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Making Peace with the ’Possum

~Contributed by Mark Branning

 

Making Peace with the ’Possum

“U-G-L-Y, you don’t have any alibi, you’re ugly!” “Just plain disgusting!” “Mean, ugly, pesky!” “Loathsome!” “Shoot it!”  These are just a few examples of common feelings about the lowly opossum. Truth be known, the ‘possum is about as harmless an animal as you can find in nature. We had a Chihuahua named Chico, who was way meaner than any opossum I’ve ever seen, and he slept in our bed . . . but that is another story. The important thing for you to know is that opossums are really quite interesting and helpful to have around.

History

The name, opossum, comes from the Algonquin Indian name, apasum, meaning “white face.” Mythological stories of the opossum appear in Native American and Mayan folklore. Prior to the 1900’s, the Virginia opossum (Didelphis virginianus) was found predominantly in the southeastern United States and Central America. With the expansion of the human population, the opossum followed northward and westward. Escaped pet ‘possums and intentional releases promoted the accelerated expansion of their range. Opossums, like many animals formerly found only in the wild, have adapted well to an urban environment where dense human population brings an abundance of food and shelter for this omnivorous creature.

Opossums are the only North American marsupials. They carry their young first in the uterus, just as other mammals do, and then later in an external pouch called the marsupium, meaning “double womb.” These creatures shared the earth with dinosaurs over 70 million years ago. While dinosaurs are extinct, opossums are still here, relatively unchanged. They must be doing something right! Other well known marsupials are the opossums’ distant cousins, the kangaroo and the koala, of Australia.  

Opossums are very smart, but slow and cautious individuals. Moving slowly does not “excite” predators to chase. The opossum has survived millions of years of evolution by being adaptable and wary.

Food

Opossums eat fruits, snakes (opossums are immune to all types of snake venom, except that of the coral snake), insects, snails, slugs, eggs, mice, rats, fish, frogs, crayfish, and carrion. If for no other reason than pest control, opossums are great to have around! In urban settings, an opossum will eat pet food, bird seed, and garbage; this animal forages constantly because it has no food caches like squirrels, and it carries little stored body fat.

Shelter

Any safe, dry place will work as shelter for an opossum: a crevice, underbrush, or a hollow log; the space under a deck or outbuilding, or the occasional attic, if access is available. (Usually a squirrel or raccoon will do the access work!) Opossums will pad any available shelter with leaves or grass carried in the tail or back paw.

If you have an opossum around today, just be patient; he or she will move on shortly! The animals are nomadic creatures and are not “den” animals; they never stay long in one place. One study showed that a radio-tracked male had moved nineteen times in just a few months. A female with young may stay in one place for longer periods if she is not disturbed and has an adequate sources of food and water. I periodically check several known opossum “hides.” They are rarely used more than a couple of nights in a row by the same animal (sometimes they are shared with a raccoon or two).

Babies (Pups or Joeys)

Opossums breed almost all year long in temperate areas where mild winters have become the norm. They can have as many as twenty-five babies that compete for the thirteen available teats. Almost half of the pups who reach the pouch will die before maturity.

Opossums of all ages are subject to predation by dogs, cats, coyotes, bobcats, hawks, and owls. The younger they are, the more vulnerable they are. We have all seen an opossum killed along roadside. Although the adult may be injured or even killed by a car, if it has babies, many of the babies may be saved by getting them quickly to a rehabilitator. In any setting they very rarely live to see their third year.

Behavior

Opossums are very much like housecats, constantly grooming when not eating or sleeping. They usually rest all day, except when food is scarce; then they may be seen out during the day. These nocturnal animals can travel many miles foraging at night. Although opossums spend all their foraging time on the ground, they are surprisingly strong climbers, often seeking safety from predators (and sometimes even rest) in trees. Contrary to popular belief, opossums do not hang by their tails. The tail is an extra “grasping and balancing” device like an arm or hand. An opossum can’t jump or run; running, for an opossum, is a very fast walk. They also swim quite well. Opossums are true loners, not social at all except during mating. Usually, if one opossum sees another, it will walk the other way, so as not to compete for the available food sources. 

Identification

Opossums are up to 3 feet in length (including the tail) at maturity. They are 6-20 lbs. in weight, depending on availability of food, and have a light grey to white face. Their bodies can be cream to tan, tan to dark brown, or grey to black from neck to rump. The majority of opossums are grey with longer silver “guard hairs” on the entire body. Their prehensile tail is round, off-white and almost hairless. The head is conical-shaped with two round black eyes and a pointy muzzle tipped with a pink nose. Baby opossums are often confused with rats or baby squirrels.  Take a look at these identification clues:

Sounds

Opossums are almost silent. When cornered or attacked, they will rumble, growl and hiss. They will bear their teeth and snap, almost all of which is a hopeful bluff. The young make an expectant “ch-ch-ch” sound when calling for their mother. She responds by clicking her tongue to the top of her mouth once or twice in answer to say, “I am here.”  

Playing ‛Possum

When they feel threatened, opossums will slowly walk away, crawl under something, or climb a tree if available. However, when caught in the open or attacked, if all the other bluffs have failed, they will “play ‘possum.” They will fall down, stick their tongues out, drool and foam, excrete urine and droppings, and emit a viscous green fluid from a sac under their tail. By all appearances, they are dead. Most predators won’t eat anything that smells like spoiled meat.

This “act” is a true seizure. The animal has little control over when it begins or ends. Poking and prodding will produce little movement.  This can last for a few minutes to several hours. The ears will usually move first. This is an effort to determine if the danger is gone.  After the animal revives, any other danger stimulus can send it right back into a comatose state. Do not assume an animal in such a state is dead. Please don’t put it in a plastic bag, trash can or bury it; it may still be alive!

Avoiding Conflict

Opossums are not dangerous as long as they are not cornered and their interaction with other animals and humans is kept to a minimum. They are beneficial to eliminate rodents, snakes, insects and carrion, and they provide a VITAL “grounds-keeping” function in most urban environments. When awake, they forage constantly, cleaning up food that might attract less-desirable mice and rats. They are gentle, and remarkably placid, even around people and pets. But, they WILL protect themselves and their young if necessary. You may have provided, perhaps by accident, the food and shelter they seek. The best way to prevent conflicts is to modify the environment.

Food Source Modification

Don’t purposely or inadvertently feed opossums or any wildlife. This will inevitably lead to undesirable situations. Feeding wildlife causes the animals to lose their fear of other animals and humans. When concentrated into a small feeding area, disease and parasites can be spread to people, pets and other wildlife that would otherwise never have come into contact with each other. Feeding also puts your neighbors and their pets at risk due to the wildlife’s loss of fear. Feeding these animals is not an act of kindness.

Keep pet food inside, filling bird feeders with what will be consumed that day only (no bird food left out at night).

Keep garbage cans tightly closed. Use bungee cords and cinder blocks, or purchase cans with latches. Put garbage out for pickup in the MORNING, after the opossums have gone to bed.

Keep pets inside at night. City ordinances may vary, but leash laws apply to ALL pets.

Secure compost piles. Animal-secure compost bins are available commercially. Most city ordinances prohibit food stuffs and grease in compost piles for a reason.

Clean outdoor barbecue grills and grease catch cans.

Habitat Modification

Secure under deck, house eaves and chimney access points with a sturdy metal mesh wire.

Use commercially available chimney caps so that a fire hazard is not created. (Take care not to accidentally trap any animals inside while doing this.)

Trim tree limbs to prevent roof access.

Trapping

Trapping and relocating animals several miles away may seem like an acceptable resolution to a wildlife conflict, but it actually creates a multitude of problems. Relocated animals are released in an unfamiliar environment with unknown predators, unknown food and water sources, and unknown shelter. Studies give less than a 50% chance of survival to relocated animals. In addition, the space in the ecosystem vacated by the trapped and relocated animal will quickly be filled by another opossum or maybe an even less-desirable animal.

Health Concerns

Although the opossum, like any other animal, may carry diseases of concern to humans, their actual role in transmission of diseases is not certain. Handling any animal, dead or alive, requires gloves and a thorough hand washing afterwards. The incidence of feared diseases like rabies, although there have been known cases in opossums, is negligible. Testing of wild populations has shown no indication of a recurring presence of rabies; in fact, it is EXTREMELY rare for an opossum to contract this disease. The most often-cited theory is that because of the opossum’s unique physiology (pre-mammal) and lower body temperature, the virus does not find a welcome host in an opossum’s body chemistry. Opossums are remarkably resistant to many common animal diseases, including distemper. All wounds or scratches you might incur, of course, should be thoroughly cleaned immediately, and attended to by a physician.

Conclusion

Although by most standards he is not a pretty fellow, our  much-maligned marsupial, the Virginia opossum, should be viewed as the great “groundskeeper.”  Silently and without cost, he fulfills his role in the natural world, tending to it diligently and without fail.  When left alone, the opossum does not attack pets or other wildlife; he does not chew your telephone or electric wires, spread disease, dig up your flower bulbs or turn over your trash cans. On the contrary, the opossum does a great service in insect, venomous snake, and rodent control. He takes as his pay only what he eats, and maybe a dry place to sleep. The ‘possum tolerates our pets, our cars, prodding sticks, rocks and brooms. “Attacks” by opossums are simply non-existent. When he gets too close, or accidentally moves into your attic space, he can be easily convinced to move along. If you are lucky enough to have one of these guys come around, you can rest assured he is cleaning up what he can, and will soon move along to help someone else.

 

Additional Information on Opossums and Related Topics: