Dormice Surveys & Mitigation

The hazel dormouse (as opposed to the much larger, and non-native, edible dormouse) measures around 14cm in length from head to tail. It is at its heaviest just before hibernation, weighing between 25-40g. The dormouse is distinguished from other rodents by its rounded, compact muzzle, orange-brown coat and thick bushy tail. The underparts are much paler, sometimes pure white. The most striking features of the dormouse’s head are the fine, black whiskers - these can be as long as 25-30mm long - and its large, prominent black eyes.

Dormice live in a variety of habitats, but are most associated with well-structured broadleaved woodlands and species-rich thick hedgerows. Sightings are rare: dormice are asleep for much of the year, active only between April and October/November (depending on the weather conditions). Signs of dormouse activity, such as nibbled hazelnuts or their nests, can give their presence away. Dormouse nests can be up to 150mm wide, are spherical and are usually woven from stripped bark and honeysuckle. They may be found in scrub and trees, in hedgerows and tree holes during the summer months. The smaller winter hibernation nests are built at or slightly below ground level at the base of trees, under leaf litter, wood-piles or rocks, where the dormouse can find constant temperature and moisture levels as it hibernates.

The Law

Dormice are fully-protected against killing, capture, injury and disturbance, and their habitats are protected against damage, destruction or obstruction, under the Conservation of Habitats and Species Regulations 2010 (as amended) and the Wildlife and Countryside Act 1981 (as amended). If dormice or evidence of dormouse presence are found on site after works have started, works in the area must stop immediately to avoid the law being broken. All potential dormouse habitat must be surveyed for dormouse activity. Dormice may only be handled by experienced ecologists who have the appropriate licence from Natural England.

Breaking the law can lead to fines of up to £5,000 per offence and potential prison sentences of up to six months. Vehicles implicated in an offence may be impounded and both the company and/or the individual(s) concerned can be held liable.

Expert Dormouse Consultants

Our ecologists can advise on and carry out all aspects of dormouse conservation and protection, from thorough and licensed field surveys to mitigation work, applications for European Protected Species Mitigation licencing and habitat enhancement. Our ecologists have worked on a range of rural and urban development projects.

Dormouse Surveys and Mitigation

The common or hazel dormouse may spend up to five months of the year asleep, hibernating when food is scarce, to conserve energy. Dormice can be found in suitable habitats throughout much of England (as far north as Cumbria and Northumberland) and Wales. The south of England is a particular stronghold for the hazel dormouse.

Surveys for dormice using nest tubes take place between March and October and nut searches are best undertaken from September to November.

Our experienced and licensed ecologists undertake:

• habitat assessment as an aid to determining likely presence and to target further surveys
• dormouse surveys using a range of methodologies as required
• applications for European Protected Species Mitigation licences for hazel dormouse
• translocation and mitigation for hazel dormouse

From specific projects, over a small area, to more comprehensive surveys for scientific studies in extensive habitats, The Ecology Consultancy has the experience and expertise to help ensure your dormouse surveys are completed efficiently.