Are opossums good in the garden?

One night last week, I heard my dog barking his head off in the backyard.

That sound, I’ve come to recognize, means some kind of critter, perhaps an opossum or raccoon, has found its way into the fenced area near our house and triggered the alarm on our fluffy dog Baxter.

As a wildlife-conscious gardener, I’ve followed some of the guidelines for encouraging reptiles, small mammals, bugs and pollinators to visit or dwell in my yard. I never set out to attract a possum. Yet how can I blame one for hiding in my undisturbed branch piles or looking through the leaves and grass for insects? Aside from the barking, is there actually a downside to allowing the little fellow to hang out on our property?

I posed the question to wildlife biologist Ann May, who works for the N.C. Wildlife Resources Commission. She cut straight to the chase.

“Opossums play an important role in the natural ecosystem because they eat dead and rotten things, but they aren’t charismatic animals,” May said.

Part of our world since the days of the dinosaurs, opossums are generalists and so can live in many locations and eat different things. Their skill in exploring backyard garbage cans and raiding bird feeders stems from the opposable digits on their paws that make them adept at opening lids on containers.

According to the N.C. Wildlife Resources Commission website, English explorer John Smith in 1610 described the Virginia opossum (scientific name Didelphis virginiana, North America’s only native marsupial) as having “the head of a pig, a tail of a rat, and the size of a cat.”

Opossums may have up to 15 young at a time, but more typical litters are four to seven pups, which remain in the mom’s pouch attached to nipples for the first 48 days of life, then they venture out slowly over time to prepare for independence. Their average lifespan is only three to four years in the wild. As adults, they live alone, staking out a territory involving food supplies they feel obligated to defend, which may include grapevines and other fruit and vegetable plants in your garden. Near chicken coops, like the one in our neighbor’s backyard, are another place opossums like to hang out.

May says it is advisable to stay away from opossums – or any other wild animal – you may find in your garden.

“Respect that these are wild animals and don’t encourage them to get too used to humans,” May said. “These aren’t aggressive animals by nature, but if one gets used to an area and then is startled by a pet or human, they may scratch or bite.”

So keep your birdseed, pet food and outdoor trash cans on lockdown to minimize the chances of a close encounter. Although opossums actually do “play possum” — they actually faint once they have been captured — they may first put up a fight in the confrontation that involves this neat trick.

Here’s how the N.C. Wildlife Commission website describes it: “An opossum will first face the predator with its mouth open and will hiss or growl. If it grabs and shakes the opossum, it will feign death while defecating and emitting a foul-smelling greenish substance from its anal glands. This behavior frequently causes the predator to release the opossum and leave it alone.”

No doubt.

While you may not be tempted to confront a defensive opossum, there are other precautions that May advises for gardeners who are or may be sharing their property with wildlife, including removing bird feeders or at least keeping a tight lid on your seed, as well as securing any pet food and outdoor garbage cans and other refuse. Even a pile of discarded oyster shells became home for a mama possum and her litter near a neighbor’s home in Raleigh.

If the problem is extreme, commercial repellents are available that are designed to ward away opossums and other such visitors. A list of homemade remedies circulated by various pest control companies include placing mothballs in the garden and spraying or setting cans of ammonia in strategic locations.

For gardeners concerned about self protection, May urges them to wear gloves when working in the dirt.

“Any kind of wild animal may leave feces in your yard, and it is possible that feces carries diseases,” she said. “If you get it on your hands and then go in for a cup of coffee or to eat, you run the risk of infection.”

Among diseases known to transfer from wild animal feces to humans are tuberculosis, toxoplasmosis and trichomoniasis, as well as roundworm eggs, fleas and other parasites.

Rabies is not transferred through feces, but animals such as racoons, skunks and, less so, opossums, may carry the disease, which is why Baxter and other pets should be restrained from tangling with any backyard visitors.

Finally, I asked May about a Wildlife Resources Commission project I’d noticed involving armadillos. I have yet to spot an armadillo anywhere near Raleigh, but the commission has been monitoring their appearance in the state since 2008. Confirmed sightings have been reported in the western and southern areas of the state and as far east as Bladen County.

Approximately 15 percent of armadillos carry leprosy, also known as Hanson’s disease, a fact I learned while viewing a July 2015 CNN report on a small uptick in leprosy cases in Florida – from an average of about 10 per year to nine in the first six months of 2015.

The U.S. Center for Disease Control records about 100 cases per year of leprosy, a skin and nerve disease, annually, most of which are transmitted through coughing and sneezing. However, five percent of cases of the bacteria-based infection are traced to other sources, which include contact with armadillos.

The CDC therefore urges people not to touch armadillos, including souvenirs made from armadillo skins, which are popular in some Western states.

May urges anyone who sees an armadillo in North Carolina to note the location and the animal’s activity, take a photo if possible, and then call the commission at 919-707-0050 to report the sighting.

And don’t forget to pull on your gloves before heading out the door to garden where wildlife may have roamed.

This story was originally published January 29, 2016 at 3:01 AM with the headline "Are opossums good in the garden?."