Klemek & Minnesota Outdoors: Flying squirrels really don’t fly - they glide

Blane Klemek
Crookston Times

    Although not suited to everyone’s taste for items making up the perfect backyard bird feeding station, I often hang a skinned deer carcass from a tree. These carcasses are from deer I have hunted, which in turn serve to feed a multitude of suet loving birds with long-lasting, protein-rich food sources.

    One night a couple of months ago as I stepped out on the deck for breath of fresh winter air, outside lights on, I noticed something move on the tree where the deer carcass was hanging. With my attention now turned to the area, I soon learned what it was—a flying squirrel. For several minutes I watched the fury little nighttime squirrel feeding on fat from the carcass. What a treat it was to observe one of these tiny squirrels going about its activities.

    Two species of flying squirrels inhabit Minnesota: one, like my furry little friend filling his belly with venison, is the northern flying squirrel.  The other species is the southern flying squirrel. Both mammals are rodents and are non-hibernating tree squirrels.

    Northern flying squirrels have the most extensive range in Minnesota and North America.  They occur throughout central and northern Minnesota in a variety of forest types.  The North American range of southern flying squirrels is mostly east of the Mississippi River, which includes central and southeastern Minnesota.  Both species prefer habitats of mature, broad-leaved forests.

    Northern flying squirrels are larger than their southern relatives—about twelve inches versus nine inches long.  Both species are about the size of chipmunks. The color of their fur coats is similar for both squirrels, ranging from brownish to brownish gray.  Their belly fur is whitish.  

    The tails of flying squirrels, a distinguishing feature, are long, flat and fluffy.  Such tails act as rudders as they glide through the air.  Their eyes are very large and ringed with black fur.  But the flying squirrels’ most unique feature is the folds of skin between their legs.  This furred membrane, called a patagium, stretches between the front and back limbs and is attached to the ankles and wrists.

    Flying squirrels are especially active at night, but can also be observed at dusk and dawn.  They feed on a variety of seeds, grains, fruits, berries, buds, and nuts.  Their diet also includes fungi, mushrooms, insects, bird eggs, and even young birds and carrion. The inquisitive and docile acting squirrels are common nighttime visitors to backyard birdfeeders.  Most people don’t mind watching bands of flying squirrels raiding their feeders in the dark of night.  

    Contrary to some beliefs, flying squirrels really don’t fly—they glide.  The whole sequence, from launch to landing, is really nothing more than a controlled freefall.  By launching themselves from the upper parts of trees and other structures, flying squirrels glide through the air to reach the lower parts of nearby targets.

    This amazing descent is accomplished by extending their limbs to expose the “patagium” stretched between their feet and by holding their tail straight behind them. Flying squirrels are capable of maneuvering and steering their bodies in order to land where they want to. Resembling a flying magic carpet or kite, a flying squirrel’s glide can extend 100 feet or more.

    Nests are usually constructed inside naturally occurring tree cavities and woodpecker holes.  But, as I’ve learned over the years, bluebird houses, and even wood duck houses, are favorite nest sites too.  During the winter, several flying squirrels will often den together to stay warm.  Litters of up to seven, usually two to four, pups or kits are born blind and hairless in the spring.   

    Indeed, if you feed birds and are fortunate to live where flying squirrels inhabit, which is probably the case whether you know it or not, check your birdfeeders at night now and then.  If you discover that flying squirrels are present, you can do like what I did and arrange lighting toward your feeders in order to better observe these special species of squirrels.  We’re lucky here in Minnesota that both tree and ground squirrels abound. And some, like flying squirrels, are abundant, too, but mostly at night as we get out and enjoy the great outdoors.