The Virginia Opossum is the only marsupial native to North America, often encountering humans in suburban and urban environments. These nocturnal animals are frequently viewed with suspicion due to their appearance and nighttime scavenging habits. While they can cause minor nuisances, their ecological role often provides unexpected benefits to the yard ecosystem. This evaluation considers the damage they inflict, the health risks they pose, and the positive contributions they make.
Assessing Property and Garden Damage
The most frequent complaint against opossums involves nuisance activities related to their diet as opportunistic omnivores. They are notorious for raiding unsecured garbage cans, overturning them to access food scraps, which creates a significant mess. Pet food or bird seed left outdoors overnight is also a strong attractant that can lead to repeat visits.
Direct damage to vegetable gardens is generally minor, as opossums prefer decaying fruit and pests over fresh produce. However, their search for insects and grubs can sometimes result in small, shallow holes dug into lawns and mulched areas. This digging is a secondary result of their pest-control efforts.
Opossums do not construct their own burrows but seek out ready-made shelter, which can sometimes lead them under decks, porches, or sheds. While they are not destructive chewers, their presence can be an annoyance and may result in a buildup of nesting materials and waste. They are non-territorial and often only use a den site for a few days before moving on, limiting the long-term impact on any single structure.
Disease Transmission and Safety Profile
The concern that opossums are carriers of disease is often overstated, particularly regarding rabies. Opossums possess a naturally low body temperature, typically under 96°F, which makes their bodies an unsuitable host environment for the rabies virus. This physiological trait means they are highly resistant to the virus, making rabies infection in opossums extremely rare compared to other common backyard mammals.
A more realistic health concern involves parasites, as opossums can carry fleas, ticks, and internal parasites like roundworms. They are also definitive hosts for the protozoan that causes Equine Protozoan Myeloencephalitis (EPM), a neurological disease that affects horses.
Their famous defense mechanism, “playing possum,” is an involuntary physiological response to severe fear, where the animal enters a catatonic state. This behavior is a non-aggressive attempt to deter a predator by appearing dead. Opossums are generally docile and will retreat rather than engage, reserving bites and scratches for when they are cornered or handled.
Ecological Role and Surprising Benefits
Opossums provide substantial benefits to the local ecosystem, largely through their role as natural pest controllers. They are effective at reducing tick populations on a property, consuming an estimated 3,000 to 5,000 ticks during a single season. This high rate of tick consumption occurs because opossums are fastidious groomers, often ingesting the vast majority of ticks that attempt to feed on them.
Their broad omnivorous diet also includes many other garden pests, such as slugs, snails, and various insects. By consuming these invertebrates, they help keep garden pest numbers in check, offering a form of natural biocontrol.
Opossums also serve as efficient scavengers, cleaning up carrion, which reduces the presence of decaying animals that could otherwise attract larger predators or spread disease. The consumption of fallen fruit, berries, and nuts also contributes to the cleanliness of a yard, eliminating food sources that could attract other wildlife.
Non-Lethal Methods for Coexistence
Managing the presence of opossums focuses almost entirely on removing the attractants that draw them into the yard. Securing all outdoor food sources is the most effective action, meaning trash cans should have tight-fitting or locking lids. Pet food and water bowls should be brought indoors before dusk, as opossums are nocturnal feeders.
Exclusion methods prevent them from taking up residence in sheltered spots. Block access points beneath decks, sheds, and porches with wire mesh or solid barriers. This must be done only after confirming the animal has left the area. Using motion-activated sprinklers or lights can provide a mild deterrent, as opossums prefer dark and quiet environments.