Salmon & Trout Conservation Scotland makes formal complaint to European Commission on Scottish Government’s failure to address the impacts of sea lice parasites produced by Scottish salmon farms threatening west coast wild salmon and sea trout

Scottish Government called upon to improve dramatically the protection of wild salmon and sea trout from harm caused by poorly-managed marine salmon farms and remedy breach of European law

Salmon & Trout Conservation Scotland (S&TCS) has today submitted a formal complaint to the European Commission over the failure of the Scottish Government to do enough to control the sea lice parasite issue on Scottish salmon farms, which threatens the survival of key wild salmon and sea trout populations.

Wild fish conservation bodies in Scotland have very long standing and widespread concerns about lack of appropriate measures being put in place by the Scottish Government to control the impact on wild salmon and sea trout through the production and release by salmon farms of billions of juvenile sea lice on the west coast and off the islands of Scotland.

Fisheries scientists are firm in their conclusions that sea lice produced on fish-farms harm wild salmonids, both at an individual and at a population level. However, these threats are not being addressed by effective regulation and control of sea lice numbers on Scottish fish-farms.  Statutory regulation is essential to protect wild fish populations that are already significantly reduced (Notes 1 to 5).

Andrew Graham-Stewart, Director of S&TCS, said:

“The threat to wild salmonids – both Atlantic salmon and sea trout – from sea lice from fish farms on the west coast and in the islands of Scotland is well recognised, but the response of the Scottish Government to these threats has been and remains inadequate. Despite our best efforts over many years, the Scottish Government has not been persuaded of the need to act robustly to deal with the sea lice issue.

S&TCS has been left with no choice but to ask the European Commission to intervene.”

As the graph below – drawn up using data published by the Scottish Salmon Producers Organisation – shows, the problem with sea lice on salmon farms is deteriorating, with a growing proportion of the salmon farming industry failing to keep lice levels down.

Thankfully, European law, in the form of the Marine Strategy Framework Directive (MSFD), required the Government to publish, before the end of 2015, a programme of measures necessary to achieve or maintain good environmental status in marine and coastal waters by 2020, and to put those measures into effect by the end of this year (2016).

Importantly the MSFD requires the Scottish Government to put measures in place to protect wild salmonid fish from the threat of sea lice from the fish farms.

However, the published programme of measures is inadequate to address the sea-lice issue and hence achieve the objectives of the Directive.

Mr Graham-Stewart continued:

We believe that when the Commission cuts through all the ‘warm words’ and examines the detail of what the Scottish Government claims to have done, it will conclude, as S&TCS has, that the Scottish Government’s actions to date and ‘business as usual’ measures proposed are insufficient and inadequate to comply with European law designed to protect the marine environment.”

North Atlantic Salmon Conservation Organisation (NASCO) meeting in June

The complaint is being submitted in the run up to an important international meeting in salmon conservation. The Scottish Government is a party to NASCO, an inter-governmental organization established in 1984 under the Convention for the Conservation of Salmon in the North Atlantic Ocean to conserve, restore, enhance and rationally manage salmon stocks through international cooperation, taking into account the best available scientific information. 

The next meeting of the parties is in Bad Neuenahr-Ahrweiler in Germany from 7 to 10 June 2016. The meeting includes a full day Special Session on “Addressing impacts of salmon farming on wild Atlantic salmon”.

Paul Knight, CEO of S&TC UK and Co-Chair of the NASCO NGOs, explained:

“All nations that host wild populations of Atlantic salmon have agreed to work to conserve those populations, but we believe the Scottish Government is failing to protect these iconic fish from the effects of marine salmon farming, particularly the sea lice produced in their billions on those farms.

In the run-up to the NASCO meeting in Germany in June, with its spotlight on salmon farming’s impacts, we call on the Scottish Government to act to protect wild salmonids. Indeed, we can think of no better place or platform for the Scottish Government to announce its intention to remedy the woeful lack of effective legal protection given to wild fish from the harmful effects of poorly run fish farms in Scotland.”

S&TCS aquaculture campaign

The submission of the formal complaint to Europe is just the next stage in S&TCS’s on-going campaign to secure better protection for wild salmonids from harm caused by the salmon farming industry.

In late 2015, S&TCS published a detailed report into the control of sea lice achieved on fish farms in Scotland over the years 2013-2015, demonstrating the failure to control sea lice on Scottish salmon farms and the need for urgent action from the Scottish Government to protect wild salmon and sea trout populations (Note 6).

This year, S&TCS has also petitioned formally the Scottish Parliament to seek to persuade Scottish Ministers to increase legal protection for wild salmonids from the impact of fish farms (Note 7).

Mr Graham-Stewart added:

The Scottish Government consistently denies that wild fish are not sufficiently protected from fish farming activities, particularly from the huge production of sea lice on fish farms, but the facts speak for themselves.

We call upon the Scottish Government to stop relying on endless industry promises of improvement in the future – we have heard the same empty promises now for far too many years. The Government must take the bull by the horns and , as soon as possible, amend Scottish law to give marine inspectors a clear and unambiguous duty to protect wild fish from fish farm diseases and parasites”.



1) Just what is the problem with sea lice?

Adult wild salmon are perfectly adapted to coping with a few sea lice. Background levels of these parasites occur naturally in the sea. However the advent of salmon farming, particularly in fjordic sea lochs, has led to a fundamental change in the density and occurrence of sea lice in parts of the coastal waters of the west Highlands and Islands. Even one or two mature female sea lice per fish within a set of cages housing hundreds of thousands of farmed salmon amounts to a rampant breeding reservoir pumping huge numbers of mobile juvenile sea lice out into the local marine environment. The consequences when wild salmon and sea trout smolts, the metamorphosing fragile skin of which is not adapted to cope with more than the odd louse, migrate from local rivers into this “sea lice soup” can be devastating.

Carrying an unnaturally high burden of sea lice is known to compromise severely the survival of juvenile migratory salmonids. Lice feed by grazing on the surface of the fish and eating the mucous and skin. Large numbers of lice soon cause the loss of fins, severe scarring, secondary infections and, in time, death. Quite literally, the fish are eaten alive. Badly infested salmon smolts disappear out to sea, never to be seen again. In contrast afflicted sea trout smolts remain within the locality and they, together with the impact of the deadly burdens they carry, are more easily monitored through sweep net operations.

2) In 2015, the Scottish Government published its classification of the country’s rivers’ salmon populations. This places all the rivers in the west Highlands and inner Hebrides in the worst-performing category, with wild salmon stocks not reaching their conservation limits, which are a measure of the overall health of the population. No river within salmon farming’s heartland of the west Highlands and inner Hebrides has, according to the Scottish Government’s own scientists, a sufficient stock of wild salmon.

Sea trout populations too are under considerable threat with the number of sea trout returning to Scottish rivers in decline, with the 2013 rod catch being the lowest on record according to Marine Scotland Science. The west Highlands has in recent decades lost all of its formerly prolific loch fisheries for sea trout.

The negative impact of sea lice, produced in huge numbers by fish farms, on wild salmonids (salmon and sea trout) is widely accepted by fisheries scientists including the Scottish Government's own Marine Scotland Science. See Marine Scotland Science (2013) Summary of information relating to impacts of sea lice from fish farms on Scottish sea trout and salmon – 4th April 2013 – see Annex 1 of the Complaint.

3) A paper published in 2013 by a group of fisheries experts from Norway, Canada and Scotland re-analyses data from various Irish studies and shows that the impact of sea lice on wild salmon causes a very high loss (34%) of those returning to Irish rivers – see M Krkosek, C W Revie, B Finstad and C D Todd (2013) Comment on Jackson et al. Impact of Lepeophtheirus salmonis infestations on migrating Atlantic salmon, Salmo salar L., smolts at eight locations in Ireland with an analysis of lice-induced marine mortality – Journal of Fish Diseases.

4) Most importantly, there is clear evidence that both wild salmon and sea trout are in decline in Scotland's 'aquaculture zone', whereas, generally, populations have stabilized on the east and north coasts where there is no fish-farming see

5) In 2015, fisheries scientists from Norway, Scotland and Ireland reviewed over 300 scientific publications on the damaging effects of sea lice on sea trout stocks in salmon farming areas, and examined the effect of sea lice on salmon, concluding that sea lice have a potential significant and detrimental effect on marine survival of Atlantic salmon with potentially 12-29% fewer salmon spawning in salmon farming areas. The researchers concluded that: “Salmon lice in intensively farmed areas have negatively impacted wild sea trout populations by reducing growth and increasing marine mortality. Quantification of these impacts remains a challenge, although population-level effects have been quantified in Atlantic salmon by comparing the survival of chemically protected fish with control groups, which are relevant also for sea trout. Mortality attributable to salmon lice can lead to an average of 12−29% fewer salmon spawners. Reduced growth and increased mortality will reduce the benefits of marine migration for sea trout, and may also result in selection against anadromy in areas with high lice levels. Salmon lice-induced effects on sea trout populations may also extend to altered genetic composition and reduced diversity, and possibly to the local loss of sea trout, and establishment of exclusively freshwater resident populations.” See Thorstad , E , Todd , C D , Uglem , I , Bjorn , P A , Gargan , P , Vollset , K , Halttunen , E , Kalas , S , Berg , M & Finstad , B 2015 , ' Effects of salmon lice Lepeophtheirus salmonis on wild sea trout Salmo trutta – a literature review ' Aquaculture Environment Interactions , vol 7 , no. 2 , pp. 91-113 . (at

6) In December 2015, Salmon & Trout Conservation Scotland (S&TCS) published a detailed report (see into the control of sea lice on fish farms in Scotland over the last two years, brought into sharp focus the seriousness of the problem with sea lice and the need for urgent action from the Scottish Government to protect wild salmon and sea-trout populations that are already in trouble. The Report highlighted many regions of the Scottish Highlands and Islands  where fish farms were collectively above, often very significantly above, the industry’s own ‘good practice’ threshold (based on the number of adult female lice per farmed fish). At many of the fish-farms, despite repeated chemical treatments against sea lice, including using synthetic pyrethroid and organophosphate chemicals, the regional on-farm sea-lice levels remained stubbornly high. The Report made a number of recommendations for action from the Scottish Government, which the supermarkets are encouraged to support, including

– requiring the immediate publication of farm-specific sea lice data

– tougher regulation and inspection of fish farms;

– a Government-led review of the current voluntary code of practice, replacing it with a statutory code, as provided for in the Aquaculture Act 2007;

– introducing an ‘upper-tier’ sea lice threshold above which an immediate cull or harvest of farmed fish is required by law;

– amending Scottish legislation to protect wild fish from potential damage caused by fish-farms, with inspectors given a legal duty to control sea lice on fish-farms in order to protect wild fish populations;

– ordering the closure and / or relocation or persistently poorly-performing fish farms;

– signalling that the fish farming industry will be required eventually to move to full closed containment, to ensure a complete ‘biological separation’ of wild and farmed fish.

7) See