New invasive crayfish even more damaging

Environment Agency tracks alien invaders
January 2012. The Environment Agency is using radio transmitters to locate and track a ferocious predator invading English waterways. The virile crayfish, a highly aggressive non-native crayfish, is slowly invading waterways in East London. This unwanted visitor preys on native wildlife and spreads crayfish plague, a disease deadly to native white clawed crayfish.

First found in 2004
The Environment Agency is tracking the progress of virile crayfish by installing small radio-transmitters on the backs of these environmental trouble-makers. Originally from North America, their spread is unabated by cold weather. They were first found on the River Lee near Enfield in 2004 and have since colonised over 17 kilometres of the river and connected waterways, spreading into Hertfordshire. 


Preliminary results show that virile crayfish are moving upstream at a rate of 500 metres per month, substantially faster than their non-native cousin, the signal crayfish.

White clawed crayfish
The UK's only native crayfish, the white clawed crayfish, was wiped out along the River Lee following the invasion of the signal crayfish in the 1980s and the associated spread of crayfish plague. The Environment Agency's work on the River Lee in Cheshunt will give a better understanding of the movement and lifecycle of the signal and virile crayfish. By better understanding the spread of virile crayfish, this work will contribute to efforts to safeguard native white clawed crayfish elsewhere in the country. 

Adam Ellis, Environmental Monitoring Officer at the Environment Agency said: "Whilst rivers in England and Wales are cleaner than they have been for decades, there is still a lot to be done in order to return them to full health. This includes the control of invasive species like virile crayfish.


Read more:  http://www.wildlifeextra.com/go/news/virile-crayfish.html