When winter arrives, you might wonder what happens to squirrels. The truth is that while squirrels do not hibernate in the same way some animals do, they do sleep more during the colder months. Instead of finding a cozy spot to curl up for months, squirrels adapt to the chilly weather by resting longer and slowing down their activity.
During winter, squirrels may still be seen scurrying around in search of food. They often take short naps throughout the day, resting up to 18-20 hours total. This behavior helps them conserve energy and stay warm as they navigate their cold environment. So, if you spot a squirrel seeming less active this season, it’s likely just taking a well-deserved break.
Although tree squirrels do not migrate or go into deep hibernation, they have clever strategies to survive the winter. Understanding how squirrels manage sleep and energy during this time can help you appreciate these agile creatures even more.
Squirrel Hibernation Explained
Squirrels display a fascinating range of behaviors in winter, and hibernation is one of the most intriguing. Understanding how this process works helps clarify the difference between sleeping and true hibernation in squirrels, as well as the specific species that engage in this survival tactic.
Understanding Hibernation
Hibernation is not just a long sleep; it involves significant physiological changes in a squirrel. When ground squirrels hibernate, they enter a state where their body temperature drops, and their metabolic rate decreases drastically. This allows them to conserve energy while they rely on fat reserves built up during warmer months. During hibernation, ground squirrels may wake occasionally, but they typically stay inactive for long periods.
Some species, like the arctic ground squirrel, can even reach states of supercooling, where their body fluids change to prevent freezing. This adaptation helps them survive extreme temperatures in their natural habitats.
Squirrel Species and Winter Behavior
Not all squirrels hibernate. There are two main types: tree squirrels and ground squirrels. For example, tree squirrels, including the Eastern gray squirrel, do not hibernate. Instead, they remain active in winter, often storing food and nesting snugly in tree hollows. They may sleep more during cold spells but do not enter deep hibernation.
On the other hand, ground squirrels, like the thirteen-lined ground squirrel, do hibernate. They create burrows where they can hunker down and safely wait out the winter months. Their hibernation period varies, often lasting several months, depending on their environment.
Physiological Changes During Hibernation
During hibernation, ground squirrels undergo remarkable physiological changes. Their body temperature can drop from around 98.6°F to as low as 40°F, reducing the need for energy. The heart rate also slows significantly, sometimes to just a few beats per minute.
These adaptations are crucial for survival. As they rely on fat reserves, they burn through these stores slowly. This balance ensures they can survive until spring when food becomes more abundant. While in hibernation, ground squirrels may experience deep sleep for weeks, but they can awake briefly to drink water or use the bathroom.
Squirrel Nests and Winter Adaptations
Squirrels have unique ways of handling winter challenges. They build various nests and adapt their behaviors to stay warm and nourished during the cold months.
Nesting Habits of Tree and Ground Squirrels
Tree squirrels, like gray and red squirrels, often create nests called dreys. These dreys are made of twigs, leaves, and insulation materials like moss. They usually build them high in tree branches to provide shelter from the cold and predators.
Ground squirrels, on the other hand, use burrows. These burrows are deeper and more protected from harsh weather. They might also line their burrows with grass or leaves for extra warmth.
Squirrels may share their nests with others during winter. This close proximity helps them retain body heat, making it easier to survive cold nights. Their winter coats become thicker to add extra insulation as temperatures drop.
Surviving the Cold: Insulation and Food Storage
Squirrels have developed several strategies to survive winter’s harshness. Their nests, whether they’re dreys in trees or burrows underground, provide shelter from icy winds.
They also focus on food storage. Before winter, squirrels gather nuts and seeds, burying them in various locations. This practice ensures they have enough food even when snow covers the ground.
In addition to gathering food, squirrels build up fat reserves. These reserves provide energy when food is scarce. By staying active and foraging during warmer parts of the day, they maintain their body heat and adjust to the cold.
With these adaptations, squirrels are well-equipped to handle winter challenges and thrive in their environments.
