New Guinea flatworm: Foreign worm that could wipe out Britain’s snails arrives in Europe via potted plant imports

Experts want imports of pot plants banned to keep highly destructive species out of Britain

Environment editor

A A A

Imports of pot plants should be banned to keep out a highly destructive flatworm that threatens to wipe out the entire snail population, a top British insect expert has warned.

The New Guinea flatworm is set to become the latest “harmful non-native species” to enter Britain under the cover of plants brought in from abroad, after being spotted in Europe for the first time this month. Mr Shardlow said the rapid growth in international trade in potted plants had accelerated the spread of “harmful non-native species” as eggs and insects cross borders by passing under the radar in soil, foliage and branches.

“A flatworm that overwhelms snails in a ‘gang attack’ and has caused many extinctions when introduced to other parts of the world has now arrived in Europe. Urgent action is necessary to save wild British snails – the UK government should close the borders to pot plants,” he said. It is extremely difficult to detect eggs and small bugs in pots, which can be devastating when introduced to alien environments, wreaking havoc on gardens, forests, farmland and ecosystems by upsetting the balance of nature.

“It only takes one or two eggs in a pocket of air deep in the soil to survive and a potentially devastating invasive species has crossed over a border and threatens a new country, where there is no strategy to deal with the invader,” Mr Shardlow said.

“There is no need to import pot plants into the UK – horticulturalists here are quite capable of growing our own pot plants and selling them on the domestic market,” he added.

Potted plant trade is the likely source of species such as The New Zealand flatworm, which has significantly reduced worm populations in the northern British Isles, which play an essential part in aerating and fertilising the soil. Other examples include the Harlequin ladybird which consumes native ladybirds and the Spanish slug, which was first spotted in the UK last year, Mr Shardlow said. The Spanish species is larger, reproduces faster and is more resistant to slug pellets than UK species and is eating its way through gardens and crops. Concerns are mounting that it they could breed to produce a super-hybrid.

But the biggest fear surrounds the prospect of invasion by the New Guinea flatworm. “This species is extremely invasive. I really hope it can be stopped at the earliest stages,” said Jean-Lou Justine of the National Museum of Natural History in Paris, adding the threat was so great that “all snails in Europe could be wiped out”.

A government spokesman said: “We do not believe that there are any New Guinea flatworms in the UK but we are aware of the threat they could pose to our native wildlife. We are currently assessing the risk and will then consider the most appropriate action.”

Nor is the New Guinea flatworm the only vicious species poised to enter the UK via the international pot plant trade, Mr Shardlow warns. The Asian hornet, a bee-eating wasp already destroying bee populations is high on his list of insects to fear, as is the Argentine ant – “one of the worst invasive species in the world, eliminating native ant species and damaging ecosystem”.

Mr Shardlow is not alone in his concerns about harmful invasive non-native species. Graham Madge, of the RSPB, said: “We are extremely concerned about the threat of non-native species becoming established in the UK. This has very serious impact on wildlife and could be extremely damaging to the economy.”

“The problem is accelerating in line with international trade, partly because of the Internet which has significantly increased the volume of plants being shipped around the world,” he added.

Mr Madge says rising trade is part of a “potential nightmarish cocktail” – the other part being climate change, which makes it increasingly possible for invasive species such as termites to colonise the UK.

Invasive species fall into three broad categories, according to Mr Madge. There are those that come in “under the radar”, for example nestled in plant pots and  those – such as mink – that are brought into confined fur farms and escape and breed. Finally, there are those that are brought over and widely released and cause unintended problems – such as the grey squirrel, which was imported from American in the 19th century as a fashionable addition to estates and proceeded to the native grey squirrel population. Last week ministers finally conceded defeat in their battle against the grey squirrel by scrapping laws requiring people to report their presence on their land so they can be destroyed.

Robin Gill, a vertebrate ecologist at Forest Research, an agency of The Forestry Commission, put the damage inflicted by the grey squirrel on Britain’s timber industry at well over £10 million a year from bark stripping alone.

Those losses result from the lower price fetched by the damaged timber and is one of several reasons why woodland owners are increasingly unwilling to plant new trees, Mr Gill says.

“In the last year I have become increasingly aware of woodland owners not wanting to plant new trees because they feel it isn’t worth it.

“They are increasing worried about climate change, grey squirrels and a proliferation of diseases such as chalara fraxinea (ash dieback) because of the growing global trade in plants and plant products. These provide a strong disincentive to plant and the economic effects could be enormous,” he said.

Farmers are also concerned. “The changing climate means that species historically not able to reproduce in the UK, suddenly can do so,” said Guy Gagen, chief arable advisor at the National Farmers Union, noting that invasive species such ring rot in potatoes “can be very serious”.

Invasive non-native species cost the British economy an estimated £1.7 billion a year, most of it in agriculture and horticulture, according to a government report, which notes that the true cost is likely to be significantly higher because it doesn’t measure “damage to ecosystem services and loss of biodiversity, which cannot be readily quantified”.

Most experts agree that the threat posed by non-native species is clear. However, some believe there is some cause for hope, not least because the European Commission has acknowledged the scale of the threat and is working on “an action plan to protect biodiversity against problematic invasive species”.

“The country is under an unprecedented threat from tree pests and diseases after an exponential rise over the last decade. If we don’t do anything that rise will continue. But I am impressed by how everybody is recognising this as a problem and pulling together. Some things you can’t stop but others you can. So we face a big threat but it is possible to curb it,” said Ian Wright, the National Trust’s gardens advisor.

Britain’s deadly pot-plant bug imports

Harlequin ladybird (Harmonia axyridis) – It has taken less than five years to spread across the whole of the UK, consuming our native ladybirds and causing a nuisance in people’s houses in the autumn

Oak processionary moth (Thaumetopoea processionea) – strips whole oak trees bare of leaves leaving them vulnerable to attack from other pests and diseases. Has very irritating hairs that can cause skin rash for humans and stimulate the Forestry Commission into spraying woodlands with toxic pesticides that damage ecology.

New Zealand flatworm (Arthurdendyus triangulates) – a predator of our earthworms that has spread into the wild in parts of Northern England, Scotland and Northern Ireland. Its impacts have been particularly heavy on our most ecologically important earthworm the Lob worm.

Lily beetle (Liloceris lilii) – a shiny red beetle that people like until it eats all their lillies. They first came to Britain in the 1930s.

Spanish slug (Arion vulgaris): A huge slug spreading through Britain’s gardens and causing havoc. It is bigger and more resistant to slug pellets than UK species and the concern is that the two could breed to produce a super-hybrid slug.

Light brown apple moth (Epiphyas postvittana) – One of the commonest garden moths in many areas but the shiny orange-brown headed insect is so far only causing minor problems in the UK– imported from Australia.

Rosemary leaf beetle (Chrysolina Americana) – a frankly beautiful beetle, but not all rosemary growers agree with me. The beetle, which became an established pest in Britain in the 1990s, also eats the leaves of lavender, thyme and sage.

And three to beware of

New Guinea flatworm (Platydemus manokwari): A horror that has destroyed populations of native snails across the Indo-Pacific that has just been found in Europe for the first time, in France. It is considered to be the cause of extinction of native land snails on several Pacific and Pacific Rim islands.

Asian hornet (Vespa velutina) – a bee-eating wasp already destroying bee populations in France. It is expected to cross into the UK, initially settling in the southern parts of the country. It is regarded as a highly effective predator of insects, posing a significant threat to ecosystems.

Argentine ant (Linepithema humile) – one of the worst invasive species in the world, eliminating native ant species and damaging eco-systems. Its workers are extremely fast moving and industrious, often recruiting in high numbers.

Travel
travel
Arts and Entertainment
The cast of The Big Bang Theory in a still from the show
tvBig Bang Theory filming delayed by contract dispute over actors' pay
Sport
England celebrate a wicket for Moeen Ali
sportMoeen Ali stars with five wickets as Cook's men level India series
News
Morrissey pictured in 2013
people
PROMOTED VIDEO
Have you tried new the Independent Digital Edition apps?
Voices
A family sit and enjoy a quiet train journey
voicesForcing us to overhear dull phone conversations is an offensive act, says Simon Kelner
News
peopleGuitarist, who played with Aerosmith, Lou Reed and Alice Cooper among others, was 71
Travel
travel
News
Robyn Lawley
people
News
people
News
i100  ... he was into holy war way before it was on trend
Arts and Entertainment
High-flyer: Chris Pratt in 'Guardians of the Galaxy'
filmThe film is surprisingly witty, but could do with taking itself more seriously, says Geoffrey Macnab
News
people
Life and Style
food + drinkVegetarians enjoy food as much as anyone else, writes Susan Elkin
Life and Style
lifeDon't get caught up on climaxing
Life and Style
tech
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
iJobs Job Widget
iJobs General

1st line call logger/ User access administrator

£9 Per Hour: Clearwater People Solutions Ltd: Our client based in Warrington a...

Shine Night Walk 2014 - 'On the night' volunteer roles

Unpaid Voluntary Work : Cancer Research UK: We need motivational volunteers to...

Accounts Assistant (Accounts Payable & Accounts Receivable)

£23000 - £25000 per annum: Ashdown Group: Accounts Assistant (Accounts Payable...

Senior IT Trainer - Buckinghamshire - £250 - £350 p/d

£200 - £300 per day: Ashdown Group: IT Trainer - Marlow, Buckinghamshire - £25...

Day In a Page

Save the tiger: The day America’s love of backyard tigers led to a horrific bloodbath

The day America’s love of backyard tigers led to a horrific bloodbath

With only six per cent of the US population of these amazing big cats held in zoos, the Zanesville incident in 2011 was inevitable
Samuel Beckett's biographer reveals secrets of the writer's time as a French Resistance spy

How Samuel Beckett became a French Resistance spy

As this year's Samuel Beckett festival opens in Enniskillen, James Knowlson, recalls how the Irish writer risked his life for liberty and narrowly escaped capture by the Gestapo
We will remember them: relatives still honour those who fought in the Great War

We will remember them

Relatives still honour those who fought in the Great War
Star Wars Episode VII is being shot on film - and now Kodak is launching a last-ditch bid to keep celluloid alive

Kodak's last-ditch bid to keep celluloid alive

Director J J Abrams and a few digital refuseniks shoot movies on film. Simon Usborne wonders what the fuss is about
Once stilted and melodramatic, Hollywood is giving acting in video games a makeover

Acting in video games gets a makeover

David Crookes meets two of the genre's most popular voices
Could our smartphones soon be diagnosing diseases via Health Kit and Google Fit?

Could smartphones soon be diagnosing diseases?

Health Kit and Google Fit have been described as "the beginning of a health revolution"
Ryanair has turned on the 'charm offensive' but can we learn to love the cut-price carrier again?

Can we learn to love Ryanair again?

Four recent travellers give their verdicts on the carrier's improved customer service
Billionaire founder of Spanx launches range of jeans that offers

Spanx launches range of jeans

The jeans come in two styles, multiple cuts and three washes and will go on sale in the UK in October
10 best over-ear headphones

Aural pleasure: 10 best over-ear headphones

Listen to your favourite tracks with this selection, offering everything from lambskin earmuffs to stainless steel
Commonwealth Games 2014: David Millar ready to serve up gold for his beloved Scotland in the end

Commonwealth Games

David Millar ready to serve up gold for his beloved Scotland in the end
UCI Mountain Bike World Cup 2014: Downhill all the way to the top for the Atherton siblings

UCI Mountain Bike World Cup

Downhill all the way to the top for the Atherton siblings
Save the tiger: The animals bred for bones on China’s tiger farms

The animals bred for bones on China’s tiger farms

The big cats kept in captivity to perform for paying audiences and then, when dead, their bodies used to fortify wine
A former custard factory, a Midlands bog and a Leeds cemetery all included in top 50 hidden spots in the UK

A former custard factory, a Midlands bog and a Leeds cemetery

Introducing the top 50 hidden spots in Britain
Ebola epidemic: Plagued by fear

Ebola epidemic: Plagued by fear

How a disease that has claimed fewer than 2,000 victims in its history has earned a place in the darkest corner of the public's imagination
Chris Pratt: From 'Parks and Recreation' to 'Guardians of the Galaxy'

From 'Parks and Recreation' to 'Guardians of the Galaxy'

He was homeless in Hawaii when he got his big break. Now the comic actor Chris Pratt is Hollywood's new favourite action star