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Aquaculture, Introductions, Transfers & Transgenics

Salmon Farm Spacer Salmon Farm Spacer Farm Cages
Courtesy of SSPO

Salmon aquaculture includes farming, ranching and stocking activities. Salmon farming is a dynamic industry that has increased dramatically since NASCO's establishment. Salmon ranching is currently only conducted at an experimental scale in the North Atlantic. Stocking of salmon is conducted for a variety of reasons including restoration, rehabilitation, mitigation and enhancement. The rearing of transgenic salmon (i.e. salmon that have been modified by genetic engineering to contain DNA from an external source) is currently on an experimental scale in secure land-based facilities. There are concerns about the impacts of salmon faming, poorly planned introductions and transfers, and stocking practices on the wild stocks. Read more...

NASCO's goal is to minimise the possible adverse impacts of aquaculture, introductions and transfers and transgenics on the wild stocks of Atlantic salmon, working with industry stakeholders where appropriate. The key issues include:

  • minimising the escape of farmed salmon to a level that is as close as practicable to zero;
  • minimising any negative impacts of ranched salmon by utilising, as far as possible, local stocks and developing and applying appropriate release and harvest strategies;
  • minimising the adverse genetic and other biological interactions from salmon enhancement activities including introductions and transfers;
  • minimising the risk of transmission to wild salmon stocks of diseases and parasites from all aquaculture activities and from introductions and transfers.

NASCO's ‘Williamsburg Resolution’ is designed to minimise impacts of aquaculture, introductions and transfers and transgenics on the wild stocks. Read more...

Salmon farming

Production of farmed salmon in the North Atlantic in 2010 was approximately 600 times the harvest of wild fish. An International Salmon Farmers' Association (ISFA)/NASCO Liaison Group was established to consider issues of mutual concern. Read more...

In 2013, the Council decided that the regular meetings of the Liaison Group would not be continued, but, if a specific need arose, consideration could be given to convening a joint ad hoc group. It agreed to retain an agenda item s entitled ‘Liaison with the Salmon Farming Industry’, during which the International Salmon Farmers’ Association (ISFA) could be invited to participate in an exchange of information on issues concerning impacts of aquaculture on wild salmon.

Farmed Salmon Production
Production of farmed Atlantic salmon (tonnes) in the North Atlantic (Source: ICES)

In 2009, the Liason Group had developed 'Guidance on Best Management Practices to Address Impacts of Sea Lice and Escaped Farmed Salmon on Wild Salmon Stocks'. Read more...

The international goals of this BMP Guidance are:

  • 100% of farms to have effective sea lice management such that there is no increase in sea lice loads or lice-induced mortality of wild salmonids attributable to the farms.
  • 100% farmed fish to be retained in all production facilities.

The Liason Group had developed an explanation of the terms used in this BMP Guidance. Read more...

Introductions and transfers

There are risks associated with movements of salmonids. These risks have been highlighted by the spread of the parasite Gyrodactylus salaris which has caused very serious problems in some parts of the North-East Atlantic Commission area following its inadvertent introduction from the Baltic Sea. Read more...

Progress in implementing NASCO's Agreements and Guidelines relating to the aquaculture, introductions and transfers, and transgenics is assessed through review of Implementation Plans, focus Area Reports and Annual Progress Reports. Read more...