Salmon disease control plan published

The Fish Site
by The Fish Site
7 December 2006, at 12:00am

SCOTLAND - A contingency plan to tackle a disease which could wipe out 2000 jobs if it contaminated Scottish salmon stocks was published today.

Gyrodactylus salaris (Gs), a deadly parasite of Atlantic salmon, is not present in Scotland but is found in Scandinavia. The Contingency Plan sets out steps that would be taken if an outbreak were to occur in Scotland.

Launching the action plan, Deputy Environment and Rural Development Minister Rhona Brankin said:

"Gs presents a significant risk to our salmon fisheries and freshwater aquaculture and I am grateful to all those who have contributed to this important piece of work.

"We now have a Contingency Plan but under existing legislation we could not attempt eradication of the parasite should it arrive.

"We are seeking these powers through the Aquaculture and Fisheries (Scotland) Bill and I very much hope that the Scottish Parliament will give us the tools we need."

An exercise to test the robustness of the Contingency Plan will be held with major stakeholders early in 2007.


Gyrodactylosis is a notifiable disease of salmon, caused by the parasite Gyrodactylus salaris, which if introduced into Scottish salmon rivers has the potential to cause widespread losses in the valuable stocks of wild Atlantic salmon.

Gs is a freshwater monogenean helminth parasite (skin and gill fluke) which has caused the virtual elimination of Atlantic salmon stocks from a number of rivers in Scandinavia and Northern Russia. Gs poses no risk for human health.

Gs causes disease in Atlantic salmon, uses rainbow trout and Arctic charr as carrier hosts on which it can reproduce and uses brown trout as a transport host. Gs may reproduce on brown trout but not at a rate sufficient to maintain a viable population in the absence of Atlantic salmon.

The parasite is exotic to Scotland and it is highly improbable that the infection could enter the country by natural means because of the inability of the parasite to survive in full strength seawater.

The importation of live salmonids and of non-disinfected ova from areas of lower health status, with respect to Gs, is prohibited into the United Kingdom and the risk of introducing Gs from infected areas via leisure equipment (fishing tackle, canoes etc.) has been assessed as extremely low.

SEERAD hosted a workshop on Gs, in February 2005, which recommended that a Task Force be set up to look at the risk of the parasite entering Scottish waters and develop a Contingency Plan for dealing with the parasite. Arthur Griffiths MRCVS, who was formerly a Divisional Veterinary Manager in the State Veterinary Service, was appointed to chair the Task Force. Mr Griffiths has wide experience of dealing with notifiable diseases in farm animals and creating contingency plans to deal with them.

The contingency plan was produced by the Scottish Executive Environment and Rural Affairs Department (SEERAD), Fisheries Research Services (FRS) which includes the Fish Health Inspectorate (FHI), Scottish Environment Protection Agency (SEPA), State Veterinary Service (SVS), District Salmon Fishery Boards (DSFBs), Scottish Natural Heritage (SNH), Scottish Water and Local Government Authorities in affected areas. Equivalent bodies in England (Environmental Agency and English Nature) will be involved where catchments cross the Scotland/England border. Successful control action will rely on assistance from all riparian owners, occupiers, angling organisations, fish farmers and all those commercial and leisure activities that rely on water resources for all or part of their activities. The Contingency Plan defines the roles of the organisations and agencies that would be involved in responding to an outbreak of Gs. It details the range of issues to be taken into account in deciding whether to prevent the spread of the parasite or attempt eradication.

Several of the actions needed to eradicate an outbreak of Gs require additional powers that are included in the Aquaculture and Fisheries (Scotland) Bill currently before the Scottish Parliament.

An Economic Evaluation, carried out by Stirling Aquaculture, shows that the cost of eradicating the parasite in small catchments would be economically justified. Further evaluation is needed for larger, more complex catchments that include industrial users of water. In all cases Scottish Ministers would be obliged under the Habitats and Water Framework Directives to take into account the environmental, social and economic consequences of any proposed action. If it were found that the remedy was worse than the disease, then Ministers would not pursue eradication, but would work to contain the disease.

The Contingency Plan and Economic Impact Assessment can be viewed at: Also to be found through this link is the Report of the Chairman of the Task Force, including the recommendations of the Task Force Sub-groups. These are being evaluated by SEERAD and account will be taken of any views of the Scottish Parliament on the Gs provisions of the Bill.

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