Living with Possums

The common Brushtail possum and to a lesser extent, the Western Ringtail possum  are two native mammals that may be encountered in and around urban areas in the south-west of Western Australia. The western ringtail is listed as speciall y protected (threatened)  under the Wildlife conservation Act 1950.

Possums have adapted well to living in and around urban areas and often take refuge in roof cavities instead of tree hollows.

This is usually an annoying experience, since possums are very noisy at night and over long periods may produce unpleasant odours and urine stains in the ceiling. However, rats and mice may also inhabit roof spaces and create a disturbance, especially during the winter months.

If the roof cavity is accessible, the easiest way to determine whether it is a rat, mouse or possum that has taken up residence is to find some droppings. Those of a possum are by far the largest, being about 2cm long and about 1cm wide. In comparison, those from a rat or mouse are narrower and can be less than 0.5cm to just over 1cm long. The lingering smell of rats and mice are different to that of a possum.
 

As possums are territorial, the removal of one possum from the roof will only leave a vacant possum-smelling space for another to take up residence. By careful observation at night it should be possible to find the place that a possum uses to enter the roof and, once this has been found, possums can be discouraged from taking up residence.

Deterring Possums

Block all potential access points to the roof except for the entry point that a possum has been observed using. Useful materials include sheet metal, vinyl, wood or wire netting with a mesh size of no more than 20mm, which should be fitted securely and snugly to prevent the animal from getting a claw hold and lifting the cover off the hole. Bricks are not recommended as possums are strong and have been known to loosen mortar or move bricks aside. It may also be necessary to trim or remove trees that provide access.

After dusk the possum will leave the roof to go in search of food at which stage the remaining entry point can be permanently blocked. A feeding platform may be useful for encouraging  possumsto a convenient observation point to confirm  that a possum has left the roof and it is safe to block off the last entry point. Pieces of fruit can be provided sparingly and while only attempting to exclude a possum from the roof.

Alternatively, fit a one way flap made out of metal or perspex to allow the possum out but not in. Cover the flap surrounds with metal to prevent possum claws from gripping and lifting the flap.

Information courtesy:
Department of Environment and Conservation