Eeeeeyaaaaaa! Yaaaaaaa! Betty, come quick! Fido’s got a dead rat on the porch! It’s huuuuge!”
“Oh, for heaven’s sake, Frank, calm down. Get down from that chair. That’s not even a rat, it’s a … Uh, wait a minute, honey. Um. That’s a … um … What the heck is that thing?”
These things aren’t complete pushovers, but if faced with a truly formidable opponent, like your Labrador, they have a curious habit of “playing dead” or “playin’ ’possum”. It’s a masterful act, but apparently not really under their mindful control. More like fainting, or a “case of the vapors” and they don’t come to for a while.
It’s hard to imagine playing dead being a good evolutionary decision when you’re dealing with a predator, since that’s what the meat-eater has in mind in the first place. But they also produce some convincingly hideous crab-bait-smelling drool from both ends, so maybe that’s the trick.
About the size of a large house cat, opossums really do look a lot like colossal rats, complete with pointy snout, naked pink ears, patchy fur and scaly tail. But they’re not rodents; not even close. In fact they share less DNA with rats than you do. Males, at about 3-12 pounds are larger than the 2-6 pound females. They’re up to around 3 feet long, with that ratty tail accounting for about half of that.
Well, there’s someone out there for everyone and opossum mating season lasts from about January to July. Since they don’t have a placenta for protection, the babies get kicked out by the mother’s immune system pretty early.
The very tiny young (maybe a little bigger than a pencil eraser) are born after only 12-13 days of gestation and spend their first 50-60 days affixed to a nipple in the mother’s pouch. It’s kind of like a uterus, but outdoors and with some hair and grit.
Later, the young sometimes endearingly ride around on their mother’s backs, but by about 100 days, she’s sick of them and the maternal bond evaporates. Adult opossums prefer their own company and rarely live more than about 18 solitary months. The oldest known opossum was only 3 years old.
Overall, they seem sort of ill-equipped, but marsupials (mammals with this pouch thing) have been around since before the dinosaurs died out and there still are more than 300 different species, mostly in South America and in and around Australia.
The somewhat revolting Virginia opossum is the only marsupial native to North America and is found from Central America on up through the eastern US into southern Ontario. They do pretty well around people, so they’ve been expanding their range northward right along with suburbia and hobby farms.
Somebody thought it’d be a good idea to introduce them to the West and now a population extends up along the coast into British Columbia. Although maybe not so much now that we’re living in the Dorito Age, they used to be hunted for food over a lot of their range (As in “Hey Jethro! Let’s get Granny to whomp up some ’possum and grits! Mmm-mmm!” Remember that from “The Beverly Hillbillies”?).
Their fur is pretty meager in the south, but approaches luxurious in the northern part of their range, but I don’t think opossum jackets ever took off. Northern ’possums often have frost-damaged ears and tails, so maybe their range expansion is nearing its limit. But with climate change, who knows?
Kind of like humans, opossums are opportunistic scavengers, eating birds, eggs, snails, snakes, insects, earthworms, small mammals, carrion, fruit and garbage. If you feed your dog or cat outdoors in opossum country, your house is on their shopping route. They often are hit by cars while foraging for roadkill.
When I worked for the railroad, we’d sometimes see them walking calmly down the rail, hand over hand, or later after the train went by, half a ’possum on each side. Incredibly, some populations apparently have evolved immunity to local varieties of snake venom. You just can’t help but admire them.
Despite having a pretty small brain case, they are generally smarter than dogs in trials, apparently approaching pigs in intelligence. We haven’t had them here on the North Peninsula yet, but I’m pretty sure I saw one of these living fossils roadkilled on the shoulder over there by Discovery Bay last week, so … Wait a minute … What’s that on the porch?
Tom Butler has a degree in zoology from the University of Washington and is a lifelong student of nature. He lives in Port Angeles and can be reached at email@example.com.