They feed on a great variety of things, such as nuts, seeds, fungi, fruits, and the cambium layer of tree bark, as well as bones and turtle shells. They store nuts and acorns in holes in the ground. Gray squirrels mate in January - February and July in the north, December and June in the south. They make a variety of calls, including the familiar clucking and fussing calls. Most squirrels are sedentary, however, spending their entire lives within a single acre of land.
Guard hairs protect the fur, while the fur insulates the mammal.
The large quantity of nuts translated into a huge population of squirrels, which devastated the crops and plagued the colonists.