A possum in your yard is almost always a Virginia opossum, and it’s almost always harmless. These animals are nocturnal, solitary, and generally uninterested in confrontation. In most cases, the best course of action is to leave it alone. It will likely move on within a day or two.
That said, finding an unfamiliar animal on your property raises real questions: Is it dangerous? Will it attack pets? Should you remove it? Here’s what you actually need to know.
What It’s Doing in Your Yard
Virginia opossums are opportunistic foragers. They eat insects, slugs, snails, fallen fruit, birdseed, pet food left outside, and garbage. If your yard offers any of these, it’s a buffet. They prefer wooded and forested areas but are highly adapted to suburban and urban environments, which means a fence won’t keep them out and their presence doesn’t mean something is wrong.
Opossums are nomadic. They don’t build permanent dens the way raccoons do. They shelter temporarily under decks, in brush piles, or inside sheds, then move on. If one has taken up residence, it’s because food or shelter is easy to access. Remove the attractant and the opossum will leave on its own.
The Tick-Eating Reputation
You’ve probably heard that opossums eat 5,000 ticks per season. That claim comes from a 2009 study at the Cary Institute of Ecosystem Studies, where researchers placed 100 larval ticks on captive opossums and found that more than 90 percent of the ticks were groomed off and swallowed. Opossums groom themselves fastidiously, like cats, and the researchers extrapolated that a single opossum could destroy roughly 5,000 ticks in one season.
The reality is more complicated. A 2021 review examined 23 published studies on opossum diets, including gut contents and scat analysis, and none found evidence of tick nymphs or adults being eaten by wild opossums. Researchers at the University of Illinois also examined gut contents of 32 opossum carcasses collected in Central Illinois. Ticks were found on the bodies, but no tick parts were found inside the animals. The original study used only five captive opossums and larval (not adult) ticks in a confined lab setting, which makes the extrapolation to wild behavior uncertain.
Opossums do eat plenty of other invertebrates, including beetles, cockroaches, slugs, and snails. They’re genuine pest controllers in that sense. The tick claim specifically, though, is on shakier ground than most people realize.
Are They Dangerous?
Opossums are not aggressive. When threatened, their first instinct is to hiss, bare their 50 teeth, and drool. It looks terrifying, but it’s a bluff. If the threat continues, they may enter a catatonic state, collapsing on their side with their tongue out and eyes glazed. This “playing dead” response is involuntary, similar to fainting. Their heart rate drops, their breathing slows, and they can remain in this state for minutes to hours. Despite appearances, they may remain partially conscious and will take advantage of an escape opportunity when they sense the threat has passed.
The fear most people have is rabies. Opossums have an unusually low body temperature for a mammal, sitting around 94°F to 97°F. The rabies virus needs a warmer host to replicate effectively, which makes opossums remarkably resistant to the disease. While no mammal is completely immune, rabies in opossums is extremely rare.
They can, however, carry other diseases. Leptospirosis and salmonella can be transmitted through their droppings, so avoid handling feces with bare hands. If you have horses, this is worth paying closer attention to: opossums can carry a parasite that causes equine protozoal myeloencephalitis (EPM), a serious neurological disease in horses. Keep opossums away from hay and horse feed.
Opossums and Pets
Dogs are far more likely to harass an opossum than the other way around. An opossum cornered by a dog will hiss and show its teeth, but physical confrontation is rare. The bigger risk is your dog injuring the opossum. Cats and opossums generally ignore each other, though you shouldn’t leave cat food outside, as it’s one of the top attractants for opossums and other wildlife like raccoons and rats.
How to Encourage One to Leave
If you’d rather the opossum move along, the approach is straightforward: make your yard less appealing.
- Remove food sources. Bring pet food indoors at night. Secure garbage lids. Pick up fallen fruit. Take down bird feeders temporarily.
- Eliminate shelter. Block access under decks and porches with hardware cloth. Clear brush piles and dense ground cover near structures.
- Use light and noise. Opossums are nocturnal and avoid well-lit, noisy areas. A motion-activated light or sprinkler near their shelter spot can make them uncomfortable enough to relocate.
Trapping and relocating opossums is legal in some states and illegal in others. It’s also often counterproductive. Relocated wildlife has poor survival rates in unfamiliar territory, and removing one opossum just opens the habitat for another to move in. Addressing the food and shelter is more effective long-term.
When an Opossum Needs Help
A healthy adult opossum in your yard doesn’t need rescuing. But there are a few situations where intervention is appropriate.
If you find an opossum that appears injured, is visibly sick, or is a juvenile less than 7 inches long from nose to rump (not counting the tail), it likely needs help. Contact a licensed wildlife rehabilitator in your area. It is illegal in most states to care for wildlife yourself without a license, and well-meaning attempts often cause more harm.
If you find a dead female opossum, check the pouch area for movement. Opossums are marsupials, and a mother killed by a car or predator may still have live babies in her pouch. If you see or feel movement, wrap the body gently in a towel and transport it to the nearest wildlife rehabilitator or veterinarian as soon as possible.
Orphaned baby opossums sometimes fall from their mother’s back and are found alone. Listen for a faint sneezing sound, which is the call they use to find their mother. If the baby is very small (under 4 inches nose to rump), it needs warmth immediately. Wrap it in a soft, ravel-free towel and place it near a low heat source like a heating pad covered with fabric. Do not offer cow’s milk. A diluted electrolyte solution like Pedialyte mixed with lukewarm water can sustain it until a rehabilitator takes over.
Why They’re Worth Tolerating
Opossums eat cockroaches, garden slugs, snails, and rodents. They clean up carrion and rotting fruit that would otherwise attract less welcome visitors. They’re quiet, they don’t dig up lawns, and they rarely stay in one spot for long. Their low body temperature makes them resistant to rabies, and their solitary nature means you’re unlikely to end up with a family of them under your porch.
If you’re in the United States, the animal in your yard is a Virginia opossum, the only marsupial native to North America. It’s recognizable by its white face, gray body, pink feet, and hairless tail. Australian possums are a completely different group of animals found only in Australia, Tasmania, and New Zealand, with bushy tails and fur that ranges from silver to red. The two are unrelated despite sharing a name. In everyday American English, “possum” and “opossum” refer to the same animal.