Vail Daily column: Voles: Unsung heroes of the mountain ecosystem |

Vail Daily column: Voles: Unsung heroes of the mountain ecosystem

Jessica Foulis
Curious Nature
Vail, CO Colorado

Most people can recite at least a few facts about most of the exciting carnivores living in the mountains. Too often, the little guys who make it possible for those large carnivores to exist are forgotten, or worse, they are vilified for doing their ecosystem duty. The job of a vole is not glamorous, but somebody’s got to do it. Voles are often seen as garden pests, but they play an important role in the ecosystem. However, if you prefer they not be a part of your garden ecosystem, there are strategies for nonlethal vole exclusion.

Voles are common rodents throughout North America. Though they are often called meadow mice or field mice, voles can be distinguished from true mice by their short tail, stocky build and small eyes. Most voles are strictly herbivorous, while moles are insectivores. Voles are small pudgy, brown rodents that weigh between 0.8 and 3 ounces and measure between 4 and 8.5 inches in length. They have blunt faces with small eyes, small ears, short legs and usually a short, hairless tail.

Females are ready to breed when they are three weeks old and can have as many as 12 litters per year, with three to 10 babies per litter. Individual life expectancy is three to six months.

As generalists, voles are not picky eaters. They prefer young succulent plants but will change their diet based on what is available. Voles are active day and night, year-round, and can consume almost their entire weight in plant material daily. These voracious little eaters have a very important niche in the local ecosystem, turning plant material into meat and making that energy available for carnivores such as foxes, coyotes, bobcats, owls, hawks, weasels, skunks and badgers. Voles spend the winter in the subnivean zone, carrying on life under the snow.

Often at odds with their human counterparts, voles are nature’s little gardeners. As they gobble up plants, the waste they leave behind returns nutrients to the soil, increasing fertility. The telltale tunnels through which the voles travel serve to aerate the soil, mixing in air and water.

For the very same reasons voles are important to their ecosystem, they have become the bane of existence for many gardeners and turf managers. Although rodenticides do little to decrease vole populations in the long term due to their high fecundity and fumigants are rendered useless by the voles’ clever burrow system, there are successful nonlethal behavioral controls. In fact, the fall is the best time to act by cutting back vegetation and discouraging voles by removing their habitat. Another option is to encourage predators and participate in the food web. Perhaps one day we will all understand our niche in the ecosystem and be able to appreciate the small, unsung heroes that make it all possible.

Jessica Foulis is a natural science educator at Walking Mountains Science Center. She strives to awaken a sense of wonder in the children who participate in her field programs. In her free time, she enjoys playing outside with her dog and skiing and is an avid vole enthusiast.

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