Several news sources are reporting that North American signal crayfish have been detected in the Eden River catchment in Cumbria, considered a UK stronghold of the native white-clawed crayfish. This is very bad news indeed.
Once signal crayfish have entered a catchment, the writing is on the wall, and it is only a matter of time before they come into contact with white-clawed crayfish, and the plague takes its toll. Unless, that is, serious and coordinated conservation efforts can be put into action.
The news has been broken by several sources in Cumbria, including a local newspaper and the Eden Rivers Trust (http://trust.edenriverstrust.org.uk/white-clawed-crayfish-page-3.html). They report that signal crayfish have been found in a tributary of the River Eden, and have probably been there for many years.