Dealing with large pests in the home
Australia's unique wildlife and climate can entice native animals including possums, snakes and rodents into your home, which can be harmful to your family and to your property.
Possums that seem cute and cuddly are some of the worst offenders, in particular the Brushtail possum, which is well-adapted to urban areas and likes warm, dry areas which often sees them end up inside roofs i.
As a general guide, possums move into roof spaces to nest as there may be no suitable natural habitat nearby. Possums can carry diseases and parasites, and can cause damage by chewing on electrical wires that can lead to short-circuiting and firesii.
To help them relocate out of your roof you can build a nest box for them. Place it in the roof for them so they can get used to it, then when they go outside to feed relocate the nest box to a nearby treeiii.
If you cannot get the possum out with encouragement, you should keep your distance and call a wildlife service that can safely trap the animal and release it outside. The laws that state how far from your home the possum can be released differ from state-to-state, however the general guide is that it should be very close by so that it is not in the territory of another possumiii, iv.
If you have had a possum in your roof space, once it and any other wildlife has been safely evacuated, you should try to possum-proof your roof. Check if there are gaps in eaves and look for indications of points of entry such as scratch marks, possum hair or urine/scent. Block off the entry points and bleach areas where scent is presentv.
20 of the 25 most venomous snakes in the world are found in Australia, including the Inland Taipan, which holds the top spotvi. Snakes play an important role in the Australian environment and can help keep other pests away, but you don't want them in your house or backyard - and they generally don't want to be therevii.
The most common time to find snakes is in spring when they are looking to mateviii, so if you do encounter one where it shouldn't be, stay at a safe distance several metres away and don't attempt to attack or move itix. If it's in the house you can open external doors, close internal doors, and give it a chance to leave.
If it doesn't seem willing to leave of its own accord, call a wildlife or reptile service - a snake catcher - to have it professionally removed. Snakes are protected, so it is against the law to harm them; furthermore, most snakebites occur when inexperienced people try to move themx.
In Australia there are over 60 species of Australian rodent, most of which are not regarded as pests. Across Southern Australia, there are three species of pest rodents all introduced after European settlement. They are the Norway rat (R. norvegicus), black or ship rat (Rattus rattus) and the house mouse (Mus domesticus)xi. As with possums, they can be a danger to both your family and property by carrying disease and chewing through wires, furniture and even wallsxii.
Because rodents are generally smaller, it can take time for them to be noticed. This increases risk of infestation because they breed so quickly. Infestation is more prevalent in winter when rodents seek warmth, and during extreme weather such as high rainfall or very dry conditions.
To avoid infestation, make your home less attractive to rodents by keeping it clear of rubbish, securing all food - including pet food - in strong sealed containers, blocking access to your home and cupboards, and ensuring rubbish bin lids are tight fittingxiii.
If you do have a rodent problem, as well as avoidance strategies you may need to use chemical control or traps. Extreme care must be taken with both methods to ensure the safety of children and pets, particularly using chemicals. Another disadvantage of poisoning is that the rodent may die from the poison in hard to reach places, such as inside wall cavities, causing odour and making the carcass difficult to removexiv.
To ensure your home remains pest-free, remove the means and reasons for unwanted animals to enter your home by keeping things clean and uncluttered. Regularly check walls, flooring and roofs for cracks and holes that may allow pests inside, as well as monitoring windows and doors. Don't leave food out and keep surfaces clean so that pests cannot see or smell food. If there is bush or scrub close by, this can increase the likelihood of unwanted animals, so perform regular maintenance to avoid unnecessary risks.
Organisations like the Royal Society for the Prevention of Cruelty to Animals (RSPCA), the Wildlife Information, Rescue and Education Service (WIRES) and the National Parks and Wildlife Service in your area can provide guidance online or over the phone and potentially send someone to help, particularly if the problem involves a native animal.
i Department of Sustainability and Environment, State Government of Victoria, 2013, Problems caused by possums in urban areas, http://www.dse.vic.gov.au/plants-and-animals/native-plants-and-animals/problem-wildlife/possums/possums-common-problems
ii Department of Environment and Conservation, The Government of Western Australia, 2009 Pest notes: Possums, http://www.subiaco.wa.gov.au/fileuploads/Possums1.pdf
iii Foundation for National Parks and Wildlife, Possums in your roof!, http://www.fnpw.org.au/resources/possum-in-the-roof
iv Fauna Rescue of SA, How to... deal with possums in your roof, http://www.faunarescue.org.au/articles.htm#roof
v Department for Environment and Heritage, SA Government, Possums in your Roof: Living with Possums in South Australia, http://www.environment.sa.gov.au/files/.../aus_possums_roof.pdf, p.2
vi Australian Venom Research Unit, Facts and Figures: World's Most Venomous Snakes, http://www.avru.org/general/general_mostvenom.html
vii Department of Environment and Heritage Protection, Queensland Government, Frequently asked questions, 8 January 2013, http://www.ehp.qld.gov.au/wildlife/livingwith/snakes/frequently_asked_questions.html
viii Snake Handler, Snake Species: Red Bellied Black Snake, http://www.snakehandler.com.au/?p=snake-species
ix Department of Environment and Conservation, The Government of Western Australia, 2013, Dealing with Snakes, http://www.dec.wa.gov.au/management-and-protection/animals/living-with-wildlife/dealing-with-snakes.html
x Royal Society for the Prevention of Cruelty to Animals (RSPCA), There's a snake in my backyard, what should I do?, 2011, http://kb.rspca.org.au/Theres-a-snake-in-my-backyard-what-should-I-do_443.html
xi Aplin, K.P., Singleton, G.R., CSIRO Sustainable Ecosystems, 2003, Balancing rodent management and small mammal conservation in agricultural landscapes: challenges for the present and the future, http://aciar.gov.au/files/node/451/mn96chapter1.pdf, p.81
xii SA Health, Government of South Australia, Rats: Prevention and control, http://www.health.sa.gov.au/PEHS/PDF-files/ph-factsheet-rats.pdf, p.1f
xiii SA Health, Government of South Australia, Rats: Prevention and control, http://www.health.sa.gov.au/PEHS/PDF-files/ph-factsheet-rats.pdf, p.2
xiv SA Health, Government of South Australia, Rats: Prevention and control, http://www.health.sa.gov.au/PEHS/PDF-files/ph-factsheet-rats.pdf, p.3