Chipmunks carry their offspring for about a month, and when they are born they are blind and hairless, like mice (they are rodents, after all).They stay in their burrow, underground, for about six to eight weeks, while mom takes care of them. So little has been written about chipmunks that it is difficult to say what role the father plays in their early life. My observations of the adults is that they are fairly solitary and will fight with another chipmunk over food, so I am not sure that they are one big happy family. The mother probably moves the babies by picking them up in her mouth while they are in the burrow, but when they come above ground the babies cling to her back and ride around on her while she looks for food. In five years I have only observed this behavior twice, and I am outside with the chipmunks every day.
The first time I saw the mother chipmunk carrying the babies on her back was very amusing. The new chipmunks were fully covered with fur and looked beautiful. Their fur was perfect, unblemished by any encounters with nasty burrs or clinging seedheads, or bites from bigger chipmunks. They made little soft peeping noises, constantly trying to get mom's attention, gently poking her in the side with their tiny hands while she was trying to get something to eat.
They were clinging to her back and she had obviously had about enough of them. While they were able to walk by themselves, they were used to her feeding them and taking care of them, and they liked it. She put up with it for a few minutes, and then she shook them off and started eating. They tried to climb back on her, but she turned her head and lightly scolded them, with little irritated noises. They paused for a moment and then more vigorously tried to get on her back. Now she had really had it with them. She wheeled around and faced them, practically shrieking. She ranted at them for about twenty seconds, and then she lunged at them, as if she was going to bite them. She seemed to be telling them to get a life and get off her back, permanently.
They started licking their hands and washing their faces, which is what a distressed or upset chipmunk does.
I have seen this behavior over and over. In times of stress, when you don't know what to do, clean your face. The mom continued eating, as if she hadn't had a really good meal in six weeks, and the young ones stayed near her until she was ready to go underground again.
The adult males and females only seem to get together for mating, but the young ones spend a lot of time playing in small groups of twos and threes, and will also happily eat side by side.
The adults all fight over food and will chase and even bite each other if one gets too close to the other while they are trying to eat. I have placed as many as six feeding stations on the deck at one time, about 12 inches apart, and fed the whole group at once. Most of the feeding is orderly, with only a few outbreaks of chasing.
I have read that chipmunks can live as long as six or seven years. I have also read that most wildlife is lucky if it lives over a year (without being eaten or have some other ill fortune occur).
A chipmunk's life goes like this:
If it is born around Valentine's Day (February 14), it will be underground for six to eight weeks, then it will emerge in early April. It is very playful and curious, happy and carefree. Sometimes a little too carefree for its own good. It doesn't recognize that an owl is a predator. I have seen young chipmunks run out on the limb of an oak tree to within eight inches of where a great horned owl was sitting, look at the owl for a few seconds, and then race back down the tree. They will also race up to a dog, but they do recognize that a fox means trouble. I would say that curiosity is their most distinctive characteristic.
All this learning and fun will go on for about a month, and then they become what I call teenagers. No longer babies, but not yet adults. Lots of chasing goes on at this stages. Not much fighting, but lots of running and squealing.
Then they reach adulthood. By this time it is June. Mating begins. If pregnancy occurs (and it seems too, with regularity), they will carry the one to three offspring for about 30 days, which puts the birthdate around the beginning of August. These babies come above ground mid-September, and the mom sees that they get off to a good start. This is the mom that was born on Valentine's Day, remember.
When her offspring reach adulthood, which should be around the beginning of November, she will leave.
The parents leave the nest and the territory where they were born and migrate someplace else. I don't know where they go or how far away, but from experience, it can be as far as three miles (we once discovered one of our old chipmunks all the way in town, about three miles away). Then the cycle begins all over again with the chipmunks that were born in August. Except that in the winter, chipmunks do not migrate to a warmer climate, they go dormant. This is like hibernation, except that they don't completely shut down. They go into their burrows underground and they sleep a lot. They are light sleepers and can awaken if necessary. If they are particularly hungry or it is a warm winter day, they will go out and look for something to eat.
Generally in the wilderness where food is not provided by humans they do not reproduce during the winter. Our chipmunks go semi-dormant but still manage to mate and reproduce year-round. It does not snow in our part of Northern California, and while our property is covered with a dense forest canopy, it is only four miles from the Pacific ocean.
Copyright © 1996 Toni Will-Harris, www.will-harris.com