Last night, at dusk, we had a surprise visitor to my mom’s feeders. Opossums live in the woods around my parents’ and make regular appearances at the front porch to nibble on the dry cat food left out for the stray. They’ll occasionally stop at the seed spread out on the driveway on their way through, but I’m not sure I’ve seen them under the feeders before (of course, I’m not there very often these days, and Mom may have observed behaviour I haven’t). They’re generally nocturnal, so to have one out in the daylight is unusual. It may be that all this extended snow cover has made it rather hungry and prepared to resort to abnormal behaviours to get food.
It was chowing down on what I took to be suet droppings from the suet feeder overhead, but which could also be seeds spilled from the sunflower seed feeder. The birds that visit the suet feeder would be likely to dislodge pieces of suet as they’re pecking at it, though, which is why I presumed that. They have diets similar to raccoons, being omnivorous and opportunistic in nature, eating small rodents, amphibians, insects, eggs, various fruits such as apples, and will even scavenge roadkill (which often results in them becoming roadkill themselves). They have 50 teeth, which is the most of any North American mammal.
Formally called Virginia Opossum, but colloquially often referred to simply as “possum”, they’re the only marsupial in North America. Like the well-known kangaroos of the Australian outback, they carry their young in a pouch on their belly for nearly two months (incidentally, the opossums of Australia are a totally different scientific order, but bear the same name for their similarity to the North American animal – the name “opossum” comes from an Algonquian word, “apasum”, meaning white animal). The pouch faces backwards in possums, because when the young are born (after only 12-13 days gestation! They’re so small when born that the whole litter will fit into a teaspoon), they must pull themselves, grabbing the mother’s fur, into the mother’s pouch and find a nipple to feed from. They remain attached there for several weeks. Opossums have thirteen nipples, arranged with twelve in a circle and one in the centre.
Possums have prehensile tails, which they can use to grab branches with when climbing. Their tails are very rat-like in appearance, lacking much hair and having a somewhat scaly appearance. Because the lack of hair on their tail and eartips are not a great winter adaptation, their tailtips will usually freeze in the winter, and it’s extremely unusual to encounter a possum that has survived the winter with its tail intact. You can see this individual has lost the tip from its tail, but some may lose up to half their tail in the winter from frostbite.
As their name implies, they are historically a species of the southern North America, and range through Central into South America. In North America, their range has slowly been spreading north as the expansion of human settlement has allowed them to survive otherwise harsh winters by providing ample food supplies. They’re now found into southern Ontario, northern Minnesota and New York. A disjunct population was introduced to California in 1890 and now occurs along the west coast as far north as Vancouver area.
Possums have extremely dexterous hands, with long, slender fingers, similar to those of raccoons. The pattern of pigment on their hands reminds me of fingerless gloves. Their hands are designed for manipulating food and other objects, and are too delicate to do much digging. As a result, opossums will take over old burrows or tree cavities that are already formed by natural events or other creatures.
Their back feet have opposable “thumbs”, like our hands. You can just see them in this photo, particularly the right hind foot, sticking out at a 90 degree angle. They use these toes for gripping branches which aids in climbing and foraging in trees. Because of this unique feature, possum tracks are very easy to identify.
Like most animals, possums have extremely long whiskers that they use for sensing their environment. They keep these whiskers folded back against their face when not foraging or moving.
Of course, the possum’s most infamous feat is to feign death in the face of danger (the basis of the phrase “playing possum”). Apparently involuntarily prompted by extreme fear, the possum will go into a catatonic state with its eyes open and tongue lolling, and its breathing slowed to nearly undetectable. It even goes so far as to excrete a putrid green fluid from anal glands. It can remain in this state up to four hours in extreme cases. The idea is to discourage predators who hunt live prey, but of course this doesn’t work so well with vehicles, and the defense loses its effectiveness on roads.
A lot of people find opossums to be rather ugly, but I think they’re cute and certainly unusual animals of our landscape, and I’m always pleased to have one visit.