Open Thread - Wednesday December 16, 2015
After last week's weightier Open Thread topic, I thought I would lighten things up a bit with a diary on chipmunks. Being from Florida, we never saw chipmunks in our yard but I always thought they were such cute little critters. I mean, I remember Alvin and the Chipmunks from my youth.
When we came to North Carolina, I was so excited to see real chipmunks in our yard. The variety found in this area is the Eastern chipmunk which is the largest of all the chipmunks. And these little guys were the real life version of those cartoon characters from my childhood. They were so cute scurrying around the yard stuffing their little pouches with nuts (wonderful photo in this link) and other things to eat. Never mind, that they are members of the rodent family along with mice, rats, and squirrels. Something about their cute little bodies with the racing stripes along the sides of their backs made them far more acceptable to me than some rat or even their close cousins, the squirrels.
Once I started feeding birds, the number of chipmunks in my yard seemed to increase. Maybe it was simply that I became more aware of them rather than their numbers actually increasing. Even though I buy a high quality seed mix with no filler, some species of birds that come to my feeders will go through it searching for the seeds or more often, the peanuts that they want. In doing so, they toss good seed out and onto the ground. Then the squirrels and chipmunks come in. The chipmunks are like tiny, little vacuum cleaners, scooping up as much seed as they can and holding it in their fat cheek pouches which can expand to as much as three to four times their normal size. What I never knew was what they did with all that seed until I read an article in the local paper on chipmunks a couple of years ago.
I had always assumed that chipmunks lived in family units under our low wooden deck out back. What I did not know is that chipmunks have extensive underground burrows and are solitary creatures except during mating season which normally occurs twice a year.
The chipmunk's burrow is fascinating in its intricacy. Each animal has his own burrow that is between twenty and thirty feet long with at least one entry and one escape exit and are usually three feet underground. The entry opening is about two inches in diameter and is usually well concealed. Chipmunks go to great lengths to hide the entry and exits from their burrows by carrying the dirt away from these entry areas and scattering it about the ground.
From the entrance, the burrow plunges straight down for a few inches and then descends more gradually until it levels out at a depth of about three feet. During burrow excavation, soil is carried away from the entrance in cheek pouches used to carry food. Because of this, there is little or no evidence of excavated material from the subterranean burrow system.
Often the entry is located near a log or stump to disguise its location and function. Chipmunks are very territorial about their own burrows, but occasionally will raid each others' food stores.
Chipmunks construct two types of burrows within their home ranges: shallow burrows with many entrances and complex networks of interconnected tunnels, and deep burrows that have extremely complicated systems of tunnels and entrances within which food storage areas and a central, leaf-filled nesting chamber are located. The shallow burrows function as temporary refugia for the chipmunk during the day, while the deep burrows are the overnight and overwinter sleeping locales. Burrows are often located on sloping ground, a feature that contributes to efficient water drainage.
Chipmunk burrows are very extensive and have several rooms within them. There are at least three rooms in every burrow and sometimes as many as six. There is a room for sleeping or nesting, at least one and often more rooms for food storage, and a room for waste. Chipmunks are most active during the early morning and early evening hours. However, I have seen them at all times of day. Perhaps that is because my yard has a lot of trees and bushes and thus offers great cover from predators.
Chipmunks technically do not hibernate, but during colder weather go into a state of torpor. They do not live off stored body fat like animals that do hibernate, but instead wake up regularly to dip into their stored food for nourishment.
Because of the damage that their burrows can do to foundations and walls as well as their eating of ornamental bulbs, chipmunks are often considered pests by many people. But I still think they are cute.