Deer Mouse Tracks in the Snow
by Kevin Strauss

One of the reasons that I love new-fallen snow is the way that it changes the way we look at our world. What was once dead, brown grass and bare-branched trees becomes a smooth yard of clean white snow and branches decorated the sparkily clumps of snow. New snow also gives me a wonderful opportunity to see what animals have been walking through my yard.

Recently I found an extensive trail system from some local deer mice (Peromyscus maniculatus). Their tracks criss-crossed my yard and driveway and then disappeared into tunnels in the snowbank. While deer mice are active year-round here in the northwoods, we don’t often see their tiny tracks in lawns or forest floors until the snow falls.

These 4-8 inch long mice (including a 2-4 inch tail), tunnel in snow to reach their food caches of seeds and berries. From the tracks I saw in my yard, it seems as if my mice preferred to tunnel under the snow if they could, possibly to hide from predators like foxes, coyotes and owls.

Deer mice, with their large ears, black eyes and gray to red-brown fur and white bellies can be cute when you see one outdoors. They are considerably less adorable when you find them in your cupboard chewing on your cornflakes. I am as likely as anyone to set a mouse trap to kill a mouse in my house, but I also try to make sure I don’t attract them into my house in the first place. By placing woodpiles or brush piles far from the house, any deer mice that take up residence in your yard will be able to find a comfortable abode without becoming housemates. If you store birdseed in your garage, secure it in a metal garbage can. Mice can and do chew though plastic garbage cans and plastic bags with ease.

In the wild, deer mice take shelter in brush piles and wood piles where they make their nests out of a ball of grass, twigs, feathers, string and whatever other similar building materials they can find.
Deer mice look very similar to the white-footed mouse (Peromyscus leucopus) found in central Minnesota to Texas and from the Great Plains to New England. But deer mice, possibly more adaptable to cold weather, can be found across northern North America and from coast to coast, including the Rocky Mountains and the southwest.

Most deer mice don’t live through their first year. Predators are the primary cause of death. But these mice make up for high mortality with fast reproduction, producing 3-4 litters per year with 2-6 mice per litter. Unlike some mice species, the male helps the female raise the young. A pair of mice can quickly produce a small army of 26 in just one year’s time. What’s more, in less than a year, a mouse could become a great-grandparent as its offspring quickly reproduce. In the boom and bust cycle of mouse life, they feed as much as they can and then reproduce until the food runs out and then they move on to find more food or starve in the journey. Perhaps it is a good thing that so many animals eat mice, otherwise we would be quickly overrun with these fast-moving brown creatures.

The Ely Timberjay