By late summer, chipmunks are busier than ever gathering food in preparation for the coming winter. They seem less concerned with concealment and more concerned with getting the food into storage. Forsyth (1980) says that they will store about 6 litres of food which includes anything that stores well such as seeds, nuts, and plant tubers.
Chipmunks hibernate during the colder months, although this is not so much sleeping the winter away as entering a state of torpor from which they will periodically awaken in order to eat. Emerging from this torpid state would not be immediate, because their body functions slow down during this time. Banfield (1974) comments that when a chipmunk wakes from torpor “it trembles, stiffly unrolls, and staggers about, often with its eyes shut.”
Unlike red and grey squirrels, they don’t develop a thicker coat, and unlike many other animals who remain active year round, they do not fatten up for the winter. All their energy goes into ensuring their larder is full so that they can eat during the winter without having to expend valuable energy searching for food. On particularly warm winter days, you may even see the occasional chipmunk roaming around the garden, but this is by no means common.
You might think that being deep underground would guarantee safety, but weasels are known to enter chipmunk burrows and kill the animals, which would be very easy prey, particularly if still in torpor. Whether the short-tailed weasel we had around the garden a few years back ever did this is not known, but my guess would be that such a clever animal would make full use of all food sources!
By about mid-March, particularly if the winter has been fairly mild, we can expect to see chipmunks once again scampering around the FWG.
Photo: D. Gordon E. Robertson