Plant matter:
* Nuts: Acorns, walnuts, pecans, hazelnuts, beechnuts, pine nuts, etc.
* Seeds: Sunflower seeds, pumpkin seeds, birdseed, etc.
* Fruits: Apples, pears, berries, peaches, etc.
* Mushrooms
* Bark: Especially in winter when other food sources are scarce.
* Buds: They also eat buds from trees, especially in the spring.
* Grasses: They eat grasses and other vegetation, especially in the spring and summer.
Animal matter:
* Insects: Squirrels will catch and eat insects, especially when young.
* Small vertebrates: Some squirrels may prey on small animals like birds, mice, and lizards.
* Eggs: They will also eat bird eggs, although this is less common.
Specific to different squirrel species:
* Tree squirrels: Mostly eat nuts, seeds, fruits, and mushrooms.
* Ground squirrels: Eat more insects, grasses, and seeds.
* Flying squirrels: Their diet is similar to tree squirrels, but they may also eat more insects.
Important factors:
* Season: In the fall, squirrels gather nuts and seeds to bury for the winter. During the winter, they rely on these stored foods, as well as bark, buds, and other less desirable food sources.
* Availability: Squirrels will eat whatever is readily available in their environment.
* Location: The diet of squirrels can vary depending on where they live.
It's important to remember that feeding squirrels can be detrimental to their health and the ecosystem. They can become reliant on human food sources, which can lead to malnutrition and a decrease in their natural foraging skills.