Over the last 100 years dormice have become extinct across half their range in England. The continuing loss of ancient woodland, the splitting of big woods into smaller ones and unsympathetic woodland management have all contributed to this major decline.For example, dormice, being tree-dwellers, are reluctant to cross open ground, so if the wood in which they live becomes isolated and too small to provide sufficient habitat for the animals' needs they cannot survive and the species becomes locally extinct. Dormice have very special feeding requirements. They do not live in large numbers at any one site and are not able to easily move away to find new sites. They are very sensitive to changes in their habitat and the climate, so they are an excellent barometer of the health of our woodlands and hedgerows. A decline in dormice is a warning of danger to other species. Conversely, what is good for dormice is also good for many other animals too. We can use it as an indicator species to measure the success of landscape conservation measures.   Coppicing (cutting trees and woody shrubs to ground level every few years to provide wood for things like fencing materials) was once widespread, but has now almost disappeared. This traditional management created ideal habitat for dormice, with sprawling branches to provide pathways above the ground, plenty of different shrub species to provide food and not too much shade from big trees overhead.   Although there is now interest in bringing back this traditional management it is important to ensure that the cleared areas are not too large and that there is a long enough gap between coppicing operations (ideally 15 - 20 years) to allow the hazel trees to grow and produce nuts.