Archive
NOT SO COMMON DORMOUSE
23/11/2023
I have always known Muscardinus avellanarius (Linnaeus, 1758) as the “common dormouse”. It became known as the “hazel dormouse” some years ago as its populations declined. Not to be confused with the introduced edible or fat dormouse, Glis glis (Linnaeus, 1766) — ask someone who studied the diet of ancient Romans — our hazel dormouse is a native species with a habitat range mainly of Wales and north to the Midlands in England with occasional outliers, although feeding signs and the typical nests of honeysuckle bark are easier to find than the animals themselves which are nocturnal as well as hibernating for six months of the year. It used to be relatively common in woodland understorey and along hedgerows where its favourite fattening-for-winter hazelnut food was more available before grey squirrels came on the scene and many woods were cleared of shrubby understorey or managed to grow without a shrub stratum, but has been declining severely for many years, despite regular reintroductions since 1993. Milder winters also mean they awaken from hibernation too often/too soon which depletes their energy that they cannot replenish.
The People’s Trust for Endangered Species issued a report[1] recently which found that populations have declined by 70% since 2000 and are extinct in twenty English counties. It would be an ecological tragedy for this little endemic and much-loved mammal to become another extinction in Britain.
Betts Ecology have sites that are favourable for hazel dormice and we have nest boxes for them but we have very few records. Do please keep a look-out for them or signs of them and let us know if you find any. There is a useful guide to field signs you can download from the Mammal Society here: https://bit.ly/dormousesigns. Please remember these mammals are strictly protected by law. If you do find signs of them, we can arrange a survey of the area by our qualified staff under appropriate licence.
