The common question of whether red squirrels reside underground stems from confusion with other small, burrowing rodents. Red squirrels, including the Eurasian red squirrel (Sciurus vulgaris) and the American red squirrel (Tamiasciurus hudsonicus), are classified as arboreal, meaning they are tree-dwelling mammals. They spend the majority of their lives utilizing the forest canopy, which serves as their primary domain for shelter, safety, and diet. While they interact with the forest floor, their permanent homes and nesting sites are almost exclusively located high above the ground, distinguishing them from true ground squirrels or chipmunks.
Primary Residence in the Canopy
Red squirrels possess physical traits that make the intricate network of tree branches their ideal environment. Their agility is supported by specialized anatomy, including double-jointed ankles that allow their hind feet to rotate backward. This flexibility enables them to rapidly descend tree trunks headfirst. Sharp, curved claws further enhance their grip, allowing them to traverse branches and bark surfaces with speed and confidence.
The bushy tail functions as a dynamic counterbalance. This appendage helps the animal maintain stability while leaping and navigating gaps between trees, acting like a rudder and a balancing pole. Their reliance on the canopy provides a natural defense against many terrestrial predators, making the trees a safer place to rest, travel, and observe their territory.
Building and Using Nest Structures
Instead of digging burrows, red squirrels construct complex nests called dreys, which are located securely within the trees. A drey is a spherical structure, roughly the size of a football, typically found in a fork of branches or wedged into dense conifer branches. The outer shell is constructed from interwoven twigs and leaves, providing a sturdy framework.
Inside this protective shell, the squirrel creates a soft, insulated core by lining the cavity with materials like moss, dried grass, shredded bark, and hair. This lining provides warmth and shelter from inclement weather and cold temperatures, especially since red squirrels do not hibernate.
Dreys serve multiple purposes, functioning as a safe sleeping spot, a retreat during the day, and a natal site for raising young, called kits. A single squirrel often maintains several dreys within its territory. They rotate between them to avoid the build-up of parasites or to utilize more weatherproof shelter, such as an existing tree cavity, during winter.
Ground Foraging and Temporary Use of the Forest Floor
Red squirrels are frequently observed on the forest floor, which is the source of the misconception that they live underground. This terrestrial activity is driven by the need to acquire and store food resources. They descend to the ground to collect nuts, seeds, fungi, and conifer cones, which are then consumed or transported.
The American red squirrel is known for a caching strategy called larder-hoarding, where they create a central stockpile of food, known as a midden. These middens are large piles of cones and debris, often located at the base of a tree or under a log. The moist environment of the midden helps keep conifer cones from opening, preserving the seeds for later consumption.
Even when burying individual items, a practice known as scatter-hoarding, the squirrel’s time on the ground is dedicated to resource acquisition. They quickly retreat to the safety of the trees or their elevated dreys for permanent rest and shelter, using the ground only as a necessary workplace.