Is that a vole in my chicken coop?

I was putting my chickens away the other night, closing up the coop, and while shutting the door a rodent scurried out. It was about 5 inches long, had a short tail and a blunt nose. What little I saw of it as it streaked by and dove into its' burrow was cute. It looked too big to be a mouse, and, I hoped, too small to be a rat. After consulting some mammal guide books, I was able to determine that it was a meadow vole, Microtus pennsylvanicus (sometimes called the meadow or field mouse). My chances of a correct identification in this case were high since meadow voles are probably the most common rodent in New England.

Voles are mouse-like rodents, but they aren't mice. One difference is that they come from different families; mice are from the taxonomic family Muridae, and voles are from the family Cricetidae. While voles dig tunnels under the ground, mice don't. A famous member of the Cricetidae family is the muskrat.

I first knew a rodent was visiting my chicken coop when a tunnel opening emerged from the subnivean zone, the interface between snow and ground, next to the chicken coop. Voles do this, they tunnel under the snow, making complicated networks of burrows both underground and through the thatch of fields under a protective layer of grass. Because of this, despite being the most common mammal in these parts, they are seldom seen.

Voles, when talked about in the literature, are frequently referred to as pests. This is because they eat the leafy parts of most plants; they'll girdle the apple trees in an orchard and eat the roots of almost anything you would care to grow in a backyard garden. They also have ridges on their teeth that help them chew and grind up the leafy parts and outer skins of most vegetables. Since voles are active year-round, it isn't surprising that one is eating my chicken feed.

Reproduction usually tops the list of fun facts about voles. They are thought to have the fastest reproductive cycles of any mammals on Earth. Female voles can breed when they are as young as one month old; gestation takes only three weeks. Around here, breeding tapers off in the cold winter months, but in warmer climates voles will breed year round. Because of this vole populations can increase very rapidly, often booming then busting as resources become scarce. Lemmings, a type of vole, are notorious for this. Their population cycles often drive those of higher predators, such as the snowy owls that often invade southern lands in search of prey when lemming populations crash .

I don't begrudge the vole (or voles) eating my chicken food. They don't seem to bother the chickens, eat a negligible amount of grain, and, what little I've seen of them, are very cute. What's more, they are vital members of my meadow ecosystem, preyed upon by almost every larger carnivorous mammal.

Sue Pike, a researcher and an environmental sciences and biology teacher at St. Thomas Aquinas High School, welcomes your ideas for future column topics. She may be reached at spike3116@gmail.com or via her blog, sp.stalux.org.