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20 May, 2014

Battle to keep Scottish waters free from invasive species

The battle to keep invasive non-native marine species under control is stepping up a notch, with the publication of ground-breaking guidance, the first of its kind for the UK

More than 90 marine invasive non-native species have been identified in British and Irish waters, of which 17 are now established in Scotland.

The Firth of Clyde Forum, in partnership with Scottish Natural Heritage (SNH), have created the guidance, which gives marine businesses and other marine site managers easy-to-follow procedures for creating a biosecurity plan. The plan will then help to reduce the threat of moving and introducing new species to their site. The forum has also produced a handy, pocket-sized identification guide and an online reporting system for anyone using our waterways. The pocket guide encourages people to take a photo of anything unusual with their mobile phones and send the pictures to a website where an expert will identify it for them. If the species is identified as being of high concern, then it will automatically be prioritised for action by the authorities.

The invasive creatures, which often sound like something out of a science fiction novel, can destroy local species and habitats, affecting the food chain and biodiversity and leading to massive financial costs for fisheries and other leisure and commercial marine operations. These globetrotters get to Scottish waters from the other side of the world by hitching a ride on hulls of boats or in their ballast water. Some can even survive for several days out of water on damp water-sports gear.

Species such as invasive carpet sea squirts like Didemnum vexillum, a fast-growing animal which smothers underwater structures, plants and animals, are already present in Scotland. This sea squirt was first reported in the UK in 2008, and has been found in several sites in the Clyde. Other species include the Mitten Crab which can destroy bankside habitats with their destructive burrowing, and the Zebra Mussel which grows at an astonishing rate and can quickly clog water intakes and block canal gates.

Freshwater species, such as Killer Shrimp can also be a massive problem: these small creatures have voracious appetites and have munched their way through the rivers systems of Europe devouring native invertebrates, fish eggs and fry. They have not yet been found in Scotland, but are considered a high risk.

The guidance gives detail on the steps a company should take to prevent and control the movement of any invasive species. The guidance has been so well received that it now has also been picked up by other UK agencies, including Natural England and Natural Resources Wales.

Sarah Brown, Project Manager of the Firth of Clyde Forum, said:

"It's a continual struggle to keep these invasive species, such as the carpet sea squirt, from spreading in Scottish waters. Our seas are important in so many ways for both the environment and economy. So it's crucial that anyone who gets afloat for fun or whose livelihood relies on the water is aware of the issue and taking action, either by creating and following a biosecurity plan or by reporting any sightings of unusual species."

Stan Whitaker, SNH's invasive non-native species expert, added:

"I'd encourage boaters to keep a copy of the easy-to-use, pocket-sized ID guide handy and report any unusual sightings. The new guidance on biosecurity planning is arguably the best of its kind in Europe, but we still need to be vigilant. Once established, it's particularly hard to control the spread of marine species. Invasive non-native species are the second most serious threat to global biodiversity after habitat loss, with non-native species costing the Scottish economy around £246 million each year."

Using the biosecurity planning guidance can help organisations avoid prosecution and the financial cost if something does go wrong: it's now an offence to introduce INNS to Scottish waters through commercial or recreational marine activities, even if the introduction was unintentional. Using the guidance to create a biosecurity plan also highlights a business's green credentials in responding responsibly to a serious environmental threat.

The guidance, along with a review of marine biosecurity best practice literature, was produced by SAMS Research Services Ltd (SRSL), a specialist marine consultancy with unique expertise in advising businesses on preparing and implementing marine biosecurity plans.

Dr Adrian Macleod of SRSL said:

"Whether you're a boater, a marina or a harbour authority, the responsibility for your impact on the marine environment lies with you. The biosecurity planning guidance makes it straightforward for those using Scottish waters to assess and reduce the risk of spreading invasive non-native species."

Download the Marine Biosecurity Guidance at

Download the pocket guide and other invasive, non-native species information at

Download the report, Marine biosecurity planning - Identification of best practice, at

Notes to editors

To download more pictures of invasive non-native species, go to

The Firth of Clyde Forum is a voluntary partnership of local authorities, organisations, businesses and communities committed to working towards integrated, sustainable management of the Clyde's environmental, economic and community resources. For more information about the Firth of Clyde Forum, visit and

Invasive Non-native Species (INNS) are plants and animals that have been introduced to waters outside their natural range by human action. Human activities such as increased international trade have led to a dramatic increase in the numbers of INNS. The heaviest hit marine industries include aquaculture, fisheries, power generation and shipping.

The Marine Biosecurity guidelines were commissioned by the Firth of Clyde Forum and SNH in response to recent changes to the Wildlife and Natural Environment (Scotland) Act 2001. The legislative changes empower government agencies to serve Voluntary, Statutory and finally Emergency Species Control Orders (SCOs). Where offences occur, measures taken to eradicate INNS will be financed on a Polluter Pays Principal', which has the potential to be costly for small businesses, which could be temporarily shut down and be charged for imposed clean-up operations.

Contact information

SNH Media

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