Hazel dormouse
Muscardinus avellanarius Linnaeus, 1758
Gliridae
| Other names | |
|---|---|
| Catalan | Rata dormidora rogenca |
| Spanish | Lirón enano |
| English | Hazel dormouse |
| French | Loir muscardin |
| German | Haselmaus |
| Features | |
|---|---|
| Weight | 17 - 30 g |
| Body measurements | 65-91 mm |
| Tail measurements | 57-86 mm |
Description
The hazel dormouse is the smallest of the five dormouse european species found in the Gliridae family. Like all dormice, it has large ears, protruding eyes and a long tail. The dorsal coat varies from grey to duller yellow to golden, depending on the age of the individual. It has a bushy tail and its colour matches the dorsal coat. On the belly, it has a duller yellow colour and a white spot on the throat, which runs down to the belly. It is an arboreal, nocturnal and hibernating animal. It is a fairly long-lived species (3 to 6 years) considering its small size.
It can be frequently found occupying nest boxes during its active period.
Distribution
The species is absent from Catalonia and the rest of the Iberian Peninsula. It is distributed throughout central and eastern Europe. Its range goes from central and eastern France to Russia, crossing the whole of Europe, reaching the north-east of Denmark and Sweden. It is also found in the British Isles (Wales and southern England). A population of the species has also been detected in Ireland. The southern limit of its distribution is Italy (including Sicily) and Turkey.
Habitat and feeding
Like the edible dormouse, the hazel dormouse is found predominantly in deciduous and mixed forests with well-developed undergrowth, but can also be found in scrub and coniferous forests. This species can live at altitudes of up to 2000 metres and is favoured by a diversity of tree and shrub species. A well-developed and connected undergrowth ensures security from predators and provides food.
It is a mainly vegetarian species that feeds on buds and flowers in spring, fleshy fruits in summer and seeds in autumn. In addition, in times of food shortage, especially in late spring or early summer, it may feed on insects and birds' eggs.
Breeding
Hazel dormouse sexual activity begins in June, a few weeks after awakening from dormancy, and ends in October shortly before hibernation begins again. Gestation lasts about 22-25 days. They may have up to 9 young per litter, although 3 to 7 young per female is the most common. This dormouse species builds nests with similar structure both in summer and winter. In general, nests can be classified into four different types, as suggested by Wachtendorf (1951): leaf nests (built with leaves from trees and shrubs), herbaceous nests (containing only grass or shredded bark), stratified nests (with an outer layer of leaves and an inner layer of grass or bark) and mixed nests (consisting of leaves and grass or bark, but disordered throughout the nest). The skill with which the nest is made and the presence of green leaves clearly differentiate a dormouse nest from the ones of other small mammals.
Status
According to the IUCN Red List, the hazel dormouse is considered to be of Least Concern and with an unknown global population trend. However, in much of its range it is declining and considered threatened, and it is also included on the red list in many countries, for example in England and Denmark. For this reason, the species has been included in Appendix III of the Bern Convention and also in Annex IV of the EU Habitats Directive, which obliges participating countries to protect the species and its habitats. Its main threats are deforestation, construction of urban areas and habitat fragmentation causing isolation of populations.
Acoustic comunication
Rodents of the family Gliridae (glyriids or dormice) vocalise; many species of this family are known to emit a wide variety of vocal signals and the hazel dormouse is one of them. However, relatively little is known about the function of these vocalisations. Some studies have investigated hazel dormouse communication and have shown that it can emit different vocalisations ranging from audible sounds to ultrasounds. The most complete and recent study describing the vocalisations of this species was carried out in 2013 by Ancillotto and company (link in references).
Links
Hazel dormouse article – Woodland Trust
Hazel dormouse species sheet – Mammal Society
Atlas of the mammals of Great Britain and Northern Ireland
Mammals of the British Isles: Handbook, 4th edition