If you have spent time outdoors in the Upper Delaware River region, it’s very likely that you have seen many gray squirrels, as well as some red, black and fox squirrels. It is less likely that you have encountered flying squirrels, due to the fact that they are nocturnal and primarily arboreal, living most of their lives unobserved in the forest canopy.

The name is a bit of a misnomer, as flying squirrels don’t actually fly in the traditional sense. It would be more accurate to call them gliders, since they soar in a downward direction from tree to tree, typically in ranges of 20 to 65 feet, though greater distances have been recorded, according to the Pennsylvania Game Commission. 

The feature that enables their “flight” is the loose flap of skin (patagium) stretching between the front and rear legs on both sides of their bodies. When the limbs are extended, the furry membrane becomes taut as the small squirrel leaps into the air and “takes flight.”

Squirrels are members of the family Sciuridae, which includes small- to medium-size rodents. Our local squirrel species do not interbreed. Flying squirrels typically range in length from eight to 10 inches, including a broad, flat 3.5- to five-inch tail, which is used like a rudder when the squirrel is airborne. 

Observed up close, the diminutive flying squirrel is disarmingly adorable, like a plush animal come to life, with large dark eyes—an adaptation for enhanced nocturnal vision—and velvety fur reminiscent of cashmere.