Squirrels are often perceived as strictly vegetarian, focused only on nuts and seeds. However, this common perception does not tell the whole story of their foraging behavior. The question of whether these familiar rodents consume earthworms reveals a more complex reality about their survival strategies.
Squirrels as Opportunistic Omnivores
Squirrels are classified as omnivores, consuming both plant and animal material for sustenance. While they do not actively hunt large prey, they take advantage of nearly any available food source to meet their nutritional requirements. This opportunistic feeding habit explains why an earthworm might occasionally end up on a squirrel’s menu.
The consumption of animal matter is driven by a need for concentrated fats and protein. This need is more pronounced when primary food sources are scarce or during periods of high physical demand, such as gestation. Ground squirrels are more likely to encounter and consume earthworms than their arboreal relatives.
The Staple Diet of Tree Squirrels
Despite their omnivorous capacity, the vast majority of a tree squirrel’s caloric intake comes from plant-based foods. Their diet is overwhelmingly composed of nuts and seeds, such as acorns, hickory nuts, and pecans, which provide the high levels of fat necessary for energy storage. These items are often cached for later use, allowing them to survive periods when fresh food is unavailable.
Squirrels also feed on a variety of other plant materials depending on the season. They consume fungi, including mushrooms and truffles, and graze on tree buds, flowers, and fruits. In the spring, they may strip the cambium layer from tree bark to access sugars and minerals.
Other Unexpected Protein Sources
Earthworms are one example of the animal protein squirrels opportunistically consume. Their flexible diet extends to a wide array of invertebrates and smaller vertebrates to supplement their primary diet. This includes insects like caterpillars and beetles, which are easily foraged and provide a valuable source of fat and protein.
Squirrels have also been observed raiding bird nests to consume eggs and nestlings. They will eat carrion or even small vertebrates like mice or lizards if the opportunity arises, particularly among ground squirrel species. These protein-rich meals are a crucial part of their survival strategy.