Non-native animals cause rural problems, charity warns

http://news.bbc.co.uk/1/hi/uk/8602358.stm

A number of non-native mammal species are damaging the UK countryside by eating crops and threatening wildlife, a conservation charity has warned.
A report by the People's Trust for Endangered Species identified 14 problem species including rats, American mink and muntjac deer.
The trust said some of the creatures have been in the UK for so long, they are thought of as indigenous.
It said it was important to stop the extinction of native species.
Practical action
According to the report, two of the UK's fastest declining native species - the red squirrel and the water vole - which has declined by 90% - are under threat by mammals introduced by humans in the last two centuries.