Wildlife Wednesday — deer mice

Deer mice may be one of the most overlooked animals of the Estes Valley. In fact, they are the most widespread and common small mammal in all of North America and can be found from low elevations all the way to the highest peaks. They are especially well adapted to disturbed habitats such as grazed lands, land slides, avalanches, floods or fires, as well as construction sites and homes. Deer mice were the first small mammals to colonize the alluvial fan after the Lawn Lake flood of 1982.

Since Deer mice do not hibernate, you will often see their tracks throughout the winter. Deer mice have 3 strategies to stay warm- huddling with others, nesting, and torpor. Torpor for Deer mice lasts a relatively short period, usually less than a day. They drop their body temperature and just before entering torpor shift their metabolism from burning carbohydrates to fats. In addition, Deer mice have the unique ability to add red blood cells to help survive the cold temperatures. This increase in hemoglobin actually allows them to increase their metabolic rate so they can shiver for long periods to create warmth. Amazing!

Like the Mule deer, Deer mice are known for their large dark eyes and big ears.

Deer mice maintain a gray coat until 30-45 days after birth, becoming brown as a sub adult, and then a rich brown pelage as an adult at 4 months of age. They are weaned around 25 days and can breed at 7 to 8 weeks. It is no wonder they can be so prolific!

Mice are notorious for squeezing through the tiniest passage ways.

Deer mice are nocturnal so are rarely seen during the day.

Although Deer mice have small home ranges and often travel over the same corridors, individuals maintain their own food caches. These are often in distant and inconspicuous places to keep them hidden from others. In the winter, Deer mice live a subnivean life, using the cover of snow for insulation and protection. You will often see their tracks, however, when they emerge from the snow for easier travel. While their diet is mainly seeds, they also consume insects, carrion, bones, fungi, plants, and even leaves and bark when other sources are scarce.