The common perception of a squirrel focused solely on burying nuts often leads to the belief that it is an herbivore. This view overlooks the complex and adaptable nature of the squirrel’s diet, which is designed to sustain it across varying seasons and environments. Understanding a squirrel’s complete dietary profile reveals that its feeding habits are far more diverse than simply consuming acorns and seeds.
The Core Classification: Squirrels as Omnivores
Animals are categorized into three main feeding groups: herbivores eat only plant matter, carnivores consume only animal matter, and omnivores eat both. The squirrel, with its highly varied menu, is definitively classified as an omnivore. This classification is based on their capability to derive nutrition from both sources, not the quantity of meat versus plants they consume. While plant-based foods make up the majority of their caloric intake, the inclusion of animal matter is a consistent part of their foraging strategy. This adaptability allows squirrels to sustain high energy levels throughout the year, even when preferred plant foods are scarce.
The Herbivorous Side of the Squirrel Diet
The most visible component of the squirrel’s diet is the extensive range of plant matter it consumes, which provides the bulk of its daily energy and carbohydrates. Nuts and seeds, particularly high-energy varieties like hickory nuts, walnuts, and acorns, are primary staples, especially in the autumn. The act of burying these items, known as scatter hoarding, ensures a food supply for the leaner winter months. Depending on seasonal availability, squirrels consume various other plant parts, including nutrient-rich tree buds, flowers, and shoots in the spring, and fruits and berries in the summer. Fungi, such as mushrooms and truffles, are also consumed for important minerals, and when resources are scarce, squirrels gnaw on tree bark to obtain sodium.
The Carnivorous Side of the Squirrel Diet and Foraging Behavior
The consumption of animal matter, though a smaller percentage of the overall diet, is a necessary practice. This protein and fat intake is particularly important for reproductive health in pregnant or nursing females. Squirrels are opportunistic predators and scavengers, taking advantage of easily accessible animal food sources.
Animal Prey and Scavenging
Insects, such as beetles, grubs, grasshoppers, and ant larvae, are regularly hunted and consumed. A more surprising part of their diet involves vertebrate prey, which they seek out when they need extra nutrients. Squirrels have been documented raiding bird nests to eat eggs and defenseless nestlings. They will also opportunistically consume small mammals, such as mice or shrews, and occasionally scavenge carrion or gnaw on bones. This bone chewing is thought to be a method for obtaining calcium and other minerals that may be lacking in their plant-heavy diet.
This “scatter hoarding” strategy ensures a variety of food types are available, allowing them to balance their intake of high-energy nuts and protein-rich animal matter throughout the year.