CONSERVATIONISTS have launched the largest every study into the migrating habits of wild salmon to try to discover why numbers in Scotland have declined so dramatically.

Figures show the numbers of wild salmon and sea trout found in Scotland’s rivers have declined by 70% over the past two decades, raising fears for the future survival of the species.

One reason being blamed is the number of fish farms situated in migrating areas which are said to be damaging the stocks as many are sited in migration grounds as wild salmon head upstream.

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There are now 250 salmon farms on the west coast of Scotland and campaigners say the surge has coincided with a collapse in the number of wild salmon in the area.

Now a large-scale project which aims to track wild Atlantic salmon over the next two years will be launched in the Highlands today as part of the largest effort in Europe to halt the decline of the species.

The Missing Salmon Project hopes to discover why the fish is in such sharp decline which they say is essential if effective measures are to be found to reverse their fortunes.

Executive director of the Atlantic Salmon Trust, Sarah Bayley Slater, said: “Salmon have been around for more than 60 million years, but their future looks very bleak indeed.

“If the decline we’ve seen across the Atlantic and in Scotland continues, the wild Atlantic salmon could be an endangered species in our lifetime.

“In launching the Missing Salmon Project, we are making our stand now and giving our generation a chance to save the species before it’s too late.”

The project will tag juvenile fish, known as smolts, as they begin their journey from their home river towards the sea.

Fish will be recorded as they pass through strategic points, which will help determine how many fish make actually it to the ocean and where mortality occurs.

The tracking project will start in the Moray Firth where 20% of all salmon that leave the UK originate and the lessons learned will be transferable to other populations of salmon around the UK.

Dr Matthew Newton is the tracking co-ordinator for the AST, said: “If we’re going to have a meaningful impact on reversing the Atlantic salmon’s decline, we need to tag and track fish on a scale never seen before in Europe”.

“By tagging the fish and tracking their progress from their spawning ground and back again, we’ll be able to pinpoint where fish are being lost – and help identify the causes for their increasingly worrying mortality rates.”

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Global populations of wild Atlantic salmon are estimated to have declined from 8-10million in the 1970s to just 3 million fish today so the project organisers believe the project will have an international impact.

It also comes amid growing concern about the siting of fish farms, which produce around 180,000 tonnes annually, amid plans to double production by 2030.

Salmon & Trout Conservation UK (S&TC UK) has claimed the upsurge has come at ‘considerable environmental cost,’ by triggering a huge surge in sea lice which are threatening trout as well as salmon.

The numbers of the parasites are frequently over the industry’s recommended Code of Good Practice threshold for treatment.

Lice feed by grazing on the surface of the fish, eating the mucous and skin. Large numbers of lice soon cause the loss of fins, severe scarring, secondary infections and, in time, death.

The sea louse problem has led most fisheries needing to add chemicals to cages, which are harmful to the environment, conservationists have warned.

Last year’s run of salmon in the most closely monitored river in Argyll is on course to be the lowest on record. The salmon count on the River Awe hit an all-time low after 30 weeks of the season.

Last year’s total of 807 fish was only slightly above the all-time lowest count. This year it is running at only one third of the 2016 count.

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Now the Atlantic Salmon Trust, plans to raise £1million via crowdfunding to support the tracking project in a bid to find a solution to the declining numbers.

The £1m will pay for the tags and the acoustic receivers that track the salmon’s journey.

Dr Newton added: “Too many times, humanity has acted too late when a species is in decline.

“We have an opportunity to act now and make a lasting, positive impact so we’d ask everyone with an interest in preserving not only Scotland’s wild identity, but one of the world’s most famous species’ futures, to support this ground-breaking project.”