The Northern Brushtail Possum has a body length of approximately 35–55cm and a tail length of 25–40cm. The coat is typically grey in colour, however variations can include reddish brown, copper or chocolate brown. The fur is shorter and tail less hairy than T. vulpecula subspecies found in southern Australia (for example T. v. fuliginosus), and it has long, oval ears and a hairless underside. The subspecies is nocturnal, commonly nesting in tree hollows and forest canopy. Its diet consists mostly of leaves, flowers and fruits.
Northern Brushtail Possum |
Trichosurus vulpecula arnhemensis
Status: Vulnerable on the EPBC Act list
Government evidence of impact of climate change:
Australian Government, Conservation Advice, Trichosurus vulpecula arnhemensis
Climate change Increased Projected The temperature across northern Australia is projected to temperatures future rise under future climate change scenarios; resulting in a substantial increase in the number of days of extreme temperature and associated severe wildfire risk.
For example; a positive feedback loop may occur between invasive grasses and fire (the grass fire cycle); whereby invasive grasses increase fuel loads; leading to an increase in fire intensity; which reduces tree cover; which facilities an increase in invasive grasses (Rossiter et al. 2003).
Threat factor Threat type Evidence base and status Fire Frequent Known Small mammal ( 2kg) numbers have declined dramatically extensive; current in northern Australia in recent decades.
Altered fire regimes have been identified as a key driver of shrub loss in the mesic savannas of northern Australia (Russell Smith et al. 2012 Vigilante Bowman 2004); reducing food resources and habitat quality for species such as the Northern Brushtail Possum (Kerle 1985 Friend Taylor 1985 Woinarski 2004).
Numbers of feral cats in some areas of Northern Australia may have increased in recent decades because of changes to fire regimes; intensification of grazing; and dingo (Canis familiaris) reduction in some areas (Johnson et al. 2007).
Intense fire and grazing can amplify the impacts of predation by reducing understorey and ground cover (Oakwood 2000 Leahy et al. 2015) cat activity and hunting efficiency is known to increases in these areas (McGregor et al. 2014).
Increased and more variable rainfall is also amplifying the frequency and intensity of fire events. (CSIRO Bureau of Meteorology 2015).
Key threats to the Northern Brushtail Possum (especially introduced predators; interacting with changed fire regimes and land use; see Table 1) operate across its entire range; and it is likely that the population is continuing to decline due to these ongoing threats.
African Gamba Grass; Grader Grass and Mission Grass are also spreading through northern Australia; increasing biomass for fire fuel and probably making movement for the subspecies more difficult (Woinarski 2004).