Australian possums have adapted very well to suburban living and are quite common in many areas. In some cases, they choose to move up in the social order and decide they'd rather live in a house than in a tree. If a little marsupial in the form of a possum chooses your house as his new residence and moves into the eaves or the ceiling, you may well feel flattered and have a warm, fuzzy feeling for a short time. You may believe that you (and your family) and the possum(s) can live in harmony. But, after a short time, you are bound to realise that possums are nocturnal, very vocal and totally lacking in consideration for others.
When you're planning a quiet night at home, the galloping horde above start playing 'murder in the dark'. This can make the pattering of rats and mice seem totally acceptable. Apart from their stomping around in what sounds like hobnail boots, possums have a variety of sounds. They can do heavy breathing that would put a telephone pest to shame, they have a deep, guttural cough and their domestic rows during the mating season would make one blush!
Apart from the inconvenience of being kept awake each night, possums chew wires and cables. Their urine creates stains on the ceiling and eventually there will be a very unpleasant smell as well.
Brushtail possums are the most common species found in Australian buildings. Ringtail possums will occasionally move into more salubrious quarters too. Under the National Parks and Wildlife Act, 1972-81, most possum species are protected by law. You will need a permit if you wish to get rid of your possum by trapping or euthanasia. A free permit can be obtained from the National Parks and Wildlife Service or from council or shire offices. A pest control firm can be contacted. Numbers are listed in the Yellow Pages and obviously there will be a charge for this service.
The same agencies that supply a permit may also hire out an open mesh trap. Alternatively a trap can be purchased from a hardware store although not all stores will stock them. The trap will need to be baited. A piece of apple or bread spread with peanut paste or honey is usually the first option. If your possum has superior tastes, you may need to try some other fruit or combination of fruits. Before positioning the trap, place the bait in the same area for a day or two. Once he has had a free meal or two he may be more inclined to enter an enclosed space for his next. Fix the bait firmly to the cage so that he can't have take-away. Then fix the trap in place and don't forget to check it each day.
Having successfully caught your possum, what are you going to do with it? So many problems! If you intend to kill it, do so in a humane manner. It can be released on private property providing the owner agrees. This is not always a good idea, at least not for the possum, as he will have to establish a range for himself in a hostile environment. Possums are territorial and there will be much tongue-lashing and many stoushes before everyone settles in their own patch again. New arrivals can upset the balance of native birds and animals. Releasing a possum into a National Park or metropolitan park is also not ideal for the reasons listed above. Wherever he is released, he will need access to somewhere to rest during daylight hours. Hollow trees are preferred as nest sites.
Once you are rid of your possum, you need to act quickly to prevent a new 'squatter' moving in. There is no point in sealing entry points until you are convinced that the area is possum-free. If you seal the entry points and a possum dies in the ceiling space, you will probably want to move out for a few weeks, if not months, while the smell dissipates.
Entry to the roof space can be prevented by lopping off overhanging branches. Trees close to the house can be fitted with metal 'collars' round the trunks. This will stop possums climbing the trunks and gaining access to the roof. Make the collar at least 60cm wide and 60cm from the ground. Fill in under the eaves and block all entry points. Possums can squeeze through very small openings. A determined possum, thwarted from entering 'his' roof space will make dogged efforts to get back, to the point of dislodging roofing tiles.
If having a possum living upstairs hasn't put you off possums altogether, you may like to supply a new home but outside your house. A nest box will save the possum the chaos and hassle of setting up a new home range. Besides, removing a possum from an area really just frees up that space for a new one to move on in. A nest box high in a tree will be perfectly acceptable provided it is protected from direct sun and rain.
Rough timber is a good choice for a nest-box. This gives good grip to young possums as they come and go. Scrap timber is fine. Planks of 19 to 25mm thickness are good as they will provide insulation. Don't use treated timber or chipboard unless there is no other option. Strong-smelling glues will deter possums from using the nest. Sheet metal should also be avoided.
A nest-box which is 300mm x 250mm x 550mm high will have a possum's blessing. Make an entrance hole 350mm from the floor with a diameter of 100mm. A lid on top should overhang the front and sides by at least 25mm. Slope the lid towards the back. A hinged lid will enable you to inspect the nest occasionally and perhaps clean it out even more occasionally.
Place the box on the south face of a tree and at least three metres above the ground. This should prevent any domestic pets from having a snack. Make sure the box is stable and upright so the possum feels secure.
Don't forget possums can scratch and bite if threatened or caught. By being slow and quiet with your movements, many possums learn to accept handouts from their (human) neighbours. If he moves into the box you've provided, give him time to settle in and don't disturb him. If he/she invites a mate home and they breed, too much attention or disturbance may see them abandon their young. If this happens, and you try to raise an abandoned possum, having one in the roof will seem like a walk in the park compared to raising a young one.