Sminthopsis crassicaudatafat-tailed dunnart

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Geographic Range

This species occurs in the extreme southern portions of Queensland, Australia.

Physical Description

Fat-tailed dunnarts typically have a head and body length of 64- 110 mm, and a tail length of 51-12 mm. They range from buffy to brownish in color, and have dark patches on their ears and head.

  • Average mass
    16 g
    0.56 oz
    AnAge
  • Average basal metabolic rate
    0.121 W
    AnAge

Reproduction

This species is polyestrus. Females may breed and raise litters continuously for up to six months if environmental conditions are favorable. Nearly all of the breeding in this species occurs between July and February. Gestation ranges from 13 to 16 days, and litters of up to ten young may be produced. The young first protrude from their mother's pouch at the age of 37 days. They disperse from their natal range when they are 65-69 days old. Females attain sexual maturity more quickly than males. They are capable of becoming pregnant when they are 155 days old. Males, however, are not capable of breeding until they are 159 days old.

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Average number of offspring
    7
    AnAge
  • Average gestation period
    14 days
    AnAge
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    115 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    159 days
    AnAge

Lifespan/Longevity

Behavior

Fat-tailed dunnarts are nocturnal and appear to live in small groups. Although little is known about their social system in the wild, captive study has shown that females are not receptive to the presence of males after they have given birth to a litter. Males housed with females who have litters are often killed by the females. This suggests that females with young may be territorial and solitary in the wild. Fattailed dunarts, like many marsupials, have poorly developed thermoregulatory abilities. In the colder months, they may enter into a thermoregulatory mutualism with Mus musculus. Huddling together for warmth, both species are able to reduce their energetic costs. Mixed species aggregations are common during the winter, and there is a low incidence of natural torpor.

Communication and Perception

Food Habits

The fat-tailed dunnart eats a variety of grasshoppers, moths, and beetles.

Conservation Status

Contributors

Nancy Shefferly (author), Animal Diversity Web.

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.

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

Collins, L.R. 1973. Monotremes and Marsupials. Smithsonian Institution Press.

Nowak, R.M. and J.L. Paradiso. 1983. Walker's Mammals of the World, Fourth Edition. John Hopkins University Press, Baltimore, London.