Llanelli Naturalists Newsletter - Winter 1991/1992
Niel Matthews
The dormouse Muscardinus avellanarius is a very attractive small animal, covered with dense. soft fur which, above, is a golden-sandy colour; it is up to 8 cm long. not including the bushy tail which reaches up to a further 7 cm. It prefers woodland. wood edge or thick hedgerows where there is plenty of dense scrub, which provides both a source of food (eg hazel nuts) or shelter from predators eg bramble, gorse or hawthorn thickets. A wide variety of vegetable matter (bark of young shoots, nutritious pollen from hazel catkins or a range of wild fruit) is eaten; they may even open the spurs of honeysuckle flowers to reach the sweet nectar. The dormouse also, at times, eats insects.
They are agile climbers, finding a very high percentage of their sustenance by this method. Dormice make a loosely-constructed ball-shaped nest, out of grass, lengths of honeysuckle and leaves, off the ground (regularly about a metre or so) and often in the protective confines of a bramble brake. There are two breeding periods - May-June, and August-September, and three of four young are born (after a gestation period of 22-24 days); these youngsters remaining in the nest for about a month or so.
This nationally very-local mammal can be difficult to find, let alone observe. There are few records from Carmarthenshire, Barker (1906) for example, states that it "appears to be rather local in the County" and that he had "found a colony of these pretty little animals two or three years ago in one of our fields at Oaklands" ("Oaklands" - Barker's former home - still stands at the junction (SN425165) of the A484 from Kidwelly and the 64309 from Pontantwn. John Brunker, in his manuscript list (c.1950) of the mammals of Llanegwad Parish (SN52) - held in the Carmarthenshire Record Office (Dyfed County Council Archives ref. CDX/259/11) - stated that "the dormouse is rare, only one record of it's presence being noted." I am aware of a few (post-1970) definite records - from coastal blackthorn scrub etc on the coast at St. Ishmaels (SN363083) and another found in a nest-box in woodland around the Upper Lliedi Reservoir (SN50-04-); it is also reported from the Capel Dewi area (SN47-20-) in the lower Tywi valley and from Tir Philip SN48-18-. Additionally, this autumn (1991, per Mr & Mrs Crowden) one was unfortunately killed by a cat near Llwyn-teg, Llannon (at SN551079); subsequent searching of the tall hedgerows thereabouts has revealed the presence of the distinctive sharply-chiselled empty nut-shells left by feeding dormice (it's fondness of hazel-nuts has given it the alternative name "hazel-dormouse") Murrell (1981) writes that, "close examination of the hole made in a discarded nutshell will show a smoothly finished edge - the effect of the dormouse's very precise carpentry. This style of nut-opening is characteristic of the species and their discarded nutshells provide a most useful indication of their presence. The tooth marks made by both bank voles and wood mice around the edge of the hole are quite different. The leave a ribbed effect, rough to feel, like the rim of a 10p coin."
The dormouse hibernates from October to April, when it is vulnerable to predators, as this hibernation nest is built on the ground, in leaf litter, or in an old tree stump. It winters alone, it's fattened body humped up into almost a ball-shape in order to conserve heat. In the past when hedgerows were more carefully and manually trimmed and laid, the finding of a dormouse nest (with it's sleeping incumbent) would be a more regular event and there is evidence that in those days (when the dormouse was also more common), this species was more familiar to country people. In Wales, this is suggested by the proverb, "Cyn dewed a pathew" ("as fat as a dormouse").
It is believed that the dormouse has declined due to a variety of factors - the general ecological simplification that has affected the countryside - removal (or over-zealous trimming) of hedgerows and scrub, coniferization of broad-leaved woodland, or a cessation of traditional management (eg rotational coppicing). All these result in less of the dormouse's favoured habitat - deciduous woodland with a vigorous, unshaded and diverse understorey. However, it must be remembered that the dormouse is easily overlooked and that no records during a survey are not necessarily an indication of actual absence. The. best time to observe dormice is said to be in the late evening, before the light has completely disappeared, with observations being made against a light source (eg sunset) so that the dormouse is silhouetted: it is perhaps far more productive to search for other evidence - the nests or empty nut-shells. The dormouse should, for example, persist in the still thickly-hedgerowed Landscape of Coalfield Carmarthenshire or at other apparently ideal sites such as Carmel Woods with its frequency of scrub and abundant hazel). It may be that this species is widely - if thinly - spread throughout much of the county. Records will always be welcomed by the author. (Neil Mathew, "Towy View", Bethlehem Road, Ffairfach, Llandeilo, Dyfed, SA19 6TG, Tel: Llandeilo (0558) 822349).
References
Anon (1984) Field Guide to the Animals of Britain. Reader's Digest Nature Lover's Library. (A relatively cheap text, accurate and well-illustrated - available at W.H. Smith. ISBN 0-276-36006-0).
Barker, T.W. (1906) A Handbook to the Natural History of Carmarthenshire. W. Spurrel & Son, Carmarthen.
Bright, P & Morris, P (1989) A practical guide to dormouse conservation. The Mammal Society. Occasional Publication Noll
