Dormice

The common dormouse (Muscardinus avellanarius) was once widespread throughout many areas of England and Wales, but has since suffered a rapid decline and is now endangered.

Dormice are rarely seen due to the decline in their population, because they are largely nocturnal, and because they hibernate from October through to May. They are mostly found in woodland, hedgerows and dense scrub.

Their diet consists mainly of flowers, some insects, fruit and nuts, especially hazel which is the main food used to fatten up for hibernation.

Protection

Dormice and their habitats are now fully protected by the Habitats Regulations 2010 with some additional protection from the Wildlife and Countryside Act 1981. Dormice are a priority species in the UK Biodiversity Action Plan. Licensing procedures are administered by Natural England whenever development works are likely to disturb dormice habitat.

Planning permission can be refused on sites where dormice are found unless:

They will be adequately protected during the development works.
Disturbance to the dormice is kept to a minimum.
Alternative habitat can be provided.

Mitigation

Where land which is used as habitat by dormice is to be developed, the dormice must first be removed. If the dormouse population is small, and there is alternative suitable habitat adjoining the site, it is possible to clear the trees and vegetation to make the area unsuitable for dormice, therefore encouraging the dormice to leave the site of their own accord. However, this can only be done at certain times of the year, such as when the dormice are hibernating, or when they are active but have no dependant young. Please check our mitigation calendar for further details.

If the dormouse population is large, and if there is no suitable alternative habitat adjoining the site, then capturing, removing and providing new habitat for the dormice is the likely option. However, trapping and translocating is restricted to just 6 weeks of the year, which is when the dormice are not hibernating and when they are without dependant young.

Habitat Creation

Once new habitat for dormice has been created, it can be several years before it is established enough to be suitable for habitation. It is likely that a licence would be needed before creating or enhancing the habitat.

Habitat creation and enhancement for dormice could involve:

The creation of new woodland and planting of hedgerows.
Encouraging the growth of hazel in existing woodland by the thinning of tall trees of other species.
Installing dormouse nest boxes.
Connecting isolated areas of woodland together by planting woodland or hedgerows. This allows dormice to move across the landscape as they are reluctant to cross open spaces.
Introducing a programme of woodland management including the coppicing of hazel. Coppicing involves cutting the trees down to ground level which encourages fast re-growth and a prolonged life.

If you are undertaking development works which may impact dormouse habitat please call us on 01483 466066.