Animal Diversity Web

Geographic Range

The range of Eupetaurus cinereus is restricted to the extreme northern portion of the Himilayas (Roberts 1977). All specimens have been collected from the rugged, mountainous region of northern Pakistan, but the range of E. cinereus is presumed to extend somewhat into Tibet (Nowak 1991).

• Biogeographic Regions
• palearctic
  • native

Habitat

Within its range, E. cinereus dwells on rocky terrain at and above the timber line (Grzimek 1990). It probably ventures into the isolated pockets of conifer forest to forage (Roberts 1977).

• Terrestrial Biomes
• mountains

Physical Description

Eupetaurus cinereus is known entirely from about ten specimens (Grzimek 1990). Like other flying squirrels, it has elastic membranes on each side of the body connecting the fore and hind legs (Prater 1965). It is slightly larger in size and has a shorter, bushier tail than the Giant Red Flying Squirrel (Petaurista petaurista albiventer) which also inhabits Pakistan. Two E. cinereus specimens measured 61 cm and 51.5 cm, respectively, from head to base of tail. The larger specimen had a tail length of 38 cm, while the smaller had a tail measuring 48 cm. The body is covered by a dense coat of straight, silky hairs. The dorsal pelage appears blue-gray, while the underside is pale gray in color. Creamy white hairs cover the throat and ears, and dense, black fur covers the soles of the feet except for the naked, pinkish brown toe pads. The tail, bearing hairs of about 7.6 cm in length, is large and bulky and may be as broad as the animal's body (Roberts 1977). Molars have relatively high crowns compared to the low crowned, brachyodont molars of all other flying squirrel genera, and unlike other flying squirrels, the claws of E. cinereus are blunt and adapted for rocky terrain instead of an arboreal lifestyle (Blanford 1891).

• Other Physical Features
• endothermic
• bilateral symmetry

Reproduction

Very little is actually known about the reproduction of E. cinereus. An immature specimen was collected on April 17. This seems to indicate that breeding occurs early in the spring and that two litters may be produced each season (Roberts 1977). However, such conclusions are little more than speculation.

• Key Reproductive Features
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual

Behavior

Despite the harsh winter conditions in the northern Himalayas, E. cinereus does not hibernate. It stays active all winter, searching for mosses and lichens on rocks and venturing into the boreal forests when buds and cones become available. Because of its large size and blunt claws which appear useless for gripping bark, E. cinereus seldom, if ever, ventures into trees. In general, flying squirrels are nocturnal (Prater 1965), but the specific habit of E. cinereus is unknown.

• Key Behaviors
• motile

Communication and Perception

• Perception Channels
• tactile
• chemical

Food Habits

The high crowned molars of E. cinereus indicate a diet of extremely rough vegetation. It appears that much of the diet consists of buds and cones, particularly those of the native spruce, Picea morinda. At high elevations, Picea morinda begins producing buds in April and cones in late summer. The cones are shed in winter when the ground is covered by snow, meaning that, by early spring, food for E. cinereus may be in extremely short supply. During these hard times, E. cinereus probably turns to mosses and lichens as a main food source (Roberts, 1977).

Economic Importance for Humans: Positive

Eupetaurus cinereus has never been common enough or well known enough to be utilized for economic gain.

Conservation Status

Eupetaurus cinereus was first described by Oldfield Thomas in 1888. Since that time, only a handful of specimens have been collected. Photographs of the species are equally rare. Because it inhabits a very limited range in an exceedingly hostile climate, our knowledge of E. cinereus is too limited to accurately determine the status of the population. However, it is reasonable to assume that E. cinereus has always been a relatively rare species, existing at low population densities (Roberts 1977).

• IUCN Red List

  Endangered
  More information

Other Comments

Very little is known about E. cinereus, but it is of great zoological interest due to its restricted geographical distribution and unique adaptations that allow it to survive in a habitat which is intolerable to other flying squirrels (Roberts 1977).

Contributors

Eric Palkovacs (author), University of Michigan-Ann Arbor.

References

Blanford, W.T. 1891. Fauna of British India. Taylor and Francis, Red Lion Court, Fleet Street, London.

Grzimek, B. 1990. Grzimek's Encyclopedia of Mammals. Volume 3. McGraw-Hill Publishing Company, New York.

Nowak, R.M. 1991. Walker's Mammals of the World. Fifth Edition. Volume 1. Johns Hopkins University Press, Baltimore.

Prater, S.H. 1965. The Book of Indian Mammals. Second (Revised) Edition. Bombay Natural History Society, Bombay.

Roberts, T.J. 1977. The Mammals of Pakistan. Ernest Benn Limited, London.