Extensive research has shown that the native white-clawed crayfish is thriving in Cumbria, which is now its most important stronghold in the UK. The county has the most rivers which contain this crayfish but remain free of its deadly American cousin and they disease they carry.
The native crayfish is being wiped out across the UK. The introduced American signal crayfish is larger, more aggressive and prolific, and it also carries a disease called crayfish plague. Once in a river, the invader and its disease can quickly eradicate the smaller British counterpart. They also cause significant damage to river banks and other river wildlife.
Crayfish surveys have been carried out in the Eden Valley over the last four years by Eden Rivers Trust, assisted by an army of excellent volunteers. They have found native crayfish in the River Eden and many of its tributaries, including the Rivers Lowther, Eamont, Leith and Lyvennet near Penrith. White-clawed crayfish are also abundant in the Hoff and Helm Becks near Appleby, the Scandal Beck near Kirkby Stephen, the Hayber Beck near Warcop, and the Croglin Beck near Croglin. No non-native crayfish or crayfish plague have so far been recorded in the Eden Valley and it is hoped to keep it that way.
Eden Rivers Trust is keen to hear from anyone with information about crayfish in other Pennine becks. These areas are difficult to survey because the becks are small and numerous, so any reports from landowners or the general public on the presence of crayfish in the Pennine streams would be very welcome.
Crayfish surveys will continue this summer and if anyone is interesting in joining in and having a go at crayfish surveying, they can contact Eden Rivers Trust on Tel. 01768 866788 or email office@edenriverstrust.org.uk. There is a Crayfish Survey Training Day on 4 August and a few places are still available for this fascinating insight into a local rarity.
Joanne Backshall, Conservation Officer at Eden Rivers Trust, said, “While the healthy state of Eden’s crayfish population is fantastic news it is important not to be complacent. The threat from signal crayfish and crayfish plague is ever present. We are urging all river users to be vigilant when moving between different waterways, to “Check, Clean and Dry” clothes and equipment, so that unwanted crayfish and disease are not inadvertently carried with them.”
To keep native crayfish thriving in the Eden Valley, Eden Rivers Trust has been carrying out improvements along the rivers. During last winter over 3000 broadleaved native trees have been planted and more than 1000 m of riverside fencing completed. This will enhance conditions for crayfish and other wildlife such as king fishers, otters and red squirrels. Improvements around farms, such as concreting farm yards and changing drainage systems, have also been undertaken to reduce sediment and pollution in the river.
This work has been funded by SITA Trust, Natural England, the Forestry Commission and The Woodland Trust. The Trust is currently preparing a major funding bid for a partnership project to continue this important conservation work.
If you would like to learn more about the work of Eden Rivers Trust, you can visit www.edenriverstrust.org.uk. Alternatively, email office@edenriverstrust.org.uk or telephone the office, which is at Skirsgill Business Park, Penrith, on tel. no. 01768 866788.
