Thursday, March 16, 2017

Opossum Freeloader

Today we had a first, an opossum at our bird feeder.  We have a constant battle of wits with gray squirrels (last count, squirrels-8, Bob-0) and an occasional raccoon grazing the sunflower seed that falls on the deck.  Now we have an opossum that has figured out how to get into the suet feeder.

We first saw it last week, waddling along the deck and into the leaf litter below.  I didn't mind cleanup efforts on the deck but I was startled to see it clinging awkwardly to the tree while using its claws to dig into the wire lattice holding the last block of suet of the winter.  After getting some pictures I walked out, expecting to startle it, only to find myself in a stare-down from two feet away.

Up close and personal - two feet from the camera
For a slow moving, passive mammal that evolved as the last of the dinosaurs were going extinct, it is amazing that it is still around.  They look like they were designed by a committee that couldn't decide between a rat and a pig and so combined them.  Their appearance and their defensive hissing hasn't won them many fans, but we find them the most fascinating of mammals.

Climbing a swinging suet feeder didn't work.
They are the only marsupial in the Northern Hemisphere, having crossed the newly formed volcanic Panama land bridge from South America somewhere between 3-10 million years ago.  With only a primitive placenta at birth, the newborn possum must make the trip from the birth canal up the abdomen and into the marsupium (pouch) alive (not all do) and hope there is an open teat.  With up to 20 newborns and only 13 teats, some will likely starve.

Their lifespan is very brief, averaging 2-4 years.  During that time they are total omnivores and it is estimated that they will consume 5,000 ticks that collect on their body in their lifetime.  She is the ultimate single mother, carrying the young in a pouch that can be sealed water tight when she swims while later the young will all cling to her back as she climbs around.

Their defense is rather tenuous, a combination of fierce and harmless hissing and as a last resort "playing possum."  Their lips are drawn back, the teeth are bared, saliva foams drools around the mouth, the eyes close or half-close, and a foul-smelling fluid may be secreted from the anal glands.  This is enough to make many predators think that the animal is sick and therefore inedible.  The opossum isn't "playing" but rather a state of shock where the involuntary response may last minutes to four hours.  This maybe a good reflex when faced by an animal predator.....a car on the highway, not so much.

The opossum is not without its fans.  If the facts above make you one, check out the Opossum Society of the US.  If you are not that "rabid" a fan* just give them wide berth on the highway.  They may not be dead but just "playing possum."

Our opossum's struggles on the tree can be seen in this video.
* Opossums rabies is extremely rare, probably due to their low body temperature.