Recently the temperature reached 60 degrees, so I headed outside and checked some of my nest boxes. I really didn’t expect to find any active nests just yet, but thought some bluebirds, chickadees or Carolina wrens might have begun gathering nesting material.
No such luck, but in another week nesting will surely have begun.
The contents of one box, however, quickened my pulse. Located on the edge of a woodlot, finely chewed plant material surrounded by an envelope of large intact leaves jammed the box. I gently poked the nest until I saw some movement. Suddenly two big black eyes stared back at me. It was a flying squirrel. After we checked each other out for a few seconds, she jumped from the box and sailed to the base of a nearby tree. She instantly scurried to the far side of the trunk to stay out of sight.
We played hide-and-seek while I tried to get a better look at her. But each time I peeked around the trunk, she managed to keep the trunk between her and me. Finally, after several minutes, she leapt onto a larger tree trunk, and I got a chance to admire her.
Back at the box, I found four naked and helpless pups. I estimated them to be three or four days old. Given the flying squirrel’s 40-day gestation period, this female had bred in early to mid February.
At about four weeks of age, the pups will be fully furred. At seven weeks, they will be adult-sized — ten inches long including a flat four-inch tail and about three ounces — and ready to leave the nest. The first brood stays with mom until she bears a second litter in July or August.
Seldom seen squirrels
Southern flying squirrels (Glaucomys volans) inhabit most deciduous and mixed deciduous/coniferous woods east of the Great Plains and are quite common. If a woodlot has oaks, beeches, hickories, and/or walnut trees, it is sure to have flying squirrels.
Because flying squirrels are strictly nocturnal, they’re seldom seen. An evening in any woodlot, especially one dominated by nut trees, is one way to remedy this. You might hear the sound of teeth gnawing nuts overhead. Or perhaps you’ll catch flashes of white gliding from tree to tree. This is best done on a moonlit night.
As a flying squirrel twists and turns through the forest’s obstacle course of outstretched branches, its white belly stands out in the moonlight. When it lands, note how it disappears to the back of the tree, a habit that no doubt pays off when it crosses paths with a hungry owl.
Varied diet
A flying squirrel’s diet is as varied as the seasons. In February, a flying squirrel might take peanuts, corn, or sunflower seeds from a bird feeder, eat swollen buds, or slice into the bark of a sugar maple and lap up the sap that flows. In May, it switches to insects and occasionally raids bird nests for a meal of fresh eggs or nestlings. In August, mushrooms, fruits, berries, and mice are abundant and irresistible. And in October, flying squirrels gather and store bushels of acorns, beechnuts, walnuts, and hickory nuts to get them through the coming winter.
Fairy diddles, as flying squirrels are sometimes called, eat whatever the forest provides. (In some parts, red squirrels are also called fairy diddles.)
Misnomer
By day, flying squirrels sleep in den trees or nest boxes, often in groups of four to 12 individuals during the winter. Flying squirrels do not hibernate; they huddle together in small groups to stay warm.
One final note: flying squirrels do not fly. They glide. Courtesy of a flap of skin that runs from wrist to ankle on each side of the body, they sail from tree to tree.Upon takeoff, this skin balloons and permits a controlled glide. The flat tail serves as a rudder to guide the “flight.” Most flights are short, 30 to 40 feet, but biologists have observed trips as long as 300 feet.
