The North American Opossum (Didelphis virginiana) is the continent’s only native marsupial, yet it often faces significant negative public perception. Commonly viewed as a nuisance or a dirty animal, this creature is frequently misunderstood. Examining the facts about the opossum’s natural defenses, disease resistance, and ecological contributions reveals a much more nuanced and beneficial animal than its reputation suggests.
Behavioral Myths and Misconceptions
The opossum’s appearance, including its fifty sharp teeth—more than any other North American land mammal—often leads people to believe it is aggressive or dangerous. In reality, the opossum is a shy, non-confrontational creature whose primary strategy is avoidance or bluffing. When cornered, it will hiss and bare its teeth in a defensive display intended only to frighten a potential predator away.
The animal’s most famous defense is “playing possum,” or tonic immobility, an involuntary physiological response to extreme fear. Stress causes it to enter a comatose-like state that can last for several hours. During this state, the animal’s body goes limp, breathing slows, and it may secrete a foul-smelling fluid from its anal glands. This helps convince a predator that the animal is diseased or already dead.
Because the opossum’s gait is slow and awkward, it is poorly equipped to fight or flee. Attacks on people or pets are extremely rare, occurring only if the animal is cornered, handled, or intensely provoked. They prefer to retreat and avoid confrontation with humans or domestic animals.
Possum Health and Disease Resistance
Opossums are often mistakenly associated with high rates of disease, but they possess a notable resistance to certain pathogens, particularly the rabies virus. The opossum’s low body temperature, typically 94 to 97 degrees Fahrenheit, makes it difficult for the rabies virus to survive and incubate. While any mammal can contract rabies, the opossum is significantly less likely to carry the virus than many other common wildlife species.
The opossum’s low body temperature also contributes to its overall immune resilience, providing resistance to many other diseases and toxins. They are also diligent groomers known for exceptional hygiene. This meticulous self-cleaning behavior makes them highly effective in reducing the population of ticks. Scientists estimate that they kill over 90% of the ticks that attempt to feed on them, acting as natural pest control that limits the spread of tick-borne illnesses like Lyme disease.
Beneficial Scavengers: Their Role in the Ecosystem
The opossum’s omnivorous diet and scavenging habits are a net benefit to the local ecosystem, effectively turning them into nature’s cleanup crew. They consume a wide variety of food, including insects, rodents, snails, and slugs. By eating carrion, or dead animals, opossums help prevent the spread of disease and remove organic waste. They also actively prey on common garden pests like cockroaches, mice, and rats. Their ability to neutralize certain types of snake venom allows them to consume venomous snakes, contributing to a safer environment.
While their foraging can sometimes lead to nuisance issues, these conflicts are typically a result of easily accessible food sources. Coexistence is manageable with simple actions, such as securing trash cans with tight-fitting lids and bringing pet food bowls indoors overnight. Deterring them from seeking shelter can also be accomplished by trimming tree branches that lead to the roof and sealing any gaps in the home’s exterior.