What Do Chipmunks Eat? Seeds, Nuts and Cheek Pouch Facts

What does a chipmunk eat in the wild?

The eastern chipmunk is a forager of the forest floor. It spends most of its active day searching for food on the ground and climbs trees and shrubs when nuts or fruit are ripening above.

Its main foods change through the seasons:

Seeds and nuts are the core of the diet all year, because they are rich in energy and keep well underground. Spring can be a difficult time: the winter stores are running low and few new seeds are available. Trees that drop seeds early, such as red maple, are especially important then.

Do chipmunks eat meat and insects?

Yes, in modest amounts. Chipmunks eat insects and their larvae, earthworms, slugs, snails and other invertebrates, particularly in spring and summer when they are easy to find. Animal food provides protein, which is useful for growing young and for breeding females.

Chipmunks are also opportunistic predators of bird nests. They take eggs and sometimes nestlings of ground-nesting and shrub-nesting songbirds, and they occasionally catch small frogs or very small snakes. These are exceptions, not the main diet.

Fungi are another important food. Chipmunks eat many kinds of mushrooms and underground fungi, and they spread the fungal spores in their droppings around the forest.

How do chipmunk cheek pouches work?

Chipmunks have two large cheek pouches, one on each side of the mouth, made of thin, stretchy skin. A foraging chipmunk picks up seeds or nuts with its front paws, often removes husks or sharp edges with its teeth, and pushes the food into the pouches.

Full pouches can make the head look about twice as wide as normal. Observers have reported single chipmunks carrying around 70 small sunflower seeds at once, while larger items such as acorns fit only a few at a time. Back at the burrow, the chipmunk pushes the food out with its paws.

Pouches let a chipmunk gather a lot of food quickly and then carry it to safety, instead of eating in the open where hawks, foxes and cats can catch it. A busy chipmunk may make many trips in a single autumn day.

How do chipmunks store food for winter?

Eastern chipmunks are mainly larder hoarders. They keep most of their food in one or more storage chambers inside the burrow, sometimes under the nest itself. A well-stocked larder can contain hundreds or even thousands of seeds and nuts.

They also practice some scatter hoarding, burying small caches of seeds just under the soil around their home range. Chipmunks can relocate many of these caches, but some are forgotten or never needed, and those seeds may sprout into new plants.

Hoarding starts in summer but is most intense in early autumn, when nuts and seeds ripen. A large larder matters a great deal, because eastern chipmunks do not build up thick fat reserves. Instead, they wake from winter torpor every few days and eat from their stores. For more, see do chipmunks hibernate?

Chipmunks vs squirrels: how their diets compare

Chipmunks and tree squirrels eat many of the same foods, but they store them in different ways.

• Eastern chipmunks carry food in cheek pouches and keep most of it in a protected underground larder.
• Eastern gray squirrels have no cheek pouches. They carry one nut at a time in the mouth and bury nuts one by one in hundreds of separate spots; see do squirrels remember where they bury nuts?
• Red squirrels in North America pile cones in large middens near their trees.

For the full squirrel menu, read what squirrels eat.

Myths and facts about chipmunk food

Myth: chipmunks only eat nuts. Nuts are important, but chipmunks also eat seeds, fruit, fungi, flowers, insects, worms and even the occasional egg.

Myth: chipmunks carry soil in their cheek pouches when digging. The pouches are used for food and sometimes nest material. Chipmunks scatter excavated soil with their feet or use it to plug old tunnels.

Fact: chipmunks are messy eaters in a useful way. Seeds dropped, buried and forgotten by chipmunks help some trees and plants spread through the forest.

Watching a chipmunk fill its cheeks on a woodland trail is a fine way to see this behavior. Wildlife experts generally advise against feeding wild animals, so the best view is of chipmunks finding their own natural foods.