Tuesday, December 29, 2015

The Lives Of Chipmunks In Winter

While many people consider chipmunks pests, they are one of our more endearing squirrels. I suspect that part of their charm comes from the fact that we don’t see them for almost half of the year. Contrary to popular belief, though, chipmunks don’t hibernate the winter away, not really. Unlike true hibernators, who sink so deeply into a comatose state that it takes a bit of doing to wake them up, chipmunks could be considered light sleepers.

A true hibernator spends the summer and fall seeking out all possible food items and eating them. The goal is to put on as much fat as possible, for once the big sleep hits, the animal must live off its stored energy supply. If it doesn’t get enough food before winter, the animal is likely to starve to death, never waking to see the blush of dawn on a new spring morning.

The eastern chipmunk (Tamias striatus) however, spends its summer and fall collecting food and storing it away for later consumption. No gluttonous feeding for our small striped friend. Nope, the chipmunk is a hoarder. Deep in its tunnel (which can be up to thirty feet long, with many entrances and exits), chambers are stuffed with the seasons’ harvest: beechnuts (their favorite), maple seeds, sunflower seeds (when bird feeders are near), and more. Although the chipmunk’s diet is quite varied (seeds, nuts, berries, fungi, invertebrates), the winter food supply is made up of hard foods only (nuts, some seeds), because these are less likely to go bad over the many weeks of subterranean storage. And, just in case you were wondering, chipmunks have been discovered with up to eight pounds of food cached away for the winter.

Chipmunks are not ones to put all their proverbial eggs in one basket, though. On the off chance that something happens to the food stored so carefully within the burrow, chipmunks hedge their bets by scatter hoarding, caching stockpiles of food in various locations. Sometimes these stashes are discovered by other foragers, and other times entirely forgotten. This shouldn’t be considered a waste of resources though, for any foods not eaten will either eventually decompose, providing nourishment for the soil and nearby plants, or sprout and grow into future oaks, beeches and maples.

Every fall I take note of how late in the season I see chipmunks. If winter comes early, they disappear quickly. This year, however, autumn seemed to hang around forever, and with it chipmunks were seen gathering seeds as late in the season as possible. Now that the ground is blanketed in white though, and temperatures plunge steadily below freezing, we won’t see hide nor hair of a chipmunk for months. Red squirrels will continue to make pests of themselves at the bird feeders, but chipmunks are conspicuous only by their absence. Until a thaw comes. There have been a few times when mild days in February or March have brought the chipmunks out of their cozy dens to forage for some fresh seed on the snow banks below the bird feeders. It’s always exciting to see their little striped bodies as they flit across the snow, cheeks stuffed with sunflower seeds.

Eventually spring will arrive, and with it the chipmunks come, ready to eat. Everything that is available is fair game. In many cases, this may be the seed from bird feeders, but it could also be fungi, buds, or nuts and seeds not already consumed during the winter. And it’s not unheard of for a chipmunk to eat the eggs of small birds, or even a nestling or two. Food is food, and in the animal world it’s all fair game.

Photo by Charlotte Demers, Adirondack Ecological Center, Newcomb, NY.

A version of this story was first published in the Adirondack Almanack in 2009.


Ellen Rathbone

Ellen Rathbone is by her own admission a “certified nature nut.” She began contributing to the Adirondack Almanack while living in Newcomb, when she was an environmental educator for the Adirondack Park Agency’s Visitor Interpretive Centers for nearly ten years.

Ellen graduated from SUNY ESF in 1988 with a BS in forestry and biology and has worked as a naturalist in New York, New Jersey, and Vermont.

In 2010 her work took her to Michigan, where she currently resides and serves as Education Director of the Dahlem Conservancy just outside Jackson, Michigan.

She also writes her own blog about her Michigan adventures.





One Response

  1. Lpbob3 says:

    Always love watching chipmunks, thanks for the info!