Habitat and Food

North American flying squirrels can be found throughout the North American continent, from Canada down through Central America. G. volans is primarily found in the eastern half of the United States, with isolated populations existing in Central America. G. sabrinus is mostly found throughout Canada but does extend into the northern United States.

Glaucomys volans	Glaucomys sabrinus

Distribution maps courtesy of Smithsonian Institute

Preferred Habitat

G. volans – Southern flying squirrels prefer pine-hardwood forests in temperate to subtemperate climates. There are four such sub-species in the U.S. and Canada. The six recognized subspecies are isolated from each other in subtemperate, montane habitats (Dolan and Carter, 1977). They make their nests in old woodpecker holes or natural cavities in dead or live trees (Whitaker, 1996).
G. sabrinus – Northern flying squirrels make their homes in coniferous and deciduous forests. There are many recorded populations living far south of the norm, mostly in mountain ranges, including the Appalachians, the Black Hills, the Rockies, and the Sierra Nevada (Wells-Gosling and Heaney, 1984). They make their nests in tree hollows, sometimes stealing birds’ nests (Whitaker, 1996).

Food

G. volans snacking, Photo courtesy of FlyingSquirrels.com

G. volans – The southern flying squirrel is the most carnivorous of the tree squirrels. While they do eat nuts, berries, and fungi, they also will eat birds (and their eggs and nestlings), insects, and even other vertebrates, including carrion (Whitaker, 1996).
G. sabrinus – Unlike its southern counterpart, the northern flying squirrel feeds primarily on lichens and fungi, spreading fungal spores and bacteria essential to the growth and survival of surrounding trees. They will also eat a variety of nuts and berries and are known to store large amounts of food for the winter (Whitaker, 1996).

Foraging Behavior

Flying squirrels are, in general, scatter-hoarders. They will forage on the ground (where they are most vulnerable to predation) and either eat what they have found right away or store it in a shallow pocket, either in the ground or a tree, to be eaten later. G. volans will, on occasion, store large amounts of food in a larder cavity, though this behavior has never been observed among G. sabrinus. Flying squirrels will only forage and store food within their home range, which varies in size depending on the availability of food. The unique way in which these squirrels open hard nuts is one way to distinguish where a population is living. They make one ovular, smooth opening in the nut with their incisors to extract the food inside (Patterson, 2008).

Hickory nuts that have been opened by a flying squirrel, courtesy of FlyingSquirrels.com

This website was completed by Kara Earle in partial fulfillment of the requirements for an undergraduate course -- Biology 323: Animal Behavior -- at Davidson College in the Spring Semester 2008.