Squirrels are familiar backyard visitors, known for their agile movements and bushy tails. While their fondness for nuts is widely recognized, their natural diet is considerably more diverse than many realize. This article explores what squirrels eat, what foods are harmful, and how they secure their meals.
Wild Diet
Squirrels are omnivorous, primarily consuming plant-based foods. Their diet includes various nuts like acorns, walnuts, hickory nuts, pecans, hazelnuts, and pine nuts. They also eat seeds from sunflowers, maples, and pine cones, often in their shells, which helps keep their continually growing teeth healthy.
Beyond nuts and seeds, squirrels forage for fruits and berries, including apples, grapes, cherries, blueberries, blackberries, and strawberries. They also eat tree buds, flowers, and bark. Mushrooms and other fungi provide additional nutrients. Occasionally, squirrels supplement their diet with protein from insects like grubs and caterpillars, and rarely, bird eggs or small nestlings, showcasing their opportunistic nature.
Harmful Foods
Many common human foods are detrimental to squirrel health. Processed items like bread, crackers, and pastries offer minimal nutritional value and can cause digestive issues or malnourishment. Foods high in salt, such as chips and pretzels, can lead to dehydration and kidney problems. Items rich in sugar, including candy and chocolate, can cause dental problems, obesity, and metabolic imbalances.
Chocolate is particularly toxic to squirrels due to theobromine, a stimulant they cannot metabolize, leading to tremors, elevated heart rate, seizures, or even death. Peanuts are legumes, not true nuts, offering poor nutritional value; raw peanuts can also contain harmful aflatoxins. Dried corn, if left out, can develop mold containing aflatoxins, and overreliance on corn leads to nutritional deficiencies. Dairy products are unsuitable, as squirrels are lactose intolerant. Avocado pits and skin contain persin, a substance toxic to many animals.
Foraging and Storing Food
Squirrels locate and secure food using a keen sense of smell, spatial memory, and visual cues to find buried caches and assess quality. This foraging behavior is especially pronounced in autumn when they collect and bury nuts and seeds for leaner months.
Their primary storage method is “scatter hoarding,” burying individual food items in numerous shallow holes across their territory. This strategy ensures a distributed food supply and reduces the risk of losing an entire cache to competitors or spoiling. Squirrels sometimes engage in deceptive caching, pretending to bury food when observed by others to protect actual stashes. Caching is intense as nuts mature, with recovery increasing when other food sources become scarce.
Hydration Needs
Water is an indispensable component for a squirrel’s survival. They obtain it from various natural sources, including puddles, streams, rivers, and dew on leaves and grass. They also extract moisture directly from foods such as fruits and vegetables.
Despite deriving water from food, squirrels actively seek out water sources, especially during hot, dry periods or when nursing young. Providing a shallow dish of fresh water can ensure they have access to hydration when natural sources are limited.