Muscardinus avellanarius

  1. Wildlife
  2. Mammals
  3. Dormouse


A small mammal, the Dormouse is also known as the Hazel Dormouse. Agile climbers and mainly nocturnal, dormice are very rarely seen. They live in deciduous woodland, hedgerows and dense scrub and can spend their entire lives up in the branches without ever touching the ground. The Dormouse eats buds, hazelnuts, berries and insects. It builds summer nests of stripped honeysuckle bark in which the female will give birth to up to seven young. They hibernate during the winter months, in a dense nest built in a tree cavity or similar, sheltered place.

How to identify

The Dormouse has gingery-brown fur, large black eyes and a fluffy tail; it is much smaller than a Squirrel.

Where to find it

Southern England and Wales.


When to find it

  • April
  • May
  • June
  • July
  • August
  • September
  • October

How can people help

Despite its name, the Dormouse is suffering from loss of habitat and suitable places to nest. Local Wildlife Trusts are helping this species by providing nestboxes, monitoring populations and even overseeing relocation and reintroduction programmes - the Berks, Bucks and Oxon Wildlife Trust, for example, took a Dormouse population from Kent which had been displaced by the Channel Tunnel, and relocated it to a woodland in Buckinghamshire. These animals are now doing really well. Support your local Wildlife Trust and the work they do by becoming a member.

Species information

Common name
Latin name
Muscardinus avellanarius
Length: 8cm plus a tail of 6cm Weight: 15-40g Average lifespan: 4 years
Conservation status
Classified as a Priority Species in the UK Biodiversity Action Plan.