Squirrels are a common sight in many environments, often observed scampering up trees or digging in the ground. This behavior frequently leads to a common question about their homes: do squirrels live in burrows? While some squirrels do indeed reside underground, the answer depends on the type of squirrel, a distinction not always clear to the casual observer.
Tree Squirrel Homes
Most squirrels people commonly observe, such as grey squirrels, are tree squirrels. These animals primarily make their homes in trees, utilizing two main types of structures: dreys and tree cavities. Dreys are spherical nests constructed from interwoven twigs, leaves, and grass, often appearing as messy balls about the size of a football. Squirrels carefully line the interior with softer materials like moss, feathers, shredded bark, and pine needles to create a warm, dry haven.
These arboreal nests are built high above the ground, nestled in the forks of branches or close to the tree trunk. This elevated placement provides protection from predators and shelter from various weather conditions. Tree squirrels also inhabit natural tree cavities, hollow spaces within tree trunks. These natural dens offer insulation and protection, especially during harsh winter months and for raising young.
Ground Squirrel Homes
In contrast to their tree-dwelling relatives, a distinct group of squirrels known as ground squirrels are true burrowing animals. These species construct complex systems of tunnels and chambers beneath the earth’s surface. These underground homes serve multiple purposes, including sleeping, resting, raising their young, storing food, and providing a safe refuge from predators and extreme weather.
Ground squirrel burrows can range from 5 to 30 feet in length and reach depths of 2 to 4 feet. Individual burrow systems may feature multiple entrances and can be simple tunnels or intricate branching networks. Examples of ground squirrels include:
- California ground squirrel
- Rock squirrels
- Thirteen-lined ground squirrels
- Marmots
- Prairie dogs
- Chipmunks
When startled, ground squirrels instinctively dart into their underground burrows, a clear behavioral difference from tree squirrels that climb up trees.
Why the Confusion About Burrows?
The common misconception that all squirrels live in burrows often arises from observing tree squirrels digging in the ground. Tree squirrels frequently create small, shallow holes to bury nuts and seeds, a behavior known as caching. This food storage strategy is important for their survival, allowing them to save food for colder months when natural resources become scarce.
These holes are only an inch or two deep and about the size of a quarter, with minimal displaced soil around them. While this digging might appear to be burrowing, it is distinct from the permanent underground tunnel systems constructed by ground squirrels. Tree squirrels are simply making temporary caches for their food. Beyond caching, tree squirrels may also dig shallow depressions while foraging for roots, bulbs, or insects, further contributing to the occasional confusion.