The Virginia opossum, Didelphis virginiana, is the only marsupial found across North America, ranging widely from Central America into Canada. As a nocturnal animal, it relies on a flexible, opportunistic diet, which has allowed it to thrive in diverse environments, from woodlands to urban neighborhoods. This adaptability means the opossum is classified as a generalist omnivore and scavenger, consuming both animal and plant matter. This wide range of foods is the primary reason this species has been so successful in coexisting near human populations.
The Natural Omnivore: Wild Diet Staples
In natural, undisturbed habitats, the opossum’s diet is heavily focused on invertebrates, which they locate using their keen sense of smell. These animals consume slugs, snails, earthworms, and various insects, including beetles and grasshoppers. This predation on common garden pests makes the opossum a natural contributor to ecological pest control.
They also actively hunt small vertebrates, consuming mice, meadow voles, frogs, and bird eggs when available. Opossums are also known to prey on small snakes, a capability aided by their high resistance to the venom of pit vipers like rattlesnakes and copperheads. This unique biological trait allows them to take advantage of a food source unavailable to most other small mammals.
Carrion, or dead animals, is a frequently consumed part of the wild diet, earning them the reputation of “nature’s cleanup crew.” This scavenging behavior is important for maintaining a clean ecosystem and is a significant source of calcium, which they obtain from consuming bones. Plant-based foods round out their natural intake, especially during late summer and autumn, consisting of wild berries, apples, nuts, and seeds.
Suburban Adaptations: Foraging Near Human Habitation
The opossum’s naturally opportunistic nature means it quickly exploits the abundant food sources associated with human settlements. They are often seen foraging in residential areas, where they rely on discarded items rather than hunting for wild foods. One of the most common suburban food sources is pet food, particularly dry cat or dog kibble left outside overnight in bowls.
Garbage cans and compost piles are also frequent targets because they contain a rich mix of accessible food waste and discarded scraps. This scavenging behavior is a direct result of their ability to eat almost anything they encounter, especially items that require minimal effort to obtain. Securing trash lids and bringing pet food inside after dark can significantly reduce their presence in a yard.
In cultivated areas, opossums will readily raid gardens for fallen fruit, vegetables, and cultivated crops. They are also attracted to bird feeders, consuming spilled seeds, nuts, and suet intended for birds. While these items provide calories, a diet based solely on high-fat bird seed or processed human scraps can be nutritionally unbalanced for the animal.
Foods to Avoid (Harmful and Toxic Items)
Providing opossums with an unbalanced diet, especially one high in processed food, can lead to malnutrition, even if the animal appears well-fed. Foods high in sugar, sodium, or fat, such as fried snacks and junk food, can cause long-term organ damage and obesity. Bread and similar grain-heavy products should also be avoided because they offer little nutritional value and can fill the animal without providing vitamins and minerals.
Dairy products are particularly harmful because opossums are largely lactose intolerant, meaning they lack the enzyme needed to digest milk sugars. Consumption of dairy can lead to gastrointestinal distress and dehydrating diarrhea. Even small amounts of certain human foods contain toxins that are dangerous to their systems.
Chocolate, for instance, contains theobromine and caffeine, which opossums cannot metabolize efficiently, leading to nervous system issues and potential cardiac arrest. Similarly, onions, garlic, and chives contain thiosulphate compounds that can damage red blood cells, potentially causing hemolytic anemia. Avocado is also toxic, especially the skin and pit, as it contains a fungicidal toxin called persin, which can interfere with the function of their heart and lungs.