We see squirrels sitting on trees, raiding the bird feeders and gardens, and digging up holes to store nuts for the winter.
Squirrels are less active during colder months, and you may ask the question: Do squirrels hibernate during winter? The simple answer is no. However, some squirrels do.
So what do most squirrels do during winter?
In this article, we will dig into the world of squirrels to find out why they don’t hibernate and what exactly these little creatures do during winter.
For more reading, check out our list of 19 squirrel facts, some of which might surprise you.
When exploring if squirrels hibernate, let's first look at what hibernation means.
Hibernation is an animal survival mode that involves a state of dormancy for warm-blooded animals. In this state, temperature, breathing rate and heart rate, and other metabolic activities drop to allow animals to conserve energy and survive during colder weather.
Hibernation is more than deep sleep. The animal’s body shuts down, reducing the animal’s metabolism. They then rely on fat reserves for the energy they need to continue to breathe and stay alive and warm. This way, the animal doesn't have to search for food and water. They also don’t need to get rid of waste.
Hibernation could take place for a few days and even months. In the animal kingdom, hibernation means different things. For example, insects go through what is called diapause. This is an extended period of extreme inactivity which could last for years.
We get to enjoy the playfulness of tree squirrels running around during the summer and autumn seasons. They are more active during daylight hours. Some tree squirrels are also early risers. Like the eastern gray squirrel, other squirrels prefer the sunset to the sunrise. However, as the temperature begins to dip, we see fewer squirrels around.
As we mentioned earlier, not all squirrels hibernate during winter.
Ground squirrels are the only real hibernating squirrels. They can reduce bodily functions like heart rate, breathing, and other metabolic activities. This will enable the ground squirrel to survive without eating, drinking, urinating, and carrying out other body functions during winter.
Other squirrel species don’t have the same body mass as ground squirrels and cannot hibernate. Other squirrel species will need to eat, pee and carry out metabolic functions at some point during the cold seasons.
Most squirrels do not hibernate because they don’t need to. A squirrel simply prepares for the coming winter, gathering enough to last them the entire winter season. Thanks to their photo-neuroendocrine system, a squirrel simply knows when the autumn season is wrapping up and begins to prepare for the winter.
During the winter, squirrels live in what is called dreys. The ground squirrels live in burrows deep in the ground, while the tree squirrel lives in dreys on trees.
Generally, squirrels build themselves a drey using branches and twigs. They work to make sure their nest is warm during cold temperatures. Also, they build multiple nests as a backup plan.
Squirrels typically nest alone unless they have their young. You can find squirrels nesting on tall trees, attics, and garages. Cleaning your gutter of nuts, acorns, and leaves is a good way to ensure squirrels stick to trees and prevent them from scampering around your garage or attic.
During the winter season, food supplies are scarce, and weather conditions are harsh. So what do squirrels do during winter? Well, squirrels have to do a lot of preparation to ensure they survive the long winter season.
Squirrels build nests all year round. However, during the winter, squirrels make a thicker version of their summer nests. They use lots of leaves, twigs, and moss to thicken and keep their nests well-insulated.
Squirrels tend to build more nests during the warmer seasons and stay in them during the winter to conserve their energy. They also build nests in different locations as a survival technique against predators. Squirrels also grow thicker fur to help them survive the harsh weather and retain heat from the winter sun. These extra thick furs give the squirrel a thick and darker appearance.
Secondly, since there isn’t as much food during the winter months, tree squirrels create food caches during summer. They store foods like berries, nuts, seeds, and insects. They stash food across different locations to ensure continuous supply and prevent it from being used up by other animals.
Once the winter weather starts, they use their special memory and a strong sense of smell to locate and move their food to other locations accurately.
Also, squirrels try to eat as much as they can during the summer to store body fat. This body fat is known as brown fat, and it helps protect them from the harsh winter weather conditions. It also provides energy when the food supply is limited.
Squirrels fall into winter rest, reducing their activities from long hours of daily activity to about 4-5 hours. During this period, squirrels spend their time collecting and eating their food. They rely on the brown fat to survive for days without eating. If weather conditions are extreme, squirrels can spend a few days sleeping.
There are more than 200 squirrel species, and each behaves differently during the winter season. Let’s look at some of the most common species and what they do when the temperature begins to dip.
As the name suggests, ground squirrels live on the ground and in burrows. During warmer seasons, the ground squirrel uses the burrow as a shade to regulate its temperature. During the winter seasons, the ground squirrels hibernate deep underneath the burrows. They sometimes hibernate together with several other ground squirrels. Typically, the ground squirrel hibernates for around 5 to 8 months.
Unlike the ground squirrels, gray squirrels take a winter rest. They build their nests in trees to protect themselves from harsh weather elements. They store food in large quantities during the summer and come back to collect their food supplies during the winter. During the winter, gray squirrels spend their time sleeping for long periods. They may even sleep for as long as a few days.
Just like gray squirrels, red squirrels go around making nests and storing food for the winter. Red squirrels prefer to nest in thick evergreen trees, using tree cavities for more protection.
Like grey squirrels, red squirrels sleep for long periods during winter.
These squirrels have long and slender limbs, large eyes, and a long and bushy tail which could be cylindrical or flattened. Unlike other squirrels, flying squirrels spend their winter nesting in groups. By doing this, they can lower their metabolic rates to conserve energy. However, food consumption increases when they nest in groups. You may see some squirrel activity for short periods during the winter nights.
The fox squirrel is the largest species native to North America. Fox squirrels dwell on large trees and open forests. They do not hibernate but build warm nests and store foods like nuts, berries, and insects for the winter.
Fox squirrels are solitary squirrels. However, they may nest together during the winter breeding season. For example, the female fox squirrel nests together with her young during winter.
Some animals like birds migrate due to seasonal changes, water, food searches, and environmental changes. However, most squirrels tend to stay where they are unless in search of a new habitat. This could result from unfavorable environmental conditions like flooding, fire, famine, etc. Squirrels do not return to their home when they migrate but move permanently to their new habitat.
Squirrels go through periods of dormancy during the winter. Ground squirrels are the only species that hibernate in winter. Other tree squirrels go through winter rest to endure harsh winter conditions.
Jen’s a passionate environmentalist and sustainability expert. With a science degree from Babcock University Jen loves applying her research skills to craft editorial that connects with our global changemaker and readership audiences centered around topics including zero waste, sustainability, climate change, and biodiversity.
Elsewhere Jen’s interests include the role that future technology and data have in helping us solve some of the planet’s biggest challenges.