Living with Wildlife

Living with Brushtail Possums

The lively brushtail possum is one of Australia's most familiar marsupials, largely because they are highly adaptable to a wide range of natural and human environments. Their natural and preferred habitat is forest, where they nest in tree hollows. They will also cohabit with humans in cities and towns where they seek shelter, warmth and protection in the dark recesses of buildings. A favoured spot is between the ceiling and the roof and this can be a problem to some people. They can damage crops and gardens because they are partial to exotic plants, pasture grasses and vegetables as well as native plants.

Each year the Parks and Wildlife Service receives hundreds of calls for assistance to solve these possum problems and the following notes provide practical information to satisfy the house and landowner without harming the animal. Remember, brushtail possums are protected by law and cannot be bought, sold, taken or harmed except by permit.

Our web site also has full details of the biology of the brushtail possum.

Possums in your home
Is that noise in the ceiling a brushtail possum? Many times, the intruder turns out to be an introduced rat or mouse, which are declared pests. Sometimes both types of animals are involved and separate action is required. The following signs might help: Rats and mice make scratching, chewing and skittering noises. They have distinctive droppings; do not defecate where they are nesting and may chew electrical wiring. Rats also collect seeds and grasses. Brushtails do not. They make loud heavy, thumping sounds when walking, and distinctive guttural growls, screeches, hisses and coughs when disturbed. You can find out for sure by looking inside the ceiling with a flashlight during the day or observe your house just on dark when the brushtail emerges to feed.

Possum proofing
Catching and removing the animal never works -- not because the brushtail finds its way back but because it is replaced by another from nearby. We could go on removing them forever! Brushtails are strongly attached to their homesites and those which have been removed usually face a slow death, either because the release area is unsuitable or it is occupied by another brushtail which will defend its territory vigorously. Conflict for food and shelter usually means that the released possum dies. Whilst people object to brushtails living in ceilings or under floors, most wish them no harm. Since possums' chances of survival are best in their own territory, the following strategy is suggested:

• Find where the brushtail is getting in and out. More than one place may be involved.
• Make the necessary repairs to prevent entry. This can be done on a fine night between dusk and 10 pm when the brushtail possum is outside feeding. On wet and windy nights, a brushtail may leave later. Repairs need to be sound as brushtails are quite strong and will work hard to re-enter their shelter site. They can squeeze through a nine centimetre gap and are able to move loose tiles aside! If the brushtail has been trapped inside, its noisy attempts to escape will alert you. Baby brushtails always ride in their mother's pouch or on her back.
• Alternatively, repairs can be done during the day. The brushtail(s) must then be trapped inside the ceiling. Use sliced apple with a dash of vanilla as bait. Don't forget the necessary permit.
• Liberally splash the old entry areas with a strong smelling substance such as disinfectant, camphor or naphthalene to destroy the scent, otherwise the possum will try and re-enter.
• If you do not hear the brushtail for a few nights it has probably found a new home.
• Brushtails can be encouraged to stay in your yard by providing a nesting box, either a hollow log blocked at one end or a home-made nest (see diagram). It should be waterproof and placed four to five metres above the ground.

Possums on the farm and in the garden
The Parks and Wildlife Service encourages people to try preventative methods before more drastic methods of brushtail possum removal are allowed. If these methods fail, and serious economic damage is occurring, permits may be issued to shoot or poison.

Preventative planting
If planning a garden, try and select plant species which are unpalatable to brushtails such as prickly and spiny grevilleas and hakeas; tough and woody banksias and melaleucas (tea-tree) and plants with smelly foliage such as chrysantheums, mint bushes, geraniums and daisies.

Roses and fruit trees can be devasted unless protected. Trees can be protected by attaching a broad 40 cm band of metal around the trunk, 50 cm above the ground. Make sure that the brushtail cannot gain access from nearby trees!

Possum proof fencing
Possums readily climb fences but many can be possum proofed. Brush possums can only jump about 1 m vertically and cannot climb sheer walls. Therefore, a well made tin or paling fence (with the frame on the inside and the palings butted but not overlapped) about 1.5 m high will keep them out. Wooden fences will of course need a tin section -- at least 33 cm wide and 80 cm from the ground -- around the corners. A simple -floppy-topped- fence has proved very effective against possums climbing over ordinary fences. This is based on a netting, picket or other fence that possums cannot get through. The fence is fitted with a netting top that overhangs on the outside. As the possum (or cat or quoll) attempts to climb the overhang, it bends down and the possum will let go and fall to the ground. The floppy top then springs back to the original position (it is set on high tensile wire) ready for another assault.

Repellents
There are a range of chemical repellents which can be applied to individual trees or shrubs for temporary protection against brushtail and other possums. They are applied to the bark or foliage depending on the type of repellent used. It must be remembered that repellents give only short-term protection and give no protection to new growth. Repellents will never work on plants that are very attractive to animals.

The most common repellents are:

• Egg powder. Mix 200 g dried egg powder per litre of water with wetting agent and spray plants. This treatment is more effective than most but may cause leaf death if the plants are suffering from water stress.
• Blood and bone. Place it at the base of plants. This substance may attract dogs to the area because they like to eat the blood and bone.
• Mutton fat and kerosene. Mix nine parts melted fat with one part kerosene and leave to cool. The mixture is wiped lightly onto the stem and lower branches. Avoid the leaves as this treatment may cause browning on some species.
• Quassia chips extracts. Add 100 g of chips to 400 ml boiling water. Leave to stand for five minutes then add one litre of cold water and leave chips soaking for 24 hours. Strain and add wetting agent. Spray mixture onto plants.

The two most effective repellents available are egg powder and mutton fat mixed with kerosene even though both can cause some damage to the plants.

Trapping and relocation
Possums may be trapped and relocated if all else fails, but remember, if buildings are in good repair and possum-proofed then brushtails will be denied access and potential problems avoided. Extensive research has shown that most relocated possums quickly die, so we now prefer not to do it. A permit is required for any trapping and must be obtained from the Parks and Wildlife Service.

Orphaned or injured brushtail possums Orphaned or injured brushtail possums are often found. The Service has a network of carers to rehabilitate these animals if you cannot do so yourself. The Service has also produced a booklet about caring for injured and orphaned wildlife, and further information can be found on our web page on caring for orphaned wildlife. For any assistance, ring head office on (03) 6233 6556. Please return the possum to the bush as soon as possible. A permit is not required to rehabilitate brushtail possums.

Handle with care
Remember, brushtail possums are wild animals and though they look cuddly they can bite and scratch severely, especially when injured or afraid. Wear protective gloves or restrain the possum in a blanket or towel if you need to handle it.

Roles and values
Because brushtail possums are common and not too shy of humans they provide a wonderful link between urban people and the natural world. Their antics and acrobatics are a delight to watch and are educational. They are easy to see with a spotlight at night. They are our most common possum species and largest arboreal marsupial herbivore. Their fur is prized for its thickness and warmth and there is a small possum skin industry in Tasmania.

Possum conservation
Conservation is important even for common animals like the brushtail possum. This species occurs in all our National Parks. You can help by retaining areas of natural bush on your land and by learning to live with these animals. The Service is monitoring the population by conducting regular surveys around the State.

Our thanks to the A.C.T. Parks and Conservation Service, for use of artwork and information from their Living with Possums brochure.