Chipmunk is the common name for any small squirrel-like rodent. About 23 species fall under this title, with one species in northeastern Asia. They are also in the eastern portions of Canada and the US. The rest are native to the western part of North America.

Eastern chipmunks mate in early spring and again in early summer to produce two litters. Each have four to five young, but western chipmunks only breed once a year. The young emerge from the burrow after about six weeks and strike out on their own within the next two weeks.

Chipmunks are commonly depicted with their paws up to the mouth, eating peanuts, or more famously their cheeks bulging out on either side, however they eat a much more diverse range of foods than just nuts. Their omnivorous diet consists of grain, nuts, birds’ eggs, fungi, worms, and insects. Come autumn, many species of chipmunk begin to stockpile these goods in their burrows. Other species make multiple small collections of food. These two kinds of behavior are called larder hoarding and scatter hoarding. Larder hoarders usually live in their nests until spring.

These small squirrels fulfill several important functions in forest ecosystems. Their activities with regards to harvesting and hoarding tree seeds play a crucial role in seedling establishment. They also consume many different kinds of fungi.

Chipmunks play an important role as prey for various predatory mammals and birds. They are also opportunistic predators themselves, particularly with regard to bird eggs and nestlings.

Chipmunks construct expansive burrows, which can be more than 3.82 yards (3.5 m) long. The burrows have several well-concealed entrances. The sleeping quarters are kept extremely clean, as shells and feces are stored in refuse tunnels.

If unmolested they often become bold enough to take food from the hands of humans.