Phascogale tapoatafabrush-tailed phascogale

Geographic Range

Phascogale topoatafa has a fragmented distribution, being found in various parts of Australia, including northern and southwestern Western Australia, northernmost Northern Territory, northern and southeastern Queensland, eastern New South Wales, the southern parts of Victoria, the Cape York peninsula, and isolated parts of South Australia (Nowak, 1991). There is some evidence of Phascogale tapoatafa in East Gippsland, though this has not been confirmed.

Habitat

Brush-tailed phascogales prefer eucalyptus forests in Australia for foraging grounds and nesting sites. They inhabit both humid and arid regions and dense to open forest (Nowak, 1999). Preferred habitat is open, dry schlerophyll forest with little ground cover and average rainfall between 500 and 2000mm (Strahan, 1983). Hollow trees are preferred for nesting sites (Nowak, 1999).

Physical Description

Brush-tailed phascogales are squirrel-sized marsupial mice with a head and body length (excluding the tail) of between 160-230mm. Tail length varies from 170-220mm, or roughly half of body length. They weigh between 110-235 grams, the largest wild specimen known weighed 311 grams. Males tend to be heavier on average than females and this sexual dimorphism first appears at the age of eight months (Nowak, 1999). They are a deep grey color on their dorsal surface and creamy, pale white on the venter. The tail is dark black and it is characterized by having long, black, silky hairs that cover the terminal portion. These long hairs are erected during normal activity producing a "bottle-brush effect" (Nowak, 1999). The erected tail hairs is thought to distract the attention of predators away from the body (Soderquist, 1994). The ears are large and almost lacking hair. Females have eight mammae and lack a true pouch. The pouch consists of a heavy fold of skin covered with coarse, brown hair.

  • Range mass
    110 to 311 g
    3.88 to 10.96 oz
  • Average basal metabolic rate
    0.694 W
    AnAge

Reproduction

Females nest in up to 30 different sites every year (Grzimek, 1990). Nests are found in hollow trees or tree stumps and under flaking bark. Competition is fierce for these limited resources Nowak, 1999). Mating takes place in early winter and males typically die after breeding at the age of 11-12 months. This is the largest known mammal in which males die after their first breeding season. It is believed that the energy expended in competition for mates leaves males susceptible to stress-induced diseases. Gestation period is roughly 30 days. Litters of seven to eight young are born and remain in the pouch for seven weeks. Young then stay in the nest until they are about 5 months old while the mother forages for food (Millis, 1999). Females raise one litter (sometimes two) in their lifetime, as they typically die in their second year. Females show dominance over males despite their smaller size and they seem to mate with a partner of their choice (MacDonald, 1984). The estrus cycle of females is roughly 40 days, and male spermatogenesis ceases before breeding while testosterone levels remain high (Millis, 1999).

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Average number of offspring
    6.4
    AnAge
  • Average gestation period
    29 days
    AnAge
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    365 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    365 days
    AnAge

Lifespan/Longevity

Behavior

Phascogale tapoatafa is an arboreal forager. Territories are marked with olfactory cues, such as urine and feces (Soderquist, 1995). Females are territorial but seem to tolerate their young daughters in their territory. Male territories overlap with females and other males. Female territories are between 30-60 hectares (average is 41), male territories average 106 hectares (Soderquist, 1995). When disturbed brush-tailed phascogales emit a low hissing sound that acts as an alarm. When confronted they emit a series of chit-chit sounds. They also have been observed slapping their front paws on the ground and rattling their tails (Soderquist,1995). This behavior may act as a warning to other members of the species or it may act as a distraction to potential predators.

Communication and Perception

Food Habits

Brush-tailed phascogales are mostly carnivorous. They hunt and kill small mammals, birds, reptiles, insects, spiders, and centipedes. They have been know to kill and eat chickens, and they generally avoid eating carrion. Phascogale tapoatafa can be arboreal and has been known to feed on the nectar of eucalyptus flowers (Nowak, 1999).

Economic Importance for Humans: Positive

Phascogale tapoatafa is considered effective at helping to control insect and rodent pest populations since it is a natural predator of these animals.

Economic Importance for Humans: Negative

They have been known to raid chicken farms but the benefits of pest regulation seem to outweigh any negative impact they may have.

Conservation Status

Brush-tailed phascogales occur are widespread but occur at low densities. Populations may be in decline but the causes are unknown. Preferred forest habitat is being destroyed and fragmented for agriculture, timber, firewood production, and mining (Nowak, 1999). Also, the introduction of feral species such as red fox and domestic cats have a negative influence on Phascogale tapoatafa populations as these two feral species act as predators. As a result, brush-tailed phascogales have disappeared from approximately half of their original range (Soderquist, 1995).

Contributors

Christoph Bugby (author), St. Lawrence University, Erika Barthelmess (editor), St. Lawrence University.

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.

scrub forest

scrub forests develop in areas that experience dry seasons.

sexual

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

tactile

uses touch to communicate

References

Grzimek, B. 1990. Grzimek's Encyclopedia of Mammals Vol.1. New York, New York.: McGraw-Hill Publishers Compound.

MacDonald, D. 1984. Encyclopedia of Mammals. New York, New York: Facts on File Incorporated.

Millis, A. 1999. Reproduction Biology of the brush-tailed Phascogale, Phascogale tapoatafa. Journal of Zoology, 248(3): 324-35.

Nowak, R. 1991. Walker's Mammals of the World, 5th Edition. Baltimore.: Johns Hopkins University Press.

Nowak, R. 1999. Walker's Mammals of the World, 6th Edition. Baltimore.: Johns Hopkins University Press.

Soderquist, T. 1995. Spatial Organization of the Arboreal Carnivorous Marsupial, Phascogale tapoatafa.. Journal of Zoology, 237(3): 385-98.

Strahan, R. 1983. Complete Book of Australian Mammals. London: Angus & Robertson Publishers.