish Executive. To date, the UK and Ireland are the only known Gs-free areas in Europe. Major efforts are underway to prevent it ever entering, as Norway’s recovery from the parasite has involved poisoning whole rivers, killing all organisms, before allowing nature to restore the ecosystem and before re-stocking. If it does enter the UK, it can reproduce very quickly indeed, which would have unfortunate effects on the £60m freshwater salmon industry in Scotland.

The parasite travels on damp and wet equipment such as waders, fishing equipment , bags, canoes, and windsurfing gear. The danger occurs when anglers, water sports enthusiasts or workers travel back to the UK from an infested area with wet equipment. The Gs bug can survive for several days in damp conditions. It can also arrive on other fish species such as eel.

* Chemical solutions which have been used include Virkon® Aquatic (1%), Wecodyne (1%), sodium chloride (3%) and sodium hydroxide (0.2%). Virkon Aquatic and Wescodyne are available from agricultural chemical suppliers. The use of trade names is for illustrative purposed only and does not signify endorsement of any particular product.

Information courtesy of SEERAD,

Anglers on the Findhorn please complete this Biosecurity Declaration and forward it to your proprietor at least two weeks prior to commencing fishing.  Biosecurity cover note.