The Virginia opossum, North America’s only native marsupial, is a common resident of suburban and urban environments. Often seen as a nocturnal scavenger, its presence in a residential yard raises questions about whether it is a helpful visitor or a troublesome pest. The opossum performs several beneficial ecological roles while also having the potential to create homeowner nuisances. Determining how to approach its presence near your home requires understanding its behavior and environmental contributions.
The Ecological Benefits Opossums Provide
Opossums are natural pest controllers. They are omnivores with a wide-ranging diet that includes garden pests like slugs, snails, and beetles, reducing the need for chemical interventions. They also consume small rodents, such as mice and rats, which helps limit the populations of these destructive or disease-carrying animals.
A significant benefit opossums offer is reducing the tick population. They are meticulous groomers and eliminate over 95% of the ticks that attach to them by ingesting them. A single opossum can kill as many as 5,000 ticks during a season, acting as an “ecological trap” for parasites that transmit Lyme disease.
As opportunistic scavengers, opossums consume carrion, helping to clean up the environment and prevent the spread of diseases associated with decaying remains. This scavenging behavior extends to fallen fruit and seeds, removing food sources that might otherwise attract less desirable wildlife like rats. They also have a high resistance to the venom of certain snakes, including rattlesnakes and copperheads, and will sometimes prey on them.
Opossums have a near-immunity to rabies. Due to their lower-than-average body temperature, the rabies virus struggles to survive in their system, making them highly unlikely to transmit the disease compared to many other common backyard mammals. This characteristic, combined with their generally docile nature, means they pose a very low threat to humans and pets.
Potential Nuisances and Property Concerns
Despite their ecological advantages, opossums can cause several nuisances. Because of their opportunistic feeding habits, they are strongly attracted to accessible food sources, often leading to raiding trash cans and scattering garbage. They will also consume pet food left outdoors and sometimes damage vegetable gardens or fruit crops, though they prefer overripe or fallen produce.
Another concern arises from their denning preferences. Opossums are nomadic and do not construct their own burrows, instead seeking shelter in ready-made, dark, and secluded spots. This often results in them taking up temporary residence under porches, decks, sheds, or even in accessible attics and crawl spaces.
When they den in these locations, it can lead to property issues, including structural damage if they widen entry points. Their presence results in unsanitary conditions due to droppings and urine, which may create foul odors, especially in confined spaces. While they are not destructive like raccoons or skunks, their messy feeding habits and latrine areas can be objectionable.
Safe Coexistence and Non-Harmful Deterrence
Managing an opossum presence can be achieved through simple, non-lethal modifications of the environment. The most effective strategy involves removing the primary attractants: food and shelter. All trash cans should be secured with tight-fitting, locking lids or bungee cords and stored until collection day to prevent nocturnal scavenging.
Any outdoor pet food and water bowls should be brought inside before dusk, and fallen fruits beneath trees should be promptly cleared. Securely covering compost piles and using enclosed bird feeders can eliminate further easy meals, which is often enough to encourage the opossum to move on to a new foraging territory.
To prevent denning beneath structures, homeowners can use exclusion techniques like installing heavy-gauge wire mesh or hardware cloth around the perimeter of decks, sheds, and porches. Before sealing an entry point, it is prudent to ensure the animal is not currently inside, which can be done by loosely stuffing the opening with newspaper and checking if it remains undisturbed after dark. Trimming low-hanging tree branches away from the roofline can also prevent them from accessing attics or chimneys.
If an opossum is encountered, it should be left alone, as they are generally timid and avoid confrontation. Their defense mechanism is called thanatosis, or “playing possum,” where they enter a comatose-like state that can last for minutes or hours. They may appear dead, but they are simply waiting for the perceived threat to pass. Humane deterrence, rather than trapping or lethal removal, is the recommended course of action, since removing one nomadic opossum often just makes space for another to take its place.