Ilona Amos: Unbridled expansion of fish farms is not sustainable

Scotland has an international reputation for high quality food and drink. Our fish is no exception and some parts of the world have a seemingly insatiable appetite for Scottish-reared salmon.

Scotland is the EU's leading produced of farmed salmon, with plans to step up production by 30,000 tonnes by 2020. Picture: Stephen Mansfield

Norway is currently responsible for producing a third of all farmed salmon in the world, with Chile close behind at 31 per cent and other European countries at 19 per cent. But despite its small stature, Scotland is now the largest producer in the EU.

We have come a long way since the first forays into fish farming in the late 1960s. The inaugural harvest in 1971 was 14,000 tonnes. Compare that to record production figures seen in 2014, when nearly 180,000 tonnes were produced.

Farmed salmon is one of our most important exports, distributed to more than 50 countries and estimated to be worth £1.86 billion to the economy. The Scottish Government has set out plans to “sustainably” increase production to 210,000 by 2020 to take advantage of rising demand from abroad.

There are already about 250 farm sites off the coast of Scotland and its islands. Can this massive expansion actually be done in a way that is not damaging?

Scottish aquaculture suffers particularly badly from infestations of sea lice, which are estimated to cost the industry £30 million a year and make the sector less profitable here than in other parts of the world.

The most recent figures show the tonnage of salmon produced in Scotland in 2015 was four per cent lower than the year before – a drop blamed on sea lice, which injure and often kill the host fish. Industry giant Marine Harvest estimates that it may have lost around 1,500 out of 40,000 tonnes of fish produced last year because of the parasite, which can spread from captive fish to wild salmon and sea trout with devastating effects on declining populations.

There are also other concerns over fish farms, including the effects of huge quantities of fish sewage and uneaten food being released into the sea. Fears have also been raised over the potential repercussions on other marine organisms – and even human health – of a massive rise in the use of chemicals and medicines to treat pests and diseases in farmed fish.

Plans to establish a large new salmon farm in a stretch of water identified as internationally important for its sea life has sparked an impassioned backlash from members of the public.

If it gets the go-ahead, the 12-cage facility will rear more than one million fish off the coast of Dounie, in the Sound of Jura – within an area set aside to protect the threatened common skate.

A new campaign group, Friends of the Sound of Jura, has been formed to fight the plans and an online petition has already attracted more than 200 signatures. Protesters claim the farm would discharge huge amounts of organic waste, mainly faeces, into the sea, as well as toxic chemicals, creating dead-zones and encouraging potentially harmful algal blooms. There is also the risk of escapees.

It’s not just the environmental impacts of fish farms that beg a closer look. There can be negative effects on other rural industries such as creel fishing and diving, leisure and tourism.

Despite the 2015 fall in production, the industry is predicting 2016 figures will show an uplift. Meanwhile, the big salmon producers have their eyes on the prize and are storming towards that 2020 target. Expansion plans set out in the past month alone would see capacity increase by in excess of 15,000 tonnes a year.

But surely we must sort out the problems at hand instead of pushing exploitation of sites that are worth more than their weight in fish.