The question of whether a squirrel returns to the same nest is common, as their homes appear to be temporary structures. These nests, technically called dreys, are intricate, spherical shelters built high in the trees from interwoven twigs and leaves. Squirrels are highly adaptable creatures found in diverse environments, requiring flexible dwelling strategies. Understanding the nature of the drey helps answer the question of nest fidelity, which is a key part of the animal’s survival strategy.
The Habit of Reuse
Squirrels, particularly common species like the Eastern Gray Squirrel, reuse their established nests. An individual maintains a defined home range containing several usable dreys and den sites. They prefer maintaining these existing structures, repairing and relining them if they remain structurally sound, even across multiple breeding seasons.
Reuse is rarely continuous, as the squirrel often rotates through its available dwelling options. Returning to a known, stable shelter is far more common than staying in a single nest indefinitely. These additional nests function as rest stops during foraging, emergency shelters from a sudden threat, or temporary homes throughout the year. Squirrels build multiple dreys within their territory to ensure they have options when needed.
Why Squirrels Maintain Multiple Dreys
The primary reason a squirrel maintains a network of dreys is to manage parasites. Continuous occupation of a single nest allows ectoparasites like fleas, mites, and ticks to build up to uninhabitable levels. By rotating homes frequently, the squirrel leaves the infested structure, giving the parasite population time to decline before a potential return.
Another reason for maintaining multiple shelters is predator evasion. Using various locations makes a squirrel’s sleeping spot less predictable to predators such as raccoons or snakes. If a predator learns the location of one nest, the squirrel can immediately relocate to a different, pre-built structure. This minimizes the scent trail and avoids establishing a predictable pattern of residency.
Multiple dreys also serve as emergency backups against environmental damage. A strong windstorm or heavy downpour can compromise the integrity of a leaf nest. If one drey is damaged, the squirrel can move its family to another fully functional shelter immediately. This network ensures the animal is never left without a secure place to rest or raise its young.
Seasonal Shifts and Specialized Dwellings
Seasonal needs dictate the type of dwelling that is reused. During warmer spring and summer months, squirrels construct simpler, more open leaf nests known as summer dreys. These structures are used primarily for quick shelter and resting, and they are generally less dense and easier to build than their winter counterparts.
When colder weather arrives, the need for insulation causes a shift in dwelling preference. Squirrels seek out pre-existing tree cavities, often called dens, which offer protection from wind, snow, and rain. These natural hollows are reused across years due to their stability and insulating properties. If a tree cavity is unavailable, the squirrel constructs a bulkier, more densely packed drey specifically for winter use.
Female squirrels utilize specialized maternal nests, which are the most secure and insulated structures available. These are typically tree cavities, as litters born in dreys are vulnerable to predator attacks. The female requires this secure location for the 10 to 12 weeks it takes to raise the young, and if the site remains safe, it will likely be reused for subsequent litters.