Biosecurity in response to the invasive shrimp, Dikerogammarus villosus

Dr Mark Diamond, Environment Agency

Current situation

Grafham Water Diddington Brook ?Cardiff BayEglwys Nunydd & Tata’s ditch

Monitoring:80 other sites considered at risk are all negative

Kick-sampling and trap-sampling ongoing

Biosecurity at known locations

Local Risk Assessment and management plan produced for the three sites

Anglers

Water Sports

Diddington Brook / Tata ditch

Testing of efficacy of biosecurity measures at Grafham Water

Biosecurity : what have we learnt ?

Jet-washing greatly reduces the numbers of shrimpSmall shrimps are hard to see (!)

The residual risk from boatsand trailers is low after supervised biosecurity

Nets, bass bags and neoprene stocking and boot waders need particular attention

Disinfectant needed (R&D started)

Biosecurity what have we learnt 2: Survival in damp conditions

In a concrete outbuilding (1 – 10 oC)

Survived 6 days on a folded damp net

9 days in a plastic groove

15 days in a folded wader

All die within 48 hours of drying

Ideal biosecurity: current advice

Signage and guidance on-siteOne point of access, with supervisionAll equipment that enters site should be clean and have been dry for 48 hoursMinimise contact with waterAfter use equipment should be thoroughly washed and thoroughly dry for 48 hours before being used elsewhereIndependent post-biosecurity check

How can Riverfly Partnership and AMI help?

Look out for the shrimp when monitoring

Take biosecurity measureswhen sampling

Promote good biosecurity elsewhere

Further information at https://secure.fera.defra.gov.uk/nonnativespecies/alerts/index.cfm?id=3