Flying Squirrels in New Jersey: How to Identify Them, Northern vs. Southern, Life Cycle, and the Damage They Can Cause

Short answer: New Jersey has two flying squirrel species. The southern flying squirrel is widespread and is almost always the one in your attic; the northern flying squirrel is rare and limited to colder high-elevation forest. They are nocturnal, glide rather than fly, and often live in colonies, so one sighting rarely means one animal.

Quick answer: What species of flying squirrel lives in NJ?

New Jersey has two species of flying squirrel:

• Southern Flying Squirrel (Glaucomys volans): widespread and abundant in New Jersey
• Northern Flying Squirrel (Glaucomys sabrinus): rare in New Jersey and typically restricted to high-elevation, colder forest zones (think spruce/fir conditions, not suburban neighborhoods)

So for most homeowners in North Jersey, Central Jersey, and South Jersey, the flying squirrel you're hearing (or briefly spotting at dusk) is almost always the Southern Flying Squirrel.

"Flying" squirrels don't actually fly (but they do glide)

Flying squirrels glide using a stretchy membrane of skin called a patagium that extends between their front and hind legs. They launch from trees (or rooftops) and steer with their tail, making controlled glides to another trunk.

That's why many New Jersey sightings happen at dusk, around wooded neighborhoods, and near mature trees that touch or overhang roofs.

Northern vs. Southern flying squirrels in New Jersey: how they differ

Southern Flying Squirrel (the "NJ one" for most people)

Where in NJ? Most forested and suburban wooded areas statewide.

Habitat: Often associated with hardwood/deciduous forests and wooded neighborhoods.

Personality: Highly social. It commonly forms groups and colonies, especially when shelter is good and winters are cold.

Northern Flying Squirrel (rare in NJ)

Where in NJ? Rare; generally limited to high elevation, colder forest conditions.

Habitat: Coniferous and mixed coniferous forests are core habitat across its range.

Bottom line for homeowners: If you're in typical residential NJ (Bergen, Essex, Morris, Passaic, Union, Somerset, Monmouth, Ocean, Camden, Burlington, etc.), nuisance issues are overwhelmingly tied to Southern Flying Squirrels.

Habits in New Jersey: what flying squirrels do all night

Flying squirrels are strictly nocturnal, which explains why you'll hear them far more than you'll see them.

In the wild, they nest in tree cavities, move through the canopy, and feed on nuts, seeds, buds, fungi, and sometimes insects and eggs (they're opportunistic).

In neighborhoods, their behavior changes based on one key factor:

Shelter beats everything

If they find a warm, protected place (like an attic or wall void), they'll return, often with friends.

Why you may have more than one: colonies and communal living

One of the most surprising facts for NJ homeowners is that flying squirrels can be highly social and may share nesting areas, especially when temperatures drop.

That means you might not be dealing with "a squirrel." You could be dealing with multiple flying squirrels using the same entry points and nest areas.

This is also why DIY attempts sometimes feel like they "work" until the noises return.

Mating and life cycle: when flying squirrels have babies in NJ

Southern Flying Squirrel reproduction (what matters for NJ homes)

Southern flying squirrels can breed twice per year, with breeding peaks often occurring in late winter to early spring and again in late spring into summer.

• Gestation: about 40 days
• Nursing/weaning: young are cared for for about 8 weeks, with weaning beginning around 6 weeks

Why this matters: If flying squirrels are in your attic in late winter/spring or again in early-to-mid summer, there's a real possibility a nest is being used for raising young. Humane, professional work plans around that reality.

Northern Flying Squirrel reproduction (less relevant for most NJ homes)

Northern flying squirrels typically have a breeding season in spring (often late March through May) and commonly produce one litter per year.

The real issue in homes: damage and contamination

Flying squirrels are cute. In the forest, they're important wildlife. Inside a structure, they can cause expensive problems fast.

1) "Communal bathrooms" (latrines) = concentrated odor + staining

Flying squirrels often use latrine sites, meaning droppings accumulate in piles instead of scattering everywhere. This can create strong odors, and contamination can seep into building materials.

NJ homeowner clue: If you find droppings that look clustered into "toilet corners," flying squirrels jump to the top of the suspect list.

2) Chewing and fire risk

Like other rodents, squirrels gnaw to manage continuously growing incisors. In attics, that can mean chewed wood, shredded insulation, and potentially damaged wiring (a serious hazard).

3) Noise and sleepless nights

Because they're nocturnal, activity often peaks when you're trying to sleep: scratching, scurrying, and "rolling" or thumping in ceilings and walls.

4) Entry points are usually small and high

Flying squirrels can use very small construction gaps near soffits and fascia, rooflines, gable vents, and returns where different materials meet.

Signs you may have flying squirrels in your NJ attic or walls

Look for a combination of:

• Noises at night (especially after 10pm to pre-dawn)
• Latrine piles of droppings in one or a few consistent areas
• Staining or odor near ceilings, attic access points, or upper wall corners
• Rub marks or smudging near roof edges and entry points (from repeated use)

Prevention in NJ: how to reduce the odds they move in

Flying squirrels are doing squirrel things. Your job is to make your home a bad "nest site."

Practical steps that help:

• Trim tree branches back from rooflines (reduce easy glides onto the house)
• Repair and secure soffit and fascia gaps (small openings matter)
• Screen and secure vents properly (gable, ridge, bathroom exhaust terminations)
• Address moisture and odor sources in attics and crawl spaces (attractants vary, but shelter is #1)

What to do if you already have flying squirrels in your house

If you suspect flying squirrels in New Jersey, focus on three things:

• Confirm the species and entry points (a real inspection, not a guess)
• Humane removal and exclusion that prevents re-entry (especially important with colony behavior)
• Sanitation and restoration if latrines have built up (odor and contamination can linger)

Acorn Wildlife handles all three as part of professional flying squirrel removal across South Jersey.

Are flying squirrels dangerous?

They are not typically aggressive, but inside a home they can create serious risks through contamination (latrines) and structural or electrical damage.

Why do I only hear them at night?

Flying squirrels are nocturnal.

If I remove one, will that fix it?

Not always. Flying squirrels can be social and may share nesting areas, especially in colder months, so the real solution is identifying and securing entry points after proper removal.

Related: Flying Squirrel Removal in South Jersey · Squirrels in the Attic in New Jersey: Signs, Risks, and What to Do · Why Squirrels Get Into NJ Homes Before Fall