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FACT SHEET - Glis Glis

In appearance, the glisglis is like a small version of the grey squirrel. The head and body are about 150mm (6") long and the bushy tail is about 125mm (5") long. The fur is silvery grey, shading to a light colour underneath and there is a ring of black hair around each eye.

The animal is common in Europe, but is not native to Britain. It was deliberately introduced into Tring Park in 1902 and has spread into the surrounding area. The extent of the spread is not fully known, but is thought to be no more than about a 30 mile circle from Tring, although there have been unconfirmed reports of sightings at much greater distances. Today, the introduction of new, wild, species is prohibited by environmental laws, but at that time no one had any concern for the long term implications of releasing what is, in effect, a pest into the UK. Glisglis cause considerable damage to trees and crops, and from the mid 1920's onwards were causing damage in houses, particularly by gnawing woodwork and electric cables.

Glis GlisThe common name "edible dormouse" dates from Roman times. The Romans farmed them by keeping them confined and fed a diet to encourage them to become fat. They were then served as an exotic delicacy at banquets.

Like many small animals, glisglis can appear to be attractive and entertaining. However, they are definitely not to be regarded as a pet or a cuddly toy. They have been described as sulky, standoffish and at times bad tempered. Once fully emerged from hibernation they are very nimble and fast on their feet.

Glisglis are nocturnal and in houses the first signs of infestation will either be noises heard in the loft at night, or signs of damage in the loft or outbuildings. The animals hibernate for long periods (the German common name for them is "Seven months" because they hibernate for the 7 months October - April)

Only limited research has been done on the life cycle of the UK population. It is thought that glisglis emerge from hibernation in May and that a litter of 2 - 5 young are produced in July - August. It is possible that there may be more than one litter each year, but precise information is lacking. By the standards of small rodents, glis glis have fairly long lives. It is known that animals in the wild live for 3 - 5 years and there is a record of a glisglis in captivity surviving for 8 years. They are rarely found outside the Luton, Beaconsfield and Aylesbury triangle, where they are fairly common.

Glis GlisThe small litter size and the small number of litters per year, together with action of natural predators mean that Glis glis do not multiply out of control the way that rats and mice do. However, they are slowly extending the infested area and this will be aided if there is a tendency to warmer spring and summer weather.

Because glisglis are regarded as pests, it is illegal for householders to release them back into the wild. There are very strict laws about how glissgliss must be caught and dispatched, everyone involved mustwork under strict Government license terms. Do not be tempted to control glisglis without recourse to a licence or a company working under such licence terms. Otherwise you may commit a criminal offence.

Please note that the terms of the licence is to kill the animals caught by specific means - it is illegal to remove them and release them alive in another area. It is thought that some of the spread of glis glis to other areas has been caused by well-meaning householders who have trapped glis glis and then, out of a mistaken sense of humane disposal have released them. Not only is this illegal but all this does is present the problem to someone else.

Natural England Advice - resolving problems involving edible dormice
Problems involving dormice may be resolved without recourse to a licence. For advice from the regulatory body on edible dormice contact Natural England on 0854 6003078, or at will either assist you directly or put you in touch with your local Wildlife Management Adviser. Advisers can offer guidance to you over the telephone to ensure you do not contravene any legal methods of control.

SDK (Environmental) Ltd trading as Dial A Pest, Acorn House, Aspen Way TQ4 7QR.
Full terms & conditions can be found at