Fairydiddles

It’s dark, it’s cold, and the wind is howling through the trees like a choir of banshees. I’m standing with feet slowly going numb, on the back porch of the Long Branch Nature Center in deepest darkest suburban Arlington, Virginia, waiting on the appearance of wood sprites.

Although they are real creatures, as serious about making a living as any Internet tycoon, fairydiddles or flying squirrels have contributed to enough ghost lore in North America to qualify as semi-mythical. Readily entering houses, flying squirrels get into small spaces in search of food. Attics are a favorite haunt. Stories about spinning wheels turning without human assistance may be laid at the furry feet of these wee beasties who like nothing better than an exercise wheel, no matter what the original purpose.

About a third the size of their more familiar cousins, flying squirrels come out about an hour after dusk. They are actually more common in the mid Atlantic than grey squirrels, their bigger cousins. Being small, quick, and above all, nocturnal, they are usually seen, if at all, as a pale flash in the night woods or a dark shape against a full moon. Of the fifteen or so species world-wide (mostly in Asia including the four-foot long woolly flying squirrel), we have two; the southern and northern species. Northern flying squirrels are found in the mid Atlantic in the mountains in pockets of boreal forest left over from the glacial days and stranded on mountain tops like Dolly Sods in West Virginia. Their southern kin are everywhere else.



Flying squirrels rely mostly on nuts as winter food. Since they have small mouths and can’t stuff their cheeks like chipmunks; they must gnaw a hole in the nut to be able to grasp it while they scamper and fly. They also have a unique way of dining. Grey squirrels chew an acorn to bits while eating it; you find a pile of shell fragments. Mice leave a jagged edge as they gnaw through the shell, bisecting it like you would a soft-boiled egg. Flying squirrels will chew a round hole in the nut and extract the meat. The nut shell looks like an olive minus the pimento. While they will eat peanuts (everything is attracted to peanuts from mice to grizzly bears), flying squirrels prefer hickory nuts and hazelnuts are at the top of their culinary chart. Food not eaten on the spot is cached in scatter hordes, a few nuts here a few there, in hidden locations throughout the forest canopy. In spring and summer, flying squirrels become ravenous carnivores, feeding on large insects like grasshoppers, katydids, and moth larvae and adults. They will eat bird eggs and nestlings and the young of other squirrels, including those of their own species.

Until the babies are about three weeks old, their mothers cannot tell them from other baby flying squirrels and will care for and adopt anything cute and cuddly that they happen across. Researchers at VA Tech discovered this when a family of flying squirrels moved out of their damaged tree hole nest. The mother took a baby in her mouth and sailed off to new digs and came back for the next. The researchers would add a new baby to the nest every time she left. Twenty or so babies later, they came to the conclusion that: a) flying squirrels can’t tell their own babies from others, and b) flying squirrels can’t count.

Not only are they lacking in mathematical skills, flying squirrels can’t really fly, either. Among the mammals, only bats are capable of true powered, flap-your-wings to get where you are going flight. Flying squirrels, however, are champion gliders. They possess a specialized flap of skin, the patagium, stretching from the front legs to the back legs. This flap gives them an enormous (relative to their size) area to act as an air foil. The furry tail spreads out flat for additional airfoil area. Contrary to belief, the tail is not a rudder—flying squirrels steer by swooping and banking, much like a paper airplane. When they get to the target, they use their momentum to scoot 180 degrees to the opposite side of the tree trunk in a singe movement. This disappearing act is an anti-owl maneuver--owls are the flying squirrels’ major predator but owls must learn to counter the flip-around-the-trunk move by flying past and snatching backwards with their talons as they sweep by. In some areas where the owls have figured this move out, flying squirrels numbers are kept low. In areas with less adept owls, flying squirrel populations boom.

Flying squirrels will sometimes crash-land. They have extremely long whiskers which they point forward as they glide. The whiskers act as an early warning system; if they touch a surface first, indicating an incipient crash, the squirrel is quick enough to adjust and land more or less correctly. Flying squirrels are very noisy little beasts; they chatter constantly, even in the air. These vocalizations are so high-pitched as to be inaudible to adult people, and it was once thought that they served as a form of echo location. Up stepped our friends from VA Tech once again with another experiment. They set up a maze and let flying squirrels traverse it in low light conditions. With their outsized eyes exquisitely adapted to dim light, the squirrels had no problems navigating the maze to the reward (you guessed it, peanut butter). When the lights were fully off, leaving the maze in complete darkness, the squirrels crashed into the walls with happy abandon. The conclusion--flying squirrels don’t echo locate (at least not well) although they are very chatty.

A pale flash in the dark and the scrabbling of small claws on bark announces the arrival to the bait of the first customer of the evening. As if by magic, a small face appears on top of the squirrel roosting box, grabs a peanut, and vanishes. The flying squirrel gnaws a small hole in the nut shell to carry it away. I can hear rapid munching noises from the other side of the trunk, moving higher up into the canopy. Flying squirrels need at least a foot of elevation for every two feet they soar. The squirrel climbs to the top of the old oak and launches; we follow the flight with the beams of our flashlights, watching it hit the air brakes and flip upwards for landing on a hickory down the valley. A flip of the tail and the fairydiddle is on the far side of the tree and gone to hide the peanut for future meals.