How would you describe a chipmunk? Adorable? Greedy? What about cunning survivalist? No matter what attitude you might have about these ground squirrels, they have developed impressive ways to deal with winter. We won’t see much of them in the approaching months, as winters are spent below the frost line, where they employ these savvy survival strategies.
1) There’s room for renovation.
You’ve likely seen the “front door” of a chipmunk’s underground burrow. Eastern forest floors are dotted with 1 ½ – 2 inch holes, which are usually the humble openings to a chipmunk’s complex system of tunnels and chambers. These underground dens can be up to 30 feet in length, and as time goes on, many rooms are created to serve different domestic purposes. There are separate “rooms” for sleeping, for waste, and for storing food. The basic bedroom, bathroom, and kitchen are covered, with more chambers added throughout a chipmunk’s life. When more space is required, chipmunks can simply dig, and remove soil from the burrow using their specialized cheek pouches.
2) Chipmunks have an escape route.
Chipmunks can hide their entrance holes under logs and rocks, but unfortunately, they cannot hide their scent. Predators such as weasels can enter their burrows even in winter. In defense, chipmunks build a few “dummy” tunnels that lead to dead ends, which can confuse predators and buy time for chipmunks to escape. Another sneaky strategy chipmunks use is to build several exit holes that connect to tunnels in different ways, making their burrow somewhat of a maze.
3) A well stocked pantry.
These rodents do not truly hibernate, but they do spend many cold winter days in a slowed metabolic state. Instead of storing a lot of extra fat, they arise periodically to eat throughout the winter. So chipmunks must cache an incredible amount of food. Some estimate they store up to 4 gallons of seeds, fruit, and fungi! All for a creature weighing around 3 ounces. How do they store this large amount of food? This is another use for their special cheek pouches! Chipmunks can cause frustration to those who feed birds, as they can carry away lots of seed in a short amount of time. Chipmunks have been observed packing their pouches with 70 sunflower seeds in one visit to a bird feeder!
4) They have insurance.
If you haven’t already decided that chipmunks have a pretty good plan for winter, rest assured they would be fine even if robbed. That’s right, if another animal finds their stash of 6,000 nuts, they have an emergency food cache in a separate burrow dug somewhere else. In fact, chipmunks have several emergency caches. How does your winter storm power outage plan measure up to this?
5) A productive solution to cabin fever.
In February and March, with spring rains on the way, chipmunks venture away from their burrows to breed. They are solitary creatures except during breeding season and when raising their young. The underground burrow offers an ideal place to raise young chipmunks, which are naked and blind when born. They spend their first month underground in the burrow, emerging almost fully independent.
In recent years, evidence shows chipmunk behavior has changed in response to the warmer winters. So you may see chipmunks staying active throughout the winter. Hopefully they can adapt well to the changes and maintain seasonal survival techniques. – Colleen Sharkey
For more information on these fascinating creatures see the Encyclopedia of Life: Eastern Chipmunk (Tamias striatus )
Colleen Sharkey is an environmental educator and naturalist whose love for birds has led to a focus on native pollinator conservation. Colleen enjoys sharing her passion for the natural world through workshops, guided hikes and the written word. Find her around central Ohio birding by ear while trail running or studying native plants and insects through a macro lens.