You might notice way fewer squirrels out and about once winter hits, but that doesn’t mean they’re all snoozing until spring. Actually, some squirrels—mostly ground squirrels—hibernate deep in burrows, while most tree squirrels stay awake and hunker down in nests or tree cavities.
So, why do ground and tree squirrels act so differently in winter? Let’s get into how they prep for cold weather and where they like to hide out.
You’ll get some practical details here about where squirrels go, how long they stay put, and what that could mean for your yard or maybe even your attic.
Do Squirrels Hibernate or Stay Active in Winter?
Squirrels don’t all handle winter the same way. It really depends on the species and where they live.
Some squirrels keep moving, digging up hidden food and curling up in nests, while others spend months in a deep sleep underground.
Types of Squirrels: Tree Squirrels vs. Ground Squirrels
Tree squirrels—think eastern gray or fox squirrels—don’t hibernate. You’ll spot them digging up nuts they buried earlier or lounging in their leafy dreys and tree holes.
They bulk up in the fall, growing thicker fur and storing fat so they can keep foraging on cold days.
Ground squirrels, like prairie and Arctic types, do hibernate. These guys stash fat and then disappear into burrows for months.
The arctic ground squirrel can actually stay inactive most of the year, only popping out for a short summer.
If you’re living near trees, you’re probably seeing tree squirrels that stay active all winter. On the other hand, burrow systems in open fields usually belong to ground squirrels that hibernate.
True Hibernation vs. Torpor in Squirrels
True hibernation is pretty intense. Ground squirrels drop their body temperature, heart rate, and breathing way down for long stretches.
Some ground squirrels slow their hearts to just a few beats per minute and barely breathe at all.
Torpor is different. It’s a short, temporary drop in metabolism. Tree squirrels use torpor during really cold nights or nasty storms.
You might notice one curled up and barely moving for a day or two—that’s torpor, not hibernation.
Some species switch things up. Ground squirrels wake up every now and then during hibernation.
Tree squirrels can go into torpor multiple times if food is running low.
How Squirrels Adapt to Cold Temperatures
Squirrels have some clever ways to handle the cold. They grow thick winter coats and build super-insulated nests—dreys—in tree hollows or piles of leaves.
On the coldest nights, you might see a few tree squirrels sharing a den just to stay warm.
They count on hidden food and stored body fat too. Tree squirrels bury nuts all over and sniff them out even under snow.
Ground squirrels pack on fat before hibernating, surviving months without eating.
When the temperature drops fast, squirrels shiver for warmth or wrap their tails around themselves like a blanket.
If you watch closely on milder winter days, you’ll see them darting around, staying busy and feeding.
Where Do Squirrels Hibernate or Shelter During Winter?
Squirrels have a few main tricks for staying safe and warm once winter rolls in.
Most tree squirrels remain active in nests high up, while ground squirrels can sleep underground for ages.
Dreys and Tree Nests
Tree squirrels like gray and fox squirrels build round nests—dreys—up in the branches or tucked into thick foliage.
They use twigs, leaves, and moss, then line the inside with grass, fur, or feathers for extra warmth.
You’ll usually find dreys 20–60 feet up in hardwoods, close to good food sources like oaks or walnuts.
Dreys shield squirrels from wind and light snow, but when they can, squirrels move into deep tree cavities for better protection.
Cavities keep out predators and block heavy storms. If you spot a squirrel fussing with a nest, it’s probably adding insulation before a cold front.
Sometimes, tree squirrels share dreys on bitter nights, but most still keep separate nests and rotate between them.
You’ll notice them leaving on warmer winter days to dig up cached nuts.
Ground Burrows and Underground Hibernation
Ground squirrels dig burrows with special chambers for sleeping and food storage.
Many ground squirrels enter true hibernation in these burrows, dropping their heart rate and body temp for months.
Burrow depth helps keep things warm and steady, which is pretty essential for surviving harsh freezes.
If you live near prairies or open fields, look for small dirt mounds or several tunnel entrances—that’s usually a ground squirrel’s setup.
Burrows often have separate nesting rooms lined with grass.
Not every ground squirrel hibernates for the same amount of time; it really depends on the species and the climate.
Even during hibernation, ground squirrels might wake up on warmer days.
You could catch a glimpse of light activity near burrow entrances in late winter as they pop out to snack or check their tunnels.
Baby Squirrels and Winter Nesting Habits
When babies arrive late in the year, mothers look for the warmest shelter they can find. You’ll spot nests tucked inside tree cavities or in sturdy dreys, with the mother adding extra padding for warmth.
Baby squirrels stay hidden, relying on their mom for food, until they’re strong enough to climb and start foraging. Honestly, their odds of making it through winter hinge on where the mother builds the nest and how much food she’s stashed away.
In places like cities or suburbs, mothers get creative. Sometimes they’ll use empty bird nests, squeeze into attic spaces, or settle into thick shrubs if there aren’t enough trees around.
Notice a nest that doesn’t move much but has an adult dropping by again and again? There’s a good chance it’s full of little ones waiting out the cold.
As temperatures dip, mothers barely leave the nest. They’ll haul in stored food and only venture out for quick, warmer moments, just to keep their pups safe.
