Graphiurus murinus

Geographic Range

Woodland dormice occur throughout Ethiopian region. They are widely distributed throughout Africa, from the southern edge of the Sahara Desert to Cape Province, South Africa.

• Biogeographic Regions
• ethiopian ethiopian
  • native native

Habitat

Woodland dormice are generalists and can be found in a broad range of habitats. Although they commonly nest in Acacia trees, their nests can also be found in tree hollows, rock crevices, on tree branches, in shrubs and even in abandoned bird nests and bee hives.

• Habitat Regions
• temperate temperate
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland
• forest forest

• Other Habitat Features
• agricultural agricultural

Physical Description

Woodland dormice are one of the larger African dormice species, ranging from 70 to 165 mm in head and body length and from 50 to 135 mm in tail length. They are squirrel-like in appearance, with dorsal pelage that ranges from light to dark gray and ventral pelage that is buffy white. They have short, soft wooly hair and a long bushy tail. A ring of darker fur often encircles their black eyes, and their ears range in length (a commonly used metric for species identification in mice) from 10 to 20 mm. They have short curved claws and their hind feet range in length from 15 to 20 mm. Woodland dormice range in mass from 23 to 34 g and are often confused with savannah dormice, which are detectably smaller. Their braincase is moderately cuboidal and domed, with slightly enlarged auditory bullae.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

Reproduction

Limited information is available on the mating system of woodland dormice. At the onset of breeding season, however, males are very territorial and aggressive towards one another, suggesting polygyny. Once they emerge from their hibernacula, many species of dormice call out to alert potential mates of their presence. Once mated, males are likely to leave prior mates to search for additional estrous females.

• Mating System
• polygynous polygynous

Although most breeding occurs during the summer (October through February), woodland dormice commonly breed throughout the year (i.e., seasonal polyestry). Females have 1 to 2 litters per year. Gestation is thought to last for approximately 24 days, resulting in 3 to 4 altricial pups per litter; however, as many as 6 pups per litter may be possible. Pups weigh approximately 3.5 g at birth, and they are not reproductively mature until the summer after their first hibernation.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
• viviparous viviparous

Little information is available on the parental investments of woodland dormice. However, newborns are altricial and independence from the mother most likely occurs between 4 and 6 weeks of age. Mothers provide protection, grooming, and nourishment (e.g., nursing) until pups reach independence. Pups are cared for in nests lined with moss, which are often found in tree hollows, rock crevices, on tree branches, in shrubs and even in abandoned bird nests and bee hives. Detailed information on paternal investment has not been reported.

• Parental Investment
• altricial altricial
• female parental care female parental care
• pre-fertilization
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female
• pre-independence
  • provisioning
    • female
  • protecting
    • female

Lifespan/Longevity

Woodland dormice live for approximately 5.5 years in the wild and may live 5 to 6 years in captivity.

Behavior

Woodland dormice are nocturnal and highly arboreal. They forage alone at night, mostly for insects and vegetation. In the fall, woodland dormice increase fat reserves by eating nuts and seeds prior to hibernating. During winter (May to August), when temperatures drop considerably, woodland dormice hibernate. During hibernation, they experience significant decreases in body temperature and mass. Their thermal neutral zone is between 29 and 35 °C, and they begin hibernating at an ambient temperature of about 15 °C. In the summer, woodland dormice may enter torpor during periods of decreased food abundance or when low or erratic temperatures occur. Woodland dormice are unique within their genus ( Graphiurus ), as they are the only African dormouse species to hibernate during the winter.

During periods of inactivity, African dormice spend time in their nests, which are typically made of plant material and found in tree cavities, shrubs, and rock crevices. To prevent heat loss, they curl themselves into a ball and wrap their tails around their bodies. Males, females, and juveniles may occupy an individual nest, and as many as 11 adults, consisting of both genders, have been found to occupy a single nest. African dormice use nests year round; however, nest type changes in relation to season. During the winter, they use nests that are better insulated and closer to the ground, than those used during the summer.

Males are territorial during the breeding season and establish a social hierarchy once they emerge from hibernation. Males scent mark and make warning vocalizations to demarcate and defend nesting territories, respectively. Although females scent mark territorial boundaries, they do not make warning vocalizations to ward off members of opposing groups.

• Key Behaviors
• arboreal arboreal
• scansorial
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• hibernation hibernation
• daily torpor
• solitary solitary
• territorial territorial
• social social
• dominance hierarchies dominance hierarchies

Home Range

Although little information is available on the size and composition of woodland dormice home ranges, its close relative, the spectacled dormouse ( Graphiurus ocularis ), has an average home-range size of 13.9 ha for males and 8.5 ha for females. Generally, there are about 10 woodland dormice per ha.

Communication and Perception

Woodland dormice make a variety of vocalizations including mating calls, territorial calls, alarm squeaks, and twittering sounds, for which the meaning is unknown. In addition, woodland dormice are likely to use visual, haptic (e.g., sense of touch), and olfactory cues to communicate with one another. Scent marking is likely used to establish territories and find mates, whereas vocalizations are probably used to find and defend mates, and defend territories.

• Communication Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

• Other Communication Modes
• scent marks scent marks

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Woodland dormice are omnivores, with dietary composition changing in relation to season. During spring, they eat primarily buds and insects, but occasionally eat small rodents and the eggs and young of small birds. In summer and fall, they eat fruit, seeds, and nuts to increase fat reserves for hibernation, and when food abundance is low, they may also eat bark and twigs.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore
• herbivore herbivore
  • frugivore frugivore
  • granivore granivore
• omnivore omnivore

• Animal Foods
• birds
• reptiles
• eggs
• insects
• terrestrial non-insect arthropods

• Plant Foods
• leaves
• wood, bark, or stems
• seeds, grains, and nuts
• fruit

Predation

Woodland dormice are preyed upon mostly by owls, and their remains have been found in the pellets of Mackinder's eagle owl ( Bubo capensis mackinderi ) in East Africa. Because they are both arboreal and nocturnal, woodland dormice have few predators.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Woodland dormice may play a role in the population dynamics of arthropods, which constitutes a significant proportion of their diet. Because they forage on various types of fruits and nuts, they may also be important seed dispersers. Finally, they are an important prey species for owls.

• Ecosystem Impact
• disperses seeds

Economic Importance for Humans: Positive

African dormice have no documented economic effect on humans. However, due to their high fat content, they are a preferred source of protein in some cultures. Human consumption of dormice is a well documented global phenomenon.

• Positive Impacts
• food food

Economic Importance for Humans: Negative

Woodland dormice are sometimes thought of as nuisances, as they occasionally make their nests in old furniture, roofs, electrical switch boxes, water pumps, and transformers. They can cause agricultural damage by raiding poultry farms and foraging on crops.

Woodland dormice are potential vectors for bubonic plague and monkeypox. A 2007 study in northern Tanzania found woodland dormice that were positive for Yersinia pestis , the bacterium that causes plague.

• Negative Impacts
• injures humans
  • carries human disease
• crop pest
• household pest

Conservation Status

Woodland dormice exhibit stable population trends and currently, there are no major threats to this species. The IUCN lists woodland dormice as a species of "least concern".

Additional Links

Encyclopedia of Life

Contributors

Jeanna Lodel (author), University of Wisconsin-Stevens Point, Stefanie Stainton (editor), University of Wisconsin-Stevens Point, Christopher Yahnke (editor), University of Wisconsin-Stevens Point, John Berini (editor), Animal Diversity Web Staff, Tanya Dewey (editor), University of Michigan-Ann Arbor.

References

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Haberl, W. 1999. "The Dormouse Hollow: Graphiurus" (On-line). The Dormouse Hollow. Accessed July 30, 2010 at http://www.gliratium.org/dormouse .

Holden, M., R. Levine. 2009. Systematic revision of Sub-Saharan African dormice (Rodentia:Gliridae: Graphiurus) Part ll: Description of a new speices of Graphiurus from the Central Congo Basin, including morphological and ecological niche comparisons with G. crassicaudatus and G. lorraineus. Bulletin of the American Museum of Natural History , 331: "314-355".

Madikiza, Z., S. Bertolino, R. Baxter, E. San. 2010. Nest box use by woodland dormice (Graphiurus murinus): the influence of life cycle and nest box placement. European Journal of Wildlife Research , 56: 1-10.

Makundi, R. 2008. Potential mammalian reservoirs in a bubonic plague outbreak focus in Mbulu District, northern Tanzania, in 2007. Mammalia: journal de morphologie, biologie, systematique des mammiferes , 72/3: "253".

Nowakowski, W., M. Remisiewicz, J. Kosowska. 2006. Food preferences of Glis glis (L.), Dryomys nitedula (Pallas), and Graphiurus murinus (Smuts) kept in captivity. Polish Journal of Ecology , 54/3: "369-378".

Rodel, H., W. Scholze, D. Kock. 2002. Diet of Mackinder's eagle owl Bubo capensis mackinderi in the alpine zone of Mount Kenya. African Journal of Ecology , 40: "283-288".

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