Silent dormice are not actually silent, they make quite a few vocalizations. When Dollman discovered the species in 1912, he chose the name to emphasize the small size of its ears. Although Dollman (1912) and Allen (1939) listed silent dormice as their own species, Misonne (1974) combined Graphiurus surdus and Graphiurus murinus into a single species. In 1981 Robbins and Schlitter (1981) listed Graphiurus surdus as its own species once again in a report on Cameroonian dormice, and Holden (1996) revised Graphiurus surdus in a report on Sub-Saharan dormice.
Silent dormice have excellent visual, auditory, and tactile senses. Typical vocalizations include whistles, chirping noises, various other twittering sounds, and a "surprisingly loud shriek" (Nowak, 1999). Woodland dormice, the closest relative of silent dormice, use scent marks to indicate territories and makes warning vocalizations to defend territories. Territorial encounters between male spectacled dormice involve loud vocalizations, raised claws, and threatening displays with their bushy tails.
Communication Channels: visual ; acoustic ; chemical
Other Communication Modes: scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
Not enough data are available to assign G. surdus a conservation status, they are considered data deficient according to the IUCN Red List.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
Dormice sometimes make themselves a nuisance by raiding poultry yards for food. African dormice can sometimes be found living in human habitations, especially in the upholstery of old furniture, but this occurs less frequently now because of competition with introduced rats.
Woodland dormice are vectors for bubonic plague and monkeypox. Given the extremely close relationship between woodland dormice and silent dormice, it seems likely that silent dormice may also be carriers of those diseases.
Negative Impacts: injures humans (carries human disease); crop pest; household pest
Because of their small size, African dormice in general have a relatively minor economic impact on humans. However, the human consumption of dormice for food is well-documented in Africa.
Positive Impacts: food
Given their dietary habits, silent dormice likely function as seed dispersers. They also probably play an important role in insect population dynamics and perhaps in owl population dynamics, if owls are in fact the primary predator of silent dormice as they are for the woodland dormice. Silent dormice are primary, secondary, and sometimes even higher-level consumers.
Ecosystem Impact: disperses seeds
Silent dormice are omnivores. They eat grains, seeds, nuts, fruits, insects, eggs, and even other small rodents.
Animal Foods: mammals; eggs; insects; terrestrial non-insect arthropods
Plant Foods: leaves; seeds, grains, and nuts; fruit; flowers
Primary Diet: omnivore
Silent dormice are found in western Africa, including southern Cameroon, Equatorial Guinea, Gabon, and north-eastern and south-central portions of the Democratic Republic of the Congo. The full extent of their geographic range remains unknown.
Biogeographic Regions: ethiopian (Native )
Silent dormice prefer moist lowland forests, specifically those classified by White (1983) as the wetter variety of the Guineo-Congolian rainforest. Only one specimen has been found in the drier type of Guineo-Congolian rainforest. They are agile climbers and largely arboreal.
Range elevation: 0 to 560 m.
Average elevation: 347 m.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: rainforest
No information is available specifically regarding the lifespan of silent dormice in the wild. It is likely they have a lifespan similar to that of other dormice, averaging just over 4 years. Silent dormice been recorded to live 5 years and 9 months in captivity.
Range lifespan
Status: captivity: 69 (high) months.
Silent dormice have compact bodies, and their relatively short, furred tails are frosted brown. Their coat is short and silky. The dorsal pelage is grayish-brown and composed of overhairs and short, fine guard hairs with no intermixed layer of underhairs. The hairs of the ventral pelage are dark gray and tipped with a white buff. Silent dormice have short, wide arboreal feet with six plantar pads. Compared to other species of Graphiurus, silent dormice have small ears, about 5 mm shorter than those of other South African dormice. Their faces are distinctive, with dark, mask-like markings around the muzzle and dark rings around the eyes. Silent dormice are not particularly sexually dimorphic. Females have four pairs of mammae: one pectoral, one postaxillary, and two inguinal.
Range mass: 18 to 34 g.
Average mass: 25 g.
Range length: 87 to 110 mm.
Average length: 99 mm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: sexes alike
No information is available specifically regarding predators of silent dormice. However, owls are the primary predators of woodland dormice and at least 19 species of owl are endemic in the geographic range of silent dormice. In general, African dormice tend to have few predators because of their nocturnal and arboreal natures.
When attacked, silent dormice bite with sharp incisors, vocalize loudly, and make threatening displays with bushy tails. Dormice are able to regrow their tails when lost.
Little information is available concerning the reproductive behavior of silent dormice, as their behavior has rarely been observed in the wild. Members of the genus Graphiurus, however, are territorial and solitary in general. When the summer breeding season begins, male African dormice become highly aggressive toward other males, suggesting polygyny.
Mating System: polygynous
In African dormice, most breeding occurs during the wet summer months (October through February). Normal litter size is between 3 and 4, but female rock dormice and woodland dormice give birth to as many as 6.
Average gestation length in woodland dormice, the closest relative of silent dormice, is about 24 days. At birth, woodland dormice weigh about 3.5 g. They reach sexual maturity the summer after their first hibernation.
Breeding interval: African dormice breed one or two times each year, usually during the summer months
Breeding season: Breeding occurs in summer, from October through February.
Range number of offspring: 1 to 6.
Average number of offspring: 3.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous
Little information is available regarding the parental investment of silent dormice. Newborns are altricial and, in most African dormice, they become independent after 4 to 6 weeks. Mothers provide protection and nursing in nests in shrubs and among the branches of trees. Paternal investment of African dormice is likely low to nonexistent, but no information is available on the subject.
Parental Investment: altricial ; female parental care ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)
The silent dormouse (Graphiurus surdus) is a species of rodent in the family Gliridae. It is found in Cameroon, Democratic Republic of the Congo, Equatorial Guinea, and Gabon. Its natural habitat is subtropical or tropical moist lowland forests.
The silent dormouse (Graphiurus surdus) is a species of rodent in the family Gliridae. It is found in Cameroon, Democratic Republic of the Congo, Equatorial Guinea, and Gabon. Its natural habitat is subtropical or tropical moist lowland forests.
