Discovery of 'killer' shrimp alarms experts

For the first time the vicious shrimp
Dikerogammarus villosus has been found in Britain, causing consternation among scientists charged with keeping the country's waterways stocked with native wildlife.

Visually, the brown crustacean may not inspire in the public the terror generated by more fearsome monsters of the deep, but a hint of the menace scientists say it is capable of can be gleaned from its nickname: the killer shrimp.

A particularly voracious and aggressive predator, Dikerogammarus villosus preys on a range of invertebrates, particularly native shrimps and young fish, sometimes causing their extinction. It tends to dominate its habitat, killing and maiming unselectively.

Its aggression – it bites and shreds its prey to death but often leaves it uneaten – is matched by its versatility, and it can survive fluctuations in temperature, salinity and oxygen levels. As a result its numbers have grown rapidly in the long rivers of western Europe in the past 20 years, damaging smaller species and ruining ecological chains.

On Friday two anglers spotted unusual-looking shrimps scuttling along Grafham Water reservoir in Cambridgeshire, captured some specimens and sent them to the Environment Agency.

A preliminary identification of Dikerogammarus villosus was made – later confirmed by a Dutch scientist – prompting a full-scale alert. The agency contacted Anglian Water, the owner of Grafham, and began measures to survey and halt the shrimp's presence.

Expert biologists have begun testing the water flowing into and out of Grafham, which will indicate the severity of the problem and what measures need to be taken. Signs have also been erected asking anglers, boaters and other water users to look out for the shrimp and to scrub their rods, boats and other apparatus to ensure they do not carry it unwittingly into other water.

Dr Paul Leinster, the Environment Agency's chief executive, said: "We are devastated that this shrimp has been found in Britain, and very grateful to the keen-eyed anglers who found it.

"We are currently establishing the degree of the problem, and whether the shrimp is only in Grafham Water or if it is in nearby lakes and the Great Ouse as well."

Scientists will have to look closely because the shrimp is small, ranging from 3mm to 30mm. Despite its small size, if the shrimp becomes established in Britain, the Environment Agency fears it could soon start swallowing natives species common on lakes and rivers, such as native damselflies and water boatmen, with knock-on effects on the species which feed on them – birds, spiders and frogs.

Ciaran Nelson, from Anglian Water, said: "We have put precautionary biosecurity measures in place around Grafham Water as containing the shrimp is of paramount importance. We are also assisting with investigations to establish if it is already more widespread. The presence of this species poses no risk to the quality of drinking water supplies.

"We are asking all water users at Grafham to take the actions asked of them on-site. This includes checking equipment for shrimp when they leave the water and removing any they find. They should also ensure equipment is thoroughly cleaned and dried before it is put into any other water. Subject to these controls, recreational activities on the reservoir can continue."

The Environment Agency said the shrimp could have arrived at Grafham in various ways, for example through boating, angling, fish-stocking – or naturally, via birds. Its progress through western Europe has been rapid. Populations in the Black Sea rivers had spread northwards and westwards into the German Danube by 1992, since when it has spread into other German rivers such as the Rhine and Elbe, and the Rhone in France.

Alarm about its arrival has reached the upper echelons of Whitehall. The Environment Minister, Richard Benyon, said he was "extremely concerned" it had been found. "Anglian Water has acted quickly to put biosecurity measures in place and the Environment Agency is working hard to establish the extent of the problem and what action may need to be taken," he said.

"We need to do everything we can to protect our native wildlife and young fish from the potential damage the killer shrimp can cause."

Water users at Grafham who want information on the measures they can take to combat the spread of the shrimp can contact Anglian Water on 08457 919155.

Anyone who has seen "an unusual shrimp" is asked to email a photograph to the Centre for Ecology & Hydrology for identification. The address is:

Invasive species...

American signal crayfish

Native to North America, signals carry a disease, crayfish plague, that is deadly to our threatened native white-claw crayfish. Since their introduction to Britain in the Seventies, they are now widespread throughout Europe.

Non-native American mink

Brought to the UK in the 1920s for fur farms. After several escapes it quickly established itself in the English countryside, becoming the main predator of the native water vole (Ratty in The Wind in the Willows), whose numbers have fallen by more than 90 per cent in 50 years, partly because of predation by mink.

Floating pennywort

After being introduced as an aquatic garden plant in the Eighties, this 'water triffid' soon went wild. It grows in huge, dense mattresses that choke waterways, starving the water of light, oxygen and nutrients.

Topmouth gudgeon

It may be less than three inches long, but this invader from Asia preys on the eggs of native fish, breeds fast and spreads disease.

Chinese mitten crabs

This Asian species has made its home in some UK fresh waters, including the Thames. It damages riverbanks by burrowing into them, and out-competes native species.

Suggested Topics
Arts and Entertainment
Sydney and Melbourne are locked in a row over giant milk crates
Kenny Ireland, pictured in 2010.
peopleActor, from House of Cards and Benidorm, was 68
A scene from the video shows students mock rioting
newsEnd-of-year leaver's YouTube film features staging of a playground gun massacre
A family sit and enjoy a quiet train journey
voicesForcing us to overhear dull phone conversations is an offensive act, says Simon Kelner
i100This Instagram photo does not prove Russian army is in Ukraine
Morrissey pictured in 2013
sportVan Gaal has £500,000 video surveillance system installed to monitor Manchester United players
View from the Llanberis Track to the mountain lake Llyn
Du’r Arddu
environmentA large chunk of Mount Snowdon, in north Wales, is up for sale
Life and Style
Martha Stewart wrote an opinion column for Time magazine this week titled “Why I Love My Drone”
lifeLifestyle guru Martha Stewart reveals she has flying robot... to take photos of her farm
Arts and Entertainment
The Secret Cinema performance of Back to the Future has been cancelled again
filmReview: Sometimes the immersive experience was so good it blurred the line between fiction and reality
ebookA unique anthology of reporting and analysis of a crucial period of history
Life and Style
The director of Wall-E Andrew Stanton with Angus MacLane's Lego model
gadgetsDesign made in Pixar animator’s spare time could get retail release
peopleGuitarist, who played with Aerosmith, Lou Reed and Alice Cooper among others, was 71
Tyred out: should fair weather cyclists have a separate slow lane?
environmentFormer Labour minister demands 'pootling lanes' for women cyclists
Travel Shop
the manor
Up to 70% off luxury travel
on city breaks Find out more
Up to 70% off luxury travel
on chic beach resorts Find out more
sardina foodie
Up to 70% off luxury travel
on country retreats Find out more
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

VB.Net Developer - £40k - Surrey - WANTED ASAP

£35000 - £40000 per annum + competitive: Progressive Recruitment: .Mid Level V...

Digitakl Business Analyst, Slough

£40000 - £45000 per annum + Competitive Benefits: Progressive Recruitment: Dig...

Mechanical Estimator: Nuclear Energy - Sellafield

£40000 - £50000 per annum + Car, Medical, Fuel + More!: Progressive Recruitmen...

Dynamics NAV Techno-Functional Consultant

£50000 - £60000 per annum + benefits: Progressive Recruitment: An absolutely o...

Day In a Page

Dress the Gaza situation up all you like, but the truth hurts

Robert Fisk on Gaza conflict

Dress the situation up all you like, but the truth hurts
Save the tiger: Tiger, tiger burning less brightly as numbers plummet

Tiger, tiger burning less brightly

When William Blake wrote his famous poem there were probably more than 100,000 tigers in the wild. These days they probably number around 3,200
5 News's Andy Bell retraces his grandfather's steps on the First World War battlefields

In grandfather's footsteps

5 News's political editor Andy Bell only knows his grandfather from the compelling diary he kept during WWI. But when he returned to the killing fields where Edwin Vaughan suffered so much, his ancestor came to life
Lifestyle guru Martha Stewart reveals she has flying robot ... to take photos of her farm

Martha Stewart has flying robot

The lifestyle guru used the drone to get a bird's eye view her 153-acre farm in Bedford, New York
Former Labour minister Meg Hillier has demanded 'pootling lanes' for women cyclists

Do women cyclists need 'pootling lanes'?

Simon Usborne (who's more of a hurtler) explains why winning the space race is key to happy riding
A tale of two presidents: George W Bush downs his paintbrush to pen father’s life story

A tale of two presidents

George W Bush downs his paintbrush to pen father’s life story
Restaurateur Mitch Tonks has given the Great Western Pullman dining car a makeover

The dining car makes a comeback

Restaurateur Mitch Tonks has given the Great Western Pullman dining car a makeover
Gallery rage: How are institutions tackling the discomfort of overcrowding this summer?

Gallery rage

How are institutions tackling the discomfort of overcrowding this summer?
Louis van Gaal has £500,000 video surveillance system installed to monitor Manchester United players

Eye on the prize

Louis van Gaal has £500,000 video surveillance system installed to monitor Manchester United players
Women's rugby: Tamara Taylor adds fuel to the ire in quest to land World Cup

Women's rugby

Tamara Taylor adds fuel to the ire in quest to land World Cup
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