New York State is home to two species of flying squirrels. These small, arboreal mammals are often mistaken for regular tree squirrels, but their secretive, nocturnal nature keeps them largely hidden from human sight. Their existence highlights the surprising biodiversity present in the state’s woodlands.
New York’s Two Flying Squirrel Species
The two species found in the state are the Northern Flying Squirrel (Glaucomys sabrinus) and the Southern Flying Squirrel (Glaucomys volans). Distinguishing them requires examining their size and fur characteristics, as their overall body shape is similar due to their gliding adaptation. The Northern Flying Squirrel is the larger species, typically measuring 10 to 12 inches in total length. Its belly fur is gray at the base and white at the tip, giving the underside a slightly darker appearance. Conversely, the Southern Flying Squirrel is smaller, averaging 8 to 10 inches long, and its belly fur is completely white from base to tip.
The Northern species tends to be reddish-brown, while the Southern species is often a mouse-like gray. The Northern Flying Squirrel is also more tolerant of cold temperatures and does not become torpid during winter, unlike its Southern counterpart.
Geographic Distribution Across the State
The two species occupy distinct geographic ranges within New York, primarily segregated by elevation and forest type. The Southern Flying Squirrel is the more widespread of the pair, favoring lower elevations and mature, deciduous forests, particularly those with oak and hickory trees. Its range extends across the lower two-thirds of the state, often south of the Mohawk River Valley. The Northern Flying Squirrel is restricted to a patchier distribution in the state’s higher elevations. It is found in the dense, boreal, or mixed coniferous/deciduous forests of the Adirondack and Catskill mountain regions.
These high-altitude habitats provide the cooler climate and specific food sources, such as lichens and fungi, that the Northern species prefers. Both species require large areas of mature forest with numerous tree cavities, which they use for nesting and cover.
Nocturnal Habits and Gliding Mechanics
Flying squirrels are strictly nocturnal, emerging from their nests at dusk. This nighttime activity is facilitated by their large, dark eyes, which are highly adapted for navigating the low-light conditions of the forest canopy. They spend most of their time in the trees, only occasionally descending to the forest floor to forage.
These animals do not fly like a bird or bat; instead, they are expert gliders. Their ability to glide comes from a furry membrane called the patagium, which stretches from their wrist to their ankle on each side of the body. When they launch from a high point, they spread their limbs wide, causing the patagium to stretch taut and form a square-shaped aerodynamic surface. The squirrel uses slight movements of its limbs and a flattened tail as a rudder to steer and control the glide path, allowing for impressive maneuverability. They can cover distances well over 150 feet in a single glide, effectively crossing the gaps between trees without touching the ground.
Their diet is omnivorous, consisting of nuts, seeds, fungi, fruits, and insects. The Southern species is known to be slightly more carnivorous, occasionally eating bird eggs or carrion. During cold New York winters, flying squirrels are highly social and often engage in communal nesting. Multiple individuals, sometimes a dozen or more, will pile into a single tree cavity to conserve body heat and energy.