Squirrels are common animals, and their behaviors during the colder months often spark curiosity. As winter approaches, these agile creatures employ adaptations to endure challenging conditions. Understanding where they reside and how they manage through the cold offers a glimpse into their remarkable resilience.
Winter Homes of Squirrels
Squirrels primarily utilize a few types of shelters for winter, each offering varying levels of protection. Tree squirrels, such as grey and fox squirrels, frequently construct nests known as dreys. These spherical structures, often 12 inches or more in diameter, are typically built from twigs, dry leaves, and grass, usually assembled in the forks of tall trees or close to the trunk. Dreys provide insulation against the elements, with an inner lining of finer materials like moss, shredded bark, or pine needles for added warmth.
Beyond dreys, squirrels also seek refuge in natural tree cavities or dens. These are often existing holes in trees, sometimes abandoned by woodpeckers, offering superior protection from predators and harsh weather due to their secure, enclosed nature. These cavities are also lined with insulating materials to create a cozy interior. Ground squirrels, unlike their arboreal counterparts, spend winter in underground burrows, which they inhabit year-round. These burrows can extend several feet deep, providing a stable environment below the frost line.
How Squirrels Prepare for Winter
Squirrels undertake several proactive measures as autumn transitions into winter to enhance their survival prospects. A significant activity is food caching, where they bury or hide nuts, seeds, and other food items. This behavior ensures they have access to nutrition when natural food sources become scarce. Some species engage in “scatter hoarding,” burying individual items across many locations, while others may create central caches.
Another preparation involves building new dreys or reinforcing existing ones with additional insulating materials. This reinforcement helps to create a warmer, more secure shelter for the impending cold. Physiologically, squirrels also undergo changes, developing a thicker winter coat for improved insulation. They also increase their body fat reserves during the fall, which serves as a crucial energy source when food is limited.
Beyond the Den: Winter Survival Strategies
During the winter months, squirrels adapt their behavior to conserve energy and find sustenance. While they do not truly hibernate, squirrels significantly reduce their activity levels, spending more time sleeping in their nests during severe cold spells. This reduced activity minimizes their need for constant foraging.
Squirrels may enter a state of torpor, which is a temporary decrease in physiological activity, including a lowered body temperature, heart rate, and metabolism. This allows them to conserve energy during very cold periods, though they can easily awaken from this state. On warmer winter days, squirrels venture out of their dens to retrieve cached food, relying on both memory and their acute sense of smell to locate buried provisions, even under snow. To further conserve warmth, multiple squirrels sometimes share a drey or tree cavity, huddling together to share body heat.
Common Misconceptions About Squirrels in Winter
Many people hold misunderstandings about how squirrels manage through winter. A common belief is that tree squirrels hibernate, but this is inaccurate; most common tree squirrels, like grey squirrels, remain active throughout the winter, albeit with reduced activity. Instead of true hibernation, they engage in torpor, a short-term state of decreased metabolism.
Another misconception relates to their ability to find cached food. While they possess an impressive spatial memory, squirrels also heavily rely on their keen sense of smell to locate buried nuts and seeds, especially when visual cues are obscured by snow. They do not simply “remember” every single hidden item. Despite their remarkable adaptations, winter remains a challenging period for squirrels, and not all individuals survive the harsh conditions. Their strategies enhance survival, but the season still presents significant difficulties.