Squirrels, familiar inhabitants of many landscapes, construct shelters, known as dreys, throughout the year. These structures provide protection from predators and the elements, and safe havens for raising their young. Squirrels do not hibernate, remaining active even in colder months, which makes their nests continuously important for survival.
Identifying a Squirrel Drey
A squirrel drey typically appears as a bulky, spherical, or oval-shaped mass of interwoven materials, often resembling a large, untidy ball of leaves high in a tree. These structures commonly measure about 1 to 2 feet in diameter, though some can be larger. The outer layer of a drey is primarily constructed from a robust framework of twigs, leafy branches, and bark, tightly woven to form a protective shell. This external layer helps insulate the interior from wind and water, providing a degree of weather resistance.
Squirrels often begin by weaving a platform of gnawed green twigs, allowing the leaves to remain attached and contribute to the structure as they dry. Inside this tough exterior, a drey features a soft, insulated inner lining. This cozy core is typically composed of finer materials such as grass, moss, shredded bark, pine needles, fur, or feathers. The entrance to a drey is usually a small, inconspicuous hole, often oriented towards the tree trunk to help keep rain out.
Understanding Cavity Nests
Beyond the visible dreys, squirrels also utilize cavity nests, built within existing hollow spaces. These nests are commonly found inside tree hollows, abandoned woodpecker holes, or natural crevices within tree trunks and large branches. Unlike dreys, cavity nests lack an external structure of woven materials because they are contained within an enclosed space. This concealment offers protection from predators and provides superior insulation, particularly during colder periods.
The construction of a cavity nest focuses on creating a comfortable and insulated interior. Squirrels line these cavities with a variety of soft, warm materials, including shredded bark, dried leaves, grass, moss, animal fur, or feathers. In urban settings, squirrels might also incorporate human-made insulation materials if they access structures. The presence of a cavity nest is often indicated by observing squirrels frequently entering and exiting a hole or opening in a tree or structure.
Where Squirrel Nests Are Found
Squirrels place nests in locations offering stability and protection. Dreys are typically constructed high in tree branches, often nestled securely in the fork of two strong branches or tightly against the tree trunk. This elevated placement, usually 20 feet or more above the ground, deters ground predators and provides a stable foundation for the structure. Trees that offer abundant food sources, like oak trees, are frequently chosen for drey construction.
Cavity nests are situated within natural or pre-existing hollows, such as hollowed-out tree trunks, large branches, or old woodpecker holes. These natural dens are often preferred for winter use due to their superior warmth and protection. In urban and suburban environments, squirrels may adapt to human structures, creating cavity nests in attics, wall voids, chimneys, or even abandoned birdhouses.