Dormouse nests – now is the time to search – December. – Wildlife and Ecology, the Wildlife Encyclopaedia

David Beeson, December 2022

WHEN? Finding the nests of dormice is difficult. However, December is the very best month as the leaves will have fallen from the shrubs in which they nest, and the flimsy nests will not yet have been destroyed by the winter weather.

WHERE? Here, in Northern Hampshire (UK) the dormice are most easily found in shrubby woodland, especially if hazel is frequent. In the past, I have searched in semi-open, coppiced woodland with poor results. However, now I have the perfect location.

The local landowner had a road margin layered about five years ago. This involves half-cutting shrub stems and bending them down. Stakes hold the living stems in place and they respond by sending up multiple vertical shoots that thicken the hedge. Dormice find the habitat ideal and I can walk the country lane and look into the hedge. I found 7 nests in about 200m of this layered coppice.

NEST DESIGN & LOCATION? Woodmice and yellow-necked mice usually wild nest underground, so one is unlikely to see these in a coppiced hedgerow. Voles nest at ground level. Shrew nests are similar but more difficult to locate. Harvest mice nests are mostly within a metre of the ground and flimsy in construction.

Above: two harvest mouse nests. Breeding and individual. Both low down.

Field or short-tailed vole nest. Short grass used, but not long stands or woven.

Decaying wren’s nest. Unwoven and included many leaves – but the same dimensions as a dormouse breeding nest.

Dormice generate two main nest types. Imagine your two fists together – that’s about the size of a breeding nest. Individual animals build smaller and less compact sleeping nests in summer – smaller than a single fist.

Construction is with fine bark or, more often, grassy-like materials. It is dome-shaped with no clear entrance – unlike a wren or long-tailed tit’s nest. Leaves are seldom incorporated into a dormouse nest but are common with wrens.

The dormouse nests that I have located (some could well be lower) are at head height to two or more metres into the shrubby vegetation. They are wound into a branching point.

By now, the dormice should be hibernating underground and the nests will be unoccupied. I last spotted my garden dormice this year at the start of November and last year in late November. (Of course, they could have been active elsewhere after those dates.) The single hibernating dormouse I have located was in a nest in open woodland just beneath the leaf litter layer. It was encountered during hazel coppice conservation.

GENERAL ADVICE. Select your search location carefully. Find continuous shrubs that are diverse in their species range and dense. Bramble is an advantage and should be viewed carefully as that is an ideal spot!