| Gray-footed chipmunks are shy and more often heard than seen. They make light "chipper" or low "chuck-chuck-chuck" calls, and when they sense danger, they scurry into deep brush, or underground, or up a tree. They are agile climbers, easily navigating rocks, cliffs, and trees. Acorns are probably their most important food during late summer and fall. They do not get tremendously fat in the fall, as do most animals that hibernate, so they probably feed on stored food.
Males are slightly larger than females.
Bailey, V., 1902. Seven new mammals from western Texas, p. 117. Proceedings of the Biological Society of Washington, 15:117-120.
Mammal Species of the World
Mammalian Species, American Society of Mammalogists' species account
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