A population study of the mountain brushtail possum (Trichosurus caninus) in the central highlands of Victoria

Abstract

Life-history attributes are described for the mountain brushtail possum (Trichosurus caninus) in mountain ash (Eucalyptus regnans) forest at Cambarville in the central highlands of Victoria, south-eastern Australia. The population was trapped on a regular basis between 1992 and 1995. Population density of T. caninus at Cambarville was high (2.3 animals ha–1). The adult sex ratio was female-biased (1.4 : 1) and the age class structure differed between sexes. There were more adult females than males in very old age classes (those animals assigned to Age Classes 7–9 and exceeding an estimated 10 years of age), whereas there were more males in the young adult cohorts (Age Classes 3 and 4). The breeding season was restricted to March–April, when a single young was produced. A second young was not produced if the first was lost. The survival of young from birth to emergence from the pouch showed strong between-year variation (30–80%). Sex ratios at birth were strongly male-biased (average = 2.6 : 1) but female young were far more likely to survive to advanced back-young stage. Breeding success of females at Cambarville was not influenced by the presence of semi-independent young from a previous year remaining in the natal territory. There was some evidence of senescence in breeding success among females in older age cohorts (Age Classes 7–9) and these animals did not successfully rear young. Many animals were trapped repeatedly at the same place, whereas others ranged over a much wider area (up to 3 ha). There was also considerable overlap between individuals in the spatial location of the areas where they were trapped.

High temporal variability in commensal Escherichia coli strain communities of a herbivorous marsupial

“…The species has hindgut fermentation with a well-developed caecum (Crowe and Hume, 1997). Female adults produce a single offspring per year during the 1 to 2 month autumn breeding season (Viggers and Lindenmayer, 2000). They commonly live for 8 to 12 years and reach sexual maturity at 2 to 3 years of age.…”

Fine‐scale refuges can buffer demographic and genetic processes against short‐term climatic variation and disturbance: a 22‐year case study of an arboreal marsupial

“…Adult mountain brushtail possums weigh 2.5–4.0 kg, live for up to 12 years and use dens over a mean 2.6 ha area at Cambarville. Adult females produce a single offspring per year, carried in the pouch from birth (March–April) until November (Viggers & Lindenmayer ).…”

“…Adult mountain brushtail possums weigh 2.5-4.0 kg, live for up to 12 years and use dens over a mean 2.6 ha area at Cambarville. Adult females produce a single offspring per year, carried in the pouch from birth (March-April) until November (Viggers & Lindenmayer 2000). This region is dominated by a 50-to 85-m overstorey of mountain ash (Eucalyptus regnans) trees, with varying dominant understorey vegetation that depends on topographic exposure and fire history.…”

The effect of sex‐biased dispersal on opposite‐sexed spatial genetic structure and inbreeding risk

“…Agile antechinus show strong sex-biased dispersal and female philopatry, with males recorded dispersing an average distance of 1390 m in fragmented habitat (Banks & Lindenmayer 2013). The mountain brushtail possum has overlapping generations with individuals commonly living for 8-12 years and breeding annually from an age of 2-3 years (Viggers & Lindenmayer 2000). By contrast, all agile antechinus males die after a single synchronous breeding season, and few females reach two years of age (Dickman 1982).…”