Geographic Range
Trichosurus caninus is an Australian marsupial that lives in the forests of southeastern Queensland, eastern New South Wales and eastern Victoria. (Strahan 95)
- Biogeographic Regions
- australian
Habitat
Trichosurus caninus lives in a variety of forest types in its range, although it pefers the wetter forests. It ranges from the southeastern corner of Australia midway up the eastern coast. This range encompasses a wide variety of climates and conditions and shows the ability of Trichosurus caninus to adapt to varying conditions. (Fischer et al 2000)
- Habitat Regions
- temperate
- terrestrial
- Terrestrial Biomes
- forest
Physical Description
Trichosurus caninus is a stocky possum covered with a thick grey to dark grey fur. Though its range varies in terms of termperatures and conditions, its color generally remains consistent (Walker 1999). It lacks the color variations of its relative Trichosurus vulpecula and the ears, while similarily rounded, are smaller. Its tail is almost as long as its body and covered with fur, except on the bottom near the terminal end. Adults range in length from 740-920 mm, including the tail.
Trichosurus caninus also possesses scent glands in its chin, sternal and anal areas. The sternal gland produces a clear secretion, as opposed to T. vulpecula whose sternal gland stains the chest fur of the animal. (Strahan 1995)
As in most marsupials, the females possess a forward opening pouch which they use to hold their young during the first few months of its life.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
Reproduction
Trichosurus caninus is thought to be polygynandrous as male and female territories often overlap considerably creating many breeding opportunities. However, because male and females have been caught in traps together, there is growing evidence that they may form mating pairs. Mates are attracted using both vocalizations and scent glands. (Walker 1999)
- Mating System
- monogamous
- polygynandrous (promiscuous)
Trichosurus caninus has a polyestrus breeding cycle averaging about 26 days. However, they usually breed in one of only 2 seasons--spring or fall. It is rare for the females to give birth more than once a year. The majority of the births occur between March and April. The females are sexually mature at age 2, however if they do mate and give birth at this young age, their young rarely survives. If the young do die, occasionally a second young is born. (Strahan 1995)
- Key Reproductive Features
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- viviparous
The female is the sole caretaker of the young. The young are born helpless after a gestation period is 15-17 days. The young then spends the next 5-6 months in the mother's pouch. After its time in the pouch, the young spends 2-5 months suckling before it is weaned. Once weaned, it continues to spend time in the mother's home range for 18-36 months until dispersing, with the females usually leaving earlier than males (Strahan 1995). However, sometimes the young stay in the mother's territory, which may cause mating by close relatives (Lindemayer et al 1998).
- Parental Investment
- altricial
- female parental care
Lifespan/Longevity
Trichosurus caninus is thought to live approximately 7 years in the wild. Generally, the females live longer than the males, and this is reflected in the findings that the oldest female survived 17 years, while the longest surviving male lived only 12 years. (Strahan 1995)
Behavior
Trichosurus caninus is generally a solitary animal even though the range of an individual may overlap with those of individuals of the opposite sex or even the same sex if there is a high population density. There is some evidence suggesting they may form pairs during breeding seasons. They maintain their territories through vocalization and scent markings.
Members of this species are arboreal and spend most of their time in the trees, especially during the day when they rest in the hollows. Being nocturnal, they come down from the trees at night in order to search for food among the shrubs and fallen logs. (Walker 1999)
- Key Behaviors
- nocturnal
- motile
- solitary
- territorial
Communication and Perception
Food Habits
Trichosurus caninus is an arboreal animal, but in order to feed it spends much of its time on the ground searching for its favorite foods amongst fallen logs and low shrubs. It is generally a herbivore and frugivore but will dine on insects on occasion. (Walker 1995)
Foods eaten include: shrub leaves, fruit, buds, fungi, bark and insects.
- Animal Foods
- insects
- Plant Foods
- leaves
- fruit
- Other Foods
- fungus
Predation
Trichosurus caninus is a very able climber and will climb to escape predators. It can also swim and will if it needs to escape (Strahan 1995). Additionally, as it is a nocturnal animal, it has excellent hearing and sense of smell.
Ecosystem Roles
Trichosurus caninus is a common small marsupial in its range. It provides a source of food for animals such as the python and the dingo and provides some seed dispersal through its eating of fruit.
- Ecosystem Impact
- disperses seeds
Economic Importance for Humans: Positive
Trichosurus caninus is often trapped for its very thick fur, however the pelt value is now much lower than in the past. This has led to a decrease in trapping efforts.
Economic Importance for Humans: Negative
There are instances where Trichosurus caninus has caused damage to pine plantations because it will strip the bark off trees or even ring tree. As Trichosurus caninus is fairly common, it is considered a pest in some of these areas (Strahan 1995).
- Negative Impacts
- crop pest
Conservation Status
Trichosurus caninus is very common throughout its range. While not as common as its close relative Trichosurus vulpecula , trapping seasons are used to control its population because it is considered a pest in some areas.
Additional Links
Contributors
Kevin Afflerbaugh (author), University of Michigan-Ann Arbor, Kate Teeter (editor), University of Michigan-Ann Arbor.
- Australian
-
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- 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.
- 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.
- monogamous
-
Having one mate at a time.
- polygynandrous
-
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- internal fertilization
-
fertilization takes place within the female's body
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- altricial
-
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
- female parental care
-
parental care is carried out by females
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- solitary
-
lives alone
- territorial
-
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
- herbivore
-
An animal that eats mainly plants or parts of plants.
- folivore
-
an animal that mainly eats leaves.
- frugivore
-
an animal that mainly eats fruit
- mycophage
-
an animal that mainly eats fungus
- tactile
-
uses touch to communicate
- chemical
-
uses smells or other chemicals to communicate
References
Fischer, J., D. Lindenmayer, H. Nix, J. Stein, J. Stein. 2000. Climate and Animal Distribution: a Climatic Analysis of the Australian Marsupial Trichosurus caninus. Journal of Biogeography , 28: 298-304.
Lindenmayer, D., R. Lacy, K. Viggers. 1998. Modelling survival and capture probablilities of the mountain brushtail possum (Trichosurus caninus) in the forests of south-eastern Australia using trap-recapture data. Australian Journal of Zoology , 245: 1-13.
Strahan, R. 1995. The Mammals of Australia . Chatswood, NSW: Reed Books for the Australian Museum Trust.
Walker, 1991. Walker's Mammals of the World . Baltimore, MD: John Hopkins University Press.