The problem with being an opossum, taxi driver Christopher Lee once told me, is that “one strongly resembles an enormous rat.”
Lee spotted his first Maine opossum in 1997, while driving on Portland's Capisic Street one July night. He recognized the cat-sized creature immediately — the hairless tail half as long as its body was a dead giveaway. But his passenger exclaimed, “Wow! What a big rat,” and urged him to run over it.
Lee refused, though he wasn't surprised by his passenger’s reaction. “Nobody likes anything with a rat tail,” Lee said. “If squirrels had rat tails, nobody would like them, either.”
Not many people are worrying about opossums, but last winter and this one may be taking a toll on them, along with Maine’s other small mammals, says Keel Kemper, the regional wildlife biologist in Sidney.
“You don't hear much about it, because everyone focuses on deer etc, but the guys who do nuisance wildlife work for a living will surely tell you,” Kemper write in an email. “The number of skunks and raccoon complaints this spring and summer was down dramatically. I know guys who may trap 100 skunks per year from inappropriate locations and this year they maybe trapped less than a dozen. They attribute it to winter mortality. These very issues could easily beat back the range of opossum and limit the few that are here.”
Opossums were not found north of Pennsylvania when European colonists first arrived in North America. But one opossum was captured in Ontario in 1858, and in the early 1900s they were first spotted in New England. They seem to have been inching northward ever since.
An Associated Press story on Jan. 25, 1957, reported: “First Opossum Found in New Hampshire” and Gene Letourneau, who covered the Maine outdoors for more than 60 years, reported sightings of opossums in central Maine on Aug. 14, 1958. Letourneau also showed readers what was thought to be the first opossum photographed in Maine (in Ogunquit) on April 10, 1960. But it wasn't until around the late 1970s that opossums became numerous enough to start turning up in traps in southern Maine. Since then they’ve become fairly common in southern Maine and along the coast.
“Trends are always tough, especially when you’re dealing with a species literally on the very edge of its range,” Kemper said. “Range boundaries tend to ebb and flow, so we may have many opossums one year and not so many the next.” In much of Maine, opossums are still a novelty.
You’re most likely to spot them as road kill, but there’s at least one heartening story about a pregnant opossum that was saved by a passing driver and the care of the York Center for Wildlife .
Ugly as it is, the opossum has claimed a colorful spot in our thoughts and speech. We say someone is “grinning like a possum,” because opossums have the most teeth (50) of any North American land mammal. They’re also known for their passive resistance. Feigning death in the face of overwhelming odds — “playing possum” — is a tactic that’s probably cost many opossums their lives. They're eaten by everything from owls to coyotes to people, some of whom report they're tasty but “greasy. Yet somehow opossums have managed to survive for eons.
“Opossums are pretty much prehistoric,” Phil Bozenhard, a retired wildlife biologist told me. “They're a step back (in evolution).”
Scientists theorize marsupials originated on a large continent that later split to become the present-day Australia, South America and Antarctica. In Australia, the lack of predators preserved many species of marsupials, but opossums are the only marsupials (mammals that raise their young in pouches) in the Americas only the opossum was hardy and versatile enough to survive. Some took to the trees, like murine opossums, which resemble mice. Another type, the yapok, became the only marsupial to develop webbed feet, which allow it to live in water. And there really are rat opossums, which live in western South America and eat insects and other invertebrates.
But only the Virginia opossum has made it north of the Rio Grande River, and its progress has been limited by cold weather and aided by people. Maine wildlife rehabilitators have been brought opossums that are badly frostbitten, some so severely that they've lost their tails or claws. But opossums also benefit from bird feeders, garbage, pet food and buildings with crawl spaces where they can weather the winter. Opossums rarely become a nuisance because, since they’re nocturnal creatures, they’re seldom seen.
I’m always interested in how far north they’ve travelled in Maine and so is Kemper.
“So far I have confirmed opossum in Waterville but I would not be overly surprised to find or hear of them in Bangor,” Kemper said. “Short of a semi truck ride to Houlton, I would not expect them to occur in the County.”