Maine’s marsupials: Opossums continue to move north

By Aislinn Sarnacki, BDN Staff
Posted Oct. 26, 2012, at 5:02 p.m.

A car struck an opossum near Freeport a few weeks ago. The ratlike animal, about the size of a housecat, died. It wasn’t long before a passerby stopped to get a closer look at the animal, so rarely seen this far north, and quickly realized that the dead opossum had been a mother.

Tiny gray furballs, about 5 inches long, clung to her fur.

Three sister opossums, about 10 weeks old, survived the accident. They had likely been latched to their mother’s back as she foraged for food, as is their habit. Rescued from the side of the road by the compassionate passerby, they were brought to Maine Wildlife Park in Gray, where they will be fed and sheltered.

For centuries, the Virginia opossum, the only marsupial native to North America, has been expanding its range west and north, but it wasn’t until the 1900s that they crawled into northern New England.

“In the last 10-15 years, people started seeing them in southern Maine,” said Lisa Kane, natural science educator for the Maine Department of Inland Fisheries and Wildlife. “They just started moving here, and it’s kind of weird because it’s so cold in Maine.”

Opossums, with naked feet, tails and ears, aren’t built for the cold. In fact, in Maine, if they don’t find proper shelter for the coldest months, they perish. Mainers who find them in the winter will often bring them to the Maine Wildlife Park with partial ears and frostbitten toes.

Nevertheless, since last year’s mild winter, opossums have been spotted farther and farther north.

“I have opossums all over the place [on my property in Poland],” said Maine Wildlife Park gamekeeper Howie Powell. “I have one living under my steps. And I’ve never seen one in Poland until this year.”

“They’ve adapted well to cities and have been found as far north — as far as I know — as Bangor, being hit by cars,” Kane said.

The three orphaned opossums at the Maine Wildlife Park, after two weeks eating and resting in an indoor shelter, are now more than a foot long and appear to be perfectly healthy. In fact, they’ve developed the dramatic attitudes characteristic of their species. They growl when people draw near, opening their long, narrow snouts wide and showing their 52 teeth — more teeth than any other mammal in North America.

“They’re very menacing-looking creatures when they open up their mouths and quote-unquote smile at you,” Kane said. “But they don’t have any reputation for attacking anybody.”

When not snarling, they’re borderline cute, with black beady eyes, fluffy fur and Mickey Mouse ears. Their feet are eerily similar to human hands, with five long, separated toes. And on their hind feet, the first toe is opposable in the exact same way as a human thumb.

“They’re not that bad. They’re all bark,” said assistant gamekeeper Pam Richardson, who has cared for several opossums at the Maine Wildlife Park since she began working there in 2004.

If opossums truly feel in danger, they’ll collapse and “play ’possum.”

To “play ’possum” is an expression that comes from the opossum’s strange habit of feigning death when frightened. It goes limp and rolls on its side, with eyes shut, mouth agape, tongue out, and tail and body curled. It will even shrivel up its large, round, black and white ears.

“They send off this horrible scent of death from a scent gland in the back,” said Richardson.

Opossums can play dead, unmoving, for hours, waiting for the confused predator to leave them alone. And surprisingly, this tactic is effective. It tends to puzzle dogs, foxes and other animals that don’t eat carrion.

Playing dead is only one of the opossum’s many survival skills. The animal is also a skilled climber and an opportunistic eater. In other words, it eats just about anything it can find, from eggs, berries, bugs and snakes to trashed table scraps. And while they don’t exactly hibernate, they do become inactive during cold spells, subsisting on fat stored during autumn.

Their ability to adapt and survival skills may explain why they have survived so long and evolved so little. Opossums date back to the late Cretaceous period, 65-90 million years ago. Fossils from that time show that among the earliest mammals were marsupials resembling the Virginia opossum.

Opossums were around to see the end of the dinosaurs, and as the continents spread apart, they survived to witness the emergence and extinction of grand prehistoric mammals such as the saber-toothed cat, woolly mammoth and giant ground sloth.

One present-day factor that works in their favor is that they aren’t a very appealing game animal.

In Maine, the Virginia opossum may legally be trapped during the statewide trapping season from Oct. 28-Dec. 31. But compared to other fur-bearing mammals, opossums aren’t particularly valuable. At fursource.com, a Virginia opossum pelt costs $25, fairly cheap compared to the $130 beaver pelt, $110 coyote pelt and $120 red fox pelt. And while “possum and taters” is a widely known dish in the south, opossum meat isn’t in high demand.

The opossum we are seeing in Southern Maine, the Virginia opossum, is just one of many opossum species, all of the family Didelphidae. Mainers interested in finding them will likely be more successful searching at night, when these small marsupials leave their nest to feed. Their nests are usually built in hollow tree trunks or abandoned burrows, but in Maine, opossums are often found near people’s homes — in garages, sheds and basements — because they are attracted to the warmth and potential food source.

People typically picture opossums hanging from trees from their prehensile tail (capable of grasping), but this acrobatic feat is usually only performed by young opossums. Adults, being heavier, typically use their tails only as a fifth hand for extra support in climbing, according to the International Wildlife Encyclopedia. They may also use their tails to carry things, such as material for their nest.

A lone adult opossum currently occupies the exhibit at the Maine Wildlife Park, and he currently measures nearly 20 inches long from the tip of his nose to the base of his tail. At two years old, he’s nearing the end of his life. Opossums are short-lived and reproduce rapidly.

The three young opossums that recently joined the park population will remain onsite rehabilitation building during Maine’s harsh winter. Currently, they share the space with a blind grey fox and two orphaned white-tailed deer.

Next spring, the opossum sisters become “ambassadors of their species” in the park’s outdoor opossum exhibit, said park superintendent Curt Johnson.

“They make a poor exhibit animal,” he said. “During the day, they’re very inactive. And we joke around that what the visitors can expect to see is a little patch of hair sticking out of the log because that is what you see every day.”

Perhaps the three youngsters will be a little more rambunctious and even hang from their tails, but all in all, opossums put on a dull show for such an extraordinary animal.

http://bangordailynews.com/2012/10/26/outdoors/maines-marsupials-opossums-continue-to-move-north/ printed on July 25, 2014