Squirrels typically spend the end of summer and fall bulking up to prepare for winter. This gives them an extra layer of fat to keep their body temperatures higher, which means they consume less energy. However, once the winter arrives most squirrels don’t hibernate like other animals in the wild.
Instead, they sleep. According to the College of Environmental Science and Forestry, most squirrels are diurnal, meaning they wake up at dawn and dusk but sleep throughout the day and night. They typically only come out at midday to forage for food. This behavior helps them conserve their energy for important tasks, such as breeding and building nests.
The answer to “where do squirrels sleep in winter” depends on the type of squirrel. Ground squirrels hibernate for up to five months of the year, but tree squirrels don’t. Tree squirrels, which are typically found on or near the ground, rely on a combination of insulated dens they build themselves (known as dreys) and thick fur to protect them from the winter cold.
The dreys squirrels build themselves are typically located in the forks or hollows of trees, although they will sometimes dig into a shed, barn or attic to escape the cold. If the winter weather is exceptionally harsh, a group of squirrels will often share the same drey for added warmth. However, solitary squirrels tend to be territorial, so they may squabble for the best spot in the den.