You’ll spot squirrels all year, but winter really changes how they get by. Most don’t hibernate for months; instead, they rely on nests, fat, food stashes, thicker fur, and sometimes even sleep in groups to make it through the cold.
These simple tricks help many squirrels stay active and alive through winter without needing to hibernate for long stretches.
Curious about how they build those warm nests or hide food? Or maybe you’ve wondered which squirrels huddle together, which dig burrows, and how their habits mess with gardens and homes. Let’s get into it.
Key Strategies Squirrels Use to Survive Winter
Squirrels stay alive in winter by using shelters, hiding food, growing thicker fur, and sometimes slipping into short sleep-like states. You’ll catch them prepping nests, stashing food, bulking up their coats, and even dropping into brief torpor to save energy.
Building and Choosing Warm Nests and Shelters
You’ll often spot tree squirrels using dreys or tree cavities for shelter. Dreys look like round, leafy nests tucked into forked branches or thick foliage.
Tree cavities give better protection and both tree squirrels and flying squirrels use them when they can. Inside dreys, squirrels line the space with leaves, moss, and sometimes fur or feathers to trap warmth.
Cavities block wind and moisture, and during serious cold, squirrels sometimes share the space to keep each other warm. Ground squirrels take a different route—they dig underground burrows with deeper chambers that stay above freezing.
Watch how squirrels pick sheltered branches, reuse old cavities, or switch between nests depending on wind, predators, or where they’ve hidden food. They’re pretty strategic about it.
Food Gathering, Caching, and Scatter Hoarding
Most tree squirrels scatter-hoard, meaning they bury single nuts in lots of different spots. That way, if a thief finds one, they don’t lose everything.
Each cache sits just under the surface, hidden with leaves or bark. Squirrels use their memory and sharp noses to find these stashes, even under snow.
They go for high-fat, long-lasting foods like acorns, walnuts, and pine seeds. Some, like red squirrels, prefer larder-hoarding and pile up a bunch of food in one spot inside a log or drey.
To protect their food, squirrels sometimes re-hide nuts and keep an eye out for rivals. On warmer winter days, you might see them digging up and snacking on their hidden treats.
Thick Winter Coats and Fat Storage
In winter, squirrels sport thicker, denser fur. Tree squirrels grow a heavier undercoat that traps air and keeps them warm.
Flying squirrels bulk up their fur too, especially around the gliding membrane. As fall approaches, squirrels eat a lot to build up fat under their skin.
That fat fuels them during cold snaps or when food’s scarce. Fat and insulation together mean they don’t need to eat as much when snow covers everything.
If you watch closely, you’ll see them shiver or even huddle together to make extra heat. On really cold nights, two or more might share a cavity just to stay warm.
Hibernation, Torpor, and Sleeping Patterns
Most tree squirrels don’t truly hibernate. Instead, they slip into torpor—short periods where their body temperature and metabolism drop for hours or a couple days.
Torpor helps them save energy during storms without burning through all their fat. Ground squirrels are different; they actually hibernate and can stay dormant for weeks or months with their body temperature way down.
Flying squirrels use shallow torpor too, and often nest in groups to share heat during those rests. On milder winter days, you’ll see squirrels out and about because torpor ends quickly and they need to eat or check their food stashes.
They mix long nest rests with short bursts of activity when the weather lets them.
Diverse Adaptations Among Squirrel Species
Squirrels have their own ways of handling winter. Some hide food, some lower their body heat, and some just pile together for warmth. It’s actually pretty fascinating to see how each type acts, where it nests, and which tricks matter most for getting through the cold.
Eastern Gray Squirrel and Urban Survivors
The eastern gray squirrel (Sciurus carolinensis) hides nuts in lots of small caches all over a neighborhood. You might spot them burying acorns, hazelnuts, and walnuts in lawns, flower beds, or even around tree roots.
Their sharp memory and sense of smell help them recover a surprising amount of buried food, even when snow covers the ground. In cities, gray squirrels shift their activity to midday on cold days to catch warmer hours.
They’ll nest in leaf-filled dreys or hollow tree cavities, and sometimes sneak into attic spaces. You might catch them raiding bird feeders or seed stores when wild food gets scarce.
Red Squirrel and Food Cache Defenders
Red squirrels defend a central larder, called a midd, where they stash cones and seeds. You’ll usually find these midds near evergreens because red squirrels love conifer seeds and guard their cache fiercely.
They use sharp calls and quick, bold moves to warn off intruders. Their small size and agility mean they can dart around branches to keep an eye out for threats.
In winter, they rely almost entirely on their defended cache and, if food runs low, will chew fresh bark or even snack on fungi.
Flying Squirrel: Group Strategies and Gliding
Flying squirrels cut heat loss by nesting together in tree cavities or nest boxes. At night, you might hear their soft calls—they use these to find their roost buddies.
Group roosting means they share body heat and each squirrel spends less energy during long cold spells. These little guys glide from tree to tree on a patagium, a skin flap stretching from wrist to ankle, so they don’t have to risk the ground.
They stick to being nocturnal, feeding on seeds, nuts, and sometimes cached fungi. On really cold nights, some flying squirrels lower their metabolic rate and slip into short bouts of torpor.
Ground Squirrels and Deep Hibernators
Ground squirrels like the California ground squirrel and the arctic ground squirrel actually hibernate to survive winter. You’ll spot them tucked away in burrows, where they drop their body temperature close to freezing.
They slow their heartbeat and breathing for weeks or even months at a time. This huge drop in activity slashes their energy needs.
Arctic ground squirrels do something wild—they can lower their body temperature below 0 °C. Every so often, they wake up just enough to burn some stored fat.
Other ground squirrels, like the thirteen-lined and California ground squirrel, take a different approach. They plug up their burrow entrances and count on fat reserves and body heat they’ve stored up.
This deep hibernation keeps them safe from the brutal cold above ground and the struggle of finding food.
