Are There Flying Squirrels in Illinois?
Yes, flying squirrels live in Illinois, though they're found primarily in southern and central regions. The Eastern Flying Squirrel inhabits forested areas across most of the state. These small nocturnal gliders prefer mature hardwood forests and mixed woodlands. Flying squirrels are present but declining in northern Illinois as urban development has eliminated suitable habitat and fragmented forest patches.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated July 22, 2026.
Carolina Northern Flying Squirrel · Evan M. Raskin CC BY
Southern Flying Squirrel · Hila Taylor CC BY
Southern Flying Squirrel · Nik Hughes CC BY
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- GBIF records
Yes, flying squirrels are in Illinois. Next you'll want:
Yes, flying squirrels live in Illinois, though they're found primarily in southern and central regions. The Eastern Flying Squirrel inhabits forested areas across most of the state. These small nocturnal gliders prefer mature hardwood forests and mixed woodlands. Flying squirrels are present but declining in northern Illinois as urban development has eliminated suitable habitat and fragmented forest patches.
Where Flying Squirrels Are Found in Illinois
Flying squirrels are distributed throughout Illinois in suitable forest habitats, with the highest populations concentrated in southern portions of the state. The Shawnee National Forest in southern Illinois provides the most strong flying squirrel populations and reliable habitat. Forests along the Wabash River valley contain established populations across southern Illinois's Ohio River drainage. The Cache River wetland complex in southern Illinois harbors flying squirrels in its bottomland hardwood stands. Central Illinois forests in the Danville region and surrounding counties contain populations, though habitat is increasingly fragmented. Northern Illinois populations have declined substantially as urban sprawl and agricultural expansion eliminated forests. The Illini Bluffs area along the Illinois River valley in central Illinois supports scattered populations. Forests in Vermilion and Iroquois counties contain flying squirrels in remaining woodlots. Southern Illinois's Mississippi River floodplain forests provide excellent habitat. The Embarras River drainage supports populations throughout east-central Illinois. They're essentially absent from heavily agricultural northwestern Illinois. Visit ourIllinois wildlife guidefor information about other forest-dwelling mammals. Flying squirrels require large trees and forest continuity, making them increasingly rare as forests become fragmented.
Season and Activity in Illinois
Flying squirrels in Illinois are active year-round with marked seasonal patterns in behavior and food availability. Fall is their most active season as they gather and cache hickory nuts, acorns, and other seeds in preparation for winter. Late September through November sees peak food-caching activity driven by acorn abundance from white oaks, red oaks, and swamp oaks. Winter activity decreases significantly as cold temperatures limit foraging, though they remain active on milder nights accessing cached food. Extreme cold confines them to dens where multiple individuals huddle together for warmth. Spring mating begins in late winter and February with females giving birth to first litters in April and May. Summer brings abundant insects and berries, diversifying their diet beyond seeds and nuts. A second breeding cycle occurs in mid-summer with young maturing by early fall. Illinois's variable winters, ranging from mild to severe, create fluctuating survival pressures from year to year. Years with abundant acorn crops support larger populations. Fall acorn crop failure can cause winter starvation in flying squirrels. Most activity occurs between two hours after sunset and three hours before dawn. Peak visibility times occur in fall and early winter when foraging intensity increases. For more on flying squirrel in Illinois, see ourIllinois flying squirrel guide.
How to Identify a Flying Squirrel
Flying squirrels are among Illinois's smallest tree-dwelling mammals, weighing just two to three ounces and measuring six to eight inches head and body length. Their defining feature is the patagium, a loose fold of skin stretching between front and hind legs that serves as a gliding surface. When at rest on tree trunks, this membrane is barely visible and they appear similar to small regular squirrels at first glance. Large, dark eyes are perfectly adapted for night vision in dark forest environments. Their fur is soft and silky, gray to gray-brown on the back with pure white underparts and belly. The gliding membrane's underside is also white, creating a striking appearance during flight. Their tail is flattened and fringed with hair, functioning as balance and rudder during glides. Ears are small and rounded, less prominent than gray squirrels' prominent ear tufts. They produce high-pitched chirps, squeaks, and clicking vocalizations, far quieter than daytime squirrels. Males and females appear identical externally, though females are slightly larger in average body size than males. You can also browseIllinois wildlife.
Where Sightings Concentrate in Illinois
Flying squirrel sightings in Illinois concentrate in the remaining mature forests, particularly in southern portions of the state. The Shawnee National Forest provides the most consistent sighting opportunities year-round. The Cache River National Wildlife Area in southern Illinois consistently produces sightings in its bottomland hardwood forests. The Wabash River drainage forests from the Ohio border northward contain populations in counties like Massac, Gallatin, and Pope. Ferne Clyffe State Park and surrounding forests in south-central Illinois harbor flying squirrels. The Dongola Bluffs area in southern Union County provides concentrated habitat. Forests in Hamilton and Saline counties along the Little Wabash River contain populations. The Illini Bluffs region in central Illinois offers sighting possibilities. Devil's Canyon State Natural Area contains flying squirrel habitat. Forests in Coles County provide populations in scattered woodlots. Most concentrated populations require large, continuous forest patches with mature oaks, hickories, and mixed hardwoods. Forests with abundant old trees and natural cavities support the largest populations. Northern Illinois sightings have become increasingly rare due to habitat loss and fragmentation.
Typical Behavior and Diet
Flying squirrels in Illinois are strictly nocturnal, spending daylight hours hidden in tree cavities or leafy dreys constructed high in the canopy. They emerge shortly after dusk and conduct nearly all foraging, movement, and social activity during darkness. Gliding is their primary mode of travel between trees, allowing rapid movement through forest canopies while minimizing predation risk. Their diet consists primarily of acorns, with white oak and red oak nuts being strongly preferred when available. Hickory nuts, particularly shagbark hickory and pignut hickory, supplement their diet. They consume seeds from elm, maple, and hackberry trees. In fall, they actively cache thousands of nuts in scattered locations for winter use. Fungal consumption, particularly truffles and mushrooms, occurs seasonally. They hunt insects including moths and beetle larvae, particularly during summer months. Winter survival depends almost entirely on accessing cached food stores accumulated during fall. Flying squirrels are highly social and share winter dens with family members, huddling together for warmth during severe cold. Illinois's cold winters create intense survival pressures on flying squirrel populations. Territory sizes are small, typically less than five acres. Food availability varies annually based on oak and hickory crop success.
Coexistence and Legal Protections
Flying squirrels are protected wildlife in Illinois and cannot be trapped, hunted, or kept without permits from the Illinois Department of Natural Resources. These shy creatures actively avoid human contact and rarely cause problems around homes or properties. If a flying squirrel enters your home, contact a licensed Illinois wildlife removal professional for safe exclusion repair. Flying squirrels do not carry rabies at significantly higher rates than other wildlife. They pose minimal disease transmission risk to humans. They're beneficial forest residents that disperse fungi and seeds throughout the ecosystem. Protecting flying squirrels requires maintaining mature hardwood forests with cavity-bearing trees and canopy continuity. Dead snags provide essential nesting and denning habitat. Forest fragmentation is flying squirrels' primary threat in Illinois, as habitat patches become isolated. Illinois wildlife management encourages landowners to maintain forest connectivity and preserve old-growth characteristics. If you find an injured flying squirrel, contact a wildlife rehabilitator. Reporting sightings to the Illinois Department of Natural Resources helps biologists track population status and habitat needs. Learn more aboutIllinois flying squirrel populationsand their conservation.
Species People Confuse with Flying Squirrels
The Eastern Gray Squirrel is the most common source of confusion, as both are tree-dwelling rodents found in Illinois forests. Gray squirrels are significantly larger and completely lack gliding membranes. Fox Squirrels are even larger than gray squirrels with distinctive white facial markings. Eastern Chipmunks are much smaller with characteristic stripes along their backs and sides. They're primarily diurnal, making them easy to distinguish from nocturnal flying squirrels. Red Squirrels are smaller than gray squirrels but much larger than flying squirrels and cannot glide. Virginia Opossums occasionally cause confusion when spotted in trees at night, but they're considerably larger. Raccoons are much larger and cause more extensive property damage. Ground squirrels like the thirteen-lined ground squirrel are terrestrial and lack arboreal adaptations. Mice and voles are much smaller and ground-dwelling. Southern Flying Squirrels are nearly identical to Eastern Flying Squirrels but don't occur in Illinois. Understanding thesewildlife identification featureshelps distinguish Illinois forest mammals.
Frequently Asked Questions
Q: Why are flying squirrels disappearing from northern Illinois? Urban development, forest fragmentation, and agricultural expansion eliminate continuous forest habitat that flying squirrels require for movement and survival. Q: How do flying squirrels navigate in complete darkness? Their large eyes and sensitive whiskers allow efficient movement through forests even on moonless nights. Q: Can flying squirrels transmit diseases to people or pets? Flying squirrels rarely contact humans or domestic animals and do not carry rabies or other significant zoonotic diseases. Q: What's causing flying squirrel populations to decline in Illinois? Forest loss, fragmentation, and lack of old-growth characteristics in remaining woodlands reduce suitable habitat and isolate populations. ExploreIllinois's flying squirrel habitatthrough our wildlife resources.
Plan your flying squirrel sighting in Illinois
308 verified flying squirrel records have been logged in Illinois, most recently in 2026. See the GBIF records.
Where to look in Illinois
- Lewis & Clark National Historic Trail · Wildlife Watching · Find hotels
- Lincoln Home National Historic Site · Wildlife Watching, Birdwatching · Find hotels
- Emmett Till and Mamie Till-Mobley National Monument · Find hotels
- Mormon Pioneer National Historic Trail · Find hotels
- New Philadelphia National Historic Site · Find hotels
- Pullman National Historical Park · Find hotels
More places to see flying squirrel
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