Cercartetus nanuseastern pygmy possum

Geographic Range

Populations of Cercartetus nanus are found primarily in Tasmania, southeastern South Australia to southeastern Queensland, and small surrounding islands. On the mainland of Australia, C. nanus inhabits primarily the coastal areas of the southeast. (Turner 1983)

Habitat

A variety of shelters are used including shrubs, tree hollows, abandoned bird nests, and other bark-laced nests. Its small size allows C. nanus to live in small tree holes and nests. The bark nests that C. nanus contructs are usually small and spherical and are up to 6 cm in diameter (Turner 1983).

Physical Description

The adults have a body and head length of 75-100 mm. The tail is relatively long tail for its size, stretching to 75-105 mm. It is somewhat cylindrical in shape, with thick fur at the base and the hair becoming gradually sparser towards the tip. The color of the fur is gray to fawn on the dorsal side and whitish or slate colored on the underside. The hand is rather human-like, but the pad on each finger and toe is expanded into two lobes. The hallux is thumb-like and opposable (Walker 1975). The ears are relatively large and the eyes are quite dark and bulging ( http://www.komodo.com.au/wires/3116.htm).

  • Average mass
    40 g
    1.41 oz
    AnAge
  • Average basal metabolic rate
    0.311 W
    AnAge

Reproduction

There are two distinct breeding seasons. On mainland Australia breeding takes place from spring to autumn, while on Tasmania the season lasts from late winter to spring. The litter is size is predominantly four and occasionally five. Like most marsupials, Cercartetus nanus has young that are altricial at birth. The young nurse in the pouch for up to six weeks following birth and are then independent when they reach half of the mother's weight (Turner 1983).

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Average number of offspring
    4
    AnAge
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    190 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    190 days
    AnAge

Lifespan/Longevity

Behavior

Breeding usually occurs in nests located in tree hollows of the forest. The males of C. nanus often travel farther than the females, although both sexes are rather sedentary (Turner 1983). An agile climber and leaper, C. nanus is nocturnal. In the winter, to conserve energy, C. nanus remains torpid for extended periods, using stored fat in the tail as an energy source. Little if any social hierarchy exists, the adults are mainly solitary (Walker 1975).

Communication and Perception

Food Habits

Primarily an herbivore, C. nanus uses its brush tipped tongue to feed mostly on nectar and pollen from eucalypts, banksias, and bottlebrushes. In wet coastal regions, where fruit and blossoms are less abundant, a variety of insects is consumed, including flying moths, spiders, beetles, termites grasshoppers, and mantises. C. nanus is able to catch flying insects with one paw; these insects are eaten by first biting off the wings and then consuming the bodies. Feeding primarily occurs in short and quick bursts and is immediately followed by grooming (Turner 1983).

Economic Importance for Humans: Positive

This species aids in the pollination of certain flowers (Turner 1983). While many possums are valued for their meat and fur, it is unlikely that C. nanus hunted or eaten due to its small size (Lawlor 1979).

Economic Importance for Humans: Negative

Little information on the negative impact C. nanus has on humans exists, however it has been suggested that this species can damage valuable fruits or flower populations (Turner 1983).

Conservation Status

The logging industry of Tasmania poses a serious threat to this species. Regeneration burning and clear-cutting currently result in C. nanus being absent from affected areas. There are no specific management interventions, but it has been suggested that unlogged forest areas should be restricted from logging and burning ( http://www.erin.gov.au/environment/land/forest/cra/tas/env/marsup1.html#EasternPygmy).

Other Comments

It is interesting to note that C. nanus seldom vocalizes, but it can hiss loudly when disturbed or provoked. The longevity of C. nanus ranges from 4-8 years in the field (Turner 1983).

Also interesting to note, while generally a sedentary species, C. nanus has been known to travel up to 500 meters to obtain a specific bark for its nest (Walker 1975).

The common name dormouse is often used because C. nanus resembles the European dormouse, Myoxus glis. (Walker 1975).

Contributors

Corey Sides (author), University of Michigan-Ann Arbor.

Glossary

Australian

Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

References

Lawlor, T. E. 1979. Handbook to the Orders and Families of Living Mammals. Second Edition. Mad RIver Press, California.

Turner, V. 1983. The Australian Museum Complete Book of Australian Mammals. Angus and Robertson Publishers.

Walker, E. P. 1975. Mammals of the World. Third Edition. Johns Hopkins University Press, Baltimore.

http://www.erin.gov.au/environment/land/forest/cra/tas/env/marsup1.html#EasternPygmy

http://www.komodo.com.au/wires/3116.htm