Ever wonder if squirrels just disappear in winter or if they’re hiding nearby? Most tree squirrels don’t actually hibernate. Instead, they hole up in nests or tree cavities, using short spells of torpor. But some ground squirrels do go into true hibernation, deep in underground burrows. That’s why you might spot a squirrel on a sunny winter afternoon, but rarely during those bitter cold stretches.
Let’s get into which species really hibernate, where they sleep, and how their nests, burrows, and food stashes help them make it through. Next time the woods seem quiet, you’ll know where to look—and maybe even spot a clue that someone’s just snoozing instead of gone.
Where Do Squirrels Hibernate and Which Squirrels Truly Hibernate?
Ground squirrels dig deep and sleep in underground burrows. Tree squirrels, flying squirrels, and most others stay active or just nap in short torpor spells. If you’re looking for true hibernators, check for them in cozy tunnels stocked with food or lined with fat reserves.
Ground Squirrels and Hibernation Burrows
You’ll find ground squirrels tucked away in burrows beneath the frost line. These tunnels keep the temperature steady. Burrows usually have a sleeping nest padded with grass, a separate food stash, and a few escape routes.
The depth and insulation of these burrows help ground squirrels conserve heat and stay safe while they slow their bodies way down. During hibernation, many ground squirrels drop their heart rate and barely breathe for months at a time.
They survive on body fat and whatever food they stored up. Sometimes, one might pop up if the weather warms, but most just stay sealed underground until spring decides to show up.
Tree Squirrels and Winter Dormancy
Tree squirrels don’t really hibernate. Gray squirrels, fox squirrels, and their cousins stick to dreys or tree holes. They sleep more, puff up their fur, and nibble on hidden nuts when it’s not too cold.
You’ll catch them foraging early in the morning or late afternoon. Flying squirrels do things a bit differently. They don’t hibernate either, but they might pile together in a tree cavity to keep warm.
That group snuggling helps them save energy, even if they aren’t fully hibernating. City squirrels do the same—relying on stashed food and a little extra body fat instead of deep sleep.
Species That Hibernate: Arctic and Thirteen-Lined Ground Squirrels
The arctic ground squirrel is a serious hibernator. It can drop its body temperature close to freezing and stay in tundra burrows for up to eight months. Its body handles long torpor and wakes up just enough to keep organs working.
Thirteen-lined ground squirrels also hibernate for real. You’ll find them in grassland burrows, following a clear seasonal routine—fatten up in summer, hibernate in fall, and pop out in spring.
These two are the classic examples of ground squirrels that actually hibernate. Fox, gray, and flying squirrels? Not so much.
If you want more details on which squirrels hibernate and how burrows work, check out ground versus tree squirrel winter behavior.
How Squirrels Survive Winter: Nests, Shelters, and Staying Warm
Squirrels get through winter with nests, tree holes, and hidden food. Let’s look at where they sleep, how mothers protect their babies, and the simple tricks squirrels use to hang onto their warmth.
Squirrel Nests: Dreys and Tree Cavities
You’ve probably noticed those round, leafy dreys high up in the trees. Squirrels build them from twigs, leaves, moss, and grass. The nests sit in branch forks and have a soft-lined cup inside for insulation.
Many squirrels also move into tree cavities or old woodpecker holes if they find them. Cavities beat dreys for warmth and shelter from wind or hungry predators.
Given the choice, squirrels go for tree holes—they hold heat better and keep out the rain. Watch your yard and you might spot squirrels dragging nesting material up a tree. Sometimes they patch up the same drey year after year.
Urban squirrels get creative, too. If natural spots run short, they’ll sneak into attics, eaves, or building gaps.
Where Do Baby Squirrels Sleep in Winter?
Baby squirrels sleep wherever mom puts them—usually deep inside a cavity or at the warmest spot in a drey. Mothers pick sheltered, soft-lined places to keep kits safe from cold and prowlers.
You won’t see babies alone. Mom stays close for warmth and feeding. If a nest gets damaged, she’ll move her babies to a new spot, often under cover of darkness.
The little ones rely on mother’s milk for weeks, so the nest has to stay dry and cozy. When it’s really cold, mothers huddle with their kits to share body heat and cut down on trips outside.
If you ever find a nest with abandoned babies, don’t touch them. Call a local wildlife rehabber. Moving or disturbing the young lowers their odds of making it.
How Squirrels Stay Warm and Safe
Squirrels rely on fat reserves, thick fur, and clever body positions to keep warm. In the fall, they eat extra to build up fat, then slow down during winter days to save energy.
You might spot them with their tails curled over their backs. That fluffy tail works like a cozy blanket, trapping heat right where they need it.
They often huddle together in tree cavities or big dreys. By nesting as a group, squirrels share body heat and don’t need to burn as much energy.
They choose nests that face away from the wind and tuck themselves near dense branches for extra shelter. It’s a smart move, honestly.
When the weather turns rough, squirrels avoid unnecessary risks. They’ll wait for the warmest part of the day to forage and dig up hidden nuts from beneath leaves or shallow soil.
If you want to help them out during harsh cold snaps, try leaving out some high-fat foods like unsalted nuts. Keeping natural tree cover also gives them more nesting spots and safe shelter.
Relevant reading: learn more about how squirrels use nests and cavities from this article on where squirrels go in winter.
