Common Brushtail Possum

BIRD: linking the biodiversity community

Category: Marsupials

The Common Brushtail Possum (Trichosurus vulpecula) is the largest possum, and perhaps the most familiar of all marsupials: one of the very few that thrives in cities as well as a wide range of natural and human-modified environments.

An adult Common Brushtail is between 350 and 500 mm long, with a well-furred, moderately prehensile tail of 250 to 400 mm; weight varies from around 1.2 up to 4.5 kg for a large male. The very loud hissing, crackling territorial call of the male Common Brushtail has a nightmare quality.

Like all possums, it is nocturnal and omnivorous: in the wild it mostly eats leaves, but supplements this with fruits, flowers, buds, and whatever else is available. Common Brushtails have a notable tolerance to plant toxins; several of their favoured trees are poisonous to most creatures. Around human habitations, Common Brushtails are inventive and determined foragers with a liking for fruit trees, vegetable gardens, compost heaps and rubbish bins.

During the day Common Brushtails sleep in a nest in a hollow tree or any other convenient place, notably ceiling spaces that are not securely sealed. Although primarily aboreal and not found in places without trees to provide refuge, they spend a good deal of time on the ground.

In the temperate south most breeding takes place in autumn with an additional minor breeding season in spring. In the north, breeding is opportunistic and depends on available food supplies. A single young is born, and spends four or five months in the pouch, followed by another month or so on the mother's back. Dispersal in search of a home range is the critical time for a young brushtail: if this is survived, life expectancy in the wild is up to ten years. Predators include cats, foxes, Dingos, larger pythons and goannas, and the Powerful Owl.

The Common Brushtail can be found almost anywhere where there are trees, particularly in woodlands and open forests, and in cities. Abundant in south-eastern Australia, it is rare in the central deserts and appears to be declining in other areas. In 1840 European settlers aiming to establish a fur industry introduced the Common Brushtail to New Zealand, where there are no native mammals other than bats. This proved to be an ecological disaster on a grand scale: there are now about 60 million Common Brushtail Possums in New Zealand, they do great damage to native species, and there is no reasonable hope of eradication.