Animal Facts Edible Dormouse

Cute and cuddly as it may appear, the edible dormouse is listed among the top dozen or so of mammals posing the greatest threat to Britain’s countryside. Its scientific name is Glis glis (also cited as Myoxus glis) and it is the largest of the dormice family.

It gets its common name from the days of the ancient Romans who considered the flesh of the creature a delicacy. It may also be called the ‘fat dormouse’ from its trait of feeding itself up before hibernation. They were sometimes ‘farmed’ by the Romans, in cages or kept in terracotta jars (glisaries) and fed acorns and chestnuts till they were nice and fat at which point they would be killed and eaten.

The natural range of the animal is across central Europe and Asia. They were introduced into a private zoo in Tring, Hertfordshire, England in 1902. Lord Lionel Walter Rothschild added some edible dormice to his collection but soon after they escaped and have since spread slowly but steadily through the Chiltern hills and beyond.

This species inhabits a variety of forests, orchards and urban edges. Mature deciduous woodlands, dense forests with rocky cliffs and caves all provide shelter and protection for these little animals.

The edible dormouse measures from 12 to 20cm in length with the tail adding another 11 to 19cm. It has a weight of 50 to 250 grams, reaching the higher weights just before hibernation. The pelage is a grey/brown on the upper surfaces with a clear line marking the change to the creamy-white colour on the belly. The fur is short and thick and the tail is very bushy. It is sometimes mistaken for a squirrel with its small ears, short legs and large paws. There are dark stripes on the outside of the legs and faint darker rings around the eyes. As an adaptation for climbing, the paws have hard pads. There are scent glands on the feet and at the base of the tail.

Dormice are nocturnal and spend their days in nests. It builds separate nests for summer and winter. They stick to a home range of about 100m diameter. Related individuals will often hibernate as a group. Hibernation may take place in old rabbit warrens, fox-holes, cavities in trees or in the rooves of buildings. They are good climbers and spend most of their time in the treetops.

The dormouse is mainly herbivorous but also adaptable. It feeds on bark, fruit, nuts, fungi, insects, carrion and eggs. It has also been known to take small birds. Before hibernation it may eat enough to almost double its weight.

The breeding season is between June and October. The female lays an odour trail by dragging her anal area along the ground when she is ready to mate. Once mating has occurred the male will leave to find another female. Males will fight each other during the mating season. A typical litter will number from 4 to 6 babies although up to nine may be born. The babies become independent in about a month. A nest is made, often in a hollow tree, and lined with soft material such as grass and feathers. The young are born blind and naked. Hibernation occurs from October to April, depending on the local climate. The animals hibernate in grass-lined hollows either underground or in trees. They may live up to twelve years in the wild which is unusually long for mammals of this size.

Deforestation has caused a decline in the population of the dormouse in parts of Europe. Predators include foxes, badgers, owls and birds of prey. However in England they are fast becoming a significant threat to the native wildlife. If present in large numbers, they cause damage in orchards by stripping the back and eating the fruit. They also chew through wires and wood in houses.

While considered a pest in Britain, the edible dormouse is declining in its native Europe and is regarded as ‘lower risk’ by the IUCN Red List.