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Killer shrimp ALERT

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Government advice on invasive aquatic species This government campaign on biosecurity is coordinated by DEFRA. DEFRA is working with statutory bodies, partners and stakeholders via various working groups in direct action to prevent the spread of the killer shrimp. See presentation by Mark Diamond, Environment Agency 'Our response to the arrival of the invasive shrimp' at the Riverfly Partnership Conference Your rivers - their future, 10 March 2011 Please circulate the notification and identification sheet below as widely as possible. Stop the spread –PDF-File, 268.5 KB Notice for fishing huts / clubs –PDF-File, 16.1 KB Killer shrimp identification sheet (Freshwater Biological Association) –PDF-File, 596.6 KB Killer shrimp information (Non Native Species Secretariat) –PDF-File, 298.1 KB

Riverfly Partnership action

RP Partners, The Angling Trust (AT), Salmon and Trout Association (S&TA), Freshwater Biological Association, Aquascience, Buglife and others are working with the statutory bodies regarding biosecurity measures, current status, surveys, research and risk. Contact: Mark Owen (AT) or Janina Gray (S&TA) for further information. The Riverfly Partnership call Anglers' Riverfly Monitoring Initiative (ARMI) Groups and partners to be vigilent in looking out for this species. ARMI involves trained volunteer groups regularly monitoring the biological water quality of their rivers, specifically the abundance of riverflies and gammarus, to help protect river health. Size and colour are useful aids to identification of this species, with the projections on the lower body being definitive features. Refer to the Freshwater Biological Association identification sheet. If you find the Killer shrimp, send a photo and details of location, together with your contact details to Help stop the spread of non native species. Always: - Inspect and clean launching trailers, boats and kit before and after use - Drain all bilge water from boats before leaving sites - Disinfect angling kit before use. Hang all equipment to dry for a minimum of 48hrs before visiting new venues - Ensure no lake water is taken away with your kit - Avoid the transfer of bait between water bodies.

Killer Shrimp found at 2 sites in Wales. Update November 2010

The Killer Shrimp has now been recorded at 2 sites in South Wales. The Riverfly Partnership urge all to take action as below. The Riverflly Partnership are working with Invertebrate Link, Freshwater Biological Association, Buglife, Angling Trust, Salmon and Trout Association and The Environment Agency and will post updates here.

ALERT - KILLER SHRIMP Dikerogammarus villosus September 2010

The Killer shrimp, Dikerogammarus villosus, a highly invasive non-native species was found for the first time in the UK in Grafham Water, an Anglian Water reservoir, in Cambridgeshire on 3 September 2010. This voracious predator is a threat to a range of native species, including young fish and invertebrates and significantly alters ecosystems. This is the first known outbreak of the Killer shrimp in UK - it is vital that we stop its spread to new locations. The Riverfly Partnership is calling for your action. Two keen-eyed anglers spotted the unusual shrimp, which can be as small as 3mm, and sent samples to the Environment Agency for identification. There is widespread concern regarding the threat of this species to our freshwater habitats and native species. Native to south-eastern Europe, the species has recently spread to western Europe. Defra Minister, Richard Benyon: ‘I am extremely concerned to hear that this highly invasive species has been found in Britain. 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. We need to do everything we can to protect our native wildlife and young fish from the potential damage the killer shrimp can cause.’ Briefing Note EA NE 11 October 2010 –PDF-File, 82.1 KB

Further information

Environment Agency press release, 9 Sept 2010: Killer shrimp found in the UK for the first time Non Native Species Secretariat Freshwater Biological Association Anglian Water

Frequently asked questions - Environment Agency September 2010

What is the Killer shrimp? The Killer shrimp Dikerogammarus villosus is an invasive non-native species that has spread from the Ponto-Caspian Region of Eastern Europe – it is native to the Black Sea and the Caspian Sea. It is believed to have invaded Western Europe via the Danube. It has spread across most of Western Europe over the last 10 years. It can grow to 30mm long in ideal conditions, much larger than our native freshwater shrimp. Specimens being recovered from and observed in Grafham Water at present are between 10 and 15mm in size. It often has striped or spotted markings. Due to its voracious appetite, it is commonly known as ‘killer shrimp’.

Why is it a problem? The killer shrimp is a voracious predator. It kills a range of native species, such as freshwater invertebrates, particularly native shrimps and even young fish. This alters the ecology of the habitats it invades. It often kills its prey and leaves it uneaten. It tends to dominate the habitats it invades, sometimes causing the extinction of native species.

Can it hurt people? It can bite you if you hold it, but this is no different to an insect bite, and it does not pose a risk to human health. There are no known health risks from drinking water from a reservoir that contains this shrimp. Water from Grafham is treated before it is supplied to homes in the region.

Is it found in the UK?
It has been found at Grafham Water, Cambridgeshire on 3rd September. This is a water supply reservoir popular for angling and watersports. Anglian Water and Environment Agency scientists are monitoring lakes and streams nearby to assess whether it has spread to other sites.

How did it get into the lake? We don’t know. The shrimp is now widespread on the continent, and any boat, trailer or kayak that had not been sufficiently cleaned after use on mainland Europe may have introduced it. It is possible that it may have been transferred by a migrating bird.

How long will it take to become established? It is already widespread and abundant within Grafham Water. The speed at which it will spread from Grafham will be determined by how far it has already spread. and how effective the biosecurity measures are at containing it. We are urgently monitoring the Diddington Brook, into which Grafham Water Flows and the Great Ouse, as well as surrounding lakes.

Is it safe to continue to use Grafham Water for watersports and angling? Yes, but all reservoir users must be very careful to avoid spreading the shrimp to other areas. Anglian Water and the Environment Agency are asking water users to ensure boats and trailers are thoroughly cleaned, particularly bilge areas, trailer wheels or box-sections of trailers. Anglers need to inspect and clean their equipment, particularly nets, removing and destroying any shrimps that are found.

Is it safe to eat fish from Grafham Water? There are no known health risks associated with eating fish that may have been feeding on this species of shrimp.

What is being done? Anglian Water is working closely with the Environment Agency and Defra to contain this problem. We are following a rapid response process developed under the GB Framework Strategy on Invasive Non-native Species.  Our immediate priority is to establish how widespread this species of shrimp is, and avoid any further spread.

’s the Environment Agency doing about it? We are helping to coordinate the effort to contain the shrimp. Our staff are monitoring lakes and streams nearby to establish whether it had spread. We are also alerting our staff across the country to look out for it during their sampling. We are working closely with Anglian Water to identify and assist with the implementation of appropriate biosecurity measures to limit any further spread of this species, providing technical assistance as required. Anglian Water is cooperating fully with this.

Will the killer shrimp be removed from Grafham Water? It is too early to state what action can be taken until the full extent of the spread has been determined. There are no known control methods currently available.

Why is the lake still open to the public? Because there is no risk to public health, and recreational users of the lake, assuming they take the appropriate biosecurity measures, should not cause further spread of the shrimp. There is absolutely no risk from land-based access to the reservoir. Anglian Water consider that it is safe to continue using Grafham Water for leisure activities if the appropriate biosecurity measures are followed.

What should sailors, kayakers and anglers do? All equipment must be inspected and thoroughly cleaned after use. Boat users must be particularly careful to ensure that trailers are completely cleaned after use. Boats and kayaks must be thoroughly cleaned and inspected. Anglers should ensure that nets and other equipment are disinfected.

What should the public do? This shrimp is one of many invasive non-native animals and plants that we spread by our activities. Please ensure that you clean boats and watersports equipment after use. Don’t move plants and animals around the countryside.

What should a member of the public do if they come across what they believe to be a non-native shrimp? Members of the public should carefully check the identification of the shrimp with details provided on Images of suspected non-native shrimps can be sent to for confirmation.

Threat of Killer shrimp highlighted prior to invasion

Pink peril threatens native species in Britain's rivers - Guardian 3 January 2001 Predatory impact of the freshwater invader Dikerogammerus villosus - Queen's University Belfast & University of Amsterdam–PDF-File, 4.2 MB