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posted 2 Oct 2010, 09:52 by Haley Whittall   [ updated 2 Oct 2010, 11:12 ]
The Common (or Hazel) Dormouse (Muscardinus avellanarius) is about three inches long (7.5cm ) with a two inch (6.5cm) long furry tail.  Dormice can be distinguished from other mice by their ginger coloured coat , thick bushy tail and large, prominent black eyes.

Dormice are nocturnal and arboreal so are seldom seen.

Dormouse means “sleeping mouse”.  They can spend nearly half the year (October to May or sometimes November to April – depending on the weather) in a winter ‘sleep’, when their body temperature , heart rate and breathing rate drop.  Even in summer, part of the day can be spent in a torpid state.  It is a way of reducing energy needs at times when food is hard to find.  They tend to hibernate at ground level in tree stumps or log piles, at the base of coppice stools or among dense leaf litter and occasionally in compost heaps:
Dormouse emerging from a compost heap in a Crowborough garden
Dormice eat fruits, berries, seeds and nuts, pollen and nectar from flowers as well as insects such as aphids and caterpillars when other food is scarce.  Many of the things that Dormice feed on are only available for a short period each year so they need habitats with a good variety of food sources.

The natural life span of a dormouse in the wild is unknown. However it is believed that they usually live for about three years.

Traditionally Dormice were thought to occur only in large areas of coppiced woodland and ecological surveys by the majority of professional ecologists only targeted this type of habitat.  In recent years Dormice have been recorded in ‘untypical’ habitats including coniferous woodland, overgrown gardens, areas of scrub and most surprisingly, in a bamboo plantation near Hailsham and young birch woodland on Ashdown Forest.  Hedgerows are a prime habitat for Dormice, particularly where they link with areas of woodland or scrub.  In a recent survey undertaken for a new water supply pipeline, Dormice where found in numerous roadside hedgerows between Jarvis Brook and Rotherfield.

A good indication of the presence of Dormice is characteristically gnawed Hazelnut shells.  The way a Dormouse opens a Hazel nut is different from other small mammals.  Nuts opened by Woodmice and Bank voles have a corrugated edge around the inside of the hole.  Dormice make a neat round hole in the nut but with a smooth inside edge made by the lower incisors as the nut was rotated.  The outside edge has small scratch marks made by the upper incisors as they grip the shell.

More detailed Dormouse surveys involve the placement and monitoring of specially designed dormice tubes, or nesting boxes, as currently being undertaken by Kate Ryland of Dolphin Ecological Surveys at the Ghyll and Country Park.  These specialist surveys can only be undertaken by a suitably qualified and licensed ecologist.

Dormice are protected under UK legislation by the Wildlife and Countryside Act 1981 and also under European legislation by the Conservation of Habitats & Species Regulations 2110.

It is an offence to intentionally or recklessly kill, injure, take, possess, sell or disturb Dormice as well as to intentionally or recklessly damage, destroy or obstruct their place of shelter or protection.

It is estimated that Dormice in Britain have suffered a 70% population reduction in the last 25 years.  Some estimates suggest that there are now only 40,000 Dormice left in the UK, mostly in the South West of England and South Wales.
By Barry Kemp