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Non natives

Threats to our freshwater environment by non-native species

CHECK CLEAN DRY - prevent the spread

An increasing number of non native species are threatening our river habitats and native species.  There is an urgent call for action regarding the threat of the Killer shrimp found for the first time in the UK in September 2010. The Riverfly Partnership endorses the work of partners, the Angling Trust (AT), Association of Rivers Trust (ART), River and Fisheries Trust Scotland (RAFTS) and Eden Rivers Trust amongst others in the development of catchment wide biosecurity measures and management practices to protect our freshwater environment. Alien Attack - Angling Trust / Environment Agency partnership project There is increasingly concern of the threats to our rivers, waterways and still waters from invasive non-native species. Estimates suggest that anglers are spending in the region of 100,000 man hours each year trying to tackle alien weeds and creatures to help protect our river habitats. The Angling Trust, with the assistance of the EA and the GB Non Native Species Secretariat,  brings together identification and managment information on 17 invasive non-native species threatening the aquatic environment. See here for full details. Stop the spread –PDF Poster, 251 KB

ALERT - call for action The Riverfly Partnership call Riverfly Monitoring Initiative Groups and partners to look out for the Demon and Killer shrimps whilst monitoring. If you find the Demon or Killer shrimp, send a photo and details of location, together with your contact details to Follow biosecurity measures to avoid the spread of these species.

Demon shrimp Dikerogammarus haemobaphes

A relative of the Killer shrimp, the Demon shrimp Dikerogammarus haemobaphes was first discovered in the UK, in the Midlands, reported on 4 October 2012.  Surveillance and risk assessments are ongoing. See FBA guide for ID.

Killer shrimp Dikerogammarus villosus

The Killer shrimp was first discovered in the UK in September 2012 in Grafham Water and has since been found in Cardiff Bay and the Norfolk Broads. For further information see here.  Size and colour are useful aids to identification, and the projections on the lower body are definitive features. Refer to the Freshwater Biological Association identification sheet.  Killer shrimp identification sheet (Freshwater Biological Association) –PDF-File, 601.24 KB Killer shrimp information (Non Native Species Secretariat) 


Signal Crayfish

Signal Crayfish factsheet –PDF-File

Giant Hogweed

Giant Hogweed factsheet –PDF-File

Himalayan Balsam

Himalayan Balsam factsheet –PDF-File

Japanese Knotweed

Japanese Knotweed factsheet –PDF-File