top of page

Do Tree Squirrels and Ground Squirrels Hibernate in The Winter?

Updated: Nov 4

Introduction to Squirrels and Their Behaviour



Squirrels are fascinating wild animals that have captured the interest of many nature enthusiasts. These small mammals are known for their agility, bushy tails, and habit of gathering and storing food. Various squirrel species are found worldwide, each with unique adaptations and behaviours. In this article, we'll explore the intriguing question: Do squirrels hibernate?



To understand squirrel behaviour, it's essential to recognize the differences between various squirrel species. The most common types include tree squirrels (such as the eastern grey squirrel, red squirrels, and flying squirrels) and ground squirrels. Each species has developed specific adaptations for survival in its respective habitats.


 

What is Hibernation?


Before delving into whether squirrels hibernate, let's define hibernation. Hibernation is a state of inactivity and metabolic depression in animals, characterized by lower body temperature, slower breathing, and lower metabolic rate. During hibernation, an animal's body essentially shuts down to conserve energy during periods of extreme cold or food scarcity.

It's important to distinguish between true hibernation and a similar state called torpor. While hibernation involves long periods of deep sleep and significant physiological changes, torpor is a shorter-term state of decreased physiological activity, typically lasting less than 24 hours. Some squirrels enter a state called torpor during freezing spells, which helps them conserve energy.


 


Types of Squirrels and Their Habitats


Squirrels can be broadly categorized into two main groups: tree squirrels and ground squirrels. Tree squirrels, such as the eastern gray squirrel, red squirrels, and flying squirrels, typically live in forested areas and are well-adapted to life in the trees. Ground squirrels, on the other hand, inhabit open areas like prairies, fields, and rocky terrain.

The habitat of a squirrel species plays a crucial role in determining its hibernation behaviour. Squirrels living in areas with harsh winters may be more likely to hibernate compared to those in milder climates.


 

Do All Squirrels Hibernate?


The short answer is no; not all squirrels hibernate. Most species of tree squirrels do not hibernate. Instead, they have developed other strategies to survive winter. However, many ground squirrels do hibernate. Let's explore how different squirrels live and survive during the cold winter months.


Eastern Grey Squirrels: Do They Hibernate?


Eastern grey squirrels, also known as gray squirrels, do not hibernate. These squirrels remain active throughout winter, although their activity levels may decrease. They prepare for cold weather by building warm nests, called dreys, in trees or sometimes in human homes (which can occasionally lead to the need for squirrel removal).

Grey squirrels survive winter by relying on fat reserves built up during the fall and by caching food. They spend time foraging for nuts, seeds, and other food sources, which they store in tree crevasse, buried in the ground or in attic spaces which can require squirrel removal services to get rid of. This behaviour allows them access to food even when the weather is harsh which is one reason red squirrels can be difficult to get rid of because the will wand back in the attic to access their stash of pine cones and other nuts.


Ground Squirrels and Hibernation


Unlike their tree-dwelling cousins, many ground squirrels are true hibernators. Species like the Arctic ground squirrel can hibernate for up to eight months of the year. These squirrels prepare for hibernation by eating large amounts of food in late summer and early fall to build up body fat.

When winter arrives, ground squirrels enter a state of deep sleep. Their body temperature drops significantly, and their heart rate and breathing slow down dramatically. This allows them to conserve energy and survive the cold winter months when food is scarce. They typically emerge from hibernation in late February or early March.


Tree Squirrels and Winter Survival


While tree squirrels do not hibernate, they do employ several strategies to survive winter:

1. Nesting: Tree squirrels build warm, insulated nests to stay warm during cold nights. Flying squirrels often nest in groups to share body heat.

2. Food caching: They store food in various locations to ensure a steady supply during winter.

3. Physical adaptations: Many tree squirrels grow a thicker coat to help them stay warm.

4. Behavioural changes: During extremely cold periods, they may enter a state called torpor, which helps them conserve energy.


 

Differences Between Squirrel Species


The hibernation behaviours of squirrels vary significantly between species. While most ground squirrels hibernate, tree squirrels stay active all year. The specific adaptations and behaviours also depend on the squirrel's habitat and the local climate. For example, flying squirrels, despite being tree squirrels, may enter short periods of torpor during freezing weather.


 


How Squirrels Prepare for Winter


Whether they hibernate or not, all squirrels somehow prepare for winter. This preparation typically involves:

1. Gathering food reserves: In the fall, squirrels spend more time foraging, collecting nuts, seeds, berries, and other food sources.

2. Building or improving nests: They ensure they are well-insulated and protected from the elements. City squirrels move into attic spaces and at times require squirrel removal services to evict them.

3. Increasing body fat: Squirrels eat more in the fall to build up fat reserves to help them survive the winter.


 

Squirrel Adaptations for Cold Weather


Squirrels have several adaptations that help them survive cold weather:

1. Physical changes: Many squirrels grow a thicker, more insulating coat for winter.

2. Behavioural changes: They may become less active during the coldest parts of the day.

3. Physiological changes: Some squirrels can lower their body temperature slightly to conserve energy.


 


The Role of Food in Squirrel Winter Survival


Food plays a crucial role in squirrel activity during winter, especially for species like the eastern grey squirrel. Unlike some animals that hibernate, squirrels rely on stored food to survive the colder months. These animals cache nuts, seeds, and other foods in multiple locations, ensuring they have enough resources when temperatures drop. Their ability to store food allows them to avoid the harsh weather and conserve energy, with their thick coat helping them stay warm. Squirrels have remarkable spatial memory, which helps them locate their food caches, even after snowfall, and their keen sense of smell aids in finding buried food. As they search for more food throughout winter, squirrels maintain a varied diet, including nuts, seeds, insects, and sometimes even small animals. This ability to prepare for winter and conserve energy is crucial to their survival.


 

The Impact of Climate on Squirrel Behaviour


Climate change is having a significant impact on squirrel behaviour. Milder winters in some areas are affecting the survival strategies of other squirrels, leading to changes in their activity levels. For non-hibernating squirrels, such as the eastern grey counterpart, warmer winters may offer easier access to food and reduce the need to conserve energy. However, for squirrels that hibernate, climate shifts can cause disruptions in their natural rhythms. In some cases, these changes can prevent a complete animal's body from shutting down during hibernation, leading to less efficient energy conservation over an extended period. This ultimately affects how well these animals survive through the colder months.


 

Common Myths About Squirrels and Hibernation


There are several common misconceptions about squirrels and hibernation:

1. Myth: All squirrels hibernate.

   Reality: Only some species, primarily ground squirrels, hibernate.

2. Myth: Squirrels sleep all winter.

   Reality: Most tree squirrels remain active throughout winter, albeit with reduced activity.

3. Myth: Squirrels can't survive frigid temperatures.

   Reality: Squirrels have various adaptations to survive even in freezing climates.


 

Human Influence on Squirrel Behaviour


Human activity has a significant impact on squirrel behaviour:

1. Urban environments: City-dwelling squirrels often have access to human food sources and are more active.

2. Habitat changes: Deforestation and urban expansion can affect squirrel populations and their natural behaviours.

3. Climate change: Human-induced climate change alters winter patterns, affecting squirrel behaviour.

4. Interactions with human structures: Squirrels may nest in attics or chew on electrical wires, which can lead to conflicts with humans and necessitate squirrel removal services.


 

FAQs About Squirrel Hibernation


1. Q: What happens if a squirrel doesn't gather enough food?

   A: If a non-hibernating squirrel doesn't gather enough food, it may struggle to survive the winter. However, squirrels are adaptable and may seek alternative food sources or rely more heavily on their fat reserves.

2. Q: How do squirrels find their food after snowfall?

   A: Squirrels have excellent spatial memory and a keen sense of smell, which helps them locate their food caches even under snow.

3. Q: Do baby squirrels hibernate?

   A: Baby squirrels born in late summer or early fall typically stay with their mother through their first winter and follow her hibernation or winter survival patterns.

4. Q: How long do squirrels hibernate?

   A: The duration of hibernation varies by species. Some ground squirrels may hibernate for up to 8 months, while others may only hibernate for a few weeks or months.

5. Q: Can squirrels freeze to death during winter?

   A: While it's rare, squirrels can die from extreme cold, especially if they cannot find adequate shelter or food. However, most squirrels have adaptations that help them survive even in frigid temperatures.

6. Q: How do squirrels protect themselves from predators in winter?

   A: Squirrels rely on their nests for protection and may become less active during winter to avoid predators. Their excellent climbing abilities and quick reflexes also help them evade danger.


 

Conclusion


In conclusion, while not all squirrels hibernate, these small animals have developed fascinating adaptations to survive winter. From the hibernating ground squirrels to the food-caching tree squirrels, each species has its unique way of coping with cold weather and food scarcity.

Understanding squirrels' behaviour satisfies our curiosity about these familiar backyard visitors and highlights wildlife's incredible adaptability. As we face changing climates and environments, the resilience of animals like squirrels reminds us of nature's ingenuity in facing challenges.

Whether hibernating in a burrow or scampering across snowy branches in search of cached nuts, squirrels continue to captivate us with their survival strategies and lively presence in our world. From late February, when hibernating squirrels emerge, to the cold winter months, when tree squirrels remain active, these small mammals demonstrate remarkable strategies to survive and thrive.


Wildlife Control Brampton
Wildlife Control Brampton

Recent Posts

See All
bottom of page