Animals Wildlife 10 Things You Didn't Know About Opossums By Melissa Breyer Editorial Director Hunter College F.I.T., State University of New York Cornell University Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others. our editorial process Melissa Breyer Updated April 12, 2021 Treehugger / Lara Antal Share Twitter Pinterest Email Animals Wildlife Pets Animal Rights Endangered Species The Virginia opossum has the distinction of being both the only opossum and the only marsupial native to North America. Colloquially called possums, Virginia opossums should not be confused with arboreal marsupials of Australia and New Guinea that are also known as possums. Virginia opossums are found in North America east of the Rockies and along the western coast of the United States, as well as in Central America. According to the IUCN, the population of Virginia opossums is increasing and they are not considered at risk. Due to their rat-like appearance, opossums have a less-than-stellar reputation. But these clever nocturnal critters have a lot going for them. They have a natural tolerance for snake venom and they eat parasitic ticks and garden pests. Just like their marsupial relatives, female opossums, called jills, carry joeys in their pouches. From opposable toes to an ability to feign death in an instant, discover the most fascinating facts about the opossum. 1. Opossums Are Smart Critters Although many people think opossums are not the sharpest knives in the drawer, there are several areas of intelligence in which they soar. For one, they have a remarkable ability to find food and to remember where it is. When tested, opossums outscored rats, rabbits, cats, and dogs — but not humans. They also can find their way through a maze more efficiently than rats and cats. 2. They're All Thumbs Just like humans and other primates, the opossum has the equivalent of opposable thumbs. Called a hallux, each of the opossum’s big toes on its hindfeet are opposable; they stand apart from the other toes in a way that looks very similar to a human hand and thumb. The hallux provides the opossum with better grasping and climbing skills than most other mammals. Unlike the opossum's other digits, the hallux is the only one that does not have a claw. 3. They Have Impressive Tails Jay Ondreicka / Shutterstock Opossums have prehensile tails that they use like a hand or a fifth appendage. Their tails are long — nearly as long as the opossums themselves — and are hairless, much like a rat’s tail. Their tails allow them to grasp, carry, and wrap around things like tree limbs. The tail also aids in balance. Opossums can hang from their tails, but only for brief periods. 4. They Are Opportunistic Omnivores The opossum's normal diet consists of carrion, rodents, snakes, insects, snails, slugs, birds, eggs, frogs, plants, fruits, and grains. If given the opportunity, opossums will also eat human food, pet food, and trash. They can adjust their diet based on season and location. Sanitation workers of the wild, opossums have an unusually high need for calcium, which incites them to eat the skeletons of rodents and roadkill they consume. 5. They Have Natural Defenses Joe McDonald / Getty Images When threatened, opossums run, growl, belch, urinate, and defecate. And when all else fails, they “play possum” and act as if they’re dead. It is an involuntary response (like fainting) rather than a conscious act. They roll over, become stiff, close their eyes (or stare with their eyes open), and bare their 50 small teeth. Saliva forms around the opossum’s mouth and it secretes a foul-smelling fluid from its anal glands. The catatonic state is more common in young opossums and can last for up to six hours. Adult animals are more likely to stand up to enemies or run away at speeds of around 4 miles per hour. 6. They Carry Their Young in a Pouch Just like other marsupials, female opossums, called jills, care for their offspring, called joeys, in their pouches. Young opossums are tiny at birth — about the size of a bee — and are blind, deaf, and furless. After a short gestation period of less than two weeks, the joeys crawl into their mother’s pouch where they remain for a couple of months. After they leave the pouch, joeys remain close to their mother, often riding on her back for another few months until they become fully independent. Male opossums, known as jacks, do not participate in the care of the young. 7. They Are Always Grooming While opossums may appear unkempt, they are actually meticulous about self-care. When they’re not actively searching for food or sleeping, opossums are grooming themselves. Just like cats, opossums follow the same pattern of licking their paws and wiping their face. They clean their entire bodies, from head to tail, using their claws to comb their fur and remove insects to munch on. Female opossums are particularly fastidious about keeping their pouch clean, particularly when caring for their young. 8. They Have Natural Immunity It’s a common misconception due in part to their appearance that opossums must be harbingers of disease. But in the case of rabies, opossums are rarely carriers of the deadly virus because of their naturally low body temperature. In comparison to other wild animals, opossums are much less likely to carry rabies than bats, raccoons, and skunks. However, opossums can pass diseases like leptospirosis or Salmonella to humans through their excrement. And they are frequent spreaders of fleas to domestic animals. While opossums are often stung by bees and scorpions, they have an impressive ability to tolerate those poisons. And they don’t frequently catch Lyme disease, even though they are often bitten by ticks. In fact, they typically eat the ticks before they have a chance to infect them. Opossums also have superpowers against snakes. They have partial or total immunity to the venom produced by rattlesnakes, cottonmouths, and other pit vipers. In order to develop a low-cost rattlesnake antivenom, scientists are recreating the peptide found in opossums. 9. They Provide Free Pest Control Since their diet allows them to indulge on snails, slugs, and beetles, they can be a welcome addition to the garden. They also help clean up sources of pests by eating rotting fruit and vegetables. Opossums also keep rats and cockroaches at bay by competing with them for food. In fact, it’s common for opossums to kill cockroaches and rats if they find them in their territory. 10. They Gravitate Toward Water Opossums tend to gravitate toward living in areas with reliable water access, and they are actually quite proficient swimmers. Although they spend most of their time on land or in trees, opossums sometimes head to the water to escape predators. They can swim both underwater and along the surface, using their limbs and tail to move themselves through the water. View Article Sources Pérez-Hernandez, R., et al. “Didelphis virginiana.” The IUCN Red List of Threatened Species, 2016, pg. e.T40502A22176259., doi:10.2305/IUCN.UK.2016-1.RLTS.T40502A22176259.en Krause, William J., and Winifred A. Krause. The Opossum: Its Amazing Story. e-book, William Krause, 2004. “Give Opossums a Break.” The National Wildlife Federation. 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