When you consider a busy city like Washington, DC, you might not think about exotic wildlife encounters. But the DC-area is home to a fascinating animal: the Southern Flying Squirrel. Many people don’t realize that they may be living with flying squirrels right in their backyards. In fact, flying squirrels are the most common squirrel in North America .
American and Asian Cousins
North America is home to two major species of flying squirrel. The two primary flying squirrel species found in the United States are the Southern Flying Squirrel, Glaucomys volans, and the Northern Flying Squirrel, Glaucomys sabrinus. As you can see from the maps below, the two species of North American squirrel have vast ranges in which they live.
Left: Range Map of Glaucomys volans, the Southern Flying Squirrel . Right: Range Map of Glaucomys sabrinus, the Northern Flying Squirrel . Cassola, F.
Flying squirrels aren’t just found in North America, however. In fact, there are an abundance of flying squirrel species worldwide. Some of the largest include the Indian Giant Flying Squirrel and the Red Giant Flying Squirrel. These squirrels can grow up to 43cm long with a 50 cm tail. That’s almost as large as a house cat! They are widely distributed throughout Asia and have been found in China, India, Laos, Myanmar, Sri Lanka, Thailand and Vietnam .
According to Rachel Tolman from the Department of Parks and Recreation in Arlington, Virginia, watching bird feeders at night is one of the best ways to find out if you share a habitat with flying squirrels. As legend has it, that is how the naturalists at the Longbranch Nature Center in Arlington, Virginia, found out they were home to flying squirrels years ago. Unlike their cousin, the grey squirrel that we see during the day, the flying squirrel is nocturnal, or active at night. Because the flying squirrel is mostly active at night, it can be difficult to spot. But even if you do not see them, they still might be living in your backyard. In fact, in Northern Virgini,a only a few miles from the Nation’s Capital in Washington, DC, the southern flying squirrel outnumbers the common grey squirrel .
Flying v. Gliding
No matter where they are found, or how large (or small) they are, despite being called flying squirrels, they don’t truly fly. Rather, they travel from tree to tree by gliding. What is the difference between gliding and flying? We asked Keith Yoerg, the great great grandnephew of Orville and Wilbur Wright or, the Wright brothers. Yoerg’s explained to us the difference between gliding and flying. Essentially, the difference between an animal that flies and an animal that glides, is thrust. Thrust is a type of push that provides the forward motion needed for animals (and airplanes) to get off the ground. Propulsion is the action of driving or pushing forward consistently. Birds flap their wings and jump to propel themselves forward. Gliding usually begins with a thrust, but lacks propulsion needed to sustain flight. To learn more about how things fly, visit the National Air and Space Museum’s Forces of Flight.
Southern Flying Squirrel. Smithsonian Center for Learning and Digital Access
How Squirrels Glide
Flying squirrels do not flap their wings for continuous propulsion, like birds. Rather, they leap from a tree before they spread out their body and catch air to slow their decent. Flying squirrels use a special flap of skin called, the patagium, that stretches from their forelimbs to their hind limbs to create air resistance and slow their descent, much like a parachute. When a flying squirrel leaps from a tree, both Earth’s gravity and air resistance (a type of frictional force) act on the squirrel’s mass. Earth’s gravity pulls the squirrel towards Earth. Air resistance works in the opposite direction to slow it down. The flying squirrel uses the shape of its body to increase air resistance by opening its limbs and spreading its patagium.
How do these animals steer themselves?
Flying squirrels use their tails to steer themselves mid-glide. According to Dr. Brian Arbogast at the University of North Carolina – Wilmington, flying squirrels are so adept at steering mid-glide that they have been seen turning almost 180-degrees during their glide. Flying squirrels’ tails act as a rudder on the back of a plane. The same innovation was used by the Wright brothers in 1902, and they learned how to make the rudder movable to control yaw. In the picture below, the rudder is visible at the back of the model of the 1911 Wright brothers’ glider.
Model of the 1911 Wright brothers' glider. National Air and Space Museum
Use what you’ve learned about flying squirrels and things that glide to design and build your own glider at home. Follow the link here for an activity you can do at home today.
 Miller, M. (December, 2014) Urban Wild: Flying Squirrels of the Beltway. Cool Green Science. https://blog.nature.org/science/2014/12/17/urban-wild-flying-squirrels-beltway-dc-city-wildlife/.
 Cassola, F. 2016. Glaucomys volans (errata version published in 2017). The IUCN Red List of Threatened Species 2016: e.T9240A115091392. https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T9240A2225717.... Downloaded on 04 June 2020.
 Cassola, F. 2016. Glaucomys sabrinus. The IUCN Red List of Threatened Species 2016: e.T39553A22256914. https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T39553A222569.... Downloaded on 04 June 2020.
 The Smithsonian Institution, National Air and Space Museum. June, 2020. The Wright Brothers: The invention of an aerial age. Image downloaded June 4, 2020 from https://airandspace.si.edu/multimedia-gallery/5809hjpg?id=5809.
 Bishop, K.L., (2006) The relationship between 3-D kinematics and gliding performance in the southern flying squirrel, Glaucomys volans. The Journal of Experimental Biology, 209: 689-701. https://jeb.biologists.org/content/209/4/689
 Arbogast, B. S., Schumacher, K. I., Kerhoulas, N. J., Bidlack, A. L., Cook, J. A., & Kenagy, G. J. (2017). Genetic data reveal a cryptic species of New World flying squirrel: Glaucomys oregonensis. Journal of Mammalogy, 98(4), 1027-1041.
 NASM Flight website
Cassola, F. 2016. Glaucomys volans (errata version published in 2017). The IUCN Red List of Threatened Species 2016: e.T9240A115091392. https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T9240A2225717.... Downloaded on 04 June 2020.
Cassola, F. 2016. Glaucomys sabrinus. The IUCN Red List of Threatened Species 2016: e.T39553A22256914. https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T39553A222569.... Downloaded on 04 June 2020.
"Smithsonian Learning Lab Resource: Southern Flying Squirrel." Smithsonian Learning Lab. 01 Jan. 1970. Smithsonian Center for Learning and Digital Access. 16 Feb. 2021.
National Air and Space Museum, Smithsonian Institution. "Smithsonian Learning Lab Resource: Model, Static, Wright Glider, 1911." Smithsonian Learning Lab. 28 Nov. 2017. Smithsonian Center for Learning and Digital Access. 16 Feb. 2021.