Wandle Restoration Part XV

May 11, 2012

by Theo Pike

Aliens 1

In the six years since I started writing this once-regular monthly column (not to mention the five – where have they gone? – that somehow seem to have elapsed since I released that last tankful of little brown trout into the headwaters of the Wandle) a lot has happened in the world of river restoration.

Subjects that once seemed the exclusive preserve of environmental consultants, and a very few out-there restorationists, have now become almost-daily talking points on forums, blogs and podcasts. Angling club AGMs are peppered with debates on trout genetics and the benefits of large woody debris, and the Wild Trout Trust’s growing team of Conservation Officers is running hot on Advisory Visits up and down the land. And it’s reassuring to see that one final topic is also gaining ground: biosecurity and the importance of protecting our river systems’ biodiversity from damage by invasive non-native species (INNS).

For salmon fishers on regular loops of pilgrimage between Scotland, Norway and Iceland, biosecurity measures to guard against Gyrodactylus salaris is nothing new. Amongst ecologists, examples of invasive species like brown trout and ‘rock snot’ in New Zealand, cane toads in Australia and purple loose strife across the eastern seaboard of the USA have almost become clichés: one of my favourite environmental writers, David Quammen, tapped out his ‘Planet of Weeds’ essay for Harpers’ Magazine all the way back in 1998, and I still scan my dog-eared print-out once a year to check how many of his predictions are slowly coming true.

But even for those who haven’t noticed our sport being directly threatened by alien algae and invertebrates, the days of reckoning seem to be drawing closer.

In autumn 2010, fear of aquatic INNS hit Britain’s national headlines when the colourfully-nicknamed ‘Killer Shrimp’ were found in Cardiff Bay, Grafham and Eglwys Nunnyd reservoirs. By spring 2012 they’d spread to the Norfolk Broads: today, every riverfly monitoring team in the country is alive to the possibility that their river could be next, even if the shrimp’s mode of transmission remains unclear.

In straitened economic times, financial factors have focused people’s minds and public policy alike: the cost of removing and disposing of Japanese knotweed from the Olympic Park in East London has been estimated at £70 million, and DEFRA’s own estimate suggests that it could cost up to £300 million to eradicate Himalayan balsam from the whole of the UK. So legislation is catching up too. The Wildlife and Countryside Act of 1981 listed only giant hogweed and Japanese knotweed as species banned from release into the wild – but an updated schedule of 36 new plants was added in 2010, identifying water fern, Australian swamp stonecrop, water hyacinth, floating pennywort, Himalayan balsam, water primrose and parrot’s feather as invasive non-native species requiring special control. And certainly no day-releases from goldfish bowls and garden ponds…

In the wake of these new regulations – plus public-information drives like DEFRA’s ‘Be Plant Wise’ gardeners’ awareness campaign, which was launched on the Wandle in March 2010, and DEFRA-sponsored invasive species action plans – it’s fair to say that society in general is becoming more conscious of the problems presented by invasive aliens.

But as responsible anglers there’s probably always more we can do, and one very personal way we can help is by promoting – and following! – the recommendations of the Check Clean Dry campaign. Devised last year by a partnership of water stakeholders’ groups including the Angling Trust, Canoe England, British Rowing, the Environment Agency and the Rivers Trusts, this is a suite of biosecurity recommendations that are well worth quoting in their entirety, if only to make sure we’re helping to solve a growing problem rather than being part of it every time we step into (or out of) a river or lake:

Check

• Check you are not unknowingly carrying any water, living organism (including plant fragments) on your equipment or clothing
• Pay particular attention to those areas that retain water, remain damp or are hard to inspect

Clean

• Clean equipment, footwear and clothes thoroughly after water-based activity
• Pieces of plants, seeds and organisms that get caught up in, or attach themselves to your equipment must be thoroughly removed from all hulls, hidden corners, inside clothing and other surfaces
• Where available, use pressure washers and hoses to wash equipment and clothing
• Ensure washings and any water that has collected in equipment are left in the cleaning area. Alternatively, empty them onto land away from other watercourses and not into another watercourse, drain or ditch

Dry

• All equipment and clothing should be dried thoroughly
• Where possible, air dry for 48 hours in order to kill any aquatic organisms
• In slightly moist conditions, some species can live for many days

Now, I’ll be the first to admit that these aren’t always easy in practice. For instance, how can you be sure of drying the dense fabric of your wading boots between fishing the morning and evening hatches on different rivers in the course of a multi-day road trip – especially when even industry leaders like Simms can’t seem to tell a consistent story on the biosecurity risks of felt soles from one season to the next?

But gnarly as they are, trying to take these relatively small precautions could make all the difference to our rivers’ future and the fundamental sustainability of our sport. And when the EA’s latest research shows that “a killer shrimp can survive in the moist fold of a wader for up to 15 days”, that’s not something we can lightly ignore…

In a few weeks’ time I’ll be back with more details of the most threatening invasive non-native plants and animals, and what you can do to stop them in their tracks. And in the meantime, Check Clean Dry posters are freely available to download from the GB Non-Native Species Secretariat’s website… so why not start spreading ‘em round your fishing pals today?

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