Possums generally don't dig through solid walls but are excellent climbers and squeezers that find or create holes to get into wall cavities, often scratching through drywall (gyprock) or chewing weak barriers to access shelter, food, or nesting spots. They enter through existing gaps, vents, or roof access, then move within the wall void, potentially causing damage by gnawing wires or insulation.
Possums are opportunistic creatures and can enter your home through gaps, holes, or cracks in your walls, roofs, and foundation. Here are some ways to prevent possums from entering your home and causing an infestation: Seal all entry points: Inspect your home for gaps or openings, and seal them with caulk or wire mesh.
While they do not dig underground dens, they are happy to take up residence in tree hollows, and the Ringtail Possum will build a soccer ball sized nest (drey) several metres above ground in dense foliage which they line with leaves, grass and soft bark.
Common Signs of Animals in Your Walls
Possums hate strong, pungent smells (like garlic, onion, peppermint, eucalyptus, mothballs, and ammonia), sudden disturbances (like motion-activated lights or sprinklers), and perceived predator threats, finding these elements unpleasant and unsafe, so they avoid areas with these strong deterrents, though they can get used to them if not moved.
Opossums are most active during spring and summer, wander widely in search of food, and rarely spend two consecutive days in the same spot. In the fall and winter, they occupy a more permanent nest lined with leaves.
I hear scratching inside my wall: what do I do?
Common signs of wildlife
Scratching or scurrying sounds in walls are often caused by rodents, bats, birds, or insects. Determining the pest involves considering the time of day, type of sound, and other clues. Professional help is often the best way to eliminate pests and prevent future issues.
Even though opossums aren't as dangerous as other wildlife, they can still damage your home, shed, and deck. They may also harm humans and pets if they feel threatened and try to defend themselves. Find a Critter Control near you.
Australian possums are nocturnal, meaning they become active after sunset, typically leaving their nests (like roof spaces or tree hollows) around dusk to forage for food, with activity peaking in the first half of the night before they return around dawn. You'll usually hear them start moving, scratching, or thumping around after dark, with noises often heard closer to 10 pm as they venture out.
What Are the Penalties for Breaking Possum Laws? Fines for breaching possum removal laws in NSW are substantial. If you trap, harm, or relocate a possum without authorisation, you could face: Fines of up to $6,600 for individuals.
These pests will make clicking noises when they're trying to attract mates and hissing or growling sounds when they feel threated. Baby opossums make noises that sound like sneezing when trying to get their parents' attention. Outside of these special circumstances, though, the pests rarely make audible sounds.
To get rid of possums fast, eliminate their food and water sources (trash, pet food, fallen fruit), secure entry points to your home (roof, vents, under decks) with mesh, and use strong deterrents like motion-activated lights/sprinklers, ammonia-soaked rags, or predator urine, while also trimming tree branches near your house to block access. For persistent issues, humane trapping and professional removal are options, but always check local wildlife laws first.
Possums come around houses seeking easy food, water, and safe shelter, drawn by unsecured trash, pet food, fallen fruit, compost, and cozy spots like roof cavities or woodpiles for warmth and protection from predators. They're opportunistic, so your yard becomes an appealing buffet and hotel, especially when natural food sources are scarce or your home offers ideal nesting.
Mice and rats commonly seek refuge in the cozy spaces in walls of your home. This is the most common place you will hear their quick light tapping and scratching sounds. FYI - walls act as a hidden highway system for them to move unseen through out a home.
If you are unable to simply reach down into the wall and retrieve the critters, you will need to cut a hole in the wall where they are trapped. Unless you are an experienced DIYer, this will likely mean calling a wildlife removal professional.
If you're noticing unusual droppings, scratching sounds, or persistent pests, now is the time to call pest control experts. Acting early protects your home, saves money, and ensures your family's safety.
Look for signs of rat or mouse infestation:
Common Signs of Mice Infesting Your Infrastructure
Below are the most common sounds made by mice and rats infesting wall spaces in your home. Light rapid scampering or pattering noises as rodents run through narrow cavities. Frenzied scratching against wooden studs, piping, and electrical wiring.
Hearing scratching in walls during the quiet hours can be unsettling. These noises are typically caused by rodents—most commonly mice or rats—that have entered your home. These pests are nocturnal, meaning they're most active at night when the house is quiet, and they feel safe to search for food and nesting materials.
Possums are nocturnal and highly vocal — especially in urban areas where space is limited. They use sounds to: Defend their territory. Attract a mate.
Food, habits, and habitat
Opossums are nomadic and tend to not den in the same area for consecutive nights. They den in abandoned burrows, tree cavities, hollow logs, and brush piles. They remain active year round and do not hibernate.
Or, a larger adult possum venturing out in the daytime may mean it is searching for a missing baby, or for food or water if it's been particularly hot or dry. Even if the possum in your yard isn't suffering from rabies, the creature may still appear to be struggling, which can be alarming for a homeowner to observe.