IT’S found in natural abundance around Scotland and was once the crop that powered the long-gone kelp industry on the Western Isles.

Now seaweed cultivation could again become a real cash-earner in Scotland, the rest of the UK and Europe – but only if it becomes a sustainable industry and avoids over-cultivation and disease.

For a team of Scottish scientists has just issued a strong warning to the rapidly expanding global seaweed industry that it must avoid the mistakes made on land by farmers and at sea by fish farming companies.

Based near Oban and founded in 1884, the Scottish Association for Marine Science (SAMS) is leading a 21-institution international team in world-beating research aimed at preserving and growing the global seaweed industry.

In a report published by United Nations University’s Canadian-based Institute for Water, Environment and Health (UNU-INWEH ) and SAMS, the industry is warned that it needs to guard against non-indigenous pests and to raise awareness of mistakes in farm management practices.

The authors added: “In addition, the illegal use of algicides/pesticides, with unknown but likely detrimental consequences for the wider marine environment, user conflicts for valuable coastal resources and rising dissatisfaction over the low gate prices for the crop can all result in negative impacts on the industry.”

The warning comes as the UK Government’s Department for Environment, Food and Rural Affairs (DEFRA) has called for a network of seaweed farms to satisfy growing demand.

Marine biologist Dr Craig Rose, managing director of the specialist firm Seaweed and Co., told a newspaper: “There is huge scope for seaweed production in this country as it’s local, natural and sustainable.

“But it needs to become mainstream with consumers. It’s like houmous. Years ago, very few people knew what it was – now it’s a big seller.

“If we scaled up production, it could also become viable for biofuel for electricity, heating and fuel for cars. We could establish a new industry within two years.”

Last year SAMS began its own experimental seaweed farm in a bid to see whether Scotland could join those countries such as China, the Republic of Korea, Indonesia, the Philippines and Japan which are producing the vast majority of seaweed for human consumption.

In 2014, China alone produced 12.8 million tonnes of seaweed, or 54 per cent of total global production, followed by Indonesia with 6.5 million tonnes, 27.4 per cent of world production.

The new SAMS-led report states that seaweed “is widely perceived as one of the most environmentally benign types of aquaculture activity, as it does not require additional feed or fertilisers.”

The report added: “In the last decade, seaweed cultivation has been expanding rapidly thanks to growing demand for its use in pharmaceuticals, nutraceuticals and antimicrobial products, as well as biotechnological applications.

“Seaweed today is used in some toothpastes, skincare products and cosmetics, paints and several industrial products, including adhesives, dyes and gels. Seaweed is also used in landscaping or to combat beach erosion.”

There can be a downside, however. The report stated: “Communities that come to depend on a single crop for their livelihood become highly vulnerable to a disease outbreak, as happened in the Philippines between 2011 and 2013 when a bacteria that whitens the branches of a valuable seaweed species caused a devastating loss to the communities involved, estimated at over $310 million.”

Lead author Elizabeth J Cottier-Cook of SAMS said: “Rapidly increasing seaweed cultivation globally will be good for commerce and open up a range of new products, but we must also try to minimise any negative effects this industry may have on coastal marine environments.

“The seaweed industry must be developed in a sustainable way that considers not just how to maximise profits but maintain the highest biosecurity standards to prevent pests and disease. It will also be crucial to develop new indigenous disease-resistant strains of seaweed.”

Vladimir Smakhtin, Director of UNU-INWEH, said: “The growth of the seaweed industry in the past half century constitutes an important success story and it continues to expand to the benefit of some of the world’s most impoverished people. But the industry needs to learn fast from other sectors to ensure it remains sustainable.”

Nicholas Owens, director of SAMS, said: “The seaweed industry in Asia has been growing rapidly for the best part of 60 years, but Europe has only recently woken up to the economic potential of seaweed cultivation.

“Interest in the West has been sparked by the wide range of seaweed applications, from health foods through to fuel, that can be produced in a sustainable way and has little environmental impact. As the only marine science institute to have associated institute status with the UNU, we are proud to be involved with helping to lead the discussion on this increasingly important topic.”