Offshore wind farms will test the survival skills of salmon

Offshore wind farms are the latest barrier for salmon returning home

The route home for Scottish salmon is due for disruption. Soon our great fish will face a formidable assemblage of new obstacles, both at homecoming and at emigration.

The largest is the 200-plus wind turbine array planned for the middle of the Outer Moray Firth. Salmon and sea-trout from 14 rivers use this firth and there are also concerns for migrating fish, including protected eels and lampreys. They will face construction disturbances, water-column tremors from the shuddering towers, and for sensitive fish, the effects of electro-magnetic fields. Remember, the young salmon smolts negotiating these new industrial obstacles are just six inches long.

The Scottish Government’s reaction to these worries is a promise to monitor the effects. Aside from the fact that monitoring would measure effects posthumously rather than ensure safe passage at the outset, the issue for adult salmon finding home rivers will neither be addressed nor monitored. Indeed, it is difficult to see how it would be possible to do so.

So far the monitoring undertaken has been of the passage of smolts, tagged with devices meant to trigger responses from land-based acoustic receivers. However, according to Marine Scotland, background noise spoiled the experiment. Any usable data will be available later this year. So in short, the wind farm will be built regardless of the effect it will have on salmon and sea-trout.

In another initiative, underwater turbines are being moored on the sea-bed of the Pentland Firth, the location of fantastically rich marine life. This is where the halibut are so big, some over 200 kilos, that two men have to sit on the fish for the filleters to cut out choice parts. The turbines will, in theory, use the famously ferocious currents of the firth to make tidal energy. Where do salmon fit in? Effects – you guessed right – will be monitored. In place of duty of care, reassurances.

What if salmon and sea-trout falter? If monitoring showed that migrating salmon couldn’t interact with the new wave energy models, would the industrial plant be deconstructed in favour of the natural ecology? Project costs can run into billions of pounds. Salmonids, as ever, have to circumvent human development. Government concern is purely cosmetic.

Scottish salmon survival skills are already at full stretch. Despite the horrors recently afflicting Scottish salmon farms – 100,000 salmon were boiled alive in sea-louse treatments which required water too hot for the fish to withstand – the Scottish Government has plans to double Scottish aquaculture output by 2030. The logic seems to be, if an industry is pushing the edges of the envelope, boost it.

How much of the increase will comprise salmon – which are now being fed poultry remains in a further lurch towards foodchain distortion–and how much will consist of mussel-ropes and the like is unknown. What is clear is that the government is happy to attach its colours to the out-ofsight out-of-mind aquaculture industry as a lifeline for its own credibility. The cost of the premature cooking of the farmed salmon was £2.7 million.

Another 60,000 were inadvertently killed by chemicals designed to destroy amoebic gill disease and elsewhere 20,000 fish were killed by mistake. If salmon farmers paid the environmental levies and fines which farmers on land have to they would have been bust long ago.

It’s curious to consider that when it was shown back in the 1970s that Atlantic salmon could be farmed in sea cages, it was the species’ amazing adaptability and flexibility which allowed for its successful intensive rearing. Other fish, like halibut, even Pacific salmon, were too difficult. The possibility of mass parasite attacks were not on the radar. Vast industrial developments blocking wild salmonid migration routes were not envisaged either.

Maybe today we are seeing the limits of our salmon’s innate resistance being tested beyond endurance.

‘ Salmonids, as ever, have to circumvent human development’


MAR 1 2017
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