Squirrels require safe places to rest and sleep. These adaptable creatures are resourceful in finding or constructing shelter, allowing them to thrive in diverse environments.
Squirrel Nests and Dens
Squirrels primarily use two types of structures for sleeping: dreys and tree cavities. A drey is a nest built by a squirrel, a spherical or messy ball of interwoven twigs and leaves. These structures are usually about the size of a football, with an outer shell of woven twigs and an inner lining of softer materials.
A tree cavity, or den, is a natural hollow within a tree trunk or large branch. These dens can be existing holes that squirrels adapt for their use. Tree cavities offer a more enclosed and robust shelter than dreys.
Choosing and Building a Home
Squirrels select locations for their homes, often high in trees, typically at least six meters (20 feet) above ground. These sites, often in sturdy branch forks or close to the tree trunk, provide stability and protection. Squirrels can also nest in human structures like attics, seeking warmth and seclusion.
For dreys, squirrels weave twigs to form a platform. They pack damp leaves and moss onto this base to reinforce the structure, creating a spherical outer shell. The interior is lined with soft materials like shredded bark, grass, moss, feathers, pine needles, and their own fur, ensuring a comfortable, insulated space.
Tree cavities are also lined with similar materials for comfort and insulation. Squirrels may gnaw at a cavity’s entrance to widen it, customizing their den. The criteria for selecting a home prioritize protection from predators and harsh weather conditions.
Seasonal Sleeping Habits
Squirrels adapt their sleeping habits and choice of shelter throughout the year to contend with changing environmental conditions. During warmer summer months, squirrels may use lighter, more open dreys, which provide adequate protection without excessive insulation. As colder weather approaches, squirrels often transition to more insulated dreys or seek the superior protection of tree cavities. Tree cavities offer better insulation and protection from wind and rain.
While some ground squirrel species may enter a deep sleep state similar to hibernation, most tree squirrels do not truly hibernate. Instead, they may enter a state known as torpor during periods of extreme cold. Torpor involves a temporary reduction in body temperature, heart rate, and metabolic activity, allowing them to conserve energy. Squirrels periodically awaken from torpor to forage for their cached food supplies before returning to their sheltered nests.