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GreyDormouse (Glis Glis)

In appearance, the Glis Glis is like a small version of the Grey Squirrel. The head and body are about 150mm (6") and the bushy tail is about 125mm(5"). The fur is silvery grey, shading to a light colour underneath, and there is a ring of black hair round 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 bringing what is, in effect, a pest. Glis Glis 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.

The alternative 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, Glis Glis 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.

Glis Glis 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 Glis emerge from hibernation in May, and that a litter of 2 - 5 young is 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 Glis in captivity surviving for 8 years.

The 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 Glis Glis are regarded as vermin, it is perfectly legal for householders to get rid of them. There are very strict laws about how this can be done, and each Pest Technician has work under a Government license.

Please note however that if you ask us to treat an infestation, we have to kill the animals we catch - it is illegal for us 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. All this does is give your pest problem to someone else.