Flying Squirrels vs. Gray Squirrels: How to Tell the Difference

If you're hearing noises in your attic at night, you may not be dealing with a gray squirrel at all. You may have flying squirrels, and the difference matters more than most homeowners realize.

Flying squirrels are smaller, more social, harder to exclude, and in some cases, federally protected. They require a different approach than gray squirrels, and companies that don't recognize the distinction can make expensive mistakes. Here's what you need to know.

They Don't Fly. They Glide. And They're Already on Your Roof.

Despite the name, flying squirrels don't fly. They glide using a thin membrane of skin called a patagium that stretches between their front and back legs. When they launch from a high point, they spread their limbs, pull the membrane taut, and glide at an angle of about 25 to 45 degrees. They can steer around obstacles, make 90-degree turns in the air, and brake before landing by raising their tail to shift their trajectory upward.

A typical glide covers 20 to 50 feet. The maximum recorded glide for a southern flying squirrel is over 80 meters, roughly 260 feet. They can cover more distance in a single glide than most homeowners' entire property line.

This means tree trimming, which offers at least some marginal benefit against gray squirrels, is essentially meaningless against flying squirrels. They don't need a branch near your roof. They need a tree anywhere in gliding range, which could be across your yard or in a neighbor's property.

How to Tell If You Have Flying Squirrels

The biggest clue is when you hear activity in the middle of the night. Gray squirrels are diurnal. They're most active in the early morning and late afternoon, and they are almost never active between midnight and dawn. If you're only hearing scratching and scurrying during those daytime hours, it's almost certainly a gray squirrel.

Flying squirrels are primarily nocturnal, but in practice they can be active at any hour. We've had clients with flying squirrel noise around the clock. The key differentiator isn't that flying squirrels are only active at night. It's that gray squirrels are almost never active in the middle of the night. If you're hearing attic activity at 2 AM, gray squirrels are likely off the list.

One other possibility worth mentioning: if the sounds you're hearing are mostly scratching from a consistent location, occurring at odd hours day and night without much movement, consider whether you might be dealing with mice rather than squirrels. Mice produce a steadier, more localized scratching sound from inside walls and ceilings, while squirrels of either type produce more movement, running, and scurrying across open attic spaces.

The sounds themselves can also be distinctive. Flying squirrels are lighter than grays (a southern flying squirrel weighs about 2 to 3 ounces, compared to a gray squirrel's pound or more), so the footsteps are quicker and lighter. Because they live in groups, you'll often hear multiple animals moving at once rather than a single set of footsteps. Homeowners sometimes report hearing the sound of a small nut or acorn rolling across the attic floor at night. If you're hearing that, it's a strong indicator of flying squirrels. They cache food aggressively, storing up to 15,000 nuts in a season, and they're active in and around their food stores throughout the night.

Social Animals, Not Solitary Ones

Flying squirrels are colony animals. They nest communally, especially during colder months, huddling in groups to conserve body heat. A single attic can house 6 to 15 flying squirrels, and colonies of 20 or more have been documented.

They don't just share space. They're genuinely social. Young flying squirrels play-fight and chase each other through the attic, which helps them build coordination and practice the gliding and climbing skills they'll need as adults. These aerial chases can be remarkably noisy for such small animals, especially in the middle of the night when the house is quiet. The social bonds formed through this behavior are part of what makes colonies so persistent. These aren't random individuals sharing a den. They're a group that functions together, returns together, and recruits new members over time.

They Come Back. And They Bring Friends.

This is where flying squirrel problems become fundamentally different from gray squirrel problems.

Southern flying squirrels have documented homing abilities. Research has shown they can return to their nests after being relocated distances of up to one kilometer. If a company traps and removes a few flying squirrels but doesn't seal the entry points, the removed animals may find their way back. Meanwhile, the rest of the colony is still inside.

Even if the removed squirrels don't return, the social nature of the species means new individuals are constantly being recruited into established den sites. A flying squirrel colony in an attic isn't a one-time event. It's a destination. Other flying squirrels in the area will discover and join the colony if the access points remain open.

This is why trap-only approaches fail spectacularly with flying squirrels. You can trap animals out of an attic periodically for years and never solve the problem because the colony replenishes itself. The only solution that works is complete exclusion: seal every entry point with materials they can't chew through, then trap or evict the remaining animals. The order matters, but the exclusion is the part that actually solves it.

Smaller Animals, Smaller Entry Points

A southern flying squirrel can fit through any gap its skull can pass through. That's an opening as small as 0.9 inches wide and 0.7 inches tall. For context, that's significantly smaller than the openings gray squirrels need.

This means entry points that would never admit a gray squirrel are wide open to flying squirrels. Construction seams where two building materials meet, gaps around pipe penetrations, aging soffit joints, and small cracks along the roof-soffit junction can all serve as entry points. Anywhere a flying squirrel can catch a seam in the building envelope, it can start chewing to widen the gap enough to squeeze through.

A thorough exclusion for flying squirrels requires inspecting at a finer level of detail than a standard gray squirrel job. Gaps that seem insignificant have to be sealed. This is roofline work that requires experience, because missing a single half-inch gap means the colony still has a way in.

There's one more complication most people don't expect: flying squirrels don't always enter at the roofline. They are excellent climbers and can traverse up and down inside wall cavities. We've encountered situations where flying squirrels entered at the foundation level, climbed up through the walls, and established a colony in the attic. In larger colonies, the group sometimes splits, with one group denning in the attic while others occupy the space between the basement ceiling and the first floor above. This means a complete inspection can't stop at the roofline. Foundation gaps, basement-level openings, and any penetration in the building envelope from ground to peak has to be evaluated.

Same Risks, Amplified by Numbers

Flying squirrels carry all the same risks as gray squirrels in an attic. They chew electrical wiring, creating the same fire hazard we describe in our post on keeping squirrels out of your attic. They contaminate insulation with urine and feces. They damage stored items and building materials.

The difference is scale. A single gray squirrel can cause significant damage over time. A colony of 10 to 20 flying squirrels, active every night, caching thousands of nuts, gnawing constantly to maintain their teeth, and using your attic as a communal latrine, accelerates every form of damage dramatically. What might take a gray squirrel a full season to accomplish, a flying squirrel colony can do in weeks.

Southern flying squirrels have also been linked to cases of epidemic typhus in humans. The CDC has documented cases of sylvatic typhus transmitted through the fleas and lice associated with flying squirrel colonies. This is rare, but it's an additional reason to take flying squirrel infestations seriously and handle cleanup with proper protective equipment.

A Note on Protected Species

One subspecies of the northern flying squirrel, the Carolina northern flying squirrel, is federally listed as an endangered species. While the southern flying squirrel is the species most commonly found in residential attics throughout most of the tri-state area, homeowners in areas of the country where the Carolina northern flying squirrel lives need to take extra precautions to ensure that wildlife companies are not harming the squirrels during the process of removal.

Killing or harming a federally endangered species carries serious legal consequences. Any flying squirrel removal should be handled by a licensed nuisance wildlife control operator who understands the species distinctions and uses humane methods, including live trapping and one-way exclusion devices, that avoid lethal outcomes regardless of which species is present. If there's any uncertainty, the responsible approach is to treat every flying squirrel as if it could be a protected species.

The Takeaway

Flying squirrels are not just smaller gray squirrels. They're a different animal with different behavior, different colony dynamics, and different exclusion requirements. They're nocturnal, social, persistent, capable of gliding hundreds of feet to reach your roof, and able to enter through gaps half the size a gray squirrel needs.

If you're hearing nighttime activity in your attic, especially if it sounds like multiple animals, the first step is identifying what you're dealing with. The approach that works for a solitary gray squirrel will not work for a flying squirrel colony. Get the identification right, and the solution follows.