Many people assume squirrels eat only plant material, often seeing them bury nuts. However, squirrels are omnivores, meaning they naturally consume both plant and animal matter. This flexible diet allows them to adapt to various food sources, contributing to their widespread success across diverse habitats.
Primarily Plant-Based Foraging
Squirrels primarily forage for plant-based foods, which constitute a large portion of their diet. They consume nuts such as acorns, walnuts, and pecans, providing essential fats and proteins. Seeds, including sunflower and pumpkin seeds, are also a favored food source, offering concentrated energy and important nutrients like fiber, vitamin E, calcium, magnesium, phosphorus, and iron.
During spring and summer, their diet expands to include fresh plant materials. Squirrels feast on tender buds, new shoots, leaves, flowers, and fruits like berries and cherries, which provide hydration, carbohydrates, and vitamins. They also consume fungi like mushrooms, offering proteins and minerals, and even tree bark and sap, especially during leaner times.
The Role of Animal Matter in Their Diet
While plant matter forms the bulk of their diet, squirrels regularly supplement it with animal matter. This provides crucial protein, fats, and other nutrients not always abundant in plant sources. They consume insects such as caterpillars, grasshoppers, and beetle larvae, especially when fruits and nuts are scarce. These insect sources are rich in protein, vital for growth and energy.
Squirrels also prey on bird eggs and nestlings, raiding nests when opportunities arise. This behavior offers a concentrated source of protein and fat. Some species, like flying squirrels, may occasionally eat small mammals or carrion. Female squirrels, especially when pregnant or nursing, often seek out animal protein to meet their increased nutritional demands.
Why a Varied Diet is Key to Survival
The omnivorous nature of squirrels is a significant factor in their ability to thrive across diverse environments. Their dietary flexibility allows them to adapt to seasonal changes in food availability, ensuring year-round sustenance. For instance, they shift from fresh plant-based foods in warmer months to stored nuts and seeds, supplementing with tree bark, fungi, or animal matter in winter. This varied diet provides a comprehensive range of nutrients, including carbohydrates, fats, and proteins.
Their opportunistic feeding strategy means they can exploit whatever food sources are available, reducing reliance on a single type of food. This adaptability contributes to their resilience, allowing them to maintain health and sustain populations even when preferred food items are scarce. By consuming both plant and animal matter, squirrels obtain all necessary vitamins, minerals, and macronutrients, supporting their active lifestyles.