The mountain brushtail possum, or southern bobuck (''Trichosurus cunninghami''), is a
nocturnal
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
, semi-
arboreal
Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...
marsupial
Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsupials are endemic to Australasia, Wallacea and the Americas. A distinctive characteristic common to most of these species is that the young are carried in a po ...
of the family
Phalangeridae
The Phalangeridae are a family of mostly nocturnal marsupials native to Australia, New Guinea, and Eastern Indonesia, including the cuscuses, brushtail possums, and their close relatives. Considered a type of possum, most species are arboreal, ...
native to southeastern Australia. It was not described as a separate species until 2002.
Taxonomy
In 2002, based upon morphometric differences, the mountain brushtail possum, ''Trichosurus caninus'', was proposed to be reclassified into two distinct species. The northern form was to retain the binomial name ''T. caninus'', but was henceforth to be known as the
short-eared possum
The short-eared possum (''Trichosurus caninus'') is a species of marsupial in the family Phalangeridae endemic to Australia. Found north of Sydney, the species was once classed as a mountain brushtail possum
The mountain brushtail possum, or ...
. The southern population, prevalent in the
Victoria
Victoria most commonly refers to:
* Victoria (Australia), a state of the Commonwealth of Australia
* Victoria, British Columbia, provincial capital of British Columbia, Canada
* Victoria (mythology), Roman goddess of Victory
* Victoria, Seychelle ...
n
Alps
The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, Sw ...
, was to retain its already designated common name mountain brushtail possum, but assigned a new binomial, ''T. cunninghami''. However, genetic divergence between ''T. caninus'' and the putative ''T. cunninghami'' may not support a case for the establishment of a new species.
In 2005, a colony of bobucks was discovered in swamp coastal habitat in south-west
Gippsland, Victoria
Gippsland is a rural region that makes up the southeastern part of Victoria, Australia, mostly comprising the coastal plains to the rainward (southern) side of the Victorian Alps (the southernmost section of the Great Dividing Range). It covers ...
. A follow-up biodiversity survey uncovered a widespread yet previously unrecorded population of bobucks in coastal habitat and parts of inland Gippsland.
In view of these findings, the currently accepted name, "mountain" brushtail possum, is no longer accurately descriptive. One suggestion is to rename the northern group as the "northern bobuck" and the Victorian animals as "southern bobuck", ''T. cunninghami''.
Description
Both the mountain brushtail possum, ''T. cunninghami'', and its cousin the short-eared possum, ''T. caninus'', are generally reported to inhabit wet sclerophyll forest in south-eastern Australia along and to the south and east of the
Great Dividing Range
The Great Dividing Range, also known as the East Australian Cordillera or the Eastern Highlands, is a cordillera system in eastern Australia consisting of an expansive collection of mountain ranges, plateaus and rolling hills, that runs rough ...
of eastern Australia from southern Victoria to south-eastern
Queensland
)
, nickname = Sunshine State
, image_map = Queensland in Australia.svg
, map_caption = Location of Queensland in Australia
, subdivision_type = Country
, subdivision_name = Australia
, established_title = Before federation
, established_ ...
.
They typically dwell at altitudes greater than 300 metres. Bobucks are medium-sized (2.5–4.5 kg),semi-arboreal, nocturnal marsupials.
[
]
Diet and habitat
Habitat and dietary requirements of both the mountain brushtail possum and the short-eared possum are reported to be more specialised than those of their close relative the common brushtail possum
The common brushtail possum (''Trichosurus vulpecula'', from the Greek for "furry tailed" and the Latin for "little fox", previously in the genus ''Phalangista'') is a nocturnal, semiarboreal marsupial of the family Phalangeridae, native to Austr ...
, ''T. vulpecula''. As a result, the common brushtail possum has been able to colonise a greater variety of habitats than either of its bobuck relatives. For example, unlike common brushtails, bobucks are not known in urban areas and have been thought of as being obligately adapted to stable forest environments.
During the day, the mountain brushtail possum dens in tree hollows (or sometimes in dense ground cover) and at night emerges to forage. In mountain country the mountain brushtail possum is reported to depend mainly upon ''Acacia
''Acacia'', commonly known as the wattles or acacias, is a large genus of shrubs and trees in the subfamily Mimosoideae of the pea family Fabaceae. Initially, it comprised a group of plant species native to Africa and Australasia. The genus na ...
'' species for its diet and in particular the Silver Wattle, ''Acacia dealbata''. However, in lowland Gippsland there is no association of these animals with any particular type of vegetation: it is to be found in a variety of ''Eucalypt
Eucalypt is a descriptive name for woody plants with capsule fruiting bodies belonging to seven closely related genera (of the tribe Eucalypteae) found across Australasia:
''Eucalyptus'', '' Corymbia'', '' Angophora'', ''Stockwellia'', ''Allosyn ...
'' species stands or the Tea Tree. The mountain brushtail possum is known to feed at ground level and they are able to utilise hypogeal and epigeal fungi as well as ground-level plants food resources.[
The mountain brushtail possum is also reported to require tree hollows for use as dens. Indeed, both the easy availability of hollow-bearing trees and Silver Wattle are thought to determine the population density and distribution of the mountain brushtail possum in Victoria.
]
Reproduction
The mountain brushtail possum shows little sexual dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
.[ Mating occurs within a 2–3 week period during autumn (March–June). Female oestrus is highly synchronised, and most females will give birth to one offspring each year. Males do not appear to provide any care to the young. The young emerge from the pouch after several months and are then carried on the back of their mother. Over the summer (December to February), young begin to accompany their mothers on foot as a first step, as it were, to full independence. Neither males nor females will reproduce until they are at least two years of age. There is evidence that female offspring are often philopatric while young males have been found to disperse up to 8 km. Upon reaching reproductive maturity, the mountain brushtail possum will retain the same home range for life.
Its longevity is amazingly high: in fact it is perhaps the longest lived marsupial species.
Recent research][Martin, J. K. (2006). Den-use and home-range characteristics of Bobucks, T. cunninghami, resident in a forest patch. Australian Journal of Zoology 54(4): 225–234.] indicates that the mating system
A mating system is a way in which a group is structured in relation to sexual behaviour. The precise meaning depends upon the context. With respect to animals, the term describes which males and females mating, mate under which circumstances. Reco ...
of the mountain brushtail possum is variable. Intensive study of two mountain brushtail possum populations found that one of these populations was polygynous, while the other was monogamous. The two populations lived within 2 km of each other, yet the group dwelt in a linear habitat strip along a roadside that had escaped logging for over 100 years, whereas the monogamous population inhabited a forest patch that had been logged 40 years ago. To date it remains unclear whether this difference in mating system is because of the geographical shape of the habitat or the quality of its resources.
References
External links
{{Authority control
Possums
Mammals of Victoria (Australia)
Mammals of New South Wales
Mammals of Queensland
Marsupials of Australia
Mammals described in 2002