You might wonder where squirrels go in winter. They don’t all just curl up and snooze until spring.
Some species, like ground squirrels, really do hibernate. Others—tree squirrels, for example—just slow down, nap in their nests, and pop out when the weather isn’t so bad.
Let’s dig into which squirrels actually hibernate and which ones just take it easy when it’s cold.
Squirrels get ready for winter by stashing food, growing thicker fur, and building up their nests. That’s how they manage to survive without vanishing completely.
Once you know this, you can spot the difference between a squirrel just hiding out and one that’s truly hibernating.
Let’s look at what separates hibernation from winter dormancy, and how each type of squirrel handles the cold.
Do Squirrels Hibernate?
Some squirrels really do sleep through the worst of winter. Others just slow down and rely on their hidden snacks.
You’ll see which species hibernate, what hibernation actually means, and how their bodies change to handle the cold.
What Is Hibernation?
Hibernation is basically a deep, drawn-out slowdown. Animals do this to save energy when food is hard to find and the cold bites.
During true hibernation, an animal’s heart, breathing, and body temperature drop way down. They live off stored fat for weeks or even months.
That’s not the same as just taking naps or resting more. In real hibernation, animals barely move and might not wake up for long stretches.
Think of it as the ultimate energy-saving mode, but only some mammals can pull it off.
Differences Between Tree Squirrels and Ground Squirrels
Tree squirrels—like gray squirrels and fox squirrels—don’t really hibernate. They just grow thicker fur, hide nuts, and spend more time in their nests (dreys) when it’s cold.
You’ll still spot them on warmer days, maybe raiding your bird feeder.
Ground squirrels, like the thirteen-lined ground squirrel and the California ground squirrel, actually hibernate. They dig burrows and drop into a deep sleep that can last for months.
These ground squirrels lower their body temperature a lot and stay underground until things warm up.
So what’s the main difference?
- Tree squirrels keep moving and eat their stashed food.
- Ground squirrels go deep into dormancy and rely on their body fat.
Squirrel Species That Hibernate
Not every squirrel hibernates. The ones that do are mostly ground squirrels, like those in the genus Spermophilus.
The thirteen-lined ground squirrel is a classic example—it can hibernate up to eight months if it’s really cold. California ground squirrels hibernate too, but only in places where winters get rough.
Most tree squirrels—gray squirrels, fox squirrels, and their cousins—don’t hibernate at all. Flying squirrels stay active all year, though they might take short torpor naps.
If you see a squirrel curled up in a drey during winter, it’s probably just resting, not hibernating.
Physiological Changes During Hibernation
When ground squirrels hibernate, their core temperature drops close to the soil around them. Their heart rate slows from hundreds of beats per minute to just a handful.
Breathing gets shallow and slow. Their metabolism drops to a tiny fraction of what it is in summer.
They also change how their bodies handle waste and energy. Ground squirrels burn stored fat and slow down their kidneys and digestion, so they don’t need to eat or drink much.
Some species wake up for short periods to get their bodies back in balance, then slip right back into torpor.
How Squirrels Survive Winter Without Hibernating
Squirrels get through winter using stored food, body fat, warm nests, and by taking it easy when it’s coldest. You’ll sometimes see them munching on cached nuts during warmer spells.
When storms hit, they hunker down in their nests and might barely move for a day or two.
Food Storage Strategies and Fat Reserves
In fall, squirrels get busy collecting and hiding food. Gray squirrels and fox squirrels scatter thousands of nuts across their territory.
You might catch them burying acorns or walnuts under leaves or in the dirt. Later, they use their memory and sense of smell to dig up these snacks when they need them.
Red squirrels do things differently. They build one big stash called a midden, so they don’t need to travel as much in bad weather.
Squirrels also eat more in autumn to fatten up. That extra fat helps them get through cold snaps and powers them during short torpor periods.
Dreys, Burrows, and Winter Nests
Dreys—those messy-looking nests made of leaves and twigs—sit high in tree forks. They give gray and fox squirrels some protection from wind and cold.
Squirrels line their dreys with shredded bark and softer stuff for extra warmth. Sometimes, you’ll see several dreys in the same tree; squirrels like to have backup spots if one gets ruined.
Some squirrels will use tree cavities or even attics for better shelter. Cavities do a better job blocking wind and keeping the temperature steady.
Ground squirrels dig burrows and hibernate there, but tree squirrels stick to dreys and cavities. If you notice chewed wood or nests in your attic, a squirrel probably found a cozy winter spot.
Raising Baby Squirrels in Cold Months
Sometimes, you’ll come across baby squirrels in late winter. That usually means the mother planned her timing so the babies would have food in spring.
Mothers use tree cavities or well-insulated dreys to keep the babies warm. You might see the mom leave the nest to go find food, but she’ll come back often to nurse and groom the little ones.
Cold snaps can be tough on the babies, so mothers pick the warmest, deepest dens they can. It’s best not to touch healthy nests—human scent can sometimes cause the mother to abandon them, though that’s rare.
If you find a baby squirrel that looks injured or really cold, you should reach out to a licensed wildlife rehabilitator.
Where Do Squirrels Live When It’s Cold?
When winter hits, gray and fox squirrels bounce between their nests and quick foraging trips. You’ll probably spot them on those rare sunny days when the temperature finally creeps above freezing.
If a blizzard rolls in, most squirrels just hunker down in their dreys or tree cavities and wait for the worst to pass. It’s not like they enjoy being out in that mess.
Where you live makes a difference. Squirrels in the southern states pretty much stay active all year. Up north, though, they use torpor more often and really rely on their food caches.
Ground squirrels and chipmunks? They stick to their burrows and can actually hibernate, which is a whole different ball game. But your typical backyard gray squirrel probably lives in trees, attics, or whatever cozy spot they can find.
They get by on stored food and whatever insulation their nests can provide. If you want to dig deeper into these quirky behaviors, check out how squirrels survive winter on BackyardPests.
