A Natural History Of The Squirrel. Squirrels are common throughout North America. They build their nests high in the trees from twigs and leaves, or they nest in a hollow of an old tree. They are not above trying to move into a good-sized bird house or even an occasional attic. The most common squirrels found in the Carolinas are the common gray squirrel and the flying squirrel.
Gray squirrels are diurnal, meaning they are most active during daylight.
Their natural diet includes nuts, berries, mushrooms, insects, buds, leaves, bark off trees, fungi, grasses, and pine cones. Flying squirrels are nocturnal, so it's not very often that you're fortunate enough to see them. They are able to fly due to a loose flap of skin between the front and rear legs that they spread as they glide from tree to tree. Flying squirrels prefer natural tree cavities or abandoned woodpecker holes for their homes. Their diet is similar to that of the gray squirrel, with an occasional small bird for variety.