The hazel dormouse was once a common sight across much of the UK; however, loss and fragmentation of suitable habitat have contributed to a significant decline in populations. As such the hazel dormouse is afforded both UK and European protection which makes it an offence to: deliberately disturb, capture, injure or kill them; damage or destroy their breeding or resting places; disturb or obstruct access to any place used by them for shelter; possess, or sell a wild dormouse.

The hazel dormouse has a restricted UK population. They occur mainly in the southern counties especially: Devon, Somerset, Sussex and Kent, but are also patchily distributed across much of Wales, Cheshire, the Midlands and Yorkshire. Although hazel dormice are usually associated with broadleaved woodlands they occur in a wide variety of habitats including rural gardens, dense rhododendron, and reed beds. Therefore surveys should not be restricted to optimal habitat and instead should be undertaken in any woody habitat within their known range, which is likely to be affected by works.

Hazel dormice can be affected by various activities including: woodland and hedgerow management, the removal of hedgerows, woodland clearance, noise and lighting. In the majority of cases sensitive management can help prevent harm to dormice or their habitats, however, if this cannot be avoided a mitigation licence from Natural England will be required. EMEC Ecology can carry out hazel dormouse surveys, mitigation and licensing.


Hazel dormouse surveys should be carried out during the active season, usually April to November, dependent on the area of the UK. After this period the dormice enter hibernation. Nut searches can be carried out at any time of the year however they are best undertaken between September and December as the distinctive gnaw-marks can deteriorate over time. This method is restricted to habitats with hazel. Preliminary habitat assessments can be undertaken throughout the year, but are more beneficial if undertaken in conjunction with nut searches between September and December.


Prior to undertaking a hazel dormouse survey a preliminary habitat assessment will be undertaken and historical records consulted to determine the potential for dormice to be present.

A combination of the following methods may then be utilised in order to survey for the presence of hazel dormice:

  • Nut searches
  • Searching for wild nests
  • Nest-tube and nest-box surveys

To request a more detailed dormouse survey information sheet, please email

Following the Survey


We will provide a report detailing the survey methodology and results as well as providing an evaluation of the species recorded and recommendations for general mitigation measures, further surveys and / or consultation, as appropriate. The report will be provided as soon as possible following the survey, however; should you have a specific date for submission of a planning application we will do our utmost to accommodate this.

Dormouse Mitigation

Dependent upon the development proposals and the survey results, a variety of mitigation solutions may be proposed by EMEC Ecology. Some mitigation strategies must be undertaken under a European Protected Species (EPS) licence, which EMEC Ecology can arrange on behalf of the client.