Possums in Adelaide homes: what an inspection finds (and the legal side of removal)

Two possum species share the Adelaide metro area. The common brushtail is large (around 3 to 4 kilograms), strong, primarily nocturnal, and the species responsible for almost all roof-void infestations. The smaller common ringtail (about 1 kilogram) is more often a backyard problem than a roof problem, building a dray nest in dense vegetation rather than a tucked-in roof corner.

Both species are protected under the South Australian National Parks and Wildlife Act 1972. It is illegal to trap, harm or relocate them without a permit. In practice this means Adelaide pest inspectors do not "remove" possums in the way they might handle rodents. They confirm activity, document the damage, and recommend a licensed wildlife handler who carries out exclusion under the regulated framework. The inspector is the diagnostic stage, not the action stage.

Possum pressure in Adelaide is strongly geographic. The inner-east and east heritage belt (North Adelaide, Walkerville, Kensington, Burnside, Beaumont, Glenside, Unley) sit on top of mature gum corridors that brushtails use as highways. Older roof construction in these suburbs (slate, terracotta, original timber framing) offers more entry points than modern Colorbond and concrete tile homes. Hills suburbs (Stirling, Aldgate, Mylor) face similar pressure from native bush.

Brushtails are agile climbers and only need a hole the size of a softball to enter a roof. Older Adelaide construction offers more of those holes than modern stock, which is why heritage suburbs see more activity.

Tile roof valleys and ridges: displaced or broken tiles along valleys, hips and ridges are the most common entry point. Mortar bedding ages out after 30 to 40 years and tiles loosen, leaving gaps that a possum slips through without disturbing them.

Eaves and fascia: warped or rotted timber fascia, broken eave linings, and oversized eave vents (anything wider than 25 mm) are walk-in access. Older homes with metal eave vents that have corroded out are especially exposed.

Whirlybirds and roof penetrations: broken or unflashed whirlybird ventilators, ageing skylights, and plumbing penetrations through the roof are common culprits. A possum can squeeze through a 70 mm round opening.

Chimneys: unflagged or capless chimneys are a vertical highway into the roof void. Heritage Adelaide sandstone homes with original chimneys are at highest risk.

Tree branches: any branch within 1.5 metres of the roof line is an access ramp. Trimming back overhanging branches is the single most effective preventative measure after sealing the building.

You can hear the activity: heavy thumping at dusk or dawn is almost always a possum. Book within a few days. Possums establish quickly and the cleanup cost grows the longer they nest.

You see the signs but not the animal: droppings, urine smell, insulation damage, or staining on the ceiling. Even if the animal has moved on, the access point is still open and the next possum will find it.

Pre-purchase: heritage Adelaide stock should always have the roof void inspected before settlement. A confirmed possum infestation post-settlement is yours to fix.

After tree removal or major garden works: displaced backyard possums look for new shelter. Inspect the roof voids of any property where mature trees have recently come down.

Renovation or extension involving the roof: opening up the roof during works gives a one-time chance to seal entry points cheaply. Inspect before and after the works to identify and close gaps.

Spring and autumn: Adelaide possum activity peaks during the spring breeding period (August to November) and the autumn weather transition (April to June) as animals seek warmer shelter. These are good periods for an inspection if you have suspicions.