Our Dormouse project

A dormouse on the Stourhead estate in Wiltshire

In 2008, we secured funding for a survey of its 2,650 acre estate, to find out whether or not it was home to the endangered hazel dormouse (Muscardinus avellanarius). The project monitors and protects our resident dormice and their habitat.

The hazel dormouse, native to Britain, is honey coloured with a furry tail and large black eyes, making it easily distinguishable from other species of mouse.

They are nocturnal animals and, from April to November, they spend their time nesting in hedgerows and tree canopies, hardly coming to the ground at all. During the winter months dormice hibernate on or under the ground. Due to their elusive, nocturnal lifestyle they are rarely seen.

Dormice are vulnerable to woodland and hedgerow management operations and as a result of this, numbers are thought to have declined by half over the last 100 years. The hazel dormouse is now strictly protected by both UK law and European law, and you need a licence to be able to check nesting boxes and handle them.

Our project 

With the help of a team of volunteers, our ranger and licensed-handler Tamsin Holmes built 167 dormouse nest boxes and erected them in targeted woodland areas. Box checks first took place in May 2009 when four dormice were found.

Our most recent survey in November 2011 showed 33 out of our now 183 nest boxes are occupied, with sightings of dormice nesting in each of them – a fantastic result.

Will you spot a dormouse on your visit?
Dormouse being held in a hand
Will you spot a dormouse on your visit?

Tamsin and the team will continue to survey the estate for dormice, hopefully finding them in even more locations, as well as monitoring them in areas where they have already been found.

Due to the nature of the National Trust’s work, we are able to manage Stourhead's woodlands in such a way as to encourage dormice and, with a bit of luck, increase their population across the estate.

The Peoples’ Trust for Endangered Species

Stourhead is registered with the Peoples’ Trust for Endangered Species as a dormouse monitoring site. Results of our surveys are sent to them for the National Dormouse Monitoring Programme.