Roach's Mouse-tailed Dormouse | Myomimus roachi

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Tracks

Hardly any signs have been described, because the species is rarely found. Most knowledge of the species comes from Barn Owl pellets; collecting pellets under church towers or barns in south-eastern Bulgaria or Turkish Thrace and examining the skulls is therefore the first step. On the living animal two features are usable. First the tree cavity: the species rests by day in cavities of old trees along streams, in hedges or in orchards, and disappears where such trees disappear; rows of pollard willows or old walnut and mulberry trees with cavities are the most suitable landscape features. Second the winter burrow: this species digs its own burrow about twelve centimetres deep in the ground for hibernation, where it remains from mid-November to late April; the Edible Dormouse too usually hibernates in the soil, in a burrow it digs or finds. The droppings are small, dark and cylindrical, like those of a Wood Mouse, and cannot be assigned with certainty without the animal. For this species the owl pellet is the main source; other signs are supplementary.

Identification

A dormouse with the appearance of a mouse. Head-body 8.5 to 13.5 cm, tail 6.5 to 9.5 cm; the tail is therefore shorter than the body, whereas all other European dormice have a tail as long as or longer than the body. The tail is also short-haired and sparsely furred, without a brush, tassel or white tip; only at the tip is the hair slightly longer. The back is grey-brown to sandy grey, sharply separated from the white to off-white throat, chest and belly. There is no mask and no eye stripe; the face is plain, which distinguishes the species from the Garden, Forest and Asian Garden Dormice. The ears are small to medium (13 to 18 mm) and rounded, the eyes large and black, the hind foot 19 to 23 mm. Weight is 21 to 70 g and varies strongly with season.

Similar species

The main source of confusion is a true mouse. In an unclear photograph or in torchlight the species resembles a Wood Mouse or Yellow-necked Mouse, which occur in the same landscape. The difference lies in tail and head: the Wood Mouse has a naked, clearly ringed tail as long as or longer than the body, very large ears and a pointed muzzle, and moves by bounding; the Mouse-tailed Dormouse has a shorter, sparsely haired tail without rings, a shorter and blunter muzzle, and climbs rather than leaps. The Forest Dormouse occurs alongside it in Bulgaria and has a black eye stripe and a bushy tail. The Hazel Dormouse is golden orange with a densely furred tail. With an animal in the hand the combination of a dormouse foot, a plain face and a short, mouse-like tail is decisive; in the field this often cannot be established, and the record is then entered as 'undetermined'.

Habitat

Lowland, in the transition zone between woodland and open arable: riparian woodland and scrub along streams and rivers, old hedges between fields, vineyards, mulberry and almond orchards and overgrown field margins. Old trees with cavities in this half-open landscape are required. Closed forest is not inhabited, and the species disappears from large-scale, intensively worked arable land without woody margins. It is thus bound to the traditional small-scale farmland of the northern Aegean region, a landscape type that is itself declining in extent.

Distribution

A strongly fragmented range in the north-eastern Mediterranean: south-eastern Bulgaria (the Thracian lowland and the Strandzha) and Turkish Thrace and the Aegean coast of western Anatolia, with the present centre in a few small woods near Edirne. Occurrence in north-eastern Greece was long suspected and has recently been confirmed. Outside this area the species does not occur. Fossil material (the species was described from late Pleistocene layers in Tabun Cave on Mount Carmel in Israel) shows that it formerly inhabited a much larger part of the eastern Mediterranean; the present populations are a relict at the north-western edge of that former range.

• Native
• dark = core range, pale = thinly spread

Way of life

Nocturnal and crepuscular, with two peaks: from sunset to around midnight and around and after sunrise. The species moves both in trees and on the ground, which is unusual among dormice; it is less tied to the canopy than the Hazel Dormouse and less to rock than the Garden Dormouse. The diet is predominantly animal, with a preference for insects, especially grasshoppers and moths, supplemented with fruit, seeds and nuts. The species is active from April to November and hibernates from mid-November to late April in a self-dug burrow. Breeding takes place in late April and early May, with five to six young per litter; young females also breed. Little else is known of its way of life.

Where and when to look

The chance of seeing the species is small. The most reliable method of recording it is the examination of owl pellets: collect material under a Barn Owl roost in south-eastern Bulgaria or Turkish Thrace and have the skulls identified. For a sighting of the animal itself, old hedges or strips of riparian woodland along streams in the Bulgarian Thracian plain are most suitable, in May or June, in the first hour after sunset, searching the trunks of old, hollow trees with a weak lamp. Every observation is of value and should be reported; in some regions the number of modern records can be counted on one hand.

Conservation status

Vulnerable (2022). The range is small, strongly fragmented and declining. The main cause is agricultural intensification: the removal of hedges and field margins, the grubbing out of old orchards and above all the felling of old, hollow trees used as daytime refuges. The species is nowhere common, so each local population is small and can disappear quickly. Conservation measures consist of retaining old trees with cavities, hedges between fields and scrub along streams.

Scientific name

Myomimus roachi | (Bate, 1937)

Bate described the species in 1937 as Philistomys roachi; because it was later moved to another genus, the author and year stand in brackets. Myomimus is Greek, from mys, genitive myos, 'mouse', and mimos, 'mimic': the dormouse that passes for a mouse. roachi honours a Roach. Bate described the animal as a fossil from the caves of Mount Carmel and gives no explanation, so who she meant is not established. The specimen the first description was based on came from Israel, Mount Carmel.